7e5abd504f
Add three DBOS SDK skills with reference documentation for building reliable, fault-tolerant applications with durable workflows. Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
64 lines
1.9 KiB
Markdown
64 lines
1.9 KiB
Markdown
---
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title: Use Workflow IDs for Idempotency
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impact: MEDIUM
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impactDescription: Prevents duplicate side effects like double payments
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tags: pattern, idempotency, workflow-id, deduplication
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---
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## Use Workflow IDs for Idempotency
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Assign a workflow ID to ensure a workflow executes only once, even if called multiple times. This prevents duplicate side effects like double payments.
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**Incorrect (no idempotency):**
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```go
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func processPayment(ctx dbos.DBOSContext, orderID string) (string, error) {
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_, err := dbos.RunAsStep(ctx, func(ctx context.Context) (string, error) {
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return chargeCard(orderID)
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}, dbos.WithStepName("chargeCard"))
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return "charged", err
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}
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// Multiple calls could charge the card multiple times!
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dbos.RunWorkflow(ctx, processPayment, "order-123")
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dbos.RunWorkflow(ctx, processPayment, "order-123") // Double charge!
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```
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**Correct (with workflow ID):**
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```go
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func processPayment(ctx dbos.DBOSContext, orderID string) (string, error) {
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_, err := dbos.RunAsStep(ctx, func(ctx context.Context) (string, error) {
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return chargeCard(orderID)
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}, dbos.WithStepName("chargeCard"))
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return "charged", err
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}
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// Same workflow ID = only one execution
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workflowID := fmt.Sprintf("payment-%s", orderID)
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dbos.RunWorkflow(ctx, processPayment, "order-123",
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dbos.WithWorkflowID(workflowID),
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)
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dbos.RunWorkflow(ctx, processPayment, "order-123",
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dbos.WithWorkflowID(workflowID),
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)
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// Second call returns the result of the first execution
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```
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Access the current workflow ID inside a workflow:
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```go
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func myWorkflow(ctx dbos.DBOSContext, input string) (string, error) {
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currentID, err := dbos.GetWorkflowID(ctx)
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if err != nil {
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return "", err
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}
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fmt.Printf("Running workflow: %s\n", currentID)
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return input, nil
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}
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```
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Workflow IDs must be **globally unique** for your application. If not set, a random UUID is generated.
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Reference: [Workflow IDs and Idempotency](https://docs.dbos.dev/golang/tutorials/workflow-tutorial#workflow-ids-and-idempotency)
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