Context

The Context is a beauty of an object unique to Esmerald. The context is a parameter that can be used inside the handlers only and provides additional information to your handler that you might need for any particular reason.

Importing is as simple as:

from esmerald import Context

API Reference

You can learn more about the Context by checking the API Reference.

The Context

You can see the context as the request context of a given handler. This also means, when a handler is declared all the information passed to it is automatically accessible via context.handler parameter.

The context also provides access to the request object as well as the application settings and other functions.

This means, if you want to pass a request and context you actually only need the context directly as the request is already available inside but you can still pass both anyway.

Example

from esmerald import Context, Esmerald, Gateway, get


@get("/users/{id}")
def read_context(context: Context, id: str):
    host = context.request.client.host

    context_data = context.get_context_data()
    context.add_to_context("name", "Esmerald")

    context_data = context.get_context_data()
    context_data.update({
        "host": host, "user_id": id
    })
    return context_data


app = Esmerald(
    routes=[
        Gateway(handler=read_request)
    ]
)

The context can be particularly useful if you want to access handler information that is not available after the handler is instantiated, for example and can be very useful if you also want to access the context.settings where the application settings are available, another versatile way of accessing them.