Rewrite the store interface (#1335)

* WIP store rewrite

* Fix memory store tests

* Store hard expiry times rather than duration!

* Clarify memory test

* Add limit to store interface

* Implement suffix option

* Don't return nils from noop store

* Fix syncmap

* Start fixing store service

* wip service and cache

* Use _ for special characters in cockroachdb namespace

* Improve cockroach namespace comment

* Use service name as default store namespace

* Fixes

* Implement Store Scope

* Start fixing etcd

* implement read and write with expiry and prefix

* Fix etcd tests

* Fix cockroach store

* Fix cloudflare interface

* Fix certmagic / cloudflare store

* comment lint

* cache isn't implemented yet

* Only prepare DB staements once

Co-authored-by: Ben Toogood <ben@micro.mu>
Co-authored-by: ben-toogood <bentoogood@gmail.com>

store/cache/cache.go

@@ -0,0 +1,39 @@
+package cache
+
+import (
+	"github.com/micro/go-micro/v2/store"
+	"github.com/pkg/errors"
+)
+
+// Cache implements a cache in front of a micro Store
+type Cache struct {
+	options store.Options
+	store.Store
+
+	stores []store.Store
+}
+
+// NewStore returns new cache
+func NewStore(opts ...store.Option) store.Store {
+	s := &Cache{
+		options: store.Options{},
+		stores:  []store.Store{},
+	}
+	for _, o := range opts {
+		o(&s.options)
+	}
+	return s
+}
+
+// Init initialises a new cache
+func (c *Cache) Init(opts ...store.Option) error {
+	for _, o := range opts {
+		o(&c.options)
+	}
+	for _, s := range c.stores {
+		if err := s.Init(); err != nil {
+			return errors.Wrapf(err, "Store %s failed to Init()", s.String())
+		}
+	}
+	return nil
+}

store/cache/cache_test.go

@@ -0,0 +1,15 @@
+package cache
+
+// import "testing"
+
+// func TestCache(t *testing.T) {
+// 	c := NewStore()
+// 	if err := c.Init(); err != nil {
+// 		//t.Fatal(err)
+// 	}
+// 	if results, err := c.Read("test"); err != nil {
+// 		//t.Fatal(err)
+// 	} else {
+// 		println(results)
+// 	}
+// }