28 changed files with 1189 additions and 1796 deletions
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@ -1,19 +0,0 @@
-# To get started with Dependabot version updates, you'll need to specify which
-# package ecosystems to update and where the package manifests are located.
-# Please see the documentation for all configuration options:
-# https://help.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
-
-version: 2
-updates:
-
-  # Maintain dependencies for GitHub Actions
-  - package-ecosystem: "github-actions"
-    directory: "/"
-    schedule:
-      interval: "daily"
-
-  # Maintain dependencies for Golang
-  - package-ecosystem: "gomod"
-    directory: "/"
-    schedule:
-      interval: "daily"
--- a/.github/stale.sh
+++ b/.github/stale.sh
@ -0,0 +1,13 @@
+#!/bin/bash -ex
+
+export PATH=$PATH:$(pwd)/bin
+export GO111MODULE=on
+export GOBIN=$(pwd)/bin
+
+#go get github.com/rvflash/goup@v0.4.1
+
+#goup -v ./...
+#go get github.com/psampaz/go-mod-outdated@v0.6.0
+go list -u -m -mod=mod -json all | go-mod-outdated -update -direct -ci || true
+
+#go list -u -m -json all | go-mod-outdated -update
--- a/.github/workflows/autoapprove.yml
+++ b/.github/workflows/autoapprove.yml
@ -1,20 +0,0 @@
-name: "autoapprove"
-
-on:
-  pull_request_target:
-    types: [assigned, opened, synchronize, reopened]
-
-permissions:
-  pull-requests: write
-  contents: write
-
-jobs:
-  autoapprove:
-    runs-on: ubuntu-latest
-    steps:
-      - name: approve
-        uses: hmarr/auto-approve-action@v3
-        if: github.actor == 'vtolstov' || github.actor == 'dependabot[bot]'
-        id: approve
-        with:
-          github-token: ${{ secrets.GITHUB_TOKEN }}
--- a/.github/workflows/automerge.yml
+++ b/.github/workflows/automerge.yml
@ -1,21 +0,0 @@
-name: "automerge"
-
-on:
-  pull_request_target:
-    types: [assigned, opened, synchronize, reopened]
-
-permissions:
-  pull-requests: write
-  contents: write
-
-jobs:
-  automerge:
-    runs-on: ubuntu-latest
-    if: github.actor == 'vtolstov'
-    steps:
-      - name: merge
-        id: merge
-        run: gh pr merge --auto --merge "$PR_URL"
-        env:
-          PR_URL: ${{github.event.pull_request.html_url}}
-          GITHUB_TOKEN: ${{secrets.TOKEN}}
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@ -3,20 +3,19 @@ on:
 push:
    branches:
    - master
-    - v3
 jobs:
  test:
    name: test
    runs-on: ubuntu-latest
    steps:
    - name: setup
-      uses: actions/setup-go@v3
+      uses: actions/setup-go@v1
      with:
-        go-version: 1.17
+        go-version: 1.15
    - name: checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v2
    - name: cache
-      uses: actions/cache@v3
+      uses: actions/cache@v2
      with:
        path: ~/go/pkg/mod
        key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
@ -32,9 +31,9 @@ jobs:
    runs-on: ubuntu-latest
    steps:
      - name: checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v2
      - name: lint
-        uses: golangci/golangci-lint-action@v3.4.0
+        uses: golangci/golangci-lint-action@v1
        continue-on-error: true
        with:
          # Required: the version of golangci-lint is required and must be specified without patch version: we always use the latest patch version.
--- a/.github/workflows/codeql-analysis.yml
+++ b/.github/workflows/codeql-analysis.yml
@ -1,78 +0,0 @@
-# For most projects, this workflow file will not need changing; you simply need
-# to commit it to your repository.
-#
-# You may wish to alter this file to override the set of languages analyzed,
-# or to provide custom queries or build logic.
-#
-# ******** NOTE ********
-# We have attempted to detect the languages in your repository. Please check
-# the `language` matrix defined below to confirm you have the correct set of
-# supported CodeQL languages.
-#
-name: "codeql"
-
-on:
-  workflow_run:
-    workflows: ["prbuild"]
-    types:
-      - completed
-  push:
-    branches: [ master, v3 ]
-  pull_request:
-    # The branches below must be a subset of the branches above
-    branches: [ master, v3 ]
-  schedule:
-    - cron: '34 1 * * 0'
-
-jobs:
-  analyze:
-    name: analyze
-    runs-on: ubuntu-latest
-    permissions:
-      actions: read
-      contents: read
-      security-events: write
-
-    strategy:
-      fail-fast: false
-      matrix:
-        language: [ 'go' ]
-        # CodeQL supports [ 'cpp', 'csharp', 'go', 'java', 'javascript', 'python' ]
-        # Learn more:
-        # https://docs.github.com/en/free-pro-team@latest/github/finding-security-vulnerabilities-and-errors-in-your-code/configuring-code-scanning#changing-the-languages-that-are-analyzed
-
-    steps:
-    - name: checkout
-      uses: actions/checkout@v3
-    - name: setup
-      uses: actions/setup-go@v3
-      with:
-        go-version: 1.17
-    # Initializes the CodeQL tools for scanning.
-    - name: init
-      uses: github/codeql-action/init@v2
-      with:
-        languages: ${{ matrix.language }}
-        # If you wish to specify custom queries, you can do so here or in a config file.
-        # By default, queries listed here will override any specified in a config file.
-        # Prefix the list here with "+" to use these queries and those in the config file.
-        # queries: ./path/to/local/query, your-org/your-repo/queries@main
-
-    # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
-    # If this step fails, then you should remove it and run the build manually (see below)
-    - name: autobuild
-      uses: github/codeql-action/autobuild@v2
-
-    # ℹ️ Command-line programs to run using the OS shell.
-    # 📚 https://git.io/JvXDl
-
-    # ✏️ If the Autobuild fails above, remove it and uncomment the following three lines
-    #    and modify them (or add more) to build your code if your project
-    #    uses a compiled language
-
-    #- run: |
-    #   make bootstrap
-    #   make release
-
-    - name: analyze
-      uses: github/codeql-action/analyze@v2
--- a/.github/workflows/dependabot-automerge.yml
+++ b/.github/workflows/dependabot-automerge.yml
@ -1,27 +0,0 @@
-name: "dependabot-automerge"
-
-on:
-  pull_request_target:
-    types: [assigned, opened, synchronize, reopened]
-
-permissions:
-  pull-requests: write
-  contents: write
-
-jobs:
-  automerge:
-    runs-on: ubuntu-latest
-    if: github.actor == 'dependabot[bot]'
-    steps:
-      - name: metadata
-        id: metadata
-        uses: dependabot/fetch-metadata@v1.3.6
-        with:
-          github-token: "${{ secrets.TOKEN }}"
-      - name: merge
-        id: merge
-        if: ${{contains(steps.metadata.outputs.dependency-names, 'go.unistack.org')}}
-        run: gh pr merge --auto --merge "$PR_URL"
-        env:
-          PR_URL: ${{github.event.pull_request.html_url}}
-          GITHUB_TOKEN: ${{secrets.TOKEN}}
--- a/.github/workflows/pr.yml
+++ b/.github/workflows/pr.yml
@ -3,20 +3,19 @@ on:
  pull_request:
    branches:
    - master
-    - v3
 jobs:
  test:
    name: test
    runs-on: ubuntu-latest
    steps:
    - name: setup
-      uses: actions/setup-go@v3
+      uses: actions/setup-go@v1
      with:
-        go-version: 1.17
+        go-version: 1.15
    - name: checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v2
    - name: cache
-      uses: actions/cache@v3
+      uses: actions/cache@v2
      with:
        path: ~/go/pkg/mod
        key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
@ -32,9 +31,9 @@ jobs:
    runs-on: ubuntu-latest
    steps:
      - name: checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v2
      - name: lint
-        uses: golangci/golangci-lint-action@v3.4.0
+        uses: golangci/golangci-lint-action@v1
        continue-on-error: true
        with:
          # Required: the version of golangci-lint is required and must be specified without patch version: we always use the latest patch version.
--- a/.gitignore
+++ b/.gitignore
@ -1,24 +0,0 @@
-# Binaries for programs and plugins
-*.exe
-*.exe~
-*.dll
-*.so
-*.dylib
-bin
-
-# Test binary, built with `go test -c`
-*.test
-
-# Output of the go coverage tool, specifically when used with LiteIDE
-*.out
-
-# Dependency directories (remove the comment below to include it)
-# vendor/
-
-# Go workspace file
-go.work
-
-# General
-.DS_Store
-.idea
-.vscode
--- a/.golangci.yml
+++ b/.golangci.yml
@ -1,44 +0,0 @@
-run:
-  concurrency: 4
-  deadline: 5m
-  issues-exit-code: 1
-  tests: true
-
-linters-settings:
-  govet:
-    check-shadowing: true
-    enable:
-      - fieldalignment
-
-linters:
-  enable:
-    - govet
-    - deadcode
-    - errcheck
-    - govet
-    - ineffassign
-    - staticcheck
-    - structcheck
-    - typecheck
-    - unused
-    - varcheck
-    - bodyclose
-    - gci
-    - goconst
-    - gocritic
-    - gosimple
-    - gofmt
-    - gofumpt
-    - goimports
-    - golint
-    - gosec
-    - makezero
-    - misspell
-    - nakedret
-    - nestif
-    - nilerr
-    - noctx
-    - prealloc
-    - unconvert
-    - unparam
-  disable-all: false
--- a/192
+++ b/192
@ -1,192 +0,0 @@
-
-                                 Apache License
-                           Version 2.0, January 2004
-                        http://www.apache.org/licenses/
-
-   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
-
-   1. Definitions.
-
-      "License" shall mean the terms and conditions for use, reproduction,
-      and distribution as defined by Sections 1 through 9 of this document.
-
-      "Licensor" shall mean the copyright owner or entity authorized by
-      the copyright owner that is granting the License.
-
-      "Legal Entity" shall mean the union of the acting entity and all
-      other entities that control, are controlled by, or are under common
-      control with that entity. For the purposes of this definition,
-      "control" means (i) the power, direct or indirect, to cause the
-      direction or management of such entity, whether by contract or
-      otherwise, or (ii) ownership of fifty percent (50%) or more of the
-      outstanding shares, or (iii) beneficial ownership of such entity.
-
-      "You" (or "Your") shall mean an individual or Legal Entity
-      exercising permissions granted by this License.
-
-      "Source" form shall mean the preferred form for making modifications,
-      including but not limited to software source code, documentation
-      source, and configuration files.
-
-      "Object" form shall mean any form resulting from mechanical
-      transformation or translation of a Source form, including but
-      not limited to compiled object code, generated documentation,
-      and conversions to other media types.
-
-      "Work" shall mean the work of authorship, whether in Source or
-      Object form, made available under the License, as indicated by a
-      copyright notice that is included in or attached to the work
-      (an example is provided in the Appendix below).
-
-      "Derivative Works" shall mean any work, whether in Source or Object
-      form, that is based on (or derived from) the Work and for which the
-      editorial revisions, annotations, elaborations, or other modifications
-      represent, as a whole, an original work of authorship. For the purposes
-      of this License, Derivative Works shall not include works that remain
-      separable from, or merely link (or bind by name) to the interfaces of,
-      the Work and Derivative Works thereof.
-
-      "Contribution" shall mean any work of authorship, including
-      the original version of the Work and any modifications or additions
-      to that Work or Derivative Works thereof, that is intentionally
-      submitted to Licensor for inclusion in the Work by the copyright owner
-      or by an individual or Legal Entity authorized to submit on behalf of
-      the copyright owner. For the purposes of this definition, "submitted"
-      means any form of electronic, verbal, or written communication sent
-      to the Licensor or its representatives, including but not limited to
-      communication on electronic mailing lists, source code control systems,
-      and issue tracking systems that are managed by, or on behalf of, the
-      Licensor for the purpose of discussing and improving the Work, but
-      excluding communication that is conspicuously marked or otherwise
-      designated in writing by the copyright owner as "Not a Contribution."
-
-      "Contributor" shall mean Licensor and any individual or Legal Entity
-      on behalf of whom a Contribution has been received by Licensor and
-      subsequently incorporated within the Work.
-
-   2. Grant of Copyright License. Subject to the terms and conditions of
-      this License, each Contributor hereby grants to You a perpetual,
-      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
-      copyright license to reproduce, prepare Derivative Works of,
-      publicly display, publicly perform, sublicense, and distribute the
-      Work and such Derivative Works in Source or Object form.
-
-   3. Grant of Patent License. Subject to the terms and conditions of
-      this License, each Contributor hereby grants to You a perpetual,
-      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
-      (except as stated in this section) patent license to make, have made,
-      use, offer to sell, sell, import, and otherwise transfer the Work,
-      where such license applies only to those patent claims licensable
-      by such Contributor that are necessarily infringed by their
-      Contribution(s) alone or by combination of their Contribution(s)
-      with the Work to which such Contribution(s) was submitted. If You
-      institute patent litigation against any entity (including a
-      cross-claim or counterclaim in a lawsuit) alleging that the Work
-      or a Contribution incorporated within the Work constitutes direct
-      or contributory patent infringement, then any patent licenses
-      granted to You under this License for that Work shall terminate
-      as of the date such litigation is filed.
-
-   4. Redistribution. You may reproduce and distribute copies of the
-      Work or Derivative Works thereof in any medium, with or without
-      modifications, and in Source or Object form, provided that You
-      meet the following conditions:
-
-      (a) You must give any other recipients of the Work or
-          Derivative Works a copy of this License; and
-
-      (b) You must cause any modified files to carry prominent notices
-          stating that You changed the files; and
-
-      (c) You must retain, in the Source form of any Derivative Works
-          that You distribute, all copyright, patent, trademark, and
-          attribution notices from the Source form of the Work,
-          excluding those notices that do not pertain to any part of
-          the Derivative Works; and
-
-      (d) If the Work includes a "NOTICE" text file as part of its
-          distribution, then any Derivative Works that You distribute must
-          include a readable copy of the attribution notices contained
-          within such NOTICE file, excluding those notices that do not
-          pertain to any part of the Derivative Works, in at least one
-          of the following places: within a NOTICE text file distributed
-          as part of the Derivative Works; within the Source form or
-          documentation, if provided along with the Derivative Works; or,
-          within a display generated by the Derivative Works, if and
-          wherever such third-party notices normally appear. The contents
-          of the NOTICE file are for informational purposes only and
-          do not modify the License. You may add Your own attribution
-          notices within Derivative Works that You distribute, alongside
-          or as an addendum to the NOTICE text from the Work, provided
-          that such additional attribution notices cannot be construed
-          as modifying the License.
-
-      You may add Your own copyright statement to Your modifications and
-      may provide additional or different license terms and conditions
-      for use, reproduction, or distribution of Your modifications, or
-      for any such Derivative Works as a whole, provided Your use,
-      reproduction, and distribution of the Work otherwise complies with
-      the conditions stated in this License.
-
-   5. Submission of Contributions. Unless You explicitly state otherwise,
-      any Contribution intentionally submitted for inclusion in the Work
-      by You to the Licensor shall be under the terms and conditions of
-      this License, without any additional terms or conditions.
-      Notwithstanding the above, nothing herein shall supersede or modify
-      the terms of any separate license agreement you may have executed
-      with Licensor regarding such Contributions.
-
-   6. Trademarks. This License does not grant permission to use the trade
-      names, trademarks, service marks, or product names of the Licensor,
-      except as required for reasonable and customary use in describing the
-      origin of the Work and reproducing the content of the NOTICE file.
-
-   7. Disclaimer of Warranty. Unless required by applicable law or
-      agreed to in writing, Licensor provides the Work (and each
-      Contributor provides its Contributions) on an "AS IS" BASIS,
-      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
-      implied, including, without limitation, any warranties or conditions
-      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
-      PARTICULAR PURPOSE. You are solely responsible for determining the
-      appropriateness of using or redistributing the Work and assume any
-      risks associated with Your exercise of permissions under this License.
-
-   8. Limitation of Liability. In no event and under no legal theory,
-      whether in tort (including negligence), contract, or otherwise,
-      unless required by applicable law (such as deliberate and grossly
-      negligent acts) or agreed to in writing, shall any Contributor be
-      liable to You for damages, including any direct, indirect, special,
-      incidental, or consequential damages of any character arising as a
-      result of this License or out of the use or inability to use the
-      Work (including but not limited to damages for loss of goodwill,
-      work stoppage, computer failure or malfunction, or any and all
-      other commercial damages or losses), even if such Contributor
-      has been advised of the possibility of such damages.
-
-   9. Accepting Warranty or Additional Liability. While redistributing
-      the Work or Derivative Works thereof, You may choose to offer,
-      and charge a fee for, acceptance of support, warranty, indemnity,
-      or other liability obligations and/or rights consistent with this
-      License. However, in accepting such obligations, You may act only
-      on Your own behalf and on Your sole responsibility, not on behalf
-      of any other Contributor, and only if You agree to indemnify,
-      defend, and hold each Contributor harmless for any liability
-      incurred by, or claims asserted against, such Contributor by reason
-      of your accepting any such warranty or additional liability.
-
-   END OF TERMS AND CONDITIONS
-
-   Copyright 2015-2020 Asim Aslam.
-   Copyright 2019-2020 Unistack LLC.
-
-   Licensed under the Apache License, Version 2.0 (the "License");
-   you may not use this file except in compliance with the License.
-   You may obtain a copy of the License at
-
-       http://www.apache.org/licenses/LICENSE-2.0
-
-   Unless required by applicable law or agreed to in writing, software
-   distributed under the License is distributed on an "AS IS" BASIS,
-   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-   See the License for the specific language governing permissions and
-   limitations under the License.
--- a/README.md
+++ b/README.md
@ -0,0 +1,25 @@
+# GRPC Client
+
+The grpc client is a [micro.Client](https://godoc.org/github.com/micro/go-micro/client#Client) compatible client.
+
+## Overview
+
+The client makes use of the [google.golang.org/grpc](google.golang.org/grpc) framework for the underlying communication mechanism.
+
+## Usage
+
+Specify the client to your micro service
+
+```go
+import (
+	"github.com/micro/go-micro"
+	"github.com/micro/go-plugins/client/grpc"
+)
+
+func main() {
+	service := micro.NewService(
+		micro.Name("greeter"),
+		micro.Client(grpc.NewClient()),
+	)
+}
+```
--- a/codec.go
+++ b/codec.go
@ -1,127 +1,231 @@
 package grpc

 import (
-	"io"
+	b "bytes"
+	"encoding/json"
+	"fmt"
+	"strings"

-	"go.unistack.org/micro/v3/codec"
+	oldjsonpb "github.com/golang/protobuf/jsonpb"
+	oldproto "github.com/golang/protobuf/proto"
+	bytes "github.com/unistack-org/micro-codec-bytes"
+	"github.com/unistack-org/micro/v3/codec"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/encoding"
+	jsonpb "google.golang.org/protobuf/encoding/protojson"
+	"google.golang.org/protobuf/proto"
 )

+type jsonCodec struct{}
+type protoCodec struct{}
+type bytesCodec struct{}
+type wrapCodec struct{ encoding.Codec }
+
+var jsonpbMarshaler = &jsonpb.MarshalOptions{}
+var oldjsonpbMarshaler = &oldjsonpb.Marshaler{}
+var useNumber bool
+
 var (
-	_ encoding.Codec = &wrapMicroCodec{}
-	_ codec.Codec    = &wrapGrpcCodec{}
+	defaultGRPCCodecs = map[string]encoding.Codec{
+		"application/json":         jsonCodec{},
+		"application/proto":        protoCodec{},
+		"application/protobuf":     protoCodec{},
+		"application/octet-stream": protoCodec{},
+		"application/grpc":         protoCodec{},
+		"application/grpc+json":    jsonCodec{},
+		"application/grpc+proto":   protoCodec{},
+		"application/grpc+bytes":   bytesCodec{},
+	}
 )

-type wrapStream struct{ grpc.ClientStream }
-
-func (w *wrapStream) Write(d []byte) (int, error) {
-	n := len(d)
-	err := w.ClientStream.SendMsg(&codec.Frame{Data: d})
-	return n, err
+// UseNumber fix unmarshal Number(8234567890123456789) to interface(8.234567890123457e+18)
+func UseNumber() {
+	useNumber = true
 }

-func (w *wrapStream) Read(d []byte) (int, error) {
-	m := &codec.Frame{}
-	err := w.ClientStream.RecvMsg(m)
-	copy(d, m.Data)
-	return len(d), err
-}
-
-type wrapMicroCodec struct{ codec.Codec }
-
-func (w *wrapMicroCodec) Name() string {
-	return w.Codec.String()
-}
-
-func (w *wrapMicroCodec) Marshal(v interface{}) ([]byte, error) {
-	return w.Codec.Marshal(v)
-}
-
-func (w *wrapMicroCodec) Unmarshal(d []byte, v interface{}) error {
-	return w.Codec.Unmarshal(d, v)
-}
-
-type wrapGrpcCodec struct{ encoding.Codec }
-
-func (w *wrapGrpcCodec) String() string {
+func (w wrapCodec) String() string {
 	return w.Codec.Name()
 }

-func (w *wrapGrpcCodec) Marshal(v interface{}, opts ...codec.Option) ([]byte, error) {
-	if m, ok := v.(*codec.Frame); ok {
+func (w wrapCodec) Marshal(v interface{}) ([]byte, error) {
+	switch m := v.(type) {
+	case *bytes.Frame:
 		return m.Data, nil
 	}
 	return w.Codec.Marshal(v)
 }

-func (w *wrapGrpcCodec) Unmarshal(d []byte, v interface{}, opts ...codec.Option) error {
-	if d == nil || v == nil {
+func (w wrapCodec) Unmarshal(data []byte, v interface{}) error {
+	if len(data) == 0 {
 		return nil
 	}
-	if m, ok := v.(*codec.Frame); ok {
-		m.Data = d
+	if v == nil {
 		return nil
 	}
-	return w.Codec.Unmarshal(d, v)
+	switch m := v.(type) {
+	case *bytes.Frame:
+		m.Data = data
+		return nil
+	}
+	return w.Codec.Unmarshal(data, v)
+}
+
+func (protoCodec) Marshal(v interface{}) ([]byte, error) {
+	switch m := v.(type) {
+	case *bytes.Frame:
+		return m.Data, nil
+	case proto.Message:
+		return proto.Marshal(m)
+	case oldproto.Message:
+		return oldproto.Marshal(m)
+	}
+	return nil, fmt.Errorf("failed to marshal: %v is not type of *bytes.Frame or proto.Message", v)
+}
+
+func (protoCodec) Unmarshal(data []byte, v interface{}) error {
+	if len(data) == 0 {
+		return nil
+	}
+	if v == nil {
+		return nil
+	}
+	switch m := v.(type) {
+	case *bytes.Frame:
+		m.Data = data
+		return nil
+	case proto.Message:
+		return proto.Unmarshal(data, m)
+	case oldproto.Message:
+		return oldproto.Unmarshal(data, m)
+	}
+	return fmt.Errorf("failed to unmarshal: %v is not type of *bytes.Frame or proto.Message", v)
+}
+
+func (protoCodec) Name() string {
+	return "proto"
+}
+
+func (bytesCodec) Marshal(v interface{}) ([]byte, error) {
+	switch m := v.(type) {
+	case *[]byte:
+		return *m, nil
+	}
+	return nil, fmt.Errorf("failed to marshal: %v is not type of *[]byte", v)
+}
+
+func (bytesCodec) Unmarshal(data []byte, v interface{}) error {
+	if len(data) == 0 {
+		return nil
+	}
+	if v == nil {
+		return nil
+	}
+	switch m := v.(type) {
+	case *[]byte:
+		*m = data
+		return nil
+	}
+	return fmt.Errorf("failed to unmarshal: %v is not type of *[]byte", v)
+}
+
+func (bytesCodec) Name() string {
+	return "bytes"
+}
+
+func (jsonCodec) Marshal(v interface{}) ([]byte, error) {
+	switch m := v.(type) {
+	case *bytes.Frame:
+		return m.Data, nil
+	case proto.Message:
+		return jsonpbMarshaler.Marshal(m)
+	case oldproto.Message:
+		buf, err := oldjsonpbMarshaler.MarshalToString(m)
+		return []byte(buf), err
+	}
+
+	return json.Marshal(v)
+}
+
+func (jsonCodec) Unmarshal(data []byte, v interface{}) error {
+	if len(data) == 0 {
+		return nil
+	}
+	if v == nil {
+		return nil
+	}
+	switch m := v.(type) {
+	case *bytes.Frame:
+		m.Data = data
+		return nil
+	case proto.Message:
+		return jsonpb.Unmarshal(data, m)
+	case oldproto.Message:
+		return oldjsonpb.Unmarshal(b.NewReader(data), m)
+	}
+	dec := json.NewDecoder(b.NewReader(data))
+	if useNumber {
+		dec.UseNumber()
+	}
+	return dec.Decode(v)
+}
+
+func (jsonCodec) Name() string {
+	return "json"
 }

-/*
 type grpcCodec struct {
-	grpc.ServerStream
 	// headers
 	id       string
 	target   string
 	method   string
 	endpoint string

+	s grpc.ClientStream
 	c encoding.Codec
 }

-*/
-
-func (w *wrapGrpcCodec) ReadHeader(conn io.Reader, m *codec.Message, mt codec.MessageType) error {
-	/*
-		if m == nil {
-			m = codec.NewMessage(codec.Request)
-		}
-
-		if md, ok := metadata.FromIncomingContext(g.ServerStream.Context()); ok {
-			if m.Header == nil {
-				m.Header = meta.New(len(md))
-			}
-			for k, v := range md {
-				m.Header[k] = strings.Join(v, ",")
-			}
-		}
-
-		m.Id = g.id
-		m.Target = g.target
-		m.Method = g.method
-		m.Endpoint = g.endpoint
-	*/
+func (g *grpcCodec) ReadHeader(m *codec.Message, mt codec.MessageType) error {
+	md, err := g.s.Header()
+	if err != nil {
+		return err
+	}
+	if m == nil {
+		m = new(codec.Message)
+	}
+	if m.Header == nil {
+		m.Header = make(map[string]string, len(md))
+	}
+	for k, v := range md {
+		m.Header[k] = strings.Join(v, ",")
+	}
+	m.Id = g.id
+	m.Target = g.target
+	m.Method = g.method
+	m.Endpoint = g.endpoint
 	return nil
 }

-func (w *wrapGrpcCodec) ReadBody(conn io.Reader, v interface{}) error {
-	// caller has requested a frame
-	if m, ok := v.(*codec.Frame); ok {
-		_, err := conn.Read(m.Data)
-		return err
+func (g *grpcCodec) ReadBody(v interface{}) error {
+	switch m := v.(type) {
+	case *bytes.Frame:
+		return g.s.RecvMsg(m)
 	}
-	return codec.ErrInvalidMessage
+	return g.s.RecvMsg(v)
 }

-func (w *wrapGrpcCodec) Write(conn io.Writer, m *codec.Message, v interface{}) error {
+func (g *grpcCodec) Write(m *codec.Message, v interface{}) error {
 	// if we don't have a body
 	if v != nil {
-		b, err := w.Marshal(v)
-		if err != nil {
-			return err
-		}
-		m.Body = b
+		return g.s.SendMsg(v)
 	}
 	// write the body using the framing codec
-	_, err := conn.Write(m.Body)
-	return err
+	return g.s.SendMsg(&bytes.Frame{Data: m.Body})
+}
+
+func (g *grpcCodec) Close() error {
+	return g.s.CloseSend()
+}
+
+func (g *grpcCodec) String() string {
+	return g.c.Name()
 }
--- a/error.go
+++ b/error.go
@ -1,7 +1,8 @@
 package grpc

 import (
-	"go.unistack.org/micro/v3/errors"
+	pberr "github.com/unistack-org/micro-client-grpc/errors"
+	"github.com/unistack-org/micro/v3/errors"
 	"google.golang.org/grpc/status"
 )

@ -9,46 +10,35 @@ func microError(err error) error {
 	// no error

 	if err == nil {
-		// nothing to do
 		return nil
 	}

 	if verr, ok := err.(*errors.Error); ok {
-		// micro error
 		return verr
 	}

+	if verr, ok := err.(*pberr.Error); ok {
+		return &errors.Error{Id: verr.Id, Code: verr.Code, Detail: verr.Detail, Status: verr.Status}
+	}
+
 	// grpc error
 	s, ok := status.FromError(err)
 	if !ok {
-		// can't get status detals from grpc error, return base error
 		return err
 	}

-	details := s.Details()
-	switch len(details) {
-	case 0:
-		if verr := errors.Parse(s.Message()); verr.Code > 0 {
-			// return micro error
-			return verr
+	// return first error from details
+	if details := s.Details(); len(details) > 0 {
+		if verr, ok := details[0].(error); ok {
+			return microError(verr)
 		}
-		// return base error as it not micro error
-		return err
-	case 1:
-		if verr, ok := details[0].(*errors.Error); ok {
-			// return nested micro error
-			return verr
-		}
-		// return base error as it not holds micro error
-		return err
 	}

-	// attached messages in details more then 1, try to fallback to micro error
-	if verr := errors.Parse(s.Message()); verr.Code > 0 {
-		// return micro error
-		return verr
+	// try to decode micro *errors.Error
+	if e := errors.Parse(s.Message()); e.Code > 0 {
+		return e // actually a micro error
 	}

-	// not micro error return base error
-	return err
+	// fallback
+	return errors.InternalServerError("go.micro.client", s.Message())
 }
--- a/errors/errors.go
+++ b/errors/errors.go
@ -0,0 +1,159 @@
+package errors
+
+import (
+	"fmt"
+)
+
+func (e *Error) Error() string {
+	return fmt.Sprintf(`{"id":"%s","code":%d,"detail":"%s","status":"%s"}`, e.Id, e.Code, e.Detail, e.Status)
+}
+
+// New generates a custom error.
+func New(id, detail string, code int32) error {
+	return &Error{
+		Id:     id,
+		Code:   code,
+		Detail: detail,
+		//	Status: http.StatusText(int(code)),
+	}
+}
+
+// BadRequest generates a 400 error.
+func BadRequest(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   400,
+		Detail: fmt.Sprintf(format, a...),
+		//		Status: http.StatusText(400),
+	}
+}
+
+// Unauthorized generates a 401 error.
+func Unauthorized(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   401,
+		Detail: fmt.Sprintf(format, a...),
+		//		Status: http.StatusText(401),
+	}
+}
+
+// Forbidden generates a 403 error.
+func Forbidden(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   403,
+		Detail: fmt.Sprintf(format, a...),
+		//		Status: http.StatusText(403),
+	}
+}
+
+// NotFound generates a 404 error.
+func NotFound(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   404,
+		Detail: fmt.Sprintf(format, a...),
+		//	Status: http.StatusText(404),
+	}
+}
+
+// MethodNotAllowed generates a 405 error.
+func MethodNotAllowed(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   405,
+		Detail: fmt.Sprintf(format, a...),
+		//Status: http.StatusText(405),
+	}
+}
+
+// Timeout generates a 408 error.
+func Timeout(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   408,
+		Detail: fmt.Sprintf(format, a...),
+		//Status: http.StatusText(408),
+	}
+}
+
+// Conflict generates a 409 error.
+func Conflict(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   409,
+		Detail: fmt.Sprintf(format, a...),
+		//Status: http.StatusText(409),
+	}
+}
+
+// InternalServerError generates a 500 error.
+func InternalServerError(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   500,
+		Detail: fmt.Sprintf(format, a...),
+		//Status: http.StatusText(500),
+	}
+}
+
+// NotImplemented generates a 501 error
+func NotImplemented(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   501,
+		Detail: fmt.Sprintf(format, a...),
+		//Status: http.StatusText(501),
+	}
+}
+
+// BadGateway generates a 502 error
+func BadGateway(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   502,
+		Detail: fmt.Sprintf(format, a...),
+		//	Status: http.StatusText(502),
+	}
+}
+
+// ServiceUnavailable generates a 503 error
+func ServiceUnavailable(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   503,
+		Detail: fmt.Sprintf(format, a...),
+		//Status: http.StatusText(503),
+	}
+}
+
+// GatewayTimeout generates a 504 error
+func GatewayTimeout(id, format string, a ...interface{}) error {
+	return &Error{
+		Id:     id,
+		Code:   504,
+		Detail: fmt.Sprintf(format, a...),
+		//Status: http.StatusText(504),
+	}
+}
+
+// Equal tries to compare errors
+func Equal(err1 error, err2 error) bool {
+	verr1, ok1 := err1.(*Error)
+	verr2, ok2 := err2.(*Error)
+
+	if ok1 != ok2 {
+		return false
+	}
+
+	if !ok1 {
+		return err1 == err2
+	}
+
+	if verr1.Code != verr2.Code {
+		return false
+	}
+
+	return true
+}
--- a/errors/errors.pb.go
+++ b/errors/errors.pb.go
@ -0,0 +1,176 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.25.0-devel
+// 	protoc        v3.6.1
+// source: errors.proto
+
+package errors
+
+import (
+	proto "github.com/golang/protobuf/proto"
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sync "sync"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+// This is a compile-time assertion that a sufficiently up-to-date version
+// of the legacy proto package is being used.
+const _ = proto.ProtoPackageIsVersion4
+
+type Error struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	Id     string `protobuf:"bytes,1,opt,name=id,proto3" json:"id,omitempty"`
+	Code   int32  `protobuf:"varint,2,opt,name=code,proto3" json:"code,omitempty"`
+	Detail string `protobuf:"bytes,3,opt,name=detail,proto3" json:"detail,omitempty"`
+	Status string `protobuf:"bytes,4,opt,name=status,proto3" json:"status,omitempty"`
+}
+
+func (x *Error) Reset() {
+	*x = Error{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_errors_proto_msgTypes[0]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *Error) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*Error) ProtoMessage() {}
+
+func (x *Error) ProtoReflect() protoreflect.Message {
+	mi := &file_errors_proto_msgTypes[0]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use Error.ProtoReflect.Descriptor instead.
+func (*Error) Descriptor() ([]byte, []int) {
+	return file_errors_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *Error) GetId() string {
+	if x != nil {
+		return x.Id
+	}
+	return ""
+}
+
+func (x *Error) GetCode() int32 {
+	if x != nil {
+		return x.Code
+	}
+	return 0
+}
+
+func (x *Error) GetDetail() string {
+	if x != nil {
+		return x.Detail
+	}
+	return ""
+}
+
+func (x *Error) GetStatus() string {
+	if x != nil {
+		return x.Status
+	}
+	return ""
+}
+
+var File_errors_proto protoreflect.FileDescriptor
+
+var file_errors_proto_rawDesc = []byte{
+	0x0a, 0x0c, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x12, 0x25,
+	0x6f, 0x72, 0x67, 0x2e, 0x75, 0x6e, 0x69, 0x73, 0x74, 0x61, 0x63, 0x6b, 0x2e, 0x6d, 0x69, 0x63,
+	0x72, 0x6f, 0x2e, 0x63, 0x6c, 0x69, 0x65, 0x6e, 0x74, 0x2e, 0x67, 0x72, 0x70, 0x63, 0x2e, 0x65,
+	0x72, 0x72, 0x6f, 0x72, 0x73, 0x22, 0x5b, 0x0a, 0x05, 0x45, 0x72, 0x72, 0x6f, 0x72, 0x12, 0x0e,
+	0x0a, 0x02, 0x69, 0x64, 0x18, 0x01, 0x20, 0x01, 0x28, 0x09, 0x52, 0x02, 0x69, 0x64, 0x12, 0x12,
+	0x0a, 0x04, 0x63, 0x6f, 0x64, 0x65, 0x18, 0x02, 0x20, 0x01, 0x28, 0x05, 0x52, 0x04, 0x63, 0x6f,
+	0x64, 0x65, 0x12, 0x16, 0x0a, 0x06, 0x64, 0x65, 0x74, 0x61, 0x69, 0x6c, 0x18, 0x03, 0x20, 0x01,
+	0x28, 0x09, 0x52, 0x06, 0x64, 0x65, 0x74, 0x61, 0x69, 0x6c, 0x12, 0x16, 0x0a, 0x06, 0x73, 0x74,
+	0x61, 0x74, 0x75, 0x73, 0x18, 0x04, 0x20, 0x01, 0x28, 0x09, 0x52, 0x06, 0x73, 0x74, 0x61, 0x74,
+	0x75, 0x73, 0x42, 0x0a, 0x5a, 0x08, 0x2e, 0x3b, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x62, 0x06,
+	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
+}
+
+var (
+	file_errors_proto_rawDescOnce sync.Once
+	file_errors_proto_rawDescData = file_errors_proto_rawDesc
+)
+
+func file_errors_proto_rawDescGZIP() []byte {
+	file_errors_proto_rawDescOnce.Do(func() {
+		file_errors_proto_rawDescData = protoimpl.X.CompressGZIP(file_errors_proto_rawDescData)
+	})
+	return file_errors_proto_rawDescData
+}
+
+var file_errors_proto_msgTypes = make([]protoimpl.MessageInfo, 1)
+var file_errors_proto_goTypes = []interface{}{
+	(*Error)(nil), // 0: org.unistack.micro.client.grpc.errors.Error
+}
+var file_errors_proto_depIdxs = []int32{
+	0, // [0:0] is the sub-list for method output_type
+	0, // [0:0] is the sub-list for method input_type
+	0, // [0:0] is the sub-list for extension type_name
+	0, // [0:0] is the sub-list for extension extendee
+	0, // [0:0] is the sub-list for field type_name
+}
+
+func init() { file_errors_proto_init() }
+func file_errors_proto_init() {
+	if File_errors_proto != nil {
+		return
+	}
+	if !protoimpl.UnsafeEnabled {
+		file_errors_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*Error); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: file_errors_proto_rawDesc,
+			NumEnums:      0,
+			NumMessages:   1,
+			NumExtensions: 0,
+			NumServices:   0,
+		},
+		GoTypes:           file_errors_proto_goTypes,
+		DependencyIndexes: file_errors_proto_depIdxs,
+		MessageInfos:      file_errors_proto_msgTypes,
+	}.Build()
+	File_errors_proto = out.File
+	file_errors_proto_rawDesc = nil
+	file_errors_proto_goTypes = nil
+	file_errors_proto_depIdxs = nil
+}
--- a/errors/errors.pb.micro.go
+++ b/errors/errors.pb.micro.go
@ -0,0 +1,21 @@
+// Code generated by protoc-gen-micro. DO NOT EDIT.
+// source: errors.proto
+
+package errors
+
+import (
+	fmt "fmt"
+	proto "github.com/golang/protobuf/proto"
+	math "math"
+)
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion3 // please upgrade the proto package
--- a/errors/errors.proto
+++ b/errors/errors.proto
@ -0,0 +1,11 @@
+syntax = "proto3";
+
+option go_package = ".;errors";
+package org.unistack.micro.client.grpc.errors;
+
+message Error {
+  string id = 1;
+  int32 code = 2;
+  string detail = 3;
+  string status = 4;
+};
--- a/generate.go
+++ b/generate.go
@ -0,0 +1,3 @@
+package grpc
+
+//go:generate protoc -I./errors -I. --go-grpc_out=paths=source_relative:./errors --go_out=paths=source_relative:./errors --micro_out=paths=source_relative:./errors errors/errors.proto
--- a/go.mod
+++ b/go.mod
@ -1,8 +1,15 @@
-module go.unistack.org/micro-client-grpc/v3
+module github.com/unistack-org/micro-client-grpc

-go 1.16
+go 1.15

 require (
-	go.unistack.org/micro/v3 v3.10.22
-	google.golang.org/grpc v1.52.3
+	github.com/golang/protobuf v1.4.2
+	github.com/google/go-cmp v0.5.1 // indirect
+	github.com/unistack-org/micro-codec-bytes v0.0.0-20200828083432-4e49e953d844
+	github.com/unistack-org/micro/v3 v3.0.0-gamma.0.20200920124807-9b11ea527aeb
+	golang.org/x/sys v0.0.0-20200803210538-64077c9b5642 // indirect
+	golang.org/x/text v0.3.3 // indirect
+	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
+	google.golang.org/grpc v1.31.1
+	google.golang.org/protobuf v1.25.0
 )
--- a/go.sum
+++ b/go.sum
--- a/grpc.go
+++ b/grpc.go
@ -1,52 +1,57 @@
 // Package grpc provides a gRPC client
-package grpc // import "go.unistack.org/micro-client-grpc/v3"
+package grpc

 import (
 	"context"
 	"crypto/tls"
 	"fmt"
 	"net"
-	"os"
 	"reflect"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"

-	"go.unistack.org/micro/v3/broker"
-	"go.unistack.org/micro/v3/client"
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/errors"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/selector"
+	raw "github.com/unistack-org/micro-codec-bytes"
+	"github.com/unistack-org/micro/v3/broker"
+	"github.com/unistack-org/micro/v3/client"
+	"github.com/unistack-org/micro/v3/errors"
+	"github.com/unistack-org/micro/v3/metadata"
+
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials"
-	"google.golang.org/grpc/credentials/insecure"
 	"google.golang.org/grpc/encoding"
 	gmetadata "google.golang.org/grpc/metadata"
 )

-const (
-	DefaultContentType = "application/grpc"
-)
-
 type grpcClient struct {
-	pool *ConnPool
-	opts client.Options
+	opts   client.Options
+	codecs map[string]encoding.Codec
+	pool   *pool
+	once   atomic.Value
 	sync.RWMutex
-	init bool
+}
+
+func init() {
+	encoding.RegisterCodec(wrapCodec{jsonCodec{}})
+	encoding.RegisterCodec(wrapCodec{protoCodec{}})
+	encoding.RegisterCodec(wrapCodec{bytesCodec{}})
 }

 // secure returns the dial option for whether its a secure or insecure connection
 func (g *grpcClient) secure(addr string) grpc.DialOption {
 	// first we check if theres'a  tls config
-	if g.opts.TLSConfig != nil {
-		creds := credentials.NewTLS(g.opts.TLSConfig)
-		// return tls config if it exists
-		return grpc.WithTransportCredentials(creds)
+	if g.opts.Context != nil {
+		if v := g.opts.Context.Value(tlsAuth{}); v != nil {
+			tls := v.(*tls.Config)
+			creds := credentials.NewTLS(tls)
+			// return tls config if it exists
+			return grpc.WithTransportCredentials(creds)
+		}
 	}

 	// default config
-	tlsConfig := &tls.Config{MinVersion: tls.VersionTLS12}
+	tlsConfig := &tls.Config{}
 	defaultCreds := grpc.WithTransportCredentials(credentials.NewTLS(tlsConfig))

 	// check if the address is prepended with https
@ -64,41 +69,37 @@ func (g *grpcClient) secure(addr string) grpc.DialOption {
 	}

 	// other fallback to insecure
-	return grpc.WithTransportCredentials(insecure.NewCredentials())
+	return grpc.WithInsecure()
 }

 func (g *grpcClient) call(ctx context.Context, addr string, req client.Request, rsp interface{}, opts client.CallOptions) error {
 	var header map[string]string

-	if md, ok := metadata.FromOutgoingContext(ctx); ok {
+	header = make(map[string]string)
+	if md, ok := metadata.FromContext(ctx); ok {
 		header = make(map[string]string, len(md))
 		for k, v := range md {
 			header[strings.ToLower(k)] = v
 		}
 	} else {
-		header = make(map[string]string, 2)
-	}
-	if opts.RequestMetadata != nil {
-		for k, v := range opts.RequestMetadata {
-			header[k] = v
-		}
+		header = make(map[string]string)
 	}
+
 	// set timeout in nanoseconds
-	header["Grpc-Timeout"] = fmt.Sprintf("%dn", opts.RequestTimeout)
-	header["timeout"] = fmt.Sprintf("%dn", opts.RequestTimeout)
-	header["content-type"] = req.ContentType()
+	header["timeout"] = fmt.Sprintf("%d", opts.RequestTimeout)
+	// set the content type for the request
+	header["x-content-type"] = req.ContentType()

 	md := gmetadata.New(header)
 	ctx = gmetadata.NewOutgoingContext(ctx, md)

-	cf, err := g.newCodec(req.ContentType())
+	cf, err := g.newGRPCCodec(req.ContentType())
 	if err != nil {
 		return errors.InternalServerError("go.micro.client", err.Error())
 	}

 	maxRecvMsgSize := g.maxRecvMsgSizeValue()
 	maxSendMsgSize := g.maxSendMsgSizeValue()
-	cfgService := g.serviceConfig()

 	var grr error

@ -117,47 +118,30 @@ func (g *grpcClient) call(ctx context.Context, addr string, req client.Request,
 			grpc.MaxCallRecvMsgSize(maxRecvMsgSize),
 			grpc.MaxCallSendMsgSize(maxSendMsgSize),
 		),
-		grpc.WithDefaultServiceConfig(cfgService),
 	}

-	if opts := g.getGrpcDialOptions(opts.Context); opts != nil {
+	if opts := g.getGrpcDialOptions(); opts != nil {
 		grpcDialOptions = append(grpcDialOptions, opts...)
 	}

-	contextDialer := g.opts.ContextDialer
-	if opts.ContextDialer != nil {
-		contextDialer = opts.ContextDialer
-	}
-	if contextDialer != nil {
-		grpcDialOptions = append(grpcDialOptions, grpc.WithContextDialer(contextDialer))
-	}
-
-	cc, err := g.pool.Get(dialCtx, addr, grpcDialOptions...)
+	cc, err := g.pool.getConn(dialCtx, addr, grpcDialOptions...)
 	if err != nil {
 		return errors.InternalServerError("go.micro.client", fmt.Sprintf("Error sending request: %v", err))
 	}
 	defer func() {
 		// defer execution of release
-		g.pool.Put(cc, grr)
+		g.pool.release(addr, cc, grr)
 	}()

 	ch := make(chan error, 1)
-	var gmd gmetadata.MD
-
-	grpcCallOptions := []grpc.CallOption{
-		grpc.CallContentSubtype((&wrapMicroCodec{cf}).Name()),
-	}
-
-	if opts := g.getGrpcCallOptions(opts.Context); opts != nil {
-		grpcCallOptions = append(grpcCallOptions, opts...)
-	}
-
-	if opts.ResponseMetadata != nil {
-		gmd = gmetadata.MD{}
-		grpcCallOptions = append(grpcCallOptions, grpc.Header(&gmd))
-	}

 	go func() {
+		grpcCallOptions := []grpc.CallOption{
+			grpc.ForceCodec(cf),
+			grpc.CallContentSubtype(cf.Name())}
+		if opts := g.getGrpcCallOptions(); opts != nil {
+			grpcCallOptions = append(grpcCallOptions, opts...)
+		}
 		err := cc.Invoke(ctx, methodToGRPC(req.Service(), req.Endpoint()), req.Body(), rsp, grpcCallOptions...)
 		ch <- microError(err)
 	}()
@ -169,20 +153,13 @@ func (g *grpcClient) call(ctx context.Context, addr string, req client.Request,
 		grr = errors.Timeout("go.micro.client", "%v", ctx.Err())
 	}

-	if opts.ResponseMetadata != nil {
-		*opts.ResponseMetadata = metadata.New(gmd.Len())
-		for k, v := range gmd {
-			opts.ResponseMetadata.Set(k, strings.Join(v, ","))
-		}
-	}
-
 	return grr
 }

 func (g *grpcClient) stream(ctx context.Context, addr string, req client.Request, rsp interface{}, opts client.CallOptions) error {
 	var header map[string]string

-	if md, ok := metadata.FromOutgoingContext(ctx); ok {
+	if md, ok := metadata.FromContext(ctx); ok {
 		header = make(map[string]string, len(md))
 		for k, v := range md {
 			header[k] = v
@ -193,16 +170,15 @@ func (g *grpcClient) stream(ctx context.Context, addr string, req client.Request

 	// set timeout in nanoseconds
 	if opts.StreamTimeout > time.Duration(0) {
-		header["Grpc-Timeout"] = fmt.Sprintf("%dn", opts.StreamTimeout)
-		header["timeout"] = fmt.Sprintf("%dn", opts.StreamTimeout)
+		header["timeout"] = fmt.Sprintf("%d", opts.StreamTimeout)
 	}
 	// set the content type for the request
-	header["content-type"] = req.ContentType()
+	header["x-content-type"] = req.ContentType()

 	md := gmetadata.New(header)
 	ctx = gmetadata.NewOutgoingContext(ctx, md)

-	cf, err := g.newCodec(req.ContentType())
+	cf, err := g.newGRPCCodec(req.ContentType())
 	if err != nil {
 		return errors.InternalServerError("go.micro.client", err.Error())
 	}
@ -216,34 +192,17 @@ func (g *grpcClient) stream(ctx context.Context, addr string, req client.Request
 	}
 	defer cancel()

-	wc := &wrapMicroCodec{cf}
-
-	maxRecvMsgSize := g.maxRecvMsgSizeValue()
-	maxSendMsgSize := g.maxSendMsgSizeValue()
-	cfgService := g.serviceConfig()
+	wc := wrapCodec{cf}

 	grpcDialOptions := []grpc.DialOption{
 		g.secure(addr),
-		grpc.WithDefaultCallOptions(
-			grpc.MaxCallRecvMsgSize(maxRecvMsgSize),
-			grpc.MaxCallSendMsgSize(maxSendMsgSize),
-		),
-		grpc.WithDefaultServiceConfig(cfgService),
 	}

-	if opts := g.getGrpcDialOptions(opts.Context); opts != nil {
+	if opts := g.getGrpcDialOptions(); opts != nil {
 		grpcDialOptions = append(grpcDialOptions, opts...)
 	}

-	contextDialer := g.opts.ContextDialer
-	if opts.ContextDialer != nil {
-		contextDialer = opts.ContextDialer
-	}
-	if contextDialer != nil {
-		grpcDialOptions = append(grpcDialOptions, grpc.WithContextDialer(contextDialer))
-	}
-
-	cc, err := g.pool.Get(dialCtx, addr, grpcDialOptions...)
+	cc, err := g.pool.getConn(dialCtx, addr, grpcDialOptions...)
 	if err != nil {
 		return errors.InternalServerError("go.micro.client", fmt.Sprintf("Error sending request: %v", err))
 	}
@ -255,17 +214,12 @@ func (g *grpcClient) stream(ctx context.Context, addr string, req client.Request
 	}

 	grpcCallOptions := []grpc.CallOption{
-		// grpc.ForceCodec(wc),
-		grpc.CallContentSubtype(wc.Name()),
+		grpc.ForceCodec(wc),
+		grpc.CallContentSubtype(cf.Name()),
 	}
-	if opts := g.getGrpcCallOptions(opts.Context); opts != nil {
+	if opts := g.getGrpcCallOptions(); opts != nil {
 		grpcCallOptions = append(grpcCallOptions, opts...)
 	}
-	var gmd gmetadata.MD
-	if opts.ResponseMetadata != nil {
-		gmd = gmetadata.MD{}
-		grpcCallOptions = append(grpcCallOptions, grpc.Header(&gmd))
-	}

 	// create a new cancelling context
 	newCtx, cancel := context.WithCancel(ctx)
@ -276,14 +230,19 @@ func (g *grpcClient) stream(ctx context.Context, addr string, req client.Request
 		// cancel the context
 		cancel()
 		// release the connection
-		g.pool.Put(cc, err)
+		g.pool.release(addr, cc, err)
 		// now return the error
 		return errors.InternalServerError("go.micro.client", fmt.Sprintf("Error creating stream: %v", err))
 	}

+	codec := &grpcCodec{
+		s: st,
+		c: wc,
+	}
+
 	// set request codec
 	if r, ok := req.(*grpcRequest); ok {
-		r.codec = cf
+		r.codec = codec
 	}

 	// setup the stream response
@ -295,23 +254,23 @@ func (g *grpcClient) stream(ctx context.Context, addr string, req client.Request
 			conn:   cc,
 			stream: st,
 			codec:  cf,
+			gcodec: codec,
 		},
 		conn: cc,
 		close: func(err error) {
-			// cancel the context if an error occurred
+			// cancel the context if an error occured
 			if err != nil {
 				cancel()
 			}

 			// defer execution of release
-			g.pool.Put(cc, err)
+			g.pool.release(addr, cc, err)
 		},
 	}

 	// set the stream as the response
 	val := reflect.ValueOf(rsp).Elem()
 	val.Set(reflect.ValueOf(stream).Elem())
-
 	return nil
 }

@ -359,35 +318,17 @@ func (g *grpcClient) maxSendMsgSizeValue() int {
 	return v.(int)
 }

-func (g *grpcClient) newCodec(ct string) (codec.Codec, error) {
+func (g *grpcClient) newGRPCCodec(contentType string) (encoding.Codec, error) {
 	g.RLock()
 	defer g.RUnlock()

-	if idx := strings.IndexRune(ct, ';'); idx >= 0 {
-		ct = ct[:idx]
+	if c, ok := g.codecs[contentType]; ok {
+		return wrapCodec{c}, nil
 	}
-
-	if c, ok := g.opts.Codecs[ct]; ok {
-		return c, nil
-	}
-	return nil, codec.ErrUnknownContentType
-}
-
-func (g *grpcClient) serviceConfig() string {
-	if g.opts.Context == nil {
-		return DefaultServiceConfig
-	}
-	v := g.opts.Context.Value(serviceConfigKey{})
-	if v == nil {
-		return DefaultServiceConfig
-	}
-	return v.(string)
+	return nil, fmt.Errorf("Unsupported Content-Type: %s", contentType)
 }

 func (g *grpcClient) Init(opts ...client.Option) error {
-	if len(opts) == 0 && g.init {
-		return nil
-	}
 	size := g.opts.PoolSize
 	ttl := g.opts.PoolTTL

@ -403,27 +344,6 @@ func (g *grpcClient) Init(opts ...client.Option) error {
 		g.pool.Unlock()
 	}

-	if err := g.opts.Broker.Init(); err != nil {
-		return err
-	}
-	if err := g.opts.Tracer.Init(); err != nil {
-		return err
-	}
-	if err := g.opts.Router.Init(); err != nil {
-		return err
-	}
-	if err := g.opts.Logger.Init(); err != nil {
-		return err
-	}
-	if err := g.opts.Meter.Init(); err != nil {
-		return err
-	}
-	if err := g.opts.Transport.Init(); err != nil {
-		return err
-	}
-
-	g.init = true
-
 	return nil
 }

@ -447,7 +367,6 @@ func (g *grpcClient) Call(ctx context.Context, req client.Request, rsp interface
 	}
 	// make a copy of call opts
 	callOpts := g.opts.CallOptions
-
 	for _, opt := range opts {
 		opt(&callOpts)
 	}
@ -496,8 +415,20 @@ func (g *grpcClient) Call(ctx context.Context, req client.Request, rsp interface
 		callOpts.Address = []string{g.opts.Proxy}
 	}

-	var next selector.Next
+	// lookup the route to send the reques to
+	// TODO apply any filtering here
+	routes, err := g.opts.Lookup(ctx, req, callOpts)
+	if err != nil {
+		return errors.InternalServerError("go.micro.client", err.Error())
+	}

+	// balance the list of nodes
+	next, err := callOpts.Selector.Select(routes)
+	if err != nil {
+		return err
+	}
+
+	// return errors.New("go.micro.client", "request timeout", 408)
 	call := func(i int) error {
 		// call backoff first. Someone may want an initial start delay
 		t, err := callOpts.Backoff(ctx, req, i)
@ -510,23 +441,6 @@ func (g *grpcClient) Call(ctx context.Context, req client.Request, rsp interface
 			time.Sleep(t)
 		}

-		if next == nil {
-			var routes []string
-
-			// lookup the route to send the reques to
-			// TODO apply any filtering here
-			routes, err = g.opts.Lookup(ctx, req, callOpts)
-			if err != nil {
-				return errors.InternalServerError("go.micro.client", err.Error())
-			}
-
-			// balance the list of nodes
-			next, err = callOpts.Selector.Select(routes)
-			if err != nil {
-				return err
-			}
-		}
-
 		// get the next node
 		node := next()

@ -618,7 +532,18 @@ func (g *grpcClient) Stream(ctx context.Context, req client.Request, opts ...cli
 		callOpts.Address = []string{g.opts.Proxy}
 	}

-	var next selector.Next
+	// lookup the route to send the reques to
+	// TODO: move to internal lookup func
+	routes, err := g.opts.Lookup(ctx, req, callOpts)
+	if err != nil {
+		return nil, errors.InternalServerError("go.micro.client", err.Error())
+	}
+
+	// balance the list of nodes
+	next, err := callOpts.Selector.Select(routes)
+	if err != nil {
+		return nil, err
+	}

 	call := func(i int) (client.Stream, error) {
 		// call backoff first. Someone may want an initial start delay
@ -632,29 +557,12 @@ func (g *grpcClient) Stream(ctx context.Context, req client.Request, opts ...cli
 			time.Sleep(t)
 		}

-		if next == nil {
-			var routes []string
-
-			// lookup the route to send the reques to
-			// TODO apply any filtering here
-			routes, err = g.opts.Lookup(ctx, req, callOpts)
-			if err != nil {
-				return nil, errors.InternalServerError("go.micro.client", err.Error())
-			}
-
-			// balance the list of nodes
-			next, err = callOpts.Selector.Select(routes)
-			if err != nil {
-				return nil, err
-			}
-		}
-
 		// get the next node
 		node := next()

 		// make the call
 		stream := &grpcStream{}
-		err = gstream(ctx, node, req, stream, callOpts)
+		err = g.stream(ctx, node, req, stream, callOpts)

 		// record the result of the call to inform future routing decisions
 		if verr := g.opts.Selector.Record(node, err); verr != nil {
@ -666,10 +574,7 @@ func (g *grpcClient) Stream(ctx context.Context, req client.Request, opts ...cli
 			return nil, verr
 		}

-		if rerr := g.opts.Selector.Record(node, err); rerr != nil {
-			return nil, rerr
-		}
-
+		g.opts.Selector.Record(node, err)
 		return stream, err
 	}

@ -712,135 +617,119 @@ func (g *grpcClient) Stream(ctx context.Context, req client.Request, opts ...cli
 	return nil, grr
 }

-func (g *grpcClient) BatchPublish(ctx context.Context, ps []client.Message, opts ...client.PublishOption) error {
-	return g.publish(ctx, ps, opts...)
-}
-
 func (g *grpcClient) Publish(ctx context.Context, p client.Message, opts ...client.PublishOption) error {
-	return g.publish(ctx, []client.Message{p}, opts...)
-}
-
-func (g *grpcClient) publish(ctx context.Context, ps []client.Message, opts ...client.PublishOption) error {
+	var options client.PublishOptions
 	var body []byte

-	options := client.NewPublishOptions(opts...)
-
-	// get proxy
-	exchange := ""
-	if v, ok := os.LookupEnv("MICRO_PROXY"); ok {
-		exchange = v
+	// fail early on connect error
+	if !g.once.Load().(bool) {
+		if err := g.opts.Broker.Connect(); err != nil {
+			return errors.InternalServerError("go.micro.client", err.Error())
+		}
+		g.once.Store(true)
 	}

-	msgs := make([]*broker.Message, 0, len(ps))
+	for _, o := range opts {
+		o(&options)
+	}

-	omd, ok := metadata.FromOutgoingContext(ctx)
+	md, ok := metadata.FromContext(ctx)
 	if !ok {
-		omd = metadata.New(2)
+		md = make(map[string]string)
+	}
+	md["Content-Type"] = p.ContentType()
+	md["Micro-Topic"] = p.Topic()
+
+	// passed in raw data
+	if d, ok := p.Payload().(*raw.Frame); ok {
+		body = d.Data
+	} else {
+		// use codec for payload
+		cf, err := g.newGRPCCodec(p.ContentType())
+		if err != nil {
+			return errors.InternalServerError("go.micro.client", err.Error())
+		}
+		// set the body
+		b, err := cf.Marshal(p.Payload())
+		if err != nil {
+			return errors.InternalServerError("go.micro.client", err.Error())
+		}
+		body = b
 	}

-	for _, p := range ps {
-		md := metadata.Copy(omd)
-		md[metadata.HeaderContentType] = p.ContentType()
+	topic := p.Topic()

-		// passed in raw data
-		if d, ok := p.Payload().(*codec.Frame); ok {
-			body = d.Data
-		} else {
-			// use codec for payload
-			cf, err := g.newCodec(p.ContentType())
-			if err != nil {
-				return errors.InternalServerError("go.micro.client", err.Error())
-			}
-			// set the body
-			b, err := cf.Marshal(p.Payload())
-			if err != nil {
-				return errors.InternalServerError("go.micro.client", err.Error())
-			}
-			body = b
-		}
-
-		topic := p.Topic()
-		if len(exchange) > 0 {
-			topic = exchange
-		}
-
-		for k, v := range p.Metadata() {
-			md.Set(k, v)
-		}
-		md.Set(metadata.HeaderTopic, topic)
-		msgs = append(msgs, &broker.Message{Header: md, Body: body})
+	// get the exchange
+	if len(options.Exchange) > 0 {
+		topic = options.Exchange
 	}

-	return g.opts.Broker.BatchPublish(ctx, msgs,
-		broker.PublishContext(options.Context),
-		broker.PublishBodyOnly(options.BodyOnly),
-	)
+	return g.opts.Broker.Publish(topic, &broker.Message{
+		Header: md,
+		Body:   body,
+	}, broker.PublishContext(options.Context))
 }

 func (g *grpcClient) String() string {
 	return "grpc"
 }

-func (g *grpcClient) Name() string {
-	return g.opts.Name
-}
-
-func (g *grpcClient) getGrpcDialOptions(ctx context.Context) []grpc.DialOption {
-	var opts []grpc.DialOption
-
-	if g.opts.CallOptions.Context != nil {
-		if v := g.opts.CallOptions.Context.Value(grpcDialOptions{}); v != nil {
-			if vopts, ok := v.([]grpc.DialOption); ok {
-				opts = append(opts, vopts...)
-			}
-		}
+func (g *grpcClient) getGrpcDialOptions() []grpc.DialOption {
+	if g.opts.CallOptions.Context == nil {
+		return nil
 	}

-	if ctx != nil {
-		if v := ctx.Value(grpcDialOptions{}); v != nil {
-			if vopts, ok := v.([]grpc.DialOption); ok {
-				opts = append(opts, vopts...)
-			}
-		}
+	v := g.opts.CallOptions.Context.Value(grpcDialOptions{})
+
+	if v == nil {
+		return nil
+	}
+
+	opts, ok := v.([]grpc.DialOption)
+
+	if !ok {
+		return nil
 	}

 	return opts
 }

-func (g *grpcClient) getGrpcCallOptions(ctx context.Context) []grpc.CallOption {
-	var opts []grpc.CallOption
-
-	if g.opts.CallOptions.Context != nil {
-		if v := g.opts.CallOptions.Context.Value(grpcCallOptions{}); v != nil {
-			if vopts, ok := v.([]grpc.CallOption); ok {
-				opts = append(opts, vopts...)
-			}
-		}
+func (g *grpcClient) getGrpcCallOptions() []grpc.CallOption {
+	if g.opts.CallOptions.Context == nil {
+		return nil
 	}

-	if ctx != nil {
-		if v := ctx.Value(grpcCallOptions{}); v != nil {
-			if vopts, ok := v.([]grpc.CallOption); ok {
-				opts = append(opts, vopts...)
-			}
-		}
+	v := g.opts.CallOptions.Context.Value(grpcCallOptions{})
+
+	if v == nil {
+		return nil
+	}
+
+	opts, ok := v.([]grpc.CallOption)
+
+	if !ok {
+		return nil
 	}

 	return opts
 }

-func NewClient(opts ...client.Option) client.Client {
-	options := client.NewOptions(opts...)
+func newClient(opts ...client.Option) client.Client {
+	options := client.NewOptions()
 	// default content type for grpc
-	if options.ContentType == "" {
-		options.ContentType = DefaultContentType
+	options.ContentType = "application/grpc+proto"
+
+	for _, o := range opts {
+		o(&options)
 	}

 	rc := &grpcClient{
 		opts: options,
 	}
+	rc.once.Store(false)
+
+	rc.pool = newPool(options.PoolSize, options.PoolTTL, rc.poolMaxIdle(), rc.poolMaxStreams())

-	rc.pool = NewConnPool(options.PoolSize, options.PoolTTL, rc.poolMaxIdle(), rc.poolMaxStreams())
 	c := client.Client(rc)

 	// wrap in reverse
@ -848,17 +737,25 @@ func NewClient(opts ...client.Option) client.Client {
 		c = options.Wrappers[i-1](c)
 	}

+	rc.codecs = make(map[string]encoding.Codec, len(defaultGRPCCodecs))
+	for k, v := range defaultGRPCCodecs {
+		rc.codecs[k] = v
+	}
+
+	var codecs map[string]encoding.Codec
 	if rc.opts.Context != nil {
-		if codecs, ok := rc.opts.Context.Value(codecsKey{}).(map[string]encoding.Codec); ok && codecs != nil {
-			for k, v := range codecs {
-				rc.opts.Codecs[k] = &wrapGrpcCodec{v}
-			}
+		if v := rc.opts.Context.Value(codecsKey{}); v != nil {
+			codecs = v.(map[string]encoding.Codec)
 		}
 	}

-	for _, k := range options.Codecs {
-		encoding.RegisterCodec(&wrapMicroCodec{k})
+	for k, v := range codecs {
+		rc.codecs[k] = v
 	}

 	return c
 }
+
+func NewClient(opts ...client.Option) client.Client {
+	return newClient(opts...)
+}
--- a/grpc_pool.go
+++ b/grpc_pool.go
@ -2,7 +2,6 @@ package grpc

 import (
 	"context"
-	"strings"
 	"sync"
 	"time"

@ -10,47 +9,56 @@ import (
 	"google.golang.org/grpc/connectivity"
 )

-type ConnPool struct {
-	conns      map[string]*streamsPool
-	size       int
-	ttl        int64
+type pool struct {
+	size int
+	ttl  int64
+
+	//  max streams on a *poolConn
 	maxStreams int
-	maxIdle    int
+	//  max idle conns
+	maxIdle int
+
 	sync.Mutex
+	conns map[string]*streamsPool
 }

 type streamsPool struct {
 	//  head of list
-	head *PoolConn
+	head *poolConn
 	//  busy conns list
-	busy *PoolConn
+	busy *poolConn
 	//  the siza of list
 	count int
 	//  idle conn
 	idle int
 }

-type PoolConn struct {
-	err error
+type poolConn struct {
+	//  grpc conn
 	*grpc.ClientConn
-	next    *PoolConn
-	pool    *ConnPool
+	err  error
+	addr string
+
+	//  pool and streams pool
+	pool    *pool
 	sp      *streamsPool
-	pre     *PoolConn
-	addr    string
 	streams int
 	created int64
-	in      bool
+
+	//  list
+	pre  *poolConn
+	next *poolConn
+	in   bool
 }

-func NewConnPool(size int, ttl time.Duration, idle int, ms int) *ConnPool {
+func newPool(size int, ttl time.Duration, idle int, ms int) *pool {
 	if ms <= 0 {
 		ms = 1
 	}
 	if idle < 0 {
 		idle = 0
 	}
-	return &ConnPool{
+	return &pool{
 		size:       size,
 		ttl:        int64(ttl.Seconds()),
 		maxStreams: ms,
@ -59,15 +67,12 @@ func NewConnPool(size int, ttl time.Duration, idle int, ms int) *ConnPool {
 	}
 }

-func (p *ConnPool) Get(ctx context.Context, addr string, opts ...grpc.DialOption) (*PoolConn, error) {
-	if strings.HasPrefix(addr, "http") {
-		addr = addr[strings.Index(addr, ":")+3:]
-	}
+func (p *pool) getConn(ctx context.Context, addr string, opts ...grpc.DialOption) (*poolConn, error) {
 	now := time.Now().Unix()
 	p.Lock()
 	sp, ok := p.conns[addr]
 	if !ok {
-		sp = &streamsPool{head: &PoolConn{}, busy: &PoolConn{}, count: 0, idle: 0}
+		sp = &streamsPool{head: &poolConn{}, busy: &poolConn{}, count: 0, idle: 0}
 		p.conns[addr] = sp
 	}
 	//  while we have conns check streams and then return one
@ -130,12 +135,12 @@ func (p *ConnPool) Get(ctx context.Context, addr string, opts ...grpc.DialOption
 	}
 	p.Unlock()

-	//  create new conn)
+	//  create new conn
 	cc, err := grpc.DialContext(ctx, addr, opts...)
 	if err != nil {
 		return nil, err
 	}
-	conn = &PoolConn{ClientConn: cc, err: nil, addr: addr, pool: p, sp: sp, streams: 1, created: time.Now().Unix(), pre: nil, next: nil, in: false}
+	conn = &poolConn{cc, nil, addr, p, sp, 1, time.Now().Unix(), nil, nil, false}

 	//  add conn to streams pool
 	p.Lock()
@ -147,7 +152,7 @@ func (p *ConnPool) Get(ctx context.Context, addr string, opts ...grpc.DialOption
 	return conn, nil
 }

-func (p *ConnPool) Put(conn *PoolConn, err error) {
+func (p *pool) release(addr string, conn *poolConn, err error) {
 	p.Lock()
 	p, sp, created := conn.pool, conn.sp, conn.created
 	//  try to add conn
@ -180,13 +185,14 @@ func (p *ConnPool) Put(conn *PoolConn, err error) {
 		sp.idle++
 	}
 	p.Unlock()
+	return
 }

-func (conn *PoolConn) Close() {
-	conn.pool.Put(conn, conn.err)
+func (conn *poolConn) Close() {
+	conn.pool.release(conn.addr, conn, conn.err)
 }

-func removeConn(conn *PoolConn) {
+func removeConn(conn *poolConn) {
 	if conn.pre != nil {
 		conn.pre.next = conn.next
 	}
@ -197,9 +203,10 @@ func removeConn(conn *PoolConn) {
 	conn.next = nil
 	conn.in = false
 	conn.sp.count--
+	return
 }

-func addConnAfter(conn *PoolConn, after *PoolConn) {
+func addConnAfter(conn *poolConn, after *poolConn) {
 	conn.next = after.next
 	conn.pre = after
 	if after.next != nil {
@ -208,4 +215,5 @@ func addConnAfter(conn *PoolConn, after *PoolConn) {
 	after.next = conn
 	conn.in = true
 	conn.sp.count++
+	return
 }
--- a/message.go
+++ b/message.go
@ -1,19 +1,20 @@
 package grpc

 import (
-	"go.unistack.org/micro/v3/client"
-	"go.unistack.org/micro/v3/metadata"
+	"github.com/unistack-org/micro/v3/client"
 )

 type grpcEvent struct {
-	payload     interface{}
 	topic       string
 	contentType string
-	opts        client.MessageOptions
+	payload     interface{}
 }

 func newGRPCEvent(topic string, payload interface{}, contentType string, opts ...client.MessageOption) client.Message {
-	options := client.NewMessageOptions(opts...)
+	var options client.MessageOptions
+	for _, o := range opts {
+		o(&options)
+	}

 	if len(options.ContentType) > 0 {
 		contentType = options.ContentType
@ -23,7 +24,6 @@ func newGRPCEvent(topic string, payload interface{}, contentType string, opts ..
 		payload:     payload,
 		topic:       topic,
 		contentType: contentType,
-		opts:        options,
 	}
 }

@ -38,7 +38,3 @@ func (g *grpcEvent) Topic() string {
 func (g *grpcEvent) Payload() interface{} {
 	return g.payload
 }
-
-func (g *grpcEvent) Metadata() metadata.Metadata {
-	return g.opts.Metadata
-}
--- a/options.go
+++ b/options.go
@ -3,14 +3,15 @@ package grpc

 import (
 	"context"
+	"crypto/tls"

-	"go.unistack.org/micro/v3/client"
+	"github.com/unistack-org/micro/v3/client"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/encoding"
 )

 var (
-	// DefaultPoolMaxStreams maximum streams on a connection
+	// DefaultPoolMaxStreams maximum streams on a connectioin
 	// (20)
 	DefaultPoolMaxStreams = 20

@ -25,12 +26,16 @@ var (
 	// DefaultMaxSendMsgSize maximum message that client can send
 	// (4 MB).
 	DefaultMaxSendMsgSize = 1024 * 1024 * 4
-
-	// DefaultServiceConfig enable load balancing
-	DefaultServiceConfig = `{"loadBalancingPolicy":"round_robin"}`
 )

 type poolMaxStreams struct{}
+type poolMaxIdle struct{}
+type codecsKey struct{}
+type tlsAuth struct{}
+type maxRecvMsgSizeKey struct{}
+type maxSendMsgSizeKey struct{}
+type grpcDialOptions struct{}
+type grpcCallOptions struct{}

 // maximum streams on a connectioin
 func PoolMaxStreams(n int) client.Option {
@ -42,8 +47,6 @@ func PoolMaxStreams(n int) client.Option {
 	}
 }

-type poolMaxIdle struct{}
-
 // maximum idle conns of a pool
 func PoolMaxIdle(d int) client.Option {
 	return func(o *client.Options) {
@ -54,8 +57,6 @@ func PoolMaxIdle(d int) client.Option {
 	}
 }

-type codecsKey struct{}
-
 // gRPC Codec to be used to encode/decode requests for a given content type
 func Codec(contentType string, c encoding.Codec) client.Option {
 	return func(o *client.Options) {
@ -71,9 +72,19 @@ func Codec(contentType string, c encoding.Codec) client.Option {
 	}
 }

-type maxRecvMsgSizeKey struct{}
+// AuthTLS should be used to setup a secure authentication using TLS
+func AuthTLS(t *tls.Config) client.Option {
+	return func(o *client.Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, tlsAuth{}, t)
+	}
+}

+//
 // MaxRecvMsgSize set the maximum size of message that client can receive.
+//
 func MaxRecvMsgSize(s int) client.Option {
 	return func(o *client.Options) {
 		if o.Context == nil {
@ -83,9 +94,9 @@ func MaxRecvMsgSize(s int) client.Option {
 	}
 }

-type maxSendMsgSizeKey struct{}
-
+//
 // MaxSendMsgSize set the maximum size of message that client can send.
+//
 func MaxSendMsgSize(s int) client.Option {
 	return func(o *client.Options) {
 		if o.Context == nil {
@ -95,9 +106,9 @@ func MaxSendMsgSize(s int) client.Option {
 	}
 }

-type grpcDialOptions struct{}
-
+//
 // DialOptions to be used to configure gRPC dial options
+//
 func DialOptions(opts ...grpc.DialOption) client.CallOption {
 	return func(o *client.CallOptions) {
 		if o.Context == nil {
@ -107,9 +118,9 @@ func DialOptions(opts ...grpc.DialOption) client.CallOption {
 	}
 }

-type grpcCallOptions struct{}
-
+//
 // CallOptions to be used to configure gRPC call options
+//
 func CallOptions(opts ...grpc.CallOption) client.CallOption {
 	return func(o *client.CallOptions) {
 		if o.Context == nil {
@ -118,14 +129,3 @@ func CallOptions(opts ...grpc.CallOption) client.CallOption {
 		o.Context = context.WithValue(o.Context, grpcCallOptions{}, opts)
 	}
 }
-
-type serviceConfigKey struct{}
-
-func ServiceConfig(str string) client.CallOption {
-	return func(options *client.CallOptions) {
-		if options.Context == nil {
-			options.Context = context.Background()
-		}
-		options.Context = context.WithValue(options.Context, serviceConfigKey{}, str)
-	}
-}
--- a/request.go
+++ b/request.go
@ -4,17 +4,17 @@ import (
 	"fmt"
 	"strings"

-	"go.unistack.org/micro/v3/client"
-	"go.unistack.org/micro/v3/codec"
+	"github.com/unistack-org/micro/v3/client"
+	"github.com/unistack-org/micro/v3/codec"
 )

 type grpcRequest struct {
-	request     interface{}
-	codec       codec.Codec
 	service     string
 	method      string
 	contentType string
+	request     interface{}
 	opts        client.RequestOptions
+	codec       codec.Codec
 }

 // service Struct.Method /service.Struct/Method
@ -38,12 +38,15 @@ func methodToGRPC(service, method string) string {
 	return fmt.Sprintf("/%s.%s/%s", service, mParts[0], mParts[1])
 }

-func newGRPCRequest(service, method string, request interface{}, contentType string, opts ...client.RequestOption) client.Request {
-	options := client.NewRequestOptions(opts...)
+func newGRPCRequest(service, method string, request interface{}, contentType string, reqOpts ...client.RequestOption) client.Request {
+	var opts client.RequestOptions
+	for _, o := range reqOpts {
+		o(&opts)
+	}

 	// set the content-type specified
-	if len(options.ContentType) > 0 {
-		contentType = options.ContentType
+	if len(opts.ContentType) > 0 {
+		contentType = opts.ContentType
 	}

 	return &grpcRequest{
@ -51,7 +54,7 @@ func newGRPCRequest(service, method string, request interface{}, contentType str
 		method:      method,
 		request:     request,
 		contentType: contentType,
-		opts:        options,
+		opts:        opts,
 	}
 }

@ -71,7 +74,7 @@ func (g *grpcRequest) Endpoint() string {
 	return g.method
 }

-func (g *grpcRequest) Codec() codec.Codec {
+func (g *grpcRequest) Codec() codec.Writer {
 	return g.codec
 }

--- a/response.go
+++ b/response.go
@ -3,39 +3,41 @@ package grpc
 import (
 	"strings"

-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/metadata"
+	"github.com/unistack-org/micro/v3/codec"
+	"github.com/unistack-org/micro-codec-bytes"
 	"google.golang.org/grpc"
+	"google.golang.org/grpc/encoding"
 )

 type response struct {
-	conn   *PoolConn
+	conn   *poolConn
 	stream grpc.ClientStream
-	codec  codec.Codec
+	codec  encoding.Codec
+	gcodec codec.Codec
 }

 // Read the response
-func (r *response) Codec() codec.Codec {
-	return r.codec
+func (r *response) Codec() codec.Reader {
+	return r.gcodec
 }

 // read the header
-func (r *response) Header() metadata.Metadata {
-	meta, err := r.stream.Header()
+func (r *response) Header() map[string]string {
+	md, err := r.stream.Header()
 	if err != nil {
-		return nil
+		return map[string]string{}
 	}
-	md := metadata.New(len(meta))
-	for k, v := range meta {
-		md.Set(k, strings.Join(v, ","))
+	hdr := make(map[string]string, len(md))
+	for k, v := range md {
+		hdr[k] = strings.Join(v, ",")
 	}
-	return md
+	return hdr
 }

 // Read the undecoded response
 func (r *response) Read() ([]byte, error) {
-	f := &codec.Frame{}
-	if err := r.codec.ReadBody(&wrapStream{r.stream}, f); err != nil {
+	f := &bytes.Frame{}
+	if err := r.gcodec.ReadBody(f); err != nil {
 		return nil, err
 	}
 	return f.Data, nil
--- a/stream.go
+++ b/stream.go
@ -5,21 +5,23 @@ import (
 	"io"
 	"sync"

-	"go.unistack.org/micro/v3/client"
+	"github.com/unistack-org/micro/v3/client"
 	"google.golang.org/grpc"
 )

 // Implements the streamer interface
 type grpcStream struct {
+	// embed so we can access if need be
 	grpc.ClientStream
-	context  context.Context
+
+	sync.RWMutex
+	closed   bool
 	err      error
+	conn     *poolConn
 	request  client.Request
 	response client.Response
+	context  context.Context
 	close    func(err error)
-	conn     *PoolConn
-	sync.RWMutex
-	closed bool
 }

 func (g *grpcStream) Context() context.Context {
@ -42,14 +44,6 @@ func (g *grpcStream) Send(msg interface{}) error {
 	return nil
 }

-func (g *grpcStream) SendMsg(msg interface{}) error {
-	if err := g.ClientStream.SendMsg(msg); err != nil {
-		g.setError(err)
-		return err
-	}
-	return nil
-}
-
 func (g *grpcStream) Recv(msg interface{}) (err error) {
 	defer g.setError(err)

@ -68,24 +62,6 @@ func (g *grpcStream) Recv(msg interface{}) (err error) {
 	return
 }

-func (g *grpcStream) RecvMsg(msg interface{}) (err error) {
-	defer g.setError(err)
-
-	if err = g.ClientStream.RecvMsg(msg); err != nil {
-		// #202 - inconsistent gRPC stream behavior
-		// the only way to tell if the stream is done is when we get a EOF on the Recv
-		// here we should close the underlying gRPC ClientConn
-		closeErr := g.Close()
-		if err == io.EOF && closeErr != nil {
-			err = closeErr
-		}
-
-		return err
-	}
-
-	return
-}
-
 func (g *grpcStream) Error() error {
 	g.RLock()
 	defer g.RUnlock()
@ -116,17 +92,3 @@ func (g *grpcStream) Close() error {
 	g.close(g.err)
 	return g.ClientStream.CloseSend()
 }
-
-func (g *grpcStream) CloseSend() error {
-	g.Lock()
-	defer g.Unlock()
-
-	if g.closed {
-		return nil
-	}
-
-	// close the connection
-	g.closed = true
-	g.close(g.err)
-	return g.ClientStream.CloseSend()
-}