HTTP

grelmicro is not a web framework. These are the pieces that decide what your service puts on the wire, whichever framework you picked.

Page	What it covers
Where a rule applies	include, exclude, what wins, and how to read it back. Learn it once for all of them.
Error Responses	Every rejection answered in one standard format, RFC 9457 or TM Forum.
Conditional Requests	ETag on reads, If-Match on writes, so a write cannot erase a change it never saw.
Idempotency Middleware	A repeated Idempotency-Key replays the stored response instead of running the operation again.
Response Cache	A repeated read is answered from the store instead of the handler, once per key across replicas.
Rate Limit	A caller over its budget is turned away at the edge, and told what it has left.
Ops Server	The health and metrics endpoints on a port of their own, for a process that serves no HTTP.

The Idempotency page covers the same pattern away from HTTP, as a block or a decorator around any operation.

One more HTTP piece lives with the concern it belongs to: Client IP resolves the real caller behind a reverse proxy, which is a trust decision before it is an HTTP one.

Each of them is a component you register:

micro = Grelmicro(
    uses=[
        ErrorResponses(),
        ConditionalRequests(),
        IdempotentRequests(),
    ]
)
micro.install(app)

Nothing happens without the component. grelmicro installs into a framework you chose, so it changes nothing about how that framework answers until you ask.

Every one of them takes include and exclude to say which paths it acts on. The response cache, the rate limiter and the access log are tuned from a mounted ConfigMap while the service runs. Conditional and idempotent requests are configured at startup, because what they protect is not a thing to change without a deploy. Where a rule applies covers both, once, for all of them.

Every one of them is pure ASGI underneath, so it runs on FastAPI, Starlette, and Litestar alike, and a framework that serves no HTTP simply skips it. Read Frameworks for what that means.