protoc-gen-go-micro/openapiv3.go
Vasiliy Tolstov f814b489db update
Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>
2021-10-27 15:29:48 +03:00

690 lines
21 KiB
Go

// Copyright 2020 Google LLC. All Rights Reserved.
//
// 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.
//
package main
import (
"fmt"
"log"
"net/http"
"regexp"
"sort"
"strings"
annotations "go.unistack.org/micro-proto/v3/api"
v3 "go.unistack.org/micro-proto/v3/openapiv3"
"google.golang.org/protobuf/compiler/protogen"
jsonpb "google.golang.org/protobuf/encoding/protojson"
"google.golang.org/protobuf/proto"
"google.golang.org/protobuf/reflect/protoreflect"
)
type openapiv3Generator struct {
plugin *protogen.Plugin
requiredSchemas []string // Names of schemas that need to be generated.
generatedSchemas []string // Names of schemas that have already been generated.
linterRulePattern *regexp.Regexp
namePattern *regexp.Regexp
}
func (g *Generator) openapiv3Generate(component string, plugin *protogen.Plugin) error {
og := &openapiv3Generator{
plugin: plugin,
requiredSchemas: make([]string, 0),
generatedSchemas: make([]string, 0),
linterRulePattern: regexp.MustCompile(`\(-- .* --\)`),
namePattern: regexp.MustCompile("{(.*)=(.*)}"),
}
d := og.buildDocumentV3(plugin)
bytes, err := (jsonpb.MarshalOptions{Indent: " "}).Marshal(d)
if err != nil {
return fmt.Errorf("failed to marshal: %s", err.Error())
}
outputFile := og.plugin.NewGeneratedFile(g.openapiFile, "")
if _, err := outputFile.Write(bytes); err != nil {
return fmt.Errorf("failed to write: %s", err.Error())
}
return nil
}
// buildDocumentV3 builds an OpenAPIv3 document for a plugin request.
func (g *openapiv3Generator) buildDocumentV3(plugin *protogen.Plugin) *v3.Document {
d := &v3.Document{}
d.Openapi = "3.0.3"
d.Info = &v3.Info{
Title: "",
Version: "0.0.1",
Description: "",
}
for _, file := range plugin.Files {
if !proto.HasExtension(file.Desc.Options(), v3.E_Openapiv3Swagger) {
continue
}
ext := proto.GetExtension(file.Desc.Options(), v3.E_Openapiv3Swagger)
if ext == nil {
continue
}
if doc, ok := ext.(*v3.Document); ok && doc != nil {
if doc.Openapi != "" {
d.Openapi = doc.Openapi
}
d.Info = proto.Clone(doc.Info).(*v3.Info)
d.Servers = append(d.Servers, doc.Servers...)
}
}
d.Paths = &v3.Paths{}
d.Components = &v3.Components{
Schemas: &v3.SchemasOrReferences{
AdditionalProperties: []*v3.NamedSchemaOrReference{},
},
}
for _, file := range g.plugin.Files {
g.addPathsToDocumentV3(d, file)
}
for len(g.requiredSchemas) > 0 {
count := len(g.requiredSchemas)
for _, file := range g.plugin.Files {
g.addSchemasToDocumentV3(d, file)
}
g.requiredSchemas = g.requiredSchemas[count:len(g.requiredSchemas)]
}
// Sort the paths.
{
pairs := d.Paths.Path
sort.Slice(pairs, func(i, j int) bool {
return pairs[i].Name < pairs[j].Name
})
d.Paths.Path = pairs
}
// Sort the schemas.
{
pairs := d.Components.Schemas.AdditionalProperties
sort.Slice(pairs, func(i, j int) bool {
return pairs[i].Name < pairs[j].Name
})
d.Components.Schemas.AdditionalProperties = pairs
}
return d
}
// filterCommentString removes line breaks and linter rules from comments.
func (g *openapiv3Generator) filterCommentString(c protogen.Comments) string {
comment := string(c)
comment = strings.Replace(comment, "\n", "", -1)
comment = g.linterRulePattern.ReplaceAllString(comment, "")
return strings.TrimSpace(comment)
}
// addPathsToDocumentV3 adds paths from a specified file descriptor.
func (g *openapiv3Generator) addPathsToDocumentV3(d *v3.Document, file *protogen.File) {
for _, service := range file.Services {
comment := g.filterCommentString(service.Comments.Leading)
if d.Info.Title == "" {
d.Info.Title = service.GoName
}
if d.Info.Description == "" {
d.Info.Description = comment
}
for _, method := range service.Methods {
comment := g.filterCommentString(method.Comments.Leading)
inputMessage := method.Input
outputMessage := method.Output
operationID := service.GoName + "_" + method.GoName
eopt := proto.GetExtension(method.Desc.Options(), v3.E_Openapiv3Operation)
if eopt != nil && eopt != v3.E_Openapiv3Operation.InterfaceOf(v3.E_Openapiv3Operation.Zero()) {
opt := eopt.(*v3.Operation)
if opt.OperationId != "" {
operationID = opt.OperationId
}
}
xt := annotations.E_Http
extension := proto.GetExtension(method.Desc.Options(), xt)
var path string
var methodName string
var body string
if extension != nil && extension != xt.InterfaceOf(xt.Zero()) {
rule := extension.(*annotations.HttpRule)
body = rule.Body
switch pattern := rule.Pattern.(type) {
case *annotations.HttpRule_Get:
path = pattern.Get
methodName = "GET"
case *annotations.HttpRule_Post:
path = pattern.Post
methodName = "POST"
case *annotations.HttpRule_Put:
path = pattern.Put
methodName = "PUT"
case *annotations.HttpRule_Delete:
path = pattern.Delete
methodName = "DELETE"
case *annotations.HttpRule_Patch:
path = pattern.Patch
methodName = "PATCH"
case *annotations.HttpRule_Custom:
path = "custom-unsupported"
default:
path = "unknown-unsupported"
}
}
if methodName != "" {
op, path2 := g.buildOperationV3(
file, method, operationID, comment, path, body, inputMessage, outputMessage)
g.addOperationV3(d, op, path2, methodName)
}
}
}
}
// buildOperationV3 constructs an operation for a set of values.
func (g *openapiv3Generator) buildOperationV3(
file *protogen.File,
method *protogen.Method,
operationID string,
description string,
path string,
bodyField string,
inputMessage *protogen.Message,
outputMessage *protogen.Message,
) (*v3.Operation, string) {
// coveredParameters tracks the parameters that have been used in the body or path.
coveredParameters := make([]string, 0)
if bodyField != "" {
coveredParameters = append(coveredParameters, bodyField)
}
// Initialize the list of operation parameters.
parameters := []*v3.ParameterOrReference{}
// Build a list of header parameters.
eopt := proto.GetExtension(method.Desc.Options(), v3.E_Openapiv3Operation)
if eopt != nil && eopt != v3.E_Openapiv3Operation.InterfaceOf(v3.E_Openapiv3Operation.Zero()) {
opt := eopt.(*v3.Operation)
parameters = append(parameters, opt.Parameters...)
}
sparameters := make(map[string]struct{})
for _, paramOrRef := range parameters {
parameter := paramOrRef.GetParameter()
if parameter == nil {
continue
}
sparameters[parameter.Name] = struct{}{}
}
// Build a list of path parameters.
pathParameters := make([]string, 0)
if matches := g.namePattern.FindStringSubmatch(path); matches != nil {
// Add the "name=" "name" value to the list of covered parameters.
coveredParameters = append(coveredParameters, matches[1])
// Convert the path from the starred form to use named path parameters.
starredPath := matches[2]
parts := strings.Split(starredPath, "/")
// The starred path is assumed to be in the form "things/*/otherthings/*".
// We want to convert it to "things/{thing}/otherthings/{otherthing}".
for i := 0; i < len(parts)-1; i += 2 {
section := parts[i]
parameter := singular(section)
parts[i+1] = "{" + parameter + "}"
pathParameters = append(pathParameters, parameter)
}
// Rewrite the path to use the path parameters.
newPath := strings.Join(parts, "/")
path = strings.Replace(path, matches[0], newPath, 1)
}
// Add the path parameters to the operation parameters.
for _, pathParameter := range pathParameters {
if _, ok := sparameters[pathParameter]; ok {
continue
}
parameters = append(parameters,
&v3.ParameterOrReference{
Oneof: &v3.ParameterOrReference_Parameter{
Parameter: &v3.Parameter{
Name: pathParameter,
In: "path",
Required: true,
Description: "The " + pathParameter + " id.",
Schema: &v3.SchemaOrReference{
Oneof: &v3.SchemaOrReference_Schema{
Schema: &v3.Schema{
Type: "string",
},
},
},
},
},
})
}
// Add any unhandled fields in the request message as query parameters.
if bodyField != "*" {
for _, field := range inputMessage.Fields {
fieldName := string(field.Desc.Name())
if !contains(coveredParameters, fieldName) {
if _, ok := sparameters[fieldName]; ok {
continue
}
// Get the field description from the comments.
fieldDescription := g.filterCommentString(field.Comments.Leading)
parameters = append(parameters,
&v3.ParameterOrReference{
Oneof: &v3.ParameterOrReference_Parameter{
Parameter: &v3.Parameter{
Name: fieldName,
In: "query",
Description: fieldDescription,
Required: false,
Schema: &v3.SchemaOrReference{
Oneof: &v3.SchemaOrReference_Schema{
Schema: &v3.Schema{
Type: "string",
},
},
},
},
},
})
}
}
}
// Create the response.
responses := &v3.Responses{
ResponseOrReference: []*v3.NamedResponseOrReference{
&v3.NamedResponseOrReference{
Name: "200",
Value: &v3.ResponseOrReference{
Oneof: &v3.ResponseOrReference_Response{
Response: &v3.Response{
Description: "OK",
Content: g.responseContentForMessage(outputMessage),
},
},
},
},
},
}
// Create the operation.
op := &v3.Operation{
Summary: description,
OperationId: operationID,
Parameters: parameters,
Responses: responses,
}
// If a body field is specified, we need to pass a message as the request body.
if bodyField != "" {
var bodyFieldScalarTypeName string
var bodyFieldMessageTypeName string
if bodyField == "*" {
// Pass the entire request message as the request body.
bodyFieldMessageTypeName = g.fullMessageTypeName(inputMessage)
} else {
// If body refers to a message field, use that type.
for _, field := range inputMessage.Fields {
if string(field.Desc.Name()) == bodyField {
switch field.Desc.Kind() {
case protoreflect.StringKind:
bodyFieldScalarTypeName = "string"
case protoreflect.MessageKind:
bodyFieldMessageTypeName = g.fullMessageTypeName(field.Message)
default:
log.Printf("unsupported field type %+v", field.Desc)
}
break
}
}
}
var requestSchema *v3.SchemaOrReference
if bodyFieldScalarTypeName != "" {
requestSchema = &v3.SchemaOrReference{
Oneof: &v3.SchemaOrReference_Schema{
Schema: &v3.Schema{
Type: bodyFieldScalarTypeName,
},
},
}
} else if bodyFieldMessageTypeName != "" {
requestSchema = &v3.SchemaOrReference{
Oneof: &v3.SchemaOrReference_Reference{
Reference: &v3.Reference{
XRef: g.schemaReferenceForTypeName(bodyFieldMessageTypeName),
},
},
}
}
op.RequestBody = &v3.RequestBodyOrReference{
Oneof: &v3.RequestBodyOrReference_RequestBody{
RequestBody: &v3.RequestBody{
Required: true,
Content: &v3.MediaTypes{
AdditionalProperties: []*v3.NamedMediaType{
&v3.NamedMediaType{
Name: "application/json",
Value: &v3.MediaType{
Schema: requestSchema,
},
},
},
},
},
},
}
}
return op, path
}
// addOperationV3 adds an operation to the specified path/method.
func (g *openapiv3Generator) addOperationV3(d *v3.Document, op *v3.Operation, path string, methodName string) {
var selectedPathItem *v3.NamedPathItem
for _, namedPathItem := range d.Paths.Path {
if namedPathItem.Name == path {
selectedPathItem = namedPathItem
break
}
}
// If we get here, we need to create a path item.
if selectedPathItem == nil {
selectedPathItem = &v3.NamedPathItem{Name: path, Value: &v3.PathItem{}}
d.Paths.Path = append(d.Paths.Path, selectedPathItem)
}
// Set the operation on the specified method.
switch methodName {
case http.MethodGet:
selectedPathItem.Value.Get = op
case http.MethodPost:
selectedPathItem.Value.Post = op
case http.MethodPut:
selectedPathItem.Value.Put = op
case http.MethodDelete:
selectedPathItem.Value.Delete = op
case http.MethodPatch:
selectedPathItem.Value.Patch = op
}
}
// schemaReferenceForTypeName returns an OpenAPI JSON Reference to the schema that represents a type.
func (g *openapiv3Generator) schemaReferenceForTypeName(typeName string) string {
if !contains(g.requiredSchemas, typeName) {
g.requiredSchemas = append(g.requiredSchemas, typeName)
}
parts := strings.Split(typeName, ".")
lastPart := parts[len(parts)-1]
return "#/components/schemas/" + lastPart
}
// itemsItemForTypeName is a helper constructor.
func (g *openapiv3Generator) itemsItemForTypeName(typeName string) *v3.ItemsItem {
return &v3.ItemsItem{SchemaOrReference: []*v3.SchemaOrReference{&v3.SchemaOrReference{
Oneof: &v3.SchemaOrReference_Schema{
Schema: &v3.Schema{
Type: typeName,
},
},
}}}
}
// itemsItemForReference is a helper constructor.
func (g *openapiv3Generator) itemsItemForReference(xref string) *v3.ItemsItem {
return &v3.ItemsItem{SchemaOrReference: []*v3.SchemaOrReference{&v3.SchemaOrReference{
Oneof: &v3.SchemaOrReference_Reference{
Reference: &v3.Reference{
XRef: xref,
},
},
}}}
}
// fullMessageTypeName builds the full type name of a message.
func (g *openapiv3Generator) fullMessageTypeName(message *protogen.Message) string {
return "." + string(message.Desc.ParentFile().Package()) + "." + string(message.Desc.Name())
}
func (g *openapiv3Generator) responseContentForMessage(outputMessage *protogen.Message) *v3.MediaTypes {
typeName := g.fullMessageTypeName(outputMessage)
if typeName == ".google.protobuf.Empty" {
return &v3.MediaTypes{}
}
if typeName == ".google.api.HttpBody" || typeName == ".micro.codec.Frame" {
return &v3.MediaTypes{
AdditionalProperties: []*v3.NamedMediaType{
&v3.NamedMediaType{
Name: "application/octet-stream",
Value: &v3.MediaType{},
},
},
}
}
return &v3.MediaTypes{
AdditionalProperties: []*v3.NamedMediaType{
&v3.NamedMediaType{
Name: "application/json",
Value: &v3.MediaType{
Schema: &v3.SchemaOrReference{
Oneof: &v3.SchemaOrReference_Reference{
Reference: &v3.Reference{
XRef: g.schemaReferenceForTypeName(g.fullMessageTypeName(outputMessage)),
},
},
},
},
},
},
}
}
// addSchemasToDocumentV3 adds info from one file descriptor.
func (g *openapiv3Generator) addSchemasToDocumentV3(d *v3.Document, file *protogen.File) {
// For each message, generate a definition.
for _, message := range file.Messages {
typeName := g.fullMessageTypeName(message)
// Only generate this if we need it and haven't already generated it.
if !contains(g.requiredSchemas, typeName) ||
contains(g.generatedSchemas, typeName) {
continue
}
g.generatedSchemas = append(g.generatedSchemas, typeName)
// Get the message description from the comments.
messageDescription := g.filterCommentString(message.Comments.Leading)
// Build an array holding the fields of the message.
definitionProperties := &v3.Properties{
AdditionalProperties: make([]*v3.NamedSchemaOrReference, 0),
}
for _, field := range message.Fields {
// Check the field annotations to see if this is a readonly field.
outputOnly := false
extension := proto.GetExtension(field.Desc.Options(), annotations.E_FieldBehavior)
if extension != nil {
switch v := extension.(type) {
case []annotations.FieldBehavior:
for _, vv := range v {
if vv == annotations.FieldBehavior_OUTPUT_ONLY {
outputOnly = true
}
}
default:
log.Printf("unsupported extension type %T", extension)
}
}
// Get the field description from the comments.
fieldDescription := g.filterCommentString(field.Comments.Leading)
// The field is either described by a reference or a schema.
XRef := ""
fieldSchema := &v3.Schema{
Description: fieldDescription,
}
if outputOnly {
fieldSchema.ReadOnly = true
}
if field.Desc.IsList() {
fieldSchema.Type = "array"
switch field.Desc.Kind() {
case protoreflect.MessageKind:
fieldSchema.Items = g.itemsItemForReference(
g.schemaReferenceForTypeName(
g.fullMessageTypeName(field.Message)))
case protoreflect.StringKind:
fieldSchema.Items = g.itemsItemForTypeName("string")
case protoreflect.Int32Kind,
protoreflect.Sint32Kind,
protoreflect.Uint32Kind,
protoreflect.Int64Kind,
protoreflect.Sint64Kind,
protoreflect.Uint64Kind,
protoreflect.Sfixed32Kind,
protoreflect.Fixed32Kind,
protoreflect.Sfixed64Kind,
protoreflect.Fixed64Kind:
fieldSchema.Items = g.itemsItemForTypeName("integer")
case protoreflect.EnumKind:
fieldSchema.Items = g.itemsItemForTypeName("integer")
case protoreflect.BoolKind:
fieldSchema.Items = g.itemsItemForTypeName("boolean")
case protoreflect.FloatKind, protoreflect.DoubleKind:
fieldSchema.Items = g.itemsItemForTypeName("number")
case protoreflect.BytesKind:
fieldSchema.Items = g.itemsItemForTypeName("string")
default:
log.Printf("(TODO) Unsupported array type: %+v", g.fullMessageTypeName(field.Message))
}
} else if field.Desc.IsMap() &&
field.Desc.MapKey().Kind() == protoreflect.StringKind &&
field.Desc.MapValue().Kind() == protoreflect.StringKind {
fieldSchema.Type = "object"
} else {
k := field.Desc.Kind()
switch k {
case protoreflect.MessageKind:
typeName := g.fullMessageTypeName(field.Message)
switch typeName {
case ".google.protobuf.Timestamp":
// Timestamps are serialized as strings
fieldSchema.Type = "string"
fieldSchema.Format = "RFC3339"
case ".google.type.Date":
// Dates are serialized as strings
fieldSchema.Type = "string"
fieldSchema.Format = "date"
case ".google.type.DateTime":
// DateTimes are serialized as strings
fieldSchema.Type = "string"
fieldSchema.Format = "date-time"
default:
// The field is described by a reference.
XRef = g.schemaReferenceForTypeName(typeName)
}
case protoreflect.StringKind:
fieldSchema.Type = "string"
case protoreflect.Int32Kind,
protoreflect.Sint32Kind,
protoreflect.Uint32Kind,
protoreflect.Int64Kind,
protoreflect.Sint64Kind,
protoreflect.Uint64Kind,
protoreflect.Sfixed32Kind,
protoreflect.Fixed32Kind,
protoreflect.Sfixed64Kind,
protoreflect.Fixed64Kind:
fieldSchema.Type = "integer"
fieldSchema.Format = k.String()
case protoreflect.EnumKind:
fieldSchema.Type = "integer"
fieldSchema.Format = "enum"
case protoreflect.BoolKind:
fieldSchema.Type = "boolean"
case protoreflect.FloatKind, protoreflect.DoubleKind:
fieldSchema.Type = "number"
fieldSchema.Format = k.String()
case protoreflect.BytesKind:
fieldSchema.Type = "string"
fieldSchema.Format = "bytes"
default:
log.Printf("(TODO) Unsupported field type: %+v", g.fullMessageTypeName(field.Message))
}
}
var value *v3.SchemaOrReference
if XRef != "" {
value = &v3.SchemaOrReference{
Oneof: &v3.SchemaOrReference_Reference{
Reference: &v3.Reference{
XRef: XRef,
},
},
}
} else {
value = &v3.SchemaOrReference{
Oneof: &v3.SchemaOrReference_Schema{
Schema: fieldSchema,
},
}
}
definitionProperties.AdditionalProperties = append(
definitionProperties.AdditionalProperties,
&v3.NamedSchemaOrReference{
Name: string(field.Desc.Name()),
Value: value,
},
)
}
// Add the schema to the components.schema list.
d.Components.Schemas.AdditionalProperties = append(d.Components.Schemas.AdditionalProperties,
&v3.NamedSchemaOrReference{
Name: string(message.Desc.Name()),
Value: &v3.SchemaOrReference{
Oneof: &v3.SchemaOrReference_Schema{
Schema: &v3.Schema{
Description: messageDescription,
Properties: definitionProperties,
},
},
},
},
)
}
}
// contains returns true if an array contains a specified string.
func contains(s []string, e string) bool {
for _, a := range s {
if a == e {
return true
}
}
return false
}
// singular produces the singular form of a collection name.
func singular(plural string) string {
if strings.HasSuffix(plural, "ves") {
return strings.TrimSuffix(plural, "ves") + "f"
}
if strings.HasSuffix(plural, "ies") {
return strings.TrimSuffix(plural, "ies") + "y"
}
if strings.HasSuffix(plural, "s") {
return strings.TrimSuffix(plural, "s")
}
return plural
}