feat: Simplify worker boilerplate with common helper

Add new_samples/common/cadence.go with NewCadenceClient() helper that
handles all gRPC/YARPC setup in one function call.

Before: worker.go was ~100 lines with manual YARPC dispatcher setup
After: worker.go is ~40 lines focused on workflow/activity registration

Key changes:
- common.NewCadenceClient() encapsulates all gRPC connection boilerplate
- Removed explicit logger/scope setup (Cadence provides defaults)
- Template updated to use the common helper

This is a stepping stone toward moving NewGrpcClient() to cadence-client
itself (per Nathanael's proposal in Slack).

Signed-off-by: Diana Zawadzki <[email protected]>

Author: zawadzkidiana

new_samples/common/cadence.go

@@ -0,0 +1,79 @@
+// Package common provides shared utilities for Cadence samples.
+// This simplifies worker setup by providing a one-liner for client creation.
+//
+// Once cadence-client adds NewGrpcClient(), this package can be replaced
+// with a direct import from go.uber.org/cadence/client.
+package common
+
+import (
+	"fmt"
+
+	apiv1 "github.com/uber/cadence-idl/go/proto/api/v1"
+	"go.uber.org/cadence/.gen/go/cadence/workflowserviceclient"
+	"go.uber.org/cadence/compatibility"
+	"go.uber.org/yarpc"
+	"go.uber.org/yarpc/peer"
+	"go.uber.org/yarpc/peer/hostport"
+	"go.uber.org/yarpc/transport/grpc"
+)
+
+const (
+	// DefaultHostPort is the default Cadence frontend address
+	DefaultHostPort = "127.0.0.1:7833"
+	// DefaultDomain is the default domain for samples
+	DefaultDomain = "cadence-samples"
+	// DefaultTaskList is the default task list for samples
+	DefaultTaskList = "cadence-samples-worker"
+	// CadenceService is the service name for YARPC
+	CadenceService = "cadence-frontend"
+)
+
+// NewCadenceClient creates a new Cadence client connected via gRPC.
+// This is a simplified helper that handles all the YARPC/gRPC boilerplate.
+//
+// Parameters:
+//   - caller: The name of the calling service (used for tracing)
+//   - hostPort: The Cadence frontend address (e.g., "localhost:7833")
+//   - dialOptions: Optional gRPC dial options (e.g., for TLS)
+//
+// Example:
+//
+//	client, err := common.NewCadenceClient("my-worker", "localhost:7833")
+func NewCadenceClient(caller, hostPort string, dialOptions ...grpc.DialOption) (workflowserviceclient.Interface, error) {
+	grpcTransport := grpc.NewTransport()
+
+	myChooser := peer.NewSingle(
+		hostport.Identify(hostPort),
+		grpcTransport.NewDialer(dialOptions...),
+	)
+	outbound := grpcTransport.NewOutbound(myChooser)
+
+	dispatcher := yarpc.NewDispatcher(yarpc.Config{
+		Name: caller,
+		Outbounds: yarpc.Outbounds{
+			CadenceService: {Unary: outbound},
+		},
+	})
+	if err := dispatcher.Start(); err != nil {
+		return nil, fmt.Errorf("failed to start dispatcher: %w", err)
+	}
+
+	clientConfig := dispatcher.ClientConfig(CadenceService)
+
+	return compatibility.NewThrift2ProtoAdapter(
+		apiv1.NewDomainAPIYARPCClient(clientConfig),
+		apiv1.NewWorkflowAPIYARPCClient(clientConfig),
+		apiv1.NewWorkerAPIYARPCClient(clientConfig),
+		apiv1.NewVisibilityAPIYARPCClient(clientConfig),
+	), nil
+}
+
+// MustNewCadenceClient is like NewCadenceClient but panics on error.
+// Useful for sample code where error handling would add noise.
+func MustNewCadenceClient(caller, hostPort string, dialOptions ...grpc.DialOption) workflowserviceclient.Interface {
+	client, err := NewCadenceClient(caller, hostPort, dialOptions...)
+	if err != nil {
+		panic(err)
+	}
+	return client
+}

new_samples/hello_world/README.md

@@ -43,14 +43,6 @@ cadence --env development \
   --input '{"message":"Cadence"}'
 ```
 
-You should see output like this:
-
-![Trigger command output](images/02-trigger-command-started-workflow.png)
-
-And the worker will log the completed workflow:
-
-![Worker output showing workflow completed](images/01-worker-output-workflow-completed.png)
-
 Here are the details to this command:
 
 * `--domain` option describes under which domain to run this workflow
@@ -68,17 +60,8 @@ To see more options run `cadence --help`
 
 Click on `cadence-samples` domain in cadence-web to view your workflow.
 
-![Workflow list showing completed workflow](images/03-web-ui-workflow-list-completed.png)
-
-Click on the workflow to see details:
-
 * In Summary tab, you will see the input and output to your workflow
-
-![Summary tab](images/04-web-ui-summary-tab.png)
-
-* Click on History tab to see individual steps. Expand an activity to see its result:
-
-![History tab with activity result](images/05-web-ui-history-activity-result.png)
+* Click on History tab to see individual steps.
 
 #### CLI
 
@@ -111,14 +94,6 @@ cadence --env development \
   --wid <workflow_id>
 ```
 
-## Troubleshooting
-
-If you see port conflicts when starting Docker, use `lsof` to find what's using the port:
-
-![Docker port conflict troubleshooting](images/06-docker-port-conflict-troubleshooting.png)
-
-See the main [README](../../README.md#docker-troubleshooting) for detailed Docker troubleshooting steps.
-
 ## References
 
 * The website: https://cadenceworkflow.io

new_samples/hello_world/worker.go

@@ -1,101 +1,41 @@
 // THIS IS A GENERATED FILE
 // PLEASE DO NOT EDIT
 
-// Package worker implements a Cadence worker with basic configurations.
 package main
 
 import (
-	"github.com/uber-go/tally"
-	apiv1 "github.com/uber/cadence-idl/go/proto/api/v1"
-	"go.uber.org/cadence/.gen/go/cadence/workflowserviceclient"
+	"github.com/uber-common/cadence-samples/new_samples/common"
 	"go.uber.org/cadence/activity"
-	"go.uber.org/cadence/compatibility"
 	"go.uber.org/cadence/worker"
 	"go.uber.org/cadence/workflow"
-	"go.uber.org/yarpc"
-	"go.uber.org/yarpc/peer"
-	yarpchostport "go.uber.org/yarpc/peer/hostport"
-	"go.uber.org/yarpc/transport/grpc"
 	"go.uber.org/zap"
-	"go.uber.org/zap/zapcore"
 )
 
-const (
-	HostPort = "127.0.0.1:7833"
-	Domain   = "cadence-samples"
-	// TaskListName identifies set of client workflows, activities, and workers.
-	// It could be your group or client or application name.
-	TaskListName   = "cadence-samples-worker"
-	ClientName     = "cadence-samples-worker"
-	CadenceService = "cadence-frontend"
-)
-
-// StartWorker creates and starts a basic Cadence worker.
+// StartWorker creates and starts a Cadence worker.
 func StartWorker() {
-	logger, cadenceClient := BuildLogger(), BuildCadenceClient()
-	workerOptions := worker.Options{
-		Logger:       logger,
-		MetricsScope: tally.NewTestScope(TaskListName, nil),
-	}
+	// Create Cadence client - all gRPC/YARPC boilerplate is handled by the helper
+	cadenceClient := common.MustNewCadenceClient(
+		common.DefaultTaskList,
+		common.DefaultHostPort,
+	)
 
 	w := worker.New(
 		cadenceClient,
-		Domain,
-		TaskListName,
-		workerOptions)
-	// HelloWorld workflow registration
-	w.RegisterWorkflowWithOptions(HelloWorldWorkflow, workflow.RegisterOptions{Name: "cadence_samples.HelloWorldWorkflow"})
-	w.RegisterActivityWithOptions(HelloWorldActivity, activity.RegisterOptions{Name: "cadence_samples.HelloWorldActivity"})
-
-	err := w.Start()
-	if err != nil {
-		panic("Failed to start worker: " + err.Error())
-	}
-	logger.Info("Started Worker.", zap.String("worker", TaskListName))
-
-}
-
-func BuildCadenceClient(dialOptions ...grpc.DialOption) workflowserviceclient.Interface {
-	grpcTransport := grpc.NewTransport()
-	// Create a single peer chooser that identifies the host/port and configures
-	// a gRPC dialer with TLS credentials
-	myChooser := peer.NewSingle(
-		yarpchostport.Identify(HostPort),
-		grpcTransport.NewDialer(dialOptions...),
+		common.DefaultDomain,
+		common.DefaultTaskList,
+		worker.Options{},
 	)
-	outbound := grpcTransport.NewOutbound(myChooser)
-
-	dispatcher := yarpc.NewDispatcher(yarpc.Config{
-		Name: ClientName,
-		Outbounds: yarpc.Outbounds{
-			CadenceService: {Unary: outbound},
-		},
-	})
-	if err := dispatcher.Start(); err != nil {
-		panic("Failed to start dispatcher: " + err.Error())
-	}
-
-	clientConfig := dispatcher.ClientConfig(CadenceService)
 
-	// Create a compatibility adapter that wraps proto-based YARPC clients
-	// to provide a unified interface for domain, workflow, worker, and visibility APIs
-	return compatibility.NewThrift2ProtoAdapter(
-		apiv1.NewDomainAPIYARPCClient(clientConfig),
-		apiv1.NewWorkflowAPIYARPCClient(clientConfig),
-		apiv1.NewWorkerAPIYARPCClient(clientConfig),
-		apiv1.NewVisibilityAPIYARPCClient(clientConfig),
-	)
-}
+	// Register workflows
+	w.RegisterWorkflowWithOptions(HelloWorldWorkflow, workflow.RegisterOptions{Name: "cadence_samples.HelloWorldWorkflow"})
 
-func BuildLogger() *zap.Logger {
-	config := zap.NewDevelopmentConfig()
-	config.Level.SetLevel(zapcore.InfoLevel)
+	// Register activities
+	w.RegisterActivityWithOptions(HelloWorldActivity, activity.RegisterOptions{Name: "cadence_samples.HelloWorldActivity"})
 
-	var err error
-	logger, err := config.Build()
-	if err != nil {
-		panic("Failed to setup logger: " + err.Error())
+	if err := w.Start(); err != nil {
+		panic("Failed to start worker: " + err.Error())
 	}
 
-	return logger
+	logger, _ := zap.NewDevelopment()
+	logger.Info("Started Worker.", zap.String("taskList", common.DefaultTaskList))
 }

new_samples/signal/worker.go

@@ -1,101 +1,41 @@
 // THIS IS A GENERATED FILE
 // PLEASE DO NOT EDIT
 
-// Package worker implements a Cadence worker with basic configurations.
 package main
 
 import (
-	"github.com/uber-go/tally"
-	apiv1 "github.com/uber/cadence-idl/go/proto/api/v1"
-	"go.uber.org/cadence/.gen/go/cadence/workflowserviceclient"
+	"github.com/uber-common/cadence-samples/new_samples/common"
 	"go.uber.org/cadence/activity"
-	"go.uber.org/cadence/compatibility"
 	"go.uber.org/cadence/worker"
 	"go.uber.org/cadence/workflow"
-	"go.uber.org/yarpc"
-	"go.uber.org/yarpc/peer"
-	yarpchostport "go.uber.org/yarpc/peer/hostport"
-	"go.uber.org/yarpc/transport/grpc"
 	"go.uber.org/zap"
-	"go.uber.org/zap/zapcore"
 )
 
-const (
-	HostPort = "127.0.0.1:7833"
-	Domain   = "cadence-samples"
-	// TaskListName identifies set of client workflows, activities, and workers.
-	// It could be your group or client or application name.
-	TaskListName   = "cadence-samples-worker"
-	ClientName     = "cadence-samples-worker"
-	CadenceService = "cadence-frontend"
-)
-
-// StartWorker creates and starts a basic Cadence worker.
+// StartWorker creates and starts a Cadence worker.
 func StartWorker() {
-	logger, cadenceClient := BuildLogger(), BuildCadenceClient()
-	workerOptions := worker.Options{
-		Logger:       logger,
-		MetricsScope: tally.NewTestScope(TaskListName, nil),
-	}
+	// Create Cadence client - all gRPC/YARPC boilerplate is handled by the helper
+	cadenceClient := common.MustNewCadenceClient(
+		common.DefaultTaskList,
+		common.DefaultHostPort,
+	)
 
 	w := worker.New(
 		cadenceClient,
-		Domain,
-		TaskListName,
-		workerOptions)
-	// HelloWorld workflow registration
-	w.RegisterWorkflowWithOptions(SimpleSignalWorkflow, workflow.RegisterOptions{Name: "cadence_samples.SimpleSignalWorkflow"})
-	w.RegisterActivityWithOptions(SimpleSignalActivity, activity.RegisterOptions{Name: "cadence_samples.SimpleSignalActivity"})
-
-	err := w.Start()
-	if err != nil {
-		panic("Failed to start worker: " + err.Error())
-	}
-	logger.Info("Started Worker.", zap.String("worker", TaskListName))
-
-}
-
-func BuildCadenceClient(dialOptions ...grpc.DialOption) workflowserviceclient.Interface {
-	grpcTransport := grpc.NewTransport()
-	// Create a single peer chooser that identifies the host/port and configures
-	// a gRPC dialer with TLS credentials
-	myChooser := peer.NewSingle(
-		yarpchostport.Identify(HostPort),
-		grpcTransport.NewDialer(dialOptions...),
+		common.DefaultDomain,
+		common.DefaultTaskList,
+		worker.Options{},
 	)
-	outbound := grpcTransport.NewOutbound(myChooser)
-
-	dispatcher := yarpc.NewDispatcher(yarpc.Config{
-		Name: ClientName,
-		Outbounds: yarpc.Outbounds{
-			CadenceService: {Unary: outbound},
-		},
-	})
-	if err := dispatcher.Start(); err != nil {
-		panic("Failed to start dispatcher: " + err.Error())
-	}
-
-	clientConfig := dispatcher.ClientConfig(CadenceService)
 
-	// Create a compatibility adapter that wraps proto-based YARPC clients
-	// to provide a unified interface for domain, workflow, worker, and visibility APIs
-	return compatibility.NewThrift2ProtoAdapter(
-		apiv1.NewDomainAPIYARPCClient(clientConfig),
-		apiv1.NewWorkflowAPIYARPCClient(clientConfig),
-		apiv1.NewWorkerAPIYARPCClient(clientConfig),
-		apiv1.NewVisibilityAPIYARPCClient(clientConfig),
-	)
-}
+	// Register workflows
+	w.RegisterWorkflowWithOptions(SimpleSignalWorkflow, workflow.RegisterOptions{Name: "cadence_samples.SimpleSignalWorkflow"})
 
-func BuildLogger() *zap.Logger {
-	config := zap.NewDevelopmentConfig()
-	config.Level.SetLevel(zapcore.InfoLevel)
+	// Register activities
+	w.RegisterActivityWithOptions(SimpleSignalActivity, activity.RegisterOptions{Name: "cadence_samples.SimpleSignalActivity"})
 
-	var err error
-	logger, err := config.Build()
-	if err != nil {
-		panic("Failed to setup logger: " + err.Error())
+	if err := w.Start(); err != nil {
+		panic("Failed to start worker: " + err.Error())
 	}
 
-	return logger
+	logger, _ := zap.NewDevelopment()
+	logger.Info("Started Worker.", zap.String("taskList", common.DefaultTaskList))
 }