Flowman Schema Generator

The Flowman schema generator is a small utility application which generates a YAML schema file from the current configuration including all plugins. This YAML schema file then can be used to in appropriate code editors which support schema validation of YAML files. This will support developers in creating Flowman projects by enabling better syntax highlighting and code auto-completion.

flowman-schema -o my-schema-directory

This command will create multiple different YAML schema files:

  • module.json - This is the YAML schema for all modules, i.e. defining relations, mapping, etc.
  • project.json - This YAML schema file contains all entities of the project.yml file.
  • namespace.sjon - This YAML schema file contains all entities of namespace definitions.
  • documentation.sjon - This YAML schema file contains all entities of documentation.yml.

Provided Schemas

Since version 0.27.1, Flowman will contain pre-generated schema definitions ready to use. The schema will include entity definitions from all plugins.

But there may still be a good reason for you to generate a custom schema, which perfectly fits to your Flowman setup: Since the available entities and YAML tags depend on the presence of plugins, the best solution is to provide some means to generate a YAML schema file precisely for your configuration.

Supported Editors

JSON schema definition files are supported by many code editors. The following editors are known to work well with validation and auto-completion with the Flowman YAML schema files:

  • JetBrains IntelliJ (and probably other IDEs from the JetBrains family)
  • Microsoft Visual Studio Code (via the YAML plugin)

Please refer to the corresponding documentation how to configure each editor to use the YAML schema definitions.

Setup JetBrains IntelliJ

Adding the JSON schema in IntelliJ is simple to do.

  1. Open the settings dialog via File > Settings…
  2. Go to Language & Frameworks > Schemas & DTDs > JSON Schema Mappings
  3. Add a new entry, assign it a name (”Flowman Module Schema”), and assign the module.json schema file (Version 4)
  4. Add your Flowman project directories to the newly created JSON Schema

Repeat the steps for the project.json and namespace.yml, and assign them the individual files (project.yml and possibly default-namespace.yml).

Setup Visual Studio Code

In order to benefit from a really excellent autocompletion in Visual Studio Code, you need to install the YAML plugin. Then you can easily add

  1. Open your Visual Studio Code settings.json file
  2. Add appropriate mappings for the Flowman YAML schema files:
    "yaml.schemas": {
        "/home/kaya/Dimajix/flowman-schema/project.json": "flows/**/project.yml",
        "/home/kaya/Dimajix/flowman-schema/documentation.json": "flows/**/documentation.yml",
        "/home/kaya/Dimajix/flowman-schema/module.json": "flows/*/*/*.yml"