Updates SDK middleware values scoped to the stack being invoked

Updates the SDK's middleware metadata to be scoped to the individual
stack's execution. This ensures that operations invoked nested
within a stack will not be polluted with values from parent stack(s).

Fixes #914

aws/middleware/metadata.go

@@ -50,67 +50,103 @@ type (
 )
 
 // GetServiceID retrieves the service id from the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func GetServiceID(ctx context.Context) (v string) {
-	v, _ = ctx.Value(serviceIDKey{}).(string)
+	v, _ = middleware.GetStackValue(ctx, serviceIDKey{}).(string)
 	return v
 }
 
 // GetSigningName retrieves the service signing name from the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func GetSigningName(ctx context.Context) (v string) {
-	v, _ = ctx.Value(signingNameKey{}).(string)
+	v, _ = middleware.GetStackValue(ctx, signingNameKey{}).(string)
 	return v
 }
 
 // GetSigningRegion retrieves the region from the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func GetSigningRegion(ctx context.Context) (v string) {
-	v, _ = ctx.Value(signingRegionKey{}).(string)
+	v, _ = middleware.GetStackValue(ctx, signingRegionKey{}).(string)
 	return v
 }
 
 // GetRegion retrieves the endpoint region from the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func GetRegion(ctx context.Context) (v string) {
-	v, _ = ctx.Value(regionKey{}).(string)
+	v, _ = middleware.GetStackValue(ctx, regionKey{}).(string)
 	return v
 }
 
 // GetOperationName retrieves the service operation metadata from the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func GetOperationName(ctx context.Context) (v string) {
-	v, _ = ctx.Value(operationNameKey{}).(string)
+	v, _ = middleware.GetStackValue(ctx, operationNameKey{}).(string)
 	return v
 }
 
 // GetPartitionID retrieves the endpoint partition id from the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func GetPartitionID(ctx context.Context) string {
-	v, _ := ctx.Value(partitionIDKey{}).(string)
+	v, _ := middleware.GetStackValue(ctx, partitionIDKey{}).(string)
 	return v
 }
 
 // SetSigningName set or modifies the signing name on the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func SetSigningName(ctx context.Context, value string) context.Context {
-	return context.WithValue(ctx, signingNameKey{}, value)
+	return middleware.WithStackValue(ctx, signingNameKey{}, value)
 }
 
 // SetSigningRegion sets or modifies the region on the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func SetSigningRegion(ctx context.Context, value string) context.Context {
-	return context.WithValue(ctx, signingRegionKey{}, value)
+	return middleware.WithStackValue(ctx, signingRegionKey{}, value)
 }
 
 // SetServiceID sets the service id on the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func SetServiceID(ctx context.Context, value string) context.Context {
-	return context.WithValue(ctx, serviceIDKey{}, value)
+	return middleware.WithStackValue(ctx, serviceIDKey{}, value)
 }
 
 // setRegion sets the endpoint region on the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func setRegion(ctx context.Context, value string) context.Context {
-	return context.WithValue(ctx, regionKey{}, value)
+	return middleware.WithStackValue(ctx, regionKey{}, value)
 }
 
 // setOperationName sets the service operation on the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func setOperationName(ctx context.Context, value string) context.Context {
-	return context.WithValue(ctx, operationNameKey{}, value)
+	return middleware.WithStackValue(ctx, operationNameKey{}, value)
 }
 
 // SetPartitionID sets the partition id of a resolved region on the context
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func SetPartitionID(ctx context.Context, value string) context.Context {
-	return context.WithValue(ctx, partitionIDKey{}, value)
+	return middleware.WithStackValue(ctx, partitionIDKey{}, value)
 }

aws/retry/middleware.go

@@ -11,6 +11,7 @@ import (
 	awsmiddle "github.com/aws/aws-sdk-go-v2/aws/middleware"
 	"github.com/aws/aws-sdk-go-v2/internal/sdk"
 	"github.com/aws/smithy-go/logging"
+	"github.com/aws/smithy-go/middleware"
 	smithymiddle "github.com/aws/smithy-go/middleware"
 	"github.com/aws/smithy-go/transport/http"
 )
@@ -26,8 +27,6 @@ type retryMetadata struct {
 	AttemptClockSkew time.Duration
 }
 
-type retryMetadataKey struct{}
-
 // Attempt is a Smithy FinalizeMiddleware that handles retry attempts using the provided
 // Retryer implementation
 type Attempt struct {
@@ -191,14 +190,24 @@ func (r MetricsHeader) HandleFinalize(ctx context.Context, in smithymiddle.Final
 	return next.HandleFinalize(ctx, in)
 }
 
-// getRetryMetadata retrieves retryMetadata from the context and a bool indicating if it was set
+type retryMetadataKey struct{}
+
+// getRetryMetadata retrieves retryMetadata from the context and a bool
+// indicating if it was set.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func getRetryMetadata(ctx context.Context) (metadata retryMetadata, ok bool) {
-	metadata, ok = ctx.Value(retryMetadataKey{}).(retryMetadata)
+	metadata, ok = middleware.GetStackValue(ctx, retryMetadataKey{}).(retryMetadata)
 	return metadata, ok
 }
 
+// setRetryMetadata sets the retryMetadata on the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func setRetryMetadata(ctx context.Context, metadata retryMetadata) context.Context {
-	return context.WithValue(ctx, retryMetadataKey{}, metadata)
+	return middleware.WithStackValue(ctx, retryMetadataKey{}, metadata)
 }
 
 // AddRetryMiddlewaresOptions is the set of options that can be passed to AddRetryMiddlewares for configuring retry

aws/signer/v4/middleware.go

@@ -275,13 +275,18 @@ func haveCredentialProvider(p aws.CredentialsProvider) bool {
 type payloadHashKey struct{}
 
 // GetPayloadHash retrieves the payload hash to use for signing
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func GetPayloadHash(ctx context.Context) (v string) {
-	v, _ = ctx.Value(payloadHashKey{}).(string)
+	v, _ = middleware.GetStackValue(ctx, payloadHashKey{}).(string)
 	return v
 }
 
 // SetPayloadHash sets the payload hash to be used for signing the request
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func SetPayloadHash(ctx context.Context, hash string) context.Context {
-	ctx = context.WithValue(ctx, payloadHashKey{}, hash)
-	return ctx
+	return middleware.WithStackValue(ctx, payloadHashKey{}, hash)
 }

aws/signer/v4/middleware_test.go

@@ -52,8 +52,8 @@ func TestComputePayloadHashMiddleware(t *testing.T) {
 			c := &computePayloadSHA256{}
 
 			next := middleware.BuildHandlerFunc(func(ctx context.Context, in middleware.BuildInput) (out middleware.BuildOutput, metadata middleware.Metadata, err error) {
-				value, ok := ctx.Value(payloadHashKey{}).(string)
-				if !ok {
+				value := GetPayloadHash(ctx)
+				if len(value) == 0 {
 					t.Fatalf("expected payload hash value to be on context")
 				}
 				if e, a := tt.expectedHash, value; e != a {
@@ -175,7 +175,7 @@ func TestSignHTTPRequestMiddleware(t *testing.T) {
 			ctx = middleware.SetLogger(ctx, logger)
 
 			if len(tt.hash) != 0 {
-				ctx = context.WithValue(ctx, payloadHashKey{}, tt.hash)
+				ctx = SetPayloadHash(ctx, tt.hash)
 			}
 
 			_, _, err := c.HandleFinalize(ctx, middleware.FinalizeInput{

aws/signer/v4/presign_middleware_test.go

@@ -181,7 +181,7 @@ func TestPresignHTTPRequestMiddleware(t *testing.T) {
 			ctx = middleware.SetLogger(ctx, logger)
 
 			if len(c.PayloadHash) != 0 {
-				ctx = context.WithValue(ctx, payloadHashKey{}, c.PayloadHash)
+				ctx = SetPayloadHash(ctx, c.PayloadHash)
 			}
 
 			result, _, err := m.HandleFinalize(ctx, middleware.FinalizeInput{

go.mod

@@ -1,7 +1,7 @@
 module github.com/aws/aws-sdk-go-v2
 
 require (
-	github.com/aws/smithy-go v0.5.0
+	github.com/aws/smithy-go v0.5.1-0.20210106170010-b13567a94b97
 	github.com/google/go-cmp v0.5.4
 	github.com/jmespath/go-jmespath v0.4.0
 )

go.sum

@@ -1,5 +1,5 @@
-github.com/aws/smithy-go v0.5.0 h1:ArsdWUrb1n6/V/REXhuwq2TZv+kuqOBpMlGBd2EkDYM=
-github.com/aws/smithy-go v0.5.0/go.mod h1:EzMw8dbp/YJL4A5/sbhGddag+NPT7q084agLbB9LgIw=
+github.com/aws/smithy-go v0.5.1-0.20210106170010-b13567a94b97 h1:CYur6TiTXgezWGjb91FvVZqbzMm9U7GyRX28Hx/MmsI=
+github.com/aws/smithy-go v0.5.1-0.20210106170010-b13567a94b97/go.mod h1:EzMw8dbp/YJL4A5/sbhGddag+NPT7q084agLbB9LgIw=
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/google/go-cmp v0.4.1 h1:/exdXoGamhu5ONeUJH0deniYLWYvQwW66yvlfiiKTu0=

service/internal/presigned-url/context.go

@@ -1,22 +1,48 @@
 package presignedurl
 
-import "context"
+import (
+	"context"
 
-// WithIsPresigning adds the isPresigning sentinal value to a context to signal
+	"github.com/aws/smithy-go/middleware"
+)
+
+// WithIsPresigning adds the isPresigning sentinel value to a context to signal
 // that the middleware stack is using the presign flow.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func WithIsPresigning(ctx context.Context) context.Context {
-	return context.WithValue(ctx, isPresigning{}, true)
+	return middleware.WithStackValue(ctx, isPresigningKey{}, true)
 }
 
 // GetIsPresigning returns if the context contains the isPresigning sentinel
 // value for presigning flows.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func GetIsPresigning(ctx context.Context) bool {
-	v := ctx.Value(isPresigning{})
-	if v == nil {
-		return false
-	}
+	v, _ := middleware.GetStackValue(ctx, isPresigningKey{}).(bool)
+	return v
+}
+
+type isPresigningKey struct{}
 
-	return v.(bool)
+// AddAsIsPresigingMiddleware adds a middleware to the head of the stack that
+// will update the stack's context to be flagged as being invoked for the
+// purpose of presigning.
+func AddAsIsPresigingMiddleware(stack *middleware.Stack) error {
+	return stack.Initialize.Add(asIsPresigningMiddleware{}, middleware.Before)
 }
 
-type isPresigning struct{}
+type asIsPresigningMiddleware struct{}
+
+func (asIsPresigningMiddleware) ID() string { return "AsIsPresigningMiddleware" }
+
+func (asIsPresigningMiddleware) HandleInitialize(
+	ctx context.Context, in middleware.InitializeInput, next middleware.InitializeHandler,
+) (
+	out middleware.InitializeOutput, metadata middleware.Metadata, err error,
+) {
+	ctx = WithIsPresigning(ctx)
+	return next.HandleInitialize(ctx, in)
+}

service/internal/presigned-url/go.mod

@@ -4,7 +4,7 @@ go 1.15
 
 require (
 	github.com/aws/aws-sdk-go-v2 v0.31.0
-	github.com/aws/smithy-go v0.5.0
+	github.com/aws/smithy-go v0.5.1-0.20210106170010-b13567a94b97
 	github.com/google/go-cmp v0.5.4
 )
 

service/internal/presigned-url/go.sum

@@ -1,5 +1,5 @@
-github.com/aws/smithy-go v0.5.0 h1:ArsdWUrb1n6/V/REXhuwq2TZv+kuqOBpMlGBd2EkDYM=
-github.com/aws/smithy-go v0.5.0/go.mod h1:EzMw8dbp/YJL4A5/sbhGddag+NPT7q084agLbB9LgIw=
+github.com/aws/smithy-go v0.5.1-0.20210106170010-b13567a94b97 h1:CYur6TiTXgezWGjb91FvVZqbzMm9U7GyRX28Hx/MmsI=
+github.com/aws/smithy-go v0.5.1-0.20210106170010-b13567a94b97/go.mod h1:EzMw8dbp/YJL4A5/sbhGddag+NPT7q084agLbB9LgIw=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/google/go-cmp v0.4.1 h1:/exdXoGamhu5ONeUJH0deniYLWYvQwW66yvlfiiKTu0=
 github.com/google/go-cmp v0.4.1/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=

service/internal/s3shared/arn_lookup.go

@@ -52,16 +52,22 @@ func (m *ARNLookup) HandleInitialize(ctx context.Context, in middleware.Initiali
 
 // arnResourceKey is the key set on context used to identify, retrive an ARN resource
 // if present on the context.
-type arnResourceKey struct {
-}
+type arnResourceKey struct{}
 
-// SetARNResourceOnContext sets arn on context
+// SetARNResourceOnContext sets the S3 ARN on the context.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func setARNResourceOnContext(ctx context.Context, value arn.ARN) context.Context {
-	return context.WithValue(ctx, arnResourceKey{}, value)
+	return middleware.WithStackValue(ctx, arnResourceKey{}, value)
 }
 
-// GetARNResourceFromContext returns an ARN from context and a bool indicating presence of ARN on ctx
+// GetARNResourceFromContext returns an ARN from context and a bool indicating
+// presence of ARN on ctx.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func GetARNResourceFromContext(ctx context.Context) (arn.ARN, bool) {
-	v, ok := ctx.Value(arnResourceKey{}).(arn.ARN)
+	v, ok := middleware.GetStackValue(ctx, arnResourceKey{}).(arn.ARN)
 	return v, ok
 }

service/internal/s3shared/go.mod

@@ -4,7 +4,7 @@ go 1.15
 
 require (
 	github.com/aws/aws-sdk-go-v2 v0.31.0
-	github.com/aws/smithy-go v0.5.0
+	github.com/aws/smithy-go v0.5.1-0.20210106170010-b13567a94b97
 )
 
 replace github.com/aws/aws-sdk-go-v2 => ../../../

service/internal/s3shared/go.sum

@@ -1,5 +1,5 @@
-github.com/aws/smithy-go v0.5.0 h1:ArsdWUrb1n6/V/REXhuwq2TZv+kuqOBpMlGBd2EkDYM=
-github.com/aws/smithy-go v0.5.0/go.mod h1:EzMw8dbp/YJL4A5/sbhGddag+NPT7q084agLbB9LgIw=
+github.com/aws/smithy-go v0.5.1-0.20210106170010-b13567a94b97 h1:CYur6TiTXgezWGjb91FvVZqbzMm9U7GyRX28Hx/MmsI=
+github.com/aws/smithy-go v0.5.1-0.20210106170010-b13567a94b97/go.mod h1:EzMw8dbp/YJL4A5/sbhGddag+NPT7q084agLbB9LgIw=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/google/go-cmp v0.4.1 h1:/exdXoGamhu5ONeUJH0deniYLWYvQwW66yvlfiiKTu0=
 github.com/google/go-cmp v0.4.1/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=

service/internal/s3shared/metadata.go

@@ -2,19 +2,27 @@ package s3shared
 
 import (
 	"context"
+
+	"github.com/aws/smithy-go/middleware"
 )
 
 // clonedInputKey used to denote if request input was cloned.
 type clonedInputKey struct{}
 
-// SetClonedInputKey sets a key on context to denote input was cloned previously
+// SetClonedInputKey sets a key on context to denote input was cloned previously.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func SetClonedInputKey(ctx context.Context, value bool) context.Context {
-	return context.WithValue(ctx, clonedInputKey{}, value)
+	return middleware.WithStackValue(ctx, clonedInputKey{}, value)
 }
 
 // IsClonedInput retrieves if context key for cloned input was set.
 // If set, we can infer that the reuqest input was cloned previously.
+//
+// Scoped to stack values. Use github.com/aws/smithy-go/middleware#ClearStackValues
+// to clear all stack values.
 func IsClonedInput(ctx context.Context) bool {
-	v, _ := ctx.Value(clonedInputKey{}).(bool)
+	v, _ := middleware.GetStackValue(ctx, clonedInputKey{}).(bool)
 	return v
 }