Wren

sutura reads a WrenAI MDL manifest with the sutura import wren command. The command writes a markdown catalog for a person to review and commit. The crate is sutura-catalog-wren. Wren is not a catalog kind: sutura serves the output as kind: markdown.

When to use it

• Use it for single-player governance. One owner reviews the converted files and commits them to the repository. The single player example shows this model with the markdown catalog.
• Your semantic model is in WrenAI.

Usage

sutura import wren <wren-project-dir> <out-dir>

• <wren-project-dir> contains manifest.json, an MDL manifest of layout version 2.
• <out-dir> must be empty. If it contains a file, the command writes nothing.

The command runs offline and uses no settings keys. It writes:

Path	Contents
models/*.md	One model document for each Wren model
relationships/*.md	One relationship document for each Wren relationship
metrics/*.md	One kind: cube document for each Wren cube
declaration.md	What the catalog supplies
report.txt	Every part of the manifest that the command could not convert

Serve the output

Every converted model has source: wren. Declare a data system with that alias, and point a markdown catalog at the output:

catalogs:
  - name: "model"
    kind: "markdown"
    dir: "/srv/sutura/wren-catalog"
    data_dir: "/srv/sutura/data"
    version: "wren-import-1"
sources:
  wren:
    kind: "files"
    data_dir: "/srv/sutura/data"
    posture: "shared-service-user"

sutura serve reads all catalog entries again at the shortest refresh_seconds among them. The default is 900, and 0 is refused. See Serving.

The refresh reads the converted directory, not the Wren manifest. A change to the manifest reaches sutura serve only after you run sutura import wren again.

What the command converts

The command converts a column, one aggregate over one column, a ratio of two such aggregates, and a join on equal columns. It refuses anything else by name in report.txt: for example SQL models, calculated columns, access-control rules and many-to-many relationships. Wren has no audience and no grain, so each converted metric gets audience: open and the grain day. Review both before you commit the catalog.