Merge pull request #59 from JoshVanL/error-type-for-missing-task-result-0.10

[1.10] Task Result: Type error for missing task result

Author: cicoyle

api/errors.go

@@ -0,0 +1,58 @@
+package api
+
+import (
+	"errors"
+	"fmt"
+)
+
+var (
+	ErrInstanceNotFound  = errors.New("no such instance exists")
+	ErrNotStarted        = errors.New("orchestration has not started")
+	ErrNotCompleted      = errors.New("orchestration has not yet completed")
+	ErrNoFailures        = errors.New("orchestration did not report failure details")
+	ErrDuplicateInstance = errors.New("orchestration instance already exists")
+	ErrIgnoreInstance    = errors.New("ignore creating orchestration instance")
+	ErrTaskCancelled     = errors.New("task was cancelled")
+
+	EmptyInstanceID = InstanceID("")
+)
+
+type UnknownTaskIDError struct {
+	TaskID     int32
+	InstanceID string
+}
+
+func NewUnknownTaskIDError(instanceID string, taskID int32) error {
+	return &UnknownTaskIDError{
+		TaskID:     taskID,
+		InstanceID: instanceID,
+	}
+}
+
+func (e *UnknownTaskIDError) Error() string {
+	return fmt.Sprintf("unknown instance ID/task ID combo: %s/%d", e.InstanceID, e.TaskID)
+}
+
+func IsUnknownTaskIDError(err error) bool {
+	_, ok := err.(*UnknownTaskIDError)
+	return ok
+}
+
+type UnknownInstanceIDError struct {
+	InstanceID string
+}
+
+func NewUnknownInstanceIDError(instanceID string) error {
+	return &UnknownInstanceIDError{
+		InstanceID: instanceID,
+	}
+}
+
+func (e *UnknownInstanceIDError) Error() string {
+	return fmt.Sprintf("unknown instance ID: %s", e.InstanceID)
+}
+
+func IsUnknownInstanceIDError(err error) bool {
+	_, ok := err.(*UnknownInstanceIDError)
+	return ok
+}

api/orchestration.go

@@ -2,7 +2,6 @@ package api
 
 import (
 	"encoding/json"
-	"errors"
 	"time"
 
 	"github.com/dapr/durabletask-go/api/protos"
@@ -11,18 +10,6 @@ import (
 	"google.golang.org/protobuf/types/known/wrapperspb"
 )
 
-var (
-	ErrInstanceNotFound  = errors.New("no such instance exists")
-	ErrNotStarted        = errors.New("orchestration has not started")
-	ErrNotCompleted      = errors.New("orchestration has not yet completed")
-	ErrNoFailures        = errors.New("orchestration did not report failure details")
-	ErrDuplicateInstance = errors.New("orchestration instance already exists")
-	ErrIgnoreInstance    = errors.New("ignore creating orchestration instance")
-	ErrTaskCancelled     = errors.New("task was cancelled")
-
-	EmptyInstanceID = InstanceID("")
-)
-
 type CreateOrchestrationAction = protos.CreateOrchestrationAction
 
 const (

backend/local/task.go

@@ -2,8 +2,6 @@ package local
 
 import (
 	"context"
-	"fmt"
-	"strconv"
 	"sync"
 
 	"github.com/dapr/durabletask-go/api"
@@ -37,14 +35,15 @@ func (be *TasksBackend) CompleteActivityTask(ctx context.Context, response *prot
 	if be.deletePendingActivityTask(response.GetInstanceId(), response.GetTaskId(), response) {
 		return nil
 	}
-	return fmt.Errorf("unknown instance ID/task ID combo: %s", response.GetInstanceId()+"/"+strconv.FormatInt(int64(response.GetTaskId()), 10))
+
+	return api.NewUnknownTaskIDError(response.GetInstanceId(), response.GetTaskId())
 }
 
 func (be *TasksBackend) CancelActivityTask(ctx context.Context, instanceID api.InstanceID, taskID int32) error {
 	if be.deletePendingActivityTask(string(instanceID), taskID, nil) {
 		return nil
 	}
-	return fmt.Errorf("unknown instance ID/task ID combo: %s", string(instanceID)+"/"+strconv.FormatInt(int64(taskID), 10))
+	return api.NewUnknownTaskIDError(instanceID.String(), taskID)
 }
 
 func (be *TasksBackend) WaitForActivityCompletion(ctx context.Context, request *protos.ActivityRequest) (*protos.ActivityResponse, error) {
@@ -70,14 +69,14 @@ func (be *TasksBackend) CompleteOrchestratorTask(ctx context.Context, response *
 	if be.deletePendingOrchestrator(response.GetInstanceId(), response) {
 		return nil
 	}
-	return fmt.Errorf("unknown instance ID: %s", response.GetInstanceId())
+	return api.NewUnknownInstanceIDError(response.GetInstanceId())
 }
 
 func (be *TasksBackend) CancelOrchestratorTask(ctx context.Context, instanceID api.InstanceID) error {
 	if be.deletePendingOrchestrator(string(instanceID), nil) {
 		return nil
 	}
-	return fmt.Errorf("unknown instance ID: %s", instanceID)
+	return api.NewUnknownInstanceIDError(instanceID.String())
 }
 
 func (be *TasksBackend) WaitForOrchestratorCompletion(ctx context.Context, request *protos.OrchestratorRequest) (*protos.OrchestratorResponse, error) {