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Branch_Python

Node​

Node Description​

Branches to different downstream tasks based on results of Python function.

Retrieves table(s) from Ganymede data lake, processes via user-defined Python function, and stores result table(s) to Ganymede data lake.

Node Attributes​

  • output_table_results

Notes​

In the execute function, returning NodeReturn(tables_to_upload={'results': df}) would render the DataFrame df in the Flow Editor if Table Head visualization is enabled.

User-Defined Python​

Process tabular data from user-defined SQL query, writing results back to data lake. Data is written to the output bucket.

Parameters​

  • df_sql_result : pd.DataFrame | list[pd.DataFrame]
    • Table(s) or list of tables retrieved from user-defined SQL query
  • ganymede_context : GanymedeContext
    • Ganymede context variable, which stores flow run metadata

Returns​

BranchableNodeReturn A NodeReturn object with an additional parameter for specifying downstream nodes to execute, in addition to which tables and files to store in data lake / file storage. Some parameters are:

  • tables_to_upload: dict[str, pd.DataFrame] keys are table names, values are pandas DataFrames to upload
  • files_to_upload: dict[str, bytes] keys are file names, values are file data to upload
  • downstream_nodes_to_execute: bool | str | list[str] Boolean or string indicating whether to continue to next node in flow. If False, the flow will stop at this node. If True, the flow will continue to the next node(s). If a string or list of strings is provided, the flow will continue to the node(s) specified in the string(s).

Notes​

Files can also be retrieved and processed using the list_files and retrieve_files functions. Documentation on these functions can be found at https://docs.ganymede.bio/sdk/GanymedeClass