fix(streaming-api): fix streaming execution

[Sg312]

Summary

Fix streaming execution

Type of Change

• Bug fix

Testing

Manual

Checklist

• Code follows project style guidelines
• Self-reviewed my changes
• Tests added/updated and passing
• No new warnings introduced
• I confirm that I have read and agree to the terms outlined in the Contributor License Agreement (CLA)

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Project	Deployment	Preview	Comments	Updated (UTC)
docs	Ready	Preview	Comment	Nov 7, 2025 10:24pm

[greptile-apps]

Greptile Overview

Greptile Summary

This PR fixes the streaming API execution path by introducing proper output ID resolution and delegating to a centralized streaming implementation.

Key Changes

• Added resolveOutputIds function to convert human-readable block names (e.g. BlockName.path) to UUID-based IDs (e.g. uuid_path)
• Split SSE streaming into two paths:
  • Draft state mode: Uses existing manual SSE implementation for console log streaming
  • Deployed state mode: Uses new createStreamingResponse helper for filtered API responses
• Imported uuidValidate for proper UUID detection (replacing regex-based validation)

How it works

When executing deployed workflows with streaming enabled and selectedOutputs specified, the code now:

1. Loads the deployed workflow state to access block metadata
2. Resolves output IDs by matching block names to their UUIDs
3. Delegates to createStreamingResponse which handles streaming execution with proper output filtering and tokenization

This consolidates streaming logic and ensures consistent behavior across API and chat execution paths.

Confidence Score: 4/5

• This PR is safe to merge with minimal risk after thorough testing
• The changes consolidate streaming logic and add proper output ID resolution. The implementation is sound with defensive checks (undefined handling, logging warnings for invalid IDs). Score is 4 instead of 5 due to: (1) lack of tests in the PR, (2) the resolveOutputIds function has edge cases that should be verified with real-world data, and (3) this changes critical execution paths for deployed workflows
• Verify apps/sim/app/api/workflows/[id]/execute/route.ts with integration tests covering edge cases in output ID resolution (UUIDs with underscores, block names with special characters)

Important Files Changed

File Analysis

Filename	Score	Overview
apps/sim/app/api/workflows/[id]/execute/route.ts	4/5	Added streaming API response path with output ID resolution to convert block names to UUIDs; refactored SSE streaming to use createStreamingResponse for deployed workflows

Sequence Diagram

sequenceDiagram
participant Client
participant POST_Handler as POST /api/workflows/[id]/execute
participant resolveOutputIds
participant createStreamingResponse
participant executeWorkflow
participant executeWorkflowCore
Client->>POST_Handler: POST request with selectedOutputs
POST_Handler->>POST_Handler: Check auth & validate workflow
POST_Handler->>POST_Handler: Process input files
alt enableSSE = false
POST_Handler->>executeWorkflowCore: Execute with callbacks={}
executeWorkflowCore-->>POST_Handler: Return result
POST_Handler-->>Client: JSON response
else enableSSE = true && shouldUseDraftState
Note over POST_Handler: Manual SSE console log streaming path
POST_Handler->>POST_Handler: Create ReadableStream with callbacks
POST_Handler->>executeWorkflowCore: Execute with onBlockStart/onBlockComplete/onStream
executeWorkflowCore-->>POST_Handler: Stream events
POST_Handler-->>Client: SSE stream with execution events
else enableSSE = true && !shouldUseDraftState
Note over POST_Handler: NEW: Streaming API response path
POST_Handler->>POST_Handler: Load deployed workflow state
POST_Handler->>resolveOutputIds: Convert block names to UUIDs
resolveOutputIds-->>POST_Handler: Resolved output IDs
POST_Handler->>createStreamingResponse: Create streaming response
createStreamingResponse->>executeWorkflow: Execute with streaming callbacks
executeWorkflow->>executeWorkflowCore: Execute with callbacks
executeWorkflowCore-->>executeWorkflow: Return result with logs
executeWorkflow-->>createStreamingResponse: Process streaming outputs
createStreamingResponse-->>POST_Handler: ReadableStream
POST_Handler-->>Client: SSE stream with filtered outputs
end

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