0.3.24

langgraph 0.3.24

Summary of Changes

• Added checkpoint migration mechanism to ensure backward compatibility with older checkpoint formats (#4125)
• Updated checkpoint version from 2 to 3 with consistent naming convention for channel keys (#4125)

Detailed Changes

langgraph.graph.state.StateGraph

• Added _migrate_checkpoint method to handle migrating between different checkpoint formats (#4125)
• Implemented migration logic to convert older channel key formats (start:node, branch:source:condition:node, or just node) to the new unified format branch:to:node (#4125)

langgraph.pregel.Pregel

• Added _migrate_checkpoint method to support checkpoint migration (#4125)
• Added checkpoint migration calls throughout the execution flow to ensure checkpoints are properly upgraded when loaded (#4125)
• Passed migration function to loop constructors to enable checkpoint migration at key points in execution (#4125)