add metrics APIs and corresponding otel adapter

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/GoWriter.java

@@ -101,6 +101,7 @@ private void init() {
         putContext("fmt.Errorf", SmithyGoDependency.FMT.func("Errorf"));
         putContext("errors.As", SmithyGoDependency.ERRORS.func("As"));
         putContext("context.Context", SmithyGoDependency.CONTEXT.func("Context"));
+        putContext("time.Now", SmithyGoDependency.TIME.func("Now"));
 
         if (!innerWriter) {
             packageDocs = new GoWriter(this.fullPackageName, true);

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/ServiceGenerator.java

@@ -26,7 +26,6 @@
 import java.util.Map;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
-import software.amazon.smithy.aws.traits.ServiceTrait;
 import software.amazon.smithy.codegen.core.SymbolProvider;
 import software.amazon.smithy.go.codegen.auth.AuthSchemeResolverGenerator;
 import software.amazon.smithy.go.codegen.auth.GetIdentityMiddlewareGenerator;
@@ -38,6 +37,7 @@
 import software.amazon.smithy.go.codegen.integration.ClientMemberResolver;
 import software.amazon.smithy.go.codegen.integration.ConfigFieldResolver;
 import software.amazon.smithy.go.codegen.integration.GoIntegration;
+import software.amazon.smithy.go.codegen.integration.OperationMetricsStruct;
 import software.amazon.smithy.go.codegen.integration.RuntimeClientPlugin;
 import software.amazon.smithy.model.Model;
 import software.amazon.smithy.model.knowledge.ServiceIndex;
@@ -95,7 +95,7 @@ public void run() {
     private GoWriter.Writable generate() {
         return GoWriter.ChainWritable.of(
                 generateMetadata(),
-                generateObservabilityHelpers(),
+                generateObservabilityComponents(),
                 generateClient(),
                 generateNew(),
                 generateGetOptions(),
@@ -105,16 +105,19 @@ private GoWriter.Writable generate() {
         ).compose();
     }
 
-    private GoWriter.Writable generateObservabilityHelpers() {
+    private GoWriter.Writable generateObservabilityComponents() {
         return goTemplate("""
+                $operationMetrics:W
+
                 func operationTracer(p $tracerProvider:T) $tracer:T {
                     return p.Tracer($scope:S)
                 }
                 """,
                 Map.of(
                         "tracerProvider", SmithyGoDependency.SMITHY_TRACING.interfaceSymbol("TracerProvider"),
                         "tracer", SmithyGoDependency.SMITHY_TRACING.interfaceSymbol("Tracer"),
-                        "scope", settings.getModuleName()
+                        "scope", settings.getModuleName(),
+                        "operationMetrics", new OperationMetricsStruct(settings.getModuleName())
                 ));
     }
 
@@ -339,8 +342,16 @@ func resolveAuthSchemes(options *Options) {
     @SuppressWarnings("checkstyle:LineLength")
     private GoWriter.Writable generateInvokeOperation() {
         return goTemplate("""
-                func (c *Client) invokeOperation(ctx $context.Context:T, opID string, params interface{}, optFns []func(*Options), stackFns ...func($stack:P, Options) error) (result interface{}, metadata $metadata:T, err error) {
-                    ctx = $clearStackValues:T(ctx)
+                $middleware:D $tracing:D
+                func (c *Client) invokeOperation(
+                    ctx context.Context, opID string, params interface{}, optFns []func(*Options), stackFns ...func(*middleware.Stack, Options) error,
+                ) (
+                    result interface{}, metadata middleware.Metadata, err error,
+                ) {
+                    ctx = middleware.ClearStackValues(ctx)
+                    ctx = middleware.WithServiceID(ctx, ServiceID)
+                    ctx = middleware.WithOperationName(ctx, opID)
+
                     $newStack:W
                     options := c.options.Copy()
                     $resolvers:W
@@ -363,24 +374,30 @@ private GoWriter.Writable generateInvokeOperation() {
                         }
                     }
 
+                    ctx, err = withOperationMetrics(ctx, options.MeterProvider)
+                    if err != nil {
+                        return nil, metadata, err
+                    }
+
                     tracer := operationTracer(options.TracerProvider)
-                    spanName := $fmt.Sprintf:T("$tracingServiceId:L.%s", opID)
+                    spanName := fmt.Sprintf("%s.%s", ServiceID, opID)
 
-                    ctx = $withOperationTracer:T(ctx, tracer)
+                    ctx = tracing.WithOperationTracer(ctx, tracer)
 
-                    ctx, span := tracer.StartSpan(ctx, spanName, func (o $spanOptions:P) {
-                        o.Kind = $spanKindClient:T
+                    ctx, span := tracer.StartSpan(ctx, spanName, func (o *tracing.SpanOptions) {
+                        o.Kind = tracing.SpanKindClient
                         o.Properties.Set("rpc.system", "aws-api")
                         o.Properties.Set("rpc.method", opID)
-                        o.Properties.Set("rpc.service", $tracingServiceId:S)
+                        o.Properties.Set("rpc.service", ServiceID)
                     })
+                    defer startMetricTimer(ctx, "client.call.duration")()
                     defer span.End()
 
                     handler := $newClientHandler:T(options.HTTPClient)
-                    decorated := $decorateHandler:T(handler, stack)
+                    decorated := middleware.DecorateHandler(handler, stack)
                     result, metadata, err = decorated.Handle(ctx, params)
                     if err != nil {
-                        span.SetProperty("error.go.type", $fmt.Sprintf:T("%T", err))
+                        span.SetProperty("error.go.type", fmt.Sprintf("%T", err))
                         span.SetProperty("error.go.error", err.Error())
 
                         var aerr smithy.APIError
@@ -399,18 +416,17 @@ private GoWriter.Writable generateInvokeOperation() {
 
                     span.SetProperty("error", err != nil)
                     if err == nil {
-                        span.SetStatus($spanStatusOK:T)
+                        span.SetStatus(tracing.SpanStatusOK)
                     } else {
-                        span.SetStatus($spanStatusError:T)
+                        span.SetStatus(tracing.SpanStatusError)
                     }
 
                     return result, metadata, err
                 }
                 """,
                 MapUtils.of(
-                        "stack", SmithyGoTypes.Middleware.Stack,
-                        "metadata", SmithyGoTypes.Middleware.Metadata,
-                        "clearStackValues", SmithyGoTypes.Middleware.ClearStackValues,
+                        "middleware", SmithyGoDependency.SMITHY_MIDDLEWARE,
+                        "tracing", SmithyGoDependency.SMITHY_TRACING,
                         "newStack", generateNewStack(),
                         "operationError", SmithyGoTypes.Smithy.OperationError,
                         "resolvers", GoWriter.ChainWritable.of(
@@ -425,16 +441,7 @@ private GoWriter.Writable generateInvokeOperation() {
                                         ConfigFieldResolver.Target.FINALIZATION
                                 ).map(this::generateConfigFieldResolver).toList()
                         ).compose(),
-                        "newClientHandler", SmithyGoDependency.SMITHY_HTTP_TRANSPORT.func("NewClientHandler"),
-                        "decorateHandler", SmithyGoDependency.SMITHY_MIDDLEWARE.func("DecorateHandler")
-                ),
-                Map.of(
-                        "tracingServiceId", getTracingServiceId(),
-                        "spanOptions", SmithyGoDependency.SMITHY_TRACING.struct("SpanOptions"),
-                        "spanKindClient", SmithyGoDependency.SMITHY_TRACING.constSymbol("SpanKindClient"),
-                        "withOperationTracer", SmithyGoDependency.SMITHY_TRACING.constSymbol("WithOperationTracer"),
-                        "spanStatusOK", SmithyGoDependency.SMITHY_TRACING.constSymbol("SpanStatusOK"),
-                        "spanStatusError", SmithyGoDependency.SMITHY_TRACING.constSymbol("SpanStatusError")
+                        "newClientHandler", SmithyGoDependency.SMITHY_HTTP_TRANSPORT.func("NewClientHandler")
                 ));
     }
 
@@ -497,10 +504,4 @@ func addProtocolFinalizerMiddlewares(stack $P, options $L, operation string) err
                         SignRequestMiddlewareGenerator.generateAddToProtocolFinalizers()
                 ).compose(false));
     }
-
-    private String getTracingServiceId() {
-        return service.hasTrait(ServiceTrait.class)
-                ? service.expectTrait(ServiceTrait.class).getSdkId().replaceAll("\\s", "")
-                : service.getId().getName();
-    }
 }

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/SmithyGoDependency.java

@@ -77,6 +77,7 @@ public final class SmithyGoDependency {
     public static final GoDependency SMITHY_ENDPOINTS = smithy("endpoints", "smithyendpoints");
     public static final GoDependency SMITHY_ENDPOINT_RULESFN = smithy("endpoints/private/rulesfn");
     public static final GoDependency SMITHY_TRACING = smithy("tracing");
+    public static final GoDependency SMITHY_METRICS = smithy("metrics");
 
     public static final GoDependency GO_JMESPATH = goJmespath(null);
     public static final GoDependency MATH = stdlib("math");

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/auth/GetIdentityMiddlewareGenerator.java

@@ -78,7 +78,13 @@ private GoWriter.Writable generateBody() {
                     return out, metadata, $fmt.Errorf:T("no identity resolver")
                 }
 
-                identity, err := resolver.GetIdentity(innerCtx, rscheme.IdentityProperties)
+                identity, err := timeOperationMetric(ctx, "client.call.resolve_identity_duration",
+                    func() ($identity:T, error) {
+                        return resolver.GetIdentity(innerCtx, rscheme.IdentityProperties)
+                    },
+                    func (o $recordMetricOptions:P) {
+                        o.Properties.Set("auth.scheme_id", rscheme.Scheme.SchemeID())
+                    })
                 if err != nil {
                     return out, metadata, $fmt.Errorf:T("get identity: %w", err)
                 }
@@ -89,7 +95,9 @@ private GoWriter.Writable generateBody() {
                 return next.HandleFinalize(ctx, in)
                 """,
                 MapUtils.of(
-                        "startSpan", SmithyGoDependency.SMITHY_TRACING.func("StartSpan")
+                        "startSpan", SmithyGoDependency.SMITHY_TRACING.func("StartSpan"),
+                        "identity", SmithyGoDependency.SMITHY_AUTH.interfaceSymbol("Identity"),
+                        "recordMetricOptions", SmithyGoDependency.SMITHY_METRICS.struct("RecordMetricOptions")
                 ));
     }
 

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/auth/SignRequestMiddlewareGenerator.java

@@ -86,7 +86,12 @@ private GoWriter.Writable generateBody() {
                     return out, metadata, $fmt.Errorf:T("no signer")
                 }
 
-                if err := signer.SignRequest(ctx, req, identity, rscheme.SignerProperties); err != nil {
+                _, err = timeOperationMetric(ctx, "client.call.signing_duration", func() (any, error) {
+                    return nil, signer.SignRequest(ctx, req, identity, rscheme.SignerProperties)
+                }, func(o $recordMetricOptions:P) {
+                    o.Properties.Set("auth.scheme_id", rscheme.Scheme.SchemeID())
+                })
+                if err != nil {
                     return out, metadata, $fmt.Errorf:T("sign request: %w", err)
                 }
 
@@ -96,7 +101,8 @@ private GoWriter.Writable generateBody() {
                 MapUtils.of(
                         // FUTURE(#458) protocol generator should specify the transport type
                         "request", SmithyGoTypes.Transport.Http.Request,
-                        "startSpan", SmithyGoDependency.SMITHY_TRACING.func("StartSpan")
+                        "startSpan", SmithyGoDependency.SMITHY_TRACING.func("StartSpan"),
+                        "recordMetricOptions", SmithyGoDependency.SMITHY_METRICS.struct("RecordMetricOptions")
                 ));
     }
 }

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/endpoints/EndpointMiddlewareGenerator.java

@@ -133,9 +133,12 @@ private GoWriter.Writable generateAssertResolver() {
     private GoWriter.Writable generateResolveEndpoint() {
         return goTemplate("""
                 params := bindEndpointParams(ctx, getOperationInput(ctx), m.options)
-                endpt, err := m.options.EndpointResolverV2.ResolveEndpoint(ctx, *params)
+                endpt, err := timeOperationMetric(ctx, "client.call.resolve_endpoint_duration",
+                    func() (smithyendpoints.Endpoint, error) {
+                        return m.options.EndpointResolverV2.ResolveEndpoint(ctx, *params)
+                    })
                 if err != nil {
-                    return out, metadata, $1T("failed to resolve service endpoint, %w", err)
+                    return out, metadata, $fmt.Errorf:T("failed to resolve service endpoint, %w", err)
                 }
 
                 span.SetProperty("operation.resolved_endpoint", endpt.URI.String())
@@ -145,13 +148,12 @@ private GoWriter.Writable generateResolveEndpoint() {
                 }
                 req.URL.Scheme = endpt.URI.Scheme
                 req.URL.Host = endpt.URI.Host
-                req.URL.Path = $2T(endpt.URI.Path, req.URL.Path)
-                req.URL.RawPath = $2T(endpt.URI.RawPath, req.URL.RawPath)
+                req.URL.Path = $1T(endpt.URI.Path, req.URL.Path)
+                req.URL.RawPath = $1T(endpt.URI.RawPath, req.URL.RawPath)
                 for k := range endpt.Headers {
                     req.Header.Set(k, endpt.Headers.Get(k))
                 }
                 """,
-                GoStdlibTypes.Fmt.Errorf,
                 SmithyGoTypes.Transport.Http.JoinPath);
     }
 

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/integration/HttpBindingProtocolGenerator.java

@@ -254,6 +254,8 @@ private void generateOperationSerializerMiddleware(GenerationContext context, Op
 
             writer.write(goTemplate("""
                     _, span := $T(ctx, "OperationSerializer")
+                    endTimer := startMetricTimer(ctx, "client.call.serialization_duration")
+                    defer endTimer()
                     defer span.End()
                     """, SMITHY_TRACING.func("StartSpan")));
 
@@ -358,6 +360,7 @@ private void generateOperationSerializerMiddleware(GenerationContext context, Op
             writer.write("in.Request = request");
             writer.write("");
 
+            writer.write("endTimer()");
             writer.write("span.End()");
             writer.write("return next.$L(ctx, in)", generator.getHandleMethodName());
         });
@@ -395,6 +398,7 @@ private void generateOperationDeserializerMiddleware(GenerationContext context,
 
             writer.write(goTemplate("""
                     _, span := $T(ctx, "OperationDeserializer")
+                    defer startMetricTimer(ctx, "client.call.deserialization_duration")()
                     defer span.End()
                     """, SMITHY_TRACING.func("StartSpan")));
 

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/integration/HttpRpcProtocolGenerator.java

@@ -149,6 +149,8 @@ private void generateOperationSerializer(GenerationContext context, OperationSha
 
             writer.write(goTemplate("""
                     _, span := $T(ctx, "OperationSerializer")
+                    endTimer := startMetricTimer(ctx, "client.call.serialization_duration")
+                    defer endTimer()
                     defer span.End()
                     """, SMITHY_TRACING.func("StartSpan")));
 
@@ -220,6 +222,7 @@ private void generateOperationSerializer(GenerationContext context, OperationSha
             writer.write("in.Request = request");
 
             writer.write("");
+            writer.write("endTimer()");
             writer.write("span.End()");
             writer.write("return next.$L(ctx, in)", generator.getHandleMethodName());
         });
@@ -341,6 +344,7 @@ private void generateOperationDeserializer(GenerationContext context, OperationS
 
             writer.write(goTemplate("""
                     _, span := $T(ctx, "OperationDeserializer")
+                    defer startMetricTimer(ctx, "client.call.deserialization_duration")()
                     defer span.End()
                     """, SMITHY_TRACING.func("StartSpan")));
 
@@ -378,7 +382,6 @@ private void generateOperationDeserializer(GenerationContext context, OperationS
             }
             writer.write("");
 
-            writer.write("span.End()");
             writer.write("return out, metadata, err");
         });
         writer.write("");

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/integration/ObservabilityOptions.java

@@ -32,25 +32,32 @@ public class ObservabilityOptions implements GoIntegration {
             .documentation("The client tracer provider.")
             .build();
 
+    private static final ConfigField METER_PROVIDER = ConfigField.builder()
+            .name("MeterProvider")
+            .type(SmithyGoDependency.SMITHY_METRICS.interfaceSymbol("MeterProvider"))
+            .documentation("The client meter provider.")
+            .build();
+
     private static final ConfigFieldResolver RESOLVE_TRACER_PROVIDER = ConfigFieldResolver.builder()
             .resolver(buildPackageSymbol("resolveTracerProvider"))
             .location(ConfigFieldResolver.Location.CLIENT)
             .target(ConfigFieldResolver.Target.INITIALIZATION)
             .build();
 
-    // TODO
-    //  private static final ConfigField METER_PROVIDER = ConfigField.builder()
-    //          .name("MeterProvider")
-    //          .type(SmithyGoDependency.SMITHY_METRICS.interfaceSymbol("MeterProvider"))
-    //          .documentation("The client meter provider.")
-    //          .build();
+    private static final ConfigFieldResolver RESOLVE_METER_PROVIDER = ConfigFieldResolver.builder()
+            .resolver(buildPackageSymbol("resolveMeterProvider"))
+            .location(ConfigFieldResolver.Location.CLIENT)
+            .target(ConfigFieldResolver.Target.INITIALIZATION)
+            .build();
 
     @Override
     public List<RuntimeClientPlugin> getClientPlugins() {
         return List.of(
                 RuntimeClientPlugin.builder()
                         .addConfigField(TRACER_PROVIDER)
+                        .addConfigField(METER_PROVIDER)
                         .addConfigFieldResolver(RESOLVE_TRACER_PROVIDER)
+                        .addConfigFieldResolver(RESOLVE_METER_PROVIDER)
                         .build()
         );
     }
@@ -63,6 +70,15 @@ func resolveTracerProvider(options *Options) {
                         options.TracerProvider = &$T{}
                     }
                 }
-                """, SmithyGoDependency.SMITHY_TRACING.struct("NopTracerProvider")));
+
+                func resolveMeterProvider(options *Options) {
+                    if options.MeterProvider == nil {
+                        options.MeterProvider = $T{}
+                    }
+                }
+                """,
+                SmithyGoDependency.SMITHY_TRACING.struct("NopTracerProvider"),
+                SmithyGoDependency.SMITHY_METRICS.struct("NopMeterProvider")
+        ));
     }
 }