Creating a New Python App

If you haven't already, you'll first need to set up your development environment and ensure you have a Grainite server running (can be running locally in a Docker container).

1. Develop your Application

Create your Application Config File

Here you would configure your application in a YAML file. You may use App Configuration Options as a reference.

app.yaml template

app_name: food_app
# For python: Location of root python app directories relative to this config file.
python_dir: python_app

topics:
    - topic_name: orders_topic
      key_name: order_id
      key_type: string

tables:
    - table_name: orders_table
      key_type: string
      action_handlers:
          # Supported types: java, python
          - type: python
            script_path: handlers/orders_handler.py
            actions:
                - action_name: handleOrders
                  # `method_name` is optional. Default method_name is the `action_name`
                  method_name: handle_orders
                  # `handles_multiple_actions` is optional. Default is `false`.
                  handles_multiple_actions: false
                  subscriptions:
                      - subscription_name: orderUpdates
                        topic_name: orders_topic
                        topic_key: order_id

Implement the Application Logic

Implement your action handlers, client programs, and any other parts of your app's functionality. You may use the API pages here or the Grainite Pydocs for reference.

2. Load the Application

Load the application onto the Grainite server from the app's main directory.

gx load

pageApp Load (gx load)

4. Run the load

Run your client program to send events to the application.

python3 Client.py

5. Observe the Application

• Print all events in the topic: gx topic dump <topic name>

• Print all grains in the table: gx table dump <table name>

pageTopic Commands (gx topic)pageTable Commands (gx table)

Refer to the GX CLI document for more in-depth information about gx.

pagegx CLI