Package File (sdf-package.yaml)

Packages enable you to organize your code into logical units and reuse them across dataflows. A package may define functions, types, and states built and tested independently and imported in dataflows.

Package files do not have code, but rather API definitions that are used to generate code. The sdf CLI generate command uses the API definitions to generate the code. Afte running the code generator, use your favorite editor to build and test the package.

The package file is defined in YAML and has the following hierarchy:

# sdf-package.yaml
apiVersion: <version>

meta:
  name: <package-name>
  version: <package-version>
  namespace: <package-namespace>

imports:
  - pkg: <package-namespace>/<package-name>@<package-version>
    types:
      - name: <type-name>
    functions:
      - name: <function-name>
    states:
      - name: <state-name>

types:
  <type-name>: <type-props>

states:
  <state-name>: <state-props>

functions:
  <function-name>:
    operator: <operator-type>
    states: 
      - name: <state-name>
    inputs:
      - name: <input-name>
        type: <input-type>
    output:
      type: <output-type>

dev:
  converter: <converter-props>
  imports:
    - pkg:  <package-namespace>/<package-name>@<package-version>
      path: <relative-path>

The sections are as follows:

• apiVersion - defines engine version of the package file.
• meta - defines the name, version, and namespace of the package.
• imports - imports other packages’ types, states, functions (optional)
• types - definess the type definitions (optional).
• states - definess the state definitions (optional).
• functions - definess the function names, operators, states, the input and output parameters (optional).
• dev - defines the substitutions to be used during development and test (optional).

The sdf command line tool offers commands to build and test a package file.

Navigate to the directory with the sdf-package.yaml and perform the following commands:

1. Generate the build environment:

$ sdf generate

Add your code in the rust directory.

2. Build the package:

$ sdf build

3. Test the package

$ sdf test

After you’ve built and tested the packages, you can import the components in a dataflow file to create the data pipeline.

• Check out the examples in github on how to build and use packages in dataflows.