Expose the deployment identifier to the application. (#726)

This was a feature requested by one of our users so that they
can distinct between multiple deployments of the same application.

Author: spetrovic77

.github/workflows/go.yml

@@ -81,11 +81,11 @@ jobs:
         uses: actions/cache@v3
         with:
           path: ~/go/bin/staticcheck
-          key: staticcheck-v0.4.3
+          key: staticcheck-v0.4.6
         if: ${{ matrix.command == 'lint' }}
 
       - name: Install linter
-        run: go install honnef.co/go/tools/cmd/[email protected].3
+        run: go install honnef.co/go/tools/cmd/[email protected].6
         if: ${{ matrix.command == 'lint' }}
 
       - name: Build the weaver binary

dev/build_and_test

@@ -54,7 +54,7 @@ function cmd_vet() {
 
 function cmd_lint() {
   if ! exists staticcheck; then
-    printf "staticcheck not found; install via\ngo install honnef.co/go/tools/cmd/[email protected].3\n" >&2
+    printf "staticcheck not found; install via\ngo install honnef.co/go/tools/cmd/[email protected].6\n" >&2
     exit 1
   fi
 

fill.go

@@ -27,6 +27,7 @@ import (
 func init() {
 	// See internal/weaver/types.go.
 	weaver.SetLogger = setLogger
+	weaver.SetWeaverInfo = setWeaverInfo
 	weaver.HasRefs = hasRefs
 	weaver.FillRefs = fillRefs
 	weaver.HasListeners = hasListeners
@@ -39,12 +40,22 @@ func init() {
 func setLogger(v any, logger *slog.Logger) error {
 	x, ok := v.(interface{ setLogger(*slog.Logger) })
 	if !ok {
-		return fmt.Errorf("FillLogger: %T does not implement weaver.Implements", v)
+		return fmt.Errorf("setLogger: %T does not implement weaver.Implements", v)
 	}
 	x.setLogger(logger)
 	return nil
 }
 
+// See internal/weaver/types.go.
+func setWeaverInfo(impl any, info *weaver.WeaverInfo) error {
+	x, ok := impl.(interface{ setWeaverInfo(*weaver.WeaverInfo) })
+	if !ok {
+		return fmt.Errorf("setWeaverInfo: %T does not implement weaver.Implements", impl)
+	}
+	x.setWeaverInfo(info)
+	return nil
+}
+
 // See internal/weaver/types.go.
 func hasRefs(impl any) bool {
 	p := reflect.ValueOf(impl)

godeps.txt

@@ -390,6 +390,7 @@ github.com/ServiceWeaver/weaver/internal/sim
     github.com/ServiceWeaver/weaver/runtime/codegen
     github.com/ServiceWeaver/weaver/runtime/logging
     github.com/ServiceWeaver/weaver/runtime/protos
+    github.com/google/uuid
     go.opentelemetry.io/otel/codes
     go.opentelemetry.io/otel/trace
     golang.org/x/exp/maps

internal/sim/executor.go

@@ -30,6 +30,7 @@ import (
 	"github.com/ServiceWeaver/weaver/runtime"
 	"github.com/ServiceWeaver/weaver/runtime/codegen"
 	"github.com/ServiceWeaver/weaver/runtime/protos"
+	"github.com/google/uuid"
 	"golang.org/x/sync/errgroup"
 )
 
@@ -286,6 +287,15 @@ func (e *executor) reset(workload Workload, fakes map[reflect.Type]any, ops []*o
 	e.nextTraceID = 1
 	e.nextSpanID = 1
 
+	// Pick a deterministic deployment ID.
+	depID, err := newUUID(e.rand)
+	if err != nil {
+		return err
+	}
+	weaverInfo := &weaver.WeaverInfo{
+		DeploymentID: depID.String(),
+	}
+
 	// Fill ref fields inside the workload struct.
 	if err := weaver.FillRefs(workload, func(t reflect.Type) (any, error) {
 		return e.getIntf(t, "op", 0)
@@ -326,6 +336,11 @@ func (e *executor) reset(workload Workload, fakes map[reflect.Type]any, ops []*o
 				return err
 			}
 
+			// Set application runtime information.
+			if err := weaver.SetWeaverInfo(obj, weaverInfo); err != nil {
+				return err
+			}
+
 			// Fill ref fields.
 			if e.info.hasRefs[reg.Iface] {
 				if err := weaver.FillRefs(obj, func(t reflect.Type) (any, error) {
@@ -741,3 +756,9 @@ func returnError(component reflect.Type, method string, err error) []reflect.Val
 	returns[n-1] = reflect.ValueOf(err)
 	return returns
 }
+
+func newUUID(r *rand.Rand) (uuid.UUID, error) {
+	var bytes [16]byte
+	r.Read(bytes[:])
+	return uuid.FromBytes(bytes[:])
+}

internal/testdeployer/components.go

@@ -40,6 +40,10 @@ type c interface {
 	C(context.Context, int) (int, error)
 }
 
+type d interface {
+	D(context.Context) (string, error)
+}
+
 type aimpl struct {
 	weaver.Implements[a]
 	lis weaver.Listener //lint:ignore U1000 used in remoteweavelet_test.go
@@ -55,6 +59,10 @@ type cimpl struct {
 	weaver.Implements[c]
 }
 
+type dimpl struct {
+	weaver.Implements[d]
+}
+
 func (a *aimpl) A(ctx context.Context, x int) (int, error) {
 	a.Logger(ctx).Debug("A")
 	return a.b.Get().B(ctx, x)
@@ -72,3 +80,7 @@ func (c *cimpl) C(ctx context.Context, x int) (int, error) {
 	c_calls.Inc()
 	return x, nil
 }
+
+func (d *dimpl) D(ctx context.Context) (string, error) {
+	return d.Weaver().DeploymentID, nil
+}

internal/testdeployer/remoteweavelet_test.go

@@ -48,6 +48,7 @@ var (
 	componenta = "github.com/ServiceWeaver/weaver/internal/testdeployer/a"
 	componentb = "github.com/ServiceWeaver/weaver/internal/testdeployer/b"
 	componentc = "github.com/ServiceWeaver/weaver/internal/testdeployer/c"
+	componentd = "github.com/ServiceWeaver/weaver/internal/testdeployer/d"
 	colocated  = map[string][]string{"1": {componenta, componentb, componentc}}
 )
 
@@ -125,9 +126,10 @@ func spawn(ctx context.Context, info *protos.WeaveletArgs, handler envelope.Enve
 // deployer is a simple testing deployer that spawns all weavelets in the
 // current process.
 type deployer struct {
-	t         *testing.T           // underlying unit test
-	ctx       context.Context      // context used to spawn weavelets
-	cancel    context.CancelFunc   // shuts down the deployer and all weavelets
+	t         *testing.T         // underlying unit test
+	ctx       context.Context    // context used to spawn weavelets
+	cancel    context.CancelFunc // shuts down the deployer and all weavelets
+	info      *protos.WeaveletArgs
 	logger    *logging.TestLogger  // logger
 	threads   *errgroup.Group      // background threads
 	placement map[string][]string  // weavelet -> components
@@ -194,6 +196,7 @@ func deployWithInfo(t *testing.T, ctx context.Context, placement map[string][]st
 	threads, ctx := errgroup.WithContext(ctx)
 	d := &deployer{
 		t:         t,
+		info:      protomsg.Clone(info),
 		ctx:       ctx,
 		cancel:    cancel,
 		logger:    logging.NewTestLogger(t, testing.Verbose()),
@@ -209,7 +212,7 @@ func deployWithInfo(t *testing.T, ctx context.Context, placement map[string][]st
 	// Spawn the weavelets.
 	tmpDir := t.TempDir()
 	for name := range placement {
-		info := protomsg.Clone(info)
+		info := d.info
 		info.Id = uuid.New().String()
 		weavelet, err := spawn(ctx, info, d, logger, tmpDir)
 		if err != nil {
@@ -324,20 +327,34 @@ func (d *deployer) VerifyServerCertificate(context.Context, *protos.VerifyServer
 }
 
 // testComponents tests that the components spawned by d are working properly.
-func testComponents(d *deployer) {
-	d.t.Helper()
-	const want = 42
-	for _, name := range d.placedAt[componenta] {
-		x, err := d.weavelets[name].wlet.GetIntf(reflection.Type[a]())
+func testComponents(dep *deployer) {
+	dep.t.Helper()
+	for _, name := range dep.placedAt[componenta] {
+		x, err := dep.weavelets[name].wlet.GetIntf(reflection.Type[a]())
 		if err != nil {
-			d.t.Fatal(err)
+			dep.t.Fatal(err)
 		}
-		got, err := x.(a).A(d.ctx, want)
+		const want = 42
+		got, err := x.(a).A(dep.ctx, want)
 		if err != nil {
-			d.t.Fatal(err)
+			dep.t.Fatal(err)
+		}
+		if got != want {
+			dep.t.Fatalf("A(%d): got %d, want %d", want, got, want)
+		}
+	}
+	for _, name := range dep.placedAt[componentd] {
+		x, err := dep.weavelets[name].wlet.GetIntf(reflection.Type[d]())
+		if err != nil {
+			dep.t.Fatal(err)
+		}
+		got, err := x.(d).D(dep.ctx)
+		if err != nil {
+			dep.t.Fatal(err)
 		}
+		want := dep.info.DeploymentId
 		if got != want {
-			d.t.Fatalf("A(%d): got %d, want %d", want, got, want)
+			dep.t.Fatalf("D(): got %s, want %s", got, want)
 		}
 	}
 }
@@ -799,7 +816,7 @@ func TestMetrics(t *testing.T) {
 			t.Fatal(err)
 		}
 		if got != want {
-			t.Fatalf("A(%d): got %d, want %d", want, got, want)
+			t.Fatalf("C(%d): got %d, want %d", want, got, want)
 		}
 	}