rust-affected

A GitHub Action that detects which packages in a Rust workspace are affected by a set of changed files, using the Cargo dependency graph.

Given a set of changed files, it determines:

• changed_crates — packages with files directly modified
• affected_library_members — pure library crates that are changed or (transitively) depend on a changed crate; binary crates are excluded from this list
• affected_binary_members — affected crates that have a binary target; mutually exclusive with affected_library_members
• force_all — whether a configured force-trigger file changed, meaning the entire workspace should be considered affected

Usage

jobs:
  plan:
    runs-on: ubuntu-latest
    outputs:
      affected_binary_members: ${{ steps.affected.outputs.affected_binary_members }}
      force_all: ${{ steps.affected.outputs.force_all }}
    steps:
      - uses: actions/checkout@v4

      - name: Get changed files
        id: changed
        uses: tj-actions/changed-files@v47

      - name: Detect affected packages
        id: affected
        uses: robertrautenbach/rust-affected@v4.0.3
        with:
          changed_files: ${{ steps.changed.outputs.all_changed_files }}
          force_triggers: |
            Cargo.lock
            Cargo.toml
            rust-toolchain.toml
            .cargo/config.toml
            .github/

  deploy:
    needs: plan
    if: contains(needs.plan.outputs.affected_binary_members, 'my-service') || needs.plan.outputs.force_all == 'true'
    runs-on: ubuntu-latest
    steps:
      - run: echo "Deploying my-service"

Example output

Imagine a workspace where lib-utils is a shared library depended on by lib-core, lib-core-ext, app-alpha, app-beta, and tool-alpha. A PR that changes lib-utils/src/lib.rs produces:

changed_crates=["lib-utils"]
affected_library_members=["lib-core","lib-core-ext","lib-utils"]
affected_binary_members=["app-alpha","app-beta","tool-alpha"]
force_all=false

The action also writes a job summary to the workflow run:

rust-affected

	Crates
Changed	lib-utils
Affected libraries	lib-core lib-core-ext lib-utils
Affected binaries	app-alpha app-beta tool-alpha

Changed crates

• lib-utils

Affected library members

• lib-core
• lib-core-ext
• lib-utils

Affected binary members

• app-alpha
• app-beta
• tool-alpha

Getting changed files

You provide the list of changed files — here are common approaches:

tj-actions/changed-files

- name: Get changed files
  id: changed
  uses: tj-actions/changed-files@v47

- uses: robertrautenbach/rust-affected@v4.0.3
  with:
    changed_files: ${{ steps.changed.outputs.all_changed_files }}

git diff (no extra dependencies)

- name: Get changed files
  id: changed
  run: |
    echo "files=$(git diff --name-only ${{ github.event.pull_request.base.sha }}..HEAD | tr '\n' ' ')" >> "$GITHUB_OUTPUT"

- uses: robertrautenbach/rust-affected@v4.0.3
  with:
    changed_files: ${{ steps.changed.outputs.files }}

Note: Requires fetch-depth: 0 on actions/checkout so the base SHA is available locally.

Inputs

Input	Required	Description
changed_files	Yes	Space- or newline-separated list of changed file paths relative to the workspace root.
force_triggers	No	Space- or newline-separated list of glob patterns that trigger a full rebuild when any matching file changes. Supports *, **, and ?. A bare name (e.g. Cargo.lock) matches that exact path only. A trailing slash (e.g. .github/) matches the directory and everything inside it. Full globs are also supported (e.g. **/*.sql, migrations/**). If omitted, force_all is never set.
excluded_members	No	Space- or newline-separated list of workspace member names or path prefixes to exclude from all outputs. A plain name (e.g. my-tool) matches the crate name directly. An entry containing / is matched against the crate's directory relative to the workspace root: a trailing slash (e.g. tools/) excludes every crate under that directory, while an exact relative path (e.g. tools/my-tool) excludes only that crate. Useful for internal tooling or helper crates that should never appear in CI results. If omitted, no members are excluded.

Outputs

Output	Description
changed_crates	JSON array of crate names with directly changed files
affected_library_members	JSON array of affected workspace members that are pure library crates (no binary target)
affected_binary_members	JSON array of affected workspace members that have a binary target; mutually exclusive with affected_library_members
force_all	"true" if a force-trigger file changed, otherwise "false"

Migrating from v3

v4 is a breaking change. The action no longer detects changed files itself — you provide them via the changed_files input.

v3	v4
base_sha input (optional)	Removed — compute your own diff
Changed files detected automatically	changed_files input (required)
All outputs	Unchanged

Before (v3):

- uses: robertrautenbach/rust-affected@v4.0.3

After (v4):

- name: Get changed files
  id: changed
  uses: tj-actions/changed-files@v47

- uses: robertrautenbach/rust-affected@v4.0.3
  with:
    changed_files: ${{ steps.changed.outputs.all_changed_files }}