Connectors

A connector is a Python function, generated automatically, that maps one tool’s output onto the next tool’s input. One connector is generated per edge, so you never write the conversion between two tools by hand.

How connectors are created

The first time an edge executes, biocomposer generates its connector from the two tools’ declared schemas and the data actually produced at run time, so the mapping reflects what really exists and not just the declared types. The generated function is ordinary Python, cached for reuse, and can be read like any other code.

Connectors handle the practical differences between tools: matching fields that hold the same kind of data, converting formats, and selecting the right item when one tool produces many files and the next expects one.

Input nodes bypass connectors

Connectors are not generated for values you provide through an input node. Those are applied exactly as given, which is why input-node values take priority over upstream outputs on a key clash (Input merging and key clashes).