What is the best way to store globally accessible "heavy" objects?

In Flask we have a g global context to keep the global variables of the request. A kind of canonical example from the docs:

from flask import g

def get_db():
    if 'db' not in g:
        g.db = connect_to_database()

    return g.db

@app.teardown_appcontext
def teardown_db():
    db = g.pop('db', None)

    if db is not None:
        db.close()

So I wonder if there is something similar in starlette? I have a couple of very weighty objects which I don’t want to initialize too often. These objects are “read-only” and are not modified during app’s lifetime. What is the best way to handle cases like this?

[tomchristie]

These objects are “read-only” and are not modified during app’s lifetime.

Depends on if you’re asking about “during app’s lifetime” or “during the request/response cycle”.

(Flask’s g object is for storing data associated with the current request/response cycle.)

For stuff that has a request/response lifespan, you can store arbitrary stuff on the request “scope”. request["foo"] = whatever().

For lifespan, use globals, with @app.on_event('startup')/@app.on_event('shutdown') to setup and teardown any network connections or other resources.

[tomchristie]

Happy to dig further into any specific questions around this too. (And consider if we end up wanting any helpers for task-local context)