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@app_startup

Macro to define a code block that should only be executed at the startup of the application (app dry-run). Usage:

@app_startup begin
    # app initialization logic
end

Internally, this macro is implemented by checking the result of is_app_first_pass() and running the @app_startup code block only if it returns true.

Usage​

You can define multiple @app_startup code blocks, but we recommend you to keep all of your app initialization logic inside a single @app_startup block near the top of your entry-point script (app.jl by default).

Although apps are not required to have @app_startup code blocks, some initialization tasks should be only performed inside @app_startup code blocks. See below what you are expected to do inside @app_startup code blocks.

1. Definition of the app pages​

🛈 NOTE: This is only needed if your app has multiple pages.

@app_startup begin
    add_page("/first-page")
    add_page("/second-page")
    add_page("/third-page")
end

2. Initialization of app persistent data​

App persistent data is an user defined data whose lifetime is the lifetime of the app, i.e., as long as the app is running the data will persist. App persistent data can be retrieved at any moment using get_app_data() and is shared accross sessions.

You can store data that you want to be globally available through all of your app's pages and sessions via the set_app_data() function, and retrieve it using the get_app_data() function. See App persistent data to learn more.

See also​