function

 1# Copyright 2025 The Crossplane Authors.
 2#
 3# Licensed under the Apache License, Version 2.0 (the "License");
 4# you may not use this file except in compliance with the License.
 5# You may obtain a copy of the License at
 6#
 7#     http://www.apache.org/licenses/LICENSE-2.0
 8#
 9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14
15"""Python SDK for writing Crossplane composition functions.
16
17This SDK provides the building blocks for implementing [Crossplane composition
18functions](https://docs.crossplane.io/latest/concepts/composition-functions) in
19Python. Composition functions are serverless components that extend Crossplane's
20composition capability, allowing you to programmatically control how infrastructure
21is composed and managed.
22
23## Quick Start
24
25Install the SDK:
26
27```shell
28pip install crossplane-function-sdk-python
29```
30
31Create a composition function by subclassing `Runtime`:
32
33```python
34from crossplane.function.runtime import Runtime
35from crossplane.function.request import RunFunctionRequest
36from crossplane.function.response import RunFunctionResponse
37
38
39class MyFunction(Runtime):
40    def Run(self, request: RunFunctionRequest) -> RunFunctionResponse:
41        # Your composition logic here
42        return response.to(request)
43```
44
45## Modules
46
47- **runtime** — Base class for implementing the function runtime and gRPC server.
48- **request** — Types and utilities for parsing `RunFunctionRequest` messages.
49- **response** — Types and utilities for building `RunFunctionResponse` messages.
50- **resource** — Kubernetes resource types used in function pipelines.
51- **logging** — Structured logging utilities for function output.
52
53## Protobuf Types
54
55The `RunFunctionRequest` and `RunFunctionResponse` types are generated from
56proto3 schema definitions. See the proto modules for API reference:
57
58- [`proto.v1.run_function_pb2`][crossplane.function.proto.v1.run_function_pb2]
59  — Current API
60- [`proto.v1beta1.run_function_pb2`][crossplane.function.proto.v1beta1.run_function_pb2]
61  — Legacy API
62
63Proto-generated fields behave like standard Python types but follow
64[protobuf Python conventions](https://protobuf.dev/reference/python/python-generated/).
65"""