add aws v4 signature support to go-experimental (#7326)

Author: wing328

modules/openapi-generator/src/main/resources/go-experimental/client.mustache

@@ -24,6 +24,10 @@ import (
 	"unicode/utf8"
 
 	"golang.org/x/oauth2"
+	{{#withAWSV4Signature}}
+	awsv4 "github.com/aws/aws-sdk-go/aws/signer/v4"
+	awscredentials "github.com/aws/aws-sdk-go/aws/credentials"
+	{{/withAWSV4Signature}}
 )
 
 var (
@@ -351,6 +355,25 @@ func (c *APIClient) prepareRequest(
 		if auth, ok := ctx.Value(ContextAccessToken).(string); ok {
 			localVarRequest.Header.Add("Authorization", "Bearer "+auth)
 		}
+
+		{{#withAWSV4Signature}}
+		// AWS Signature v4 Authentication
+		if auth, ok := ctx.Value(ContextAWSv4).(AWSv4); ok {
+			creds := awscredentials.NewStaticCredentials(auth.AccessKey, auth.SecretKey, "")
+			signer := awsv4.NewSigner(creds)
+			var reader *strings.Reader
+			if body == nil {
+				reader = strings.NewReader("")
+			} else {
+				reader = strings.NewReader(body.String())
+			}
+			timestamp := time.Now()
+			_, err := signer.Sign(localVarRequest, reader, "oapi", "eu-west-2", timestamp)
+			if err != nil {
+				return nil, err
+			}
+		}
+		{{/withAWSV4Signature}}
 	}
 
 	for header, value := range c.cfg.DefaultHeader {

modules/openapi-generator/src/main/resources/go-experimental/configuration.mustache

@@ -31,6 +31,11 @@ var (
 	// ContextAPIKeys takes a string apikey as authentication for the request
 	ContextAPIKeys = contextKey("apiKeys")
 
+	{{#withAWSV4Signature}}
+	// ContextAWSv4 takes an Access Key and a Secret Key for signing AWS Signature v4
+	ContextAWSv4 = contextKey("awsv4")
+
+	{{/withAWSV4Signature}}
 	// ContextHttpSignatureAuth takes HttpSignatureAuth as authentication for the request.
 	ContextHttpSignatureAuth = contextKey("httpsignature")
 
@@ -59,6 +64,15 @@ type APIKey struct {
 	Prefix string
 }
 
+{{#withAWSV4Signature}}
+// AWSv4 provides AWS Signature to a request passed via context using ContextAWSv4
+// https://docs.aws.amazon.com/general/latest/gr/signature-version-4.html
+type AWSv4 struct {
+	AccessKey string
+	SecretKey string
+}
+
+{{/withAWSV4Signature}}
 // ServerVariable stores the information about a server variable
 type ServerVariable struct {
 	Description  string

modules/openapi-generator/src/main/resources/go-experimental/go.mod.mustache

@@ -4,4 +4,7 @@ go 1.13
 
 require (
 	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45
+	{{#withAWSV4Signature}}
+	github.com/aws/aws-sdk-go v1.34.14
+	{{/withAWSV4Signature}}
 )

modules/openapi-generator/src/main/resources/go/go.mod.mustache

@@ -3,5 +3,7 @@ module {{gitHost}}/{{gitUserId}}/{{gitRepoId}}{{#isGoSubmodule}}/{{packageName}}
 require (
 	github.com/antihax/optional v1.0.0
 	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45
-	{{#withAWSV4Signature}}github.com/aws/aws-sdk-go v1.26.3{{/withAWSV4Signature}}
+	{{#withAWSV4Signature}}
+	github.com/aws/aws-sdk-go v1.34.14
+	{{/withAWSV4Signature}}
 )

samples/client/petstore/go-experimental/go-petstore/client.go

@@ -357,6 +357,7 @@ func (c *APIClient) prepareRequest(
 		if auth, ok := ctx.Value(ContextAccessToken).(string); ok {
 			localVarRequest.Header.Add("Authorization", "Bearer "+auth)
 		}
+
 	}
 
 	for header, value := range c.cfg.DefaultHeader {

samples/client/petstore/go/go-petstore-withXml/go.mod

@@ -3,5 +3,4 @@ module github.com/GIT_USER_ID/GIT_REPO_ID
 require (
 	github.com/antihax/optional v1.0.0
 	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45
-	
 )

samples/client/petstore/go/go-petstore/go.mod

@@ -3,5 +3,4 @@ module github.com/GIT_USER_ID/GIT_REPO_ID
 require (
 	github.com/antihax/optional v1.0.0
 	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45
-	
 )

samples/openapi3/client/extensions/x-auth-id-alias/go-experimental/client.go

@@ -342,6 +342,7 @@ func (c *APIClient) prepareRequest(
 		if auth, ok := ctx.Value(ContextAccessToken).(string); ok {
 			localVarRequest.Header.Add("Authorization", "Bearer "+auth)
 		}
+
 	}
 
 	for header, value := range c.cfg.DefaultHeader {

samples/openapi3/client/petstore/go-experimental/go-petstore/client.go

@@ -360,6 +360,7 @@ func (c *APIClient) prepareRequest(
 		if auth, ok := ctx.Value(ContextAccessToken).(string); ok {
 			localVarRequest.Header.Add("Authorization", "Bearer "+auth)
 		}
+
 	}
 
 	for header, value := range c.cfg.DefaultHeader {

samples/openapi3/client/petstore/go/go-petstore/go.mod

@@ -3,5 +3,4 @@ module github.com/GIT_USER_ID/GIT_REPO_ID
 require (
 	github.com/antihax/optional v1.0.0
 	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45
-	
 )