Project Merge Algorithm

Algorithm to merge one workflow (the source) into another (the target)

Eg, when merging staging into main, staging is the source and main is the target

The exercise here is basically to map the source nodes to UUIDS in the target workflow

MERGE(sourceWorkflow, targetWorkflow):

Note: in the CLI, merge returns a new workflow and does not mutate source or target.

• Build an index of of all the nodes in the target workflow, by id (in CLI this means name, not UUID)
• Build a POOL of nodes in the workflow. No sorting required.
• Call MATCH_SOLID to map trivial nodes into an ID Map
• For each node in the POOL:
  • Call MATCH_EXPRESSION to map nodes with the same expression
  • Call MATCH_PARENT to map nodes with the same structural position in the workflow
  • Call MATCH_POSITION to map nodes with the same layout location
• At the end of the loop, If a) there are still nodes left, AND b) new ids were added to the ID MAP in the last iteration, run the loop again
• After the pool is exhausted, or all ids have been mapped, any nodes still in the pool need a new UUID
• Call MAP_EDGES with the latest version of the target workflow

MATCH_SOLID(sourceNodes, targetNodes)

• For each node in the source pool
• Look for a single node in the target pool with the same name (in CLI, use id instead of name)
• If there's a match, call REPLACE_NODE
• If there are two source nodes with the same id... error? Or continue?

MATCH_EXPRESSION(sourceNodes, targetNodes)

• For each Step type node in the source pool
• Look for a single node in the target pool with the same expression
• (later) Attempt a fuzzy match, rather than an exact one
• If there's a single match, call REPLACE_NODE
• If there are multiple matches, call MATCH_PARENT and MATCH_ADAPTOR to find a match

MATCH_PARENT(sourceNodes, targetNodes)

• For each Step type node in the source pool
• Look for a single node in the target pool with the same parent
• If there are multiple matches, call MATCH_ADAPTOR to find a match

MATCH_ADAPTOR(sourceNodes, targetNodes)

• For each Step type node in the source pool
• Look for a single node in the target pool with the same adaptor
• If there's a single match, call REPLACE_NODE

MAP_EDGES(sourceWorkflow, targetWorkflow):

• for each edge in the source
• identify the new from/to UUIDS for the edge
• In the target, find an edge with the same from/to UUIDS
• Replace the target edge properties with the source edge propertes (excluding any properties?)

MATCH_EDGES()

• for each edge in the target
• Get the UUIDs of the source and target
• Find the corrsponsing
• Call REPLACE_NODE

REPLACE_NODE(source, target):

Replace the values of the target node with the values of the source (or, apply the properties of the source to the target)

• clone the source node into a new node
• apply the UUID from the target node into the new node
• (copy other properties from the target, maybe some options? Maybe the credential?)
• Remove the source and target node form both pools