fix(report): use nix eval to list the components

This is less error prone than parsing the information from `nix flake
show`.

.editorconfig

@@ -2,7 +2,7 @@
 end_of_line = lf
 charset = utf-8
 
-[*.{nix,json,sh,js}]
+[*.{nix,json,sh}]
 indent_style = space
 indent_size = 2
 trim_trailing_whitespace = true

.forgejo/workflows/check.yml

@@ -8,7 +8,7 @@ jobs:
         check:
           - treefmt
     steps:
-      - uses: 'https://git.salame.cl/actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # v4
+      - uses: "https://git.salame.cl/actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683" # v4
       - name: Run checks
         run: |
           nix --version
@@ -18,25 +18,23 @@ jobs:
     runs-on: nixos
     needs: check
     steps:
-      - uses: 'https://git.salame.cl/actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # v4
+      - uses: "https://git.salame.cl/actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683" # v4
       - run: nix --version
       - name: Create Size Report
         uses: ./
         with:
-          system: x86_64-linux
           # Create a comment on the associated PR
-          comment-on-pr: ${{ github.ref_name != 'main' }}
+          comment-on-pr: 'false'
           # Generate artifacts on main (to speed up comparisons)
           # generate-artifact: ${{ github.ref_name == 'main' }}
           # Always generate artifacts for testing purposes
           generate-artifact: 'true'
-          # Generate comparisons to main
+          # This job's name (so we can find the previous artifacts)
-          do-comparison: 'true'
-          # This job's name (so we can find the artifacts)
           job-name: report-size
   report-download-check:
     runs-on: nixos
-    needs: report-size
+    needs: report-size-push
+    if: github.event_name == 'push'
     steps:
       - name: Download previous report
         uses: https://git.salame.cl/actions/download-artifact@d8d0a99033603453ad2255e58720b460a0555e1e # v4

.forgejo/workflows/renovate.yml

@@ -7,7 +7,7 @@ jobs:
   check-renovaterc:
     runs-on: nixos
     steps:
-      - uses: 'https://git.salame.cl/actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683' # v4
+      - uses: "https://git.salame.cl/actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683" # v4
       - name: Validate renovaterc.json
         run: |
           nix --version

.forgejo/workflows/test-pr.yml

@@ -0,0 +1,33 @@
+on:
+  pull_request:
+jobs:
+  report-size-pr:
+    runs-on: nixos
+    steps:
+      - uses: "https://git.salame.cl/actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683" # v4
+      - run: nix --version
+      - name: Create Size Report
+        uses: ./
+        with:
+          # Create a comment on the associated PR
+          comment-on-pr: 'true'
+          # Generate artifacts on main (to speed up comparisons)
+          # generate-artifact: ${{ github.ref_name == 'main' }}
+          # Always generate artifacts for testing purposes
+          generate-artifact: 'true'
+          # Generate comparisons to main
+          do-comparison: 'true'
+          # Get the previous artifacts from report-size-push (since those run on main)
+          job-name: report-size
+          artifact-name: report.json
+  report-download-check-pr:
+    runs-on: nixos
+    needs: report-size-pr
+    steps:
+      - name: Download previous report
+        uses: https://git.salame.cl/actions/download-artifact@d8d0a99033603453ad2255e58720b460a0555e1e # v4
+        with:
+          name: report.json
+      - name: Verify report exists
+        run: |
+          cat report.json

.gitattributes

@@ -1,3 +0,0 @@
-* text=auto eol=lf
-
-dist/** -diff linguist-generated=true

.gitignore

@@ -1,104 +1 @@
 result*
-
-# Dependency directory
-node_modules
-
-# Rest pulled from https://github.com/github/gitignore/blob/master/Node.gitignore
-# Logs
-logs
-*.log
-npm-debug.log*
-yarn-debug.log*
-yarn-error.log*
-lerna-debug.log*
-
-# Diagnostic reports (https://nodejs.org/api/report.html)
-report.[0-9]*.[0-9]*.[0-9]*.[0-9]*.json
-
-# Runtime data
-pids
-*.pid
-*.seed
-*.pid.lock
-
-# Directory for instrumented libs generated by jscoverage/JSCover
-lib-cov
-
-# Coverage directory used by tools like istanbul
-coverage
-*.lcov
-
-# nyc test coverage
-.nyc_output
-
-# Grunt intermediate storage (https://gruntjs.com/creating-plugins#storing-task-files)
-.grunt
-
-# Bower dependency directory (https://bower.io/)
-bower_components
-
-# node-waf configuration
-.lock-wscript
-
-# Compiled binary addons (https://nodejs.org/api/addons.html)
-build/Release
-
-# Dependency directories
-jspm_packages/
-
-# TypeScript v1 declaration files
-typings/
-
-# TypeScript cache
-*.tsbuildinfo
-
-# Optional npm cache directory
-.npm
-
-# Optional eslint cache
-.eslintcache
-
-# Optional REPL history
-.node_repl_history
-
-# Output of 'npm pack'
-*.tgz
-
-# Yarn Integrity file
-.yarn-integrity
-
-# dotenv environment variables file
-.env
-.env.test
-
-# parcel-bundler cache (https://parceljs.org/)
-.cache
-
-# next.js build output
-.next
-
-# nuxt.js build output
-.nuxt
-
-# vuepress build output
-.vuepress/dist
-
-# Serverless directories
-.serverless/
-
-# FuseBox cache
-.fusebox/
-
-# DynamoDB Local files
-.dynamodb/
-
-# OS metadata
-.DS_Store
-Thumbs.db
-
-# Ignore built ts files
-__tests__/runner/*
-
-# IDE files
-.idea
-*.code-workspace

.prettierignore

@@ -1,5 +0,0 @@
-.DS_Store
-.licenses/
-dist/
-node_modules/
-coverage/

.prettierrc.yml

@@ -1,15 +0,0 @@
-# See: https://prettier.io/docs/en/configuration
-printWidth: 80
-tabWidth: 2
-useTabs: false
-semi: false
-singleQuote: true
-quoteProps: as-needed
-jsxSingleQuote: false
-trailingComma: none
-bracketSpacing: true
-bracketSameLine: true
-arrowParens: always
-proseWrap: always
-htmlWhitespaceSensitivity: css
-endOfLine: lf

README.md

@@ -2,11 +2,9 @@
 
 Use `nix path-info` to query the size of flake outputs and produce a report.
 
-This repost can be posted to a PR (as formatted markdown) and/or uploaded as a
+This repost can be posted to a PR (as formatted markdown) and/or uploaded as a workflow artifact.
-workflow artifact.
 
-Requires `nix`, `jq`, `curl`, `sed`, `gunzip`, `tar` and `coreutils` to be in
+Requires `nix`, `jq`, `curl`, `sed`, `gunzip`, `tar` and `coreutils` to be in the runner's path.
-the runner's path.
 
 ## Example
 
@@ -41,32 +39,26 @@ For more details see the [action.yaml](./action.yml) file.
 **Definitions:**
 
 - `Name`: the name of the package/configuration.
-- `Size`: the closure size (size on disk/NAR size + all transitive
+- `Size`: the closure size (size on disk/NAR size + all transitive dependencies).
-  dependencies).
 - `NAR Size`: the size of the build output (package without the dependencies).
 - `[NAR] Size Change`: the amount changed compared to the main branch.
 
 **Tips on reading this data:**
 
-- For NixOS configurations you generally care only about the `Size` (closure
+- For NixOS configurations you generally care only about the `Size` (closure size/size on disk).
-  size/size on disk).
   - Reduce the `Size` by disabling unneeded services/default packages.
 - For Packages you care about both the `Size` and the `NAR Size`.
-  - Reduce the `NAR Size` by reducing the size of the build outputs, e.g. don't
+  - Reduce the `NAR Size` by reducing the size of the build outputs, e.g. don't copy unnecessary data to the $out dir, optimize binaries for size, etc.
-    copy unnecessary data to the $out dir, optimize binaries for size, etc.
   - Reduce the `Size` by reducing the dependencies (e.g. `buildInputs`).
-  - Don't worry too much about size, some dependencies are deduplicated, e.g.
+  - Don't worry too much about size, some dependencies are deduplicated, e.g. `glibc` adds ~40MiB to the `Size`, but is generally shared by ~every binary on the system, so, chances are, you are already including it from somewhere else and statically linking with e.g. `musl` is not gonna improve things.
-    `glibc` adds ~40MiB to the `Size`, but is generally shared by ~every binary
-    on the system, so, chances are, you are already including it from somewhere
-    else and statically linking with e.g. `musl` is not gonna improve things.
 
 # NixOS Configurations
 
-| Name     |  Size | Size Change | NAR Size | NAR Size Change |
+| Name | Size | Size Change | NAR Size | NAR Size Change |
-| -------- | ----: | ----------: | -------: | --------------: |
+|------|-----:|------------:|---------:|----------------:|
-| `gemini` |  11Gi |      -2.4Mi |     28Ki |               0 |
+| `gemini` | 11Gi | -2.4Mi | 28Ki | 0 |
-| `leo`    | 1.6Gi |           0 |     25Ki |               0 |
+| `leo` | 1.6Gi | 0 | 25Ki | 0 |
-| `libra`  | 9.4Gi |      -2.4Mi |     28Ki |               0 |
+| `libra` | 9.4Gi | -2.4Mi | 28Ki | 0 |
-| `taurus` | 7.6Gi |           0 |     34Ki |               0 |
+| `taurus` | 7.6Gi | 0 | 34Ki | 0 |
 
 </details>

action.yml

@@ -32,9 +32,6 @@ inputs:
 
       This is a no-op in case no PR is associated with the current branch.
     default: 'true'
-  system:
-    description: |
-      The nix system name to query the packages of (e.g. x86_64-linux)
   # Generate workflow artifact
   generate-artifact:
     description: Export the generated markdown document as a workflow artifact.
@@ -68,5 +65,58 @@ inputs:
     default: ${{ github.base_ref }}
 outputs:
 runs:
-  using: node20
+  using: 'composite'
-  main: dist/index.js
+  steps:
+    - name: Run
+      id: pr-number
+      env:
+        BASE_BRANCH: ${{ inputs.base-branch }}
+        COMMENT: ${{ inputs.comment-on-pr }}
+        DO_COMPARISON: ${{ inputs.do-comparison }}
+        GENERATE_ARTIFACT: ${{ inputs.generate-artifact }}
+        JOB_NAME: ${{ inputs.job-name }}
+      run: |
+        "$GITHUB_ACTION_PATH/scripts/run.sh"
+    - name: Find previous comment (if present)
+      # We want to generate a comment and we we able to find the PR number
+      if: inputs.comment-on-pr == 'true' && steps.pr-number.outputs.pr-number != ''
+      id: find-comment
+      uses: https://github.com/peter-evans/find-comment@3eae4d37986fb5a8592848f6a574fdf654e61f9e # v3
+      with:
+        issue-number: ${{ steps.pr-number.outputs.pr-number }}
+        direction: first
+        body-includes: "<!-- AUTOGENERATED by nix-flake-outputs-size action -->"
+    - name: Create report and comment on PR
+      # We want to generate a comment and we we able to find the PR number
+      if: inputs.comment-on-pr == 'true' && steps.pr-number.outputs.pr-number != ''
+      env:
+        ARTIFACT_NAME: ${{ inputs.artifact-name }}
+        BASE_BRANCH: ${{ inputs.base-branch }}
+        COMMENT_ID: ${{ steps.find-comment.outputs.comment-id }}
+        DO_COMPARISON: ${{ inputs.do-comparison }}
+        JOB_NAME: ${{ inputs.job-name }}
+        PR_ID: ${{ steps.pr-number.outputs.pr-number }}
+      run: |
+        . "$GITHUB_ACTION_PATH/scripts/utils.sh"
+
+        # Try to do a comparison report
+        if [ "$DO_COMPARISON" = 'true' ]; then
+          if "$GITHUB_ACTION_PATH/scripts/retrieve-old-report.sh" && [ -f old-report.json ]; then
+            log "Reporting on sizes and comparing to sizes in $BASE_BRANCH"
+
+            "$GITHUB_ACTION_PATH/scripts/comment_on_pr.sh" report.json old-report.json
+            exit 0
+          else
+            error 'Failed to do comparison, fallback to posting the report without them'
+          fi
+        fi
+
+        # Just report values
+        log 'Reporting on sizes'
+        "$GITHUB_ACTION_PATH/scripts/comment_on_pr.sh" report.json
+    - name: Upload Artifact
+      uses: https://git.salame.cl/actions/upload-artifact@v4
+      if: inputs.generate-artifact == 'true'
+      with:
+        path: report.json
+        name: ${{ inputs.artifact-name }}

eslint.config.mjs

@@ -1,61 +0,0 @@
-// See: https://eslint.org/docs/latest/use/configure/configuration-files
-
-import { fixupPluginRules } from '@eslint/compat'
-import { FlatCompat } from '@eslint/eslintrc'
-import js from '@eslint/js'
-import _import from 'eslint-plugin-import'
-import jest from 'eslint-plugin-jest'
-import prettier from 'eslint-plugin-prettier'
-import globals from 'globals'
-import path from 'node:path'
-import { fileURLToPath } from 'node:url'
-
-const __filename = fileURLToPath(import.meta.url)
-const __dirname = path.dirname(__filename)
-const compat = new FlatCompat({
-  baseDirectory: __dirname,
-  recommendedConfig: js.configs.recommended,
-  allConfig: js.configs.all
-})
-
-export default [
-  {
-    ignores: ['**/coverage', '**/dist', '**/linter', '**/node_modules']
-  },
-  ...compat.extends(
-    'eslint:recommended',
-    'plugin:jest/recommended',
-    'plugin:prettier/recommended'
-  ),
-  {
-    plugins: {
-      import: fixupPluginRules(_import),
-      jest,
-      prettier
-    },
-
-    languageOptions: {
-      globals: {
-        ...globals.node,
-        ...globals.jest,
-        Atomics: 'readonly',
-        SharedArrayBuffer: 'readonly'
-      },
-
-      ecmaVersion: 2023,
-      sourceType: 'module'
-    },
-
-    rules: {
-      camelcase: 'off',
-      'eslint-comments/no-use': 'off',
-      'eslint-comments/no-unused-disable': 'off',
-      'i18n-text/no-en': 'off',
-      'import/no-namespace': 'off',
-      'no-console': 'off',
-      'no-shadow': 'off',
-      'no-unused-vars': 'off',
-      'prettier/prettier': 'error'
-    }
-  }
-]

flake.nix

@@ -26,12 +26,10 @@
           # Setup formatters
           treefmt = {
             # Ignore images
-            settings.global.excludes = [
+            settings.global.excludes = [ "*.png" ];
-              "*.png"
-              "dist/*"
-            ];
             projectRootFile = "flake.nix";
             programs = {
+              mdformat.enable = true;
               nixfmt.enable = true;
               shfmt.enable = true;
               shellcheck.enable = true;

jest.config.js

@@ -1,30 +0,0 @@
-// See: https://jestjs.io/docs/configuration
-
-/** @type {import('jest').Config} */
-const jestConfig = {
-  clearMocks: true,
-  collectCoverage: true,
-  collectCoverageFrom: ['./src/**'],
-  coverageDirectory: './coverage',
-  coveragePathIgnorePatterns: ['/node_modules/', '/dist/'],
-  coverageReporters: ['json-summary', 'text', 'lcov'],
-  // Uncomment the below lines if you would like to enforce a coverage threshold
-  // for your action. This will fail the build if the coverage is below the
-  // specified thresholds.
-  // coverageThreshold: {
-  //   global: {
-  //     branches: 100,
-  //     functions: 100,
-  //     lines: 100,
-  //     statements: 100
-  //   }
-  // },
-  moduleFileExtensions: ['js'],
-  reporters: ['default'],
-  testEnvironment: 'node',
-  testMatch: ['**/*.test.js'],
-  testPathIgnorePatterns: ['/dist/', '/node_modules/'],
-  verbose: true
-}
-
-export default jestConfig

package.json

@@ -1,66 +0,0 @@
-{
-  "name": "nix-flake-outputs-size-report",
-  "description": "Use 'nix-path-info' to query the size of outputs and produce a markdown report",
-  "version": "0.1.0",
-  "author": "Jalil David Salamé Messina",
-  "type": "module",
-  "private": true,
-  "homepage": "https://git.salame.cl/jalil/nix-flake-outputs-size#readme",
-  "repository": {
-    "type": "git",
-    "url": "git+https://git.salame.cl/jalil/nix-flake-outputs-size.git"
-  },
-  "bugs": {
-    "url": "https://git.salame.cl/jalil/nix-flake-outputs-size/issues"
-  },
-  "keywords": [
-    "actions"
-  ],
-  "exports": {
-    ".": "./dist/index.js"
-  },
-  "engines": {
-    "node": ">=20"
-  },
-  "scripts": {
-    "bundle": "npm run format:write && npm run package",
-    "ci-test": "NODE_OPTIONS=--experimental-vm-modules NODE_NO_WARNINGS=1 npx jest",
-    "coverage": "npx make-coverage-badge --output-path ./badges/coverage.svg",
-    "format:write": "npx prettier --write .",
-    "format:check": "npx prettier --check .",
-    "lint": "npx eslint .",
-    "local-action": "npx @github/local-action . src/main.js .env",
-    "package": "npx rollup --config rollup.config.js",
-    "package:watch": "npm run package -- --watch",
-    "test": "NODE_OPTIONS=--experimental-vm-modules NODE_NO_WARNINGS=1 npx jest",
-    "all": "npm run format:write && npm run lint && npm run test && npm run coverage && npm run package"
-  },
-  "license": "MIT",
-  "dependencies": {
-    "@actions/artifact": "^2.3.2",
-    "@actions/core": "^1.11.1",
-    "@actions/exec": "^1.1.1",
-    "@actions/github": "^6.0.1"
-  },
-  "devDependencies": {
-    "@eslint/compat": "^1.3.1",
-    "@github/local-action": "^3.2.1",
-    "@jest/globals": "^30.0.4",
-    "@rollup/plugin-commonjs": "^28.0.6",
-    "@rollup/plugin-json": "^6.1.0",
-    "@rollup/plugin-node-resolve": "^16.0.1",
-    "eslint": "^9.30.1",
-    "eslint-config-prettier": "^10.1.5",
-    "eslint-plugin-import": "^2.32.0",
-    "eslint-plugin-jest": "^29.0.1",
-    "eslint-plugin-prettier": "^5.5.1",
-    "jest": "^30.0.4",
-    "make-coverage-badge": "^1.2.0",
-    "prettier": "^3.6.2",
-    "prettier-eslint": "^16.4.2",
-    "rollup": "^4.44.2"
-  },
-  "optionalDependencies": {
-    "@rollup/rollup-linux-x64-gnu": "*"
-  }
-}

report.json

@@ -1,11 +0,0 @@
-{
-  "packages": [
-    {
-      "name": "hello",
-      "size": 33159640,
-      "narSize": 234680
-    }
-  ],
-  "nixosConfigurations": [],
-  "homeConfigurations": []
-}

rollup.config.js

@@ -1,18 +0,0 @@
-// See: https://rollupjs.org/introduction/
-
-import commonjs from '@rollup/plugin-commonjs'
-import json from '@rollup/plugin-json'
-import { nodeResolve } from '@rollup/plugin-node-resolve'
-
-const config = {
-  input: 'src/index.js',
-  output: {
-    esModule: true,
-    file: 'dist/index.js',
-    format: 'es',
-    sourcemap: true
-  },
-  plugins: [commonjs(), json(), nodeResolve({ preferBuiltins: true })]
-}
-
-export default config

scripts/create-report.sh

@@ -7,24 +7,25 @@ util_path="${GITHUB_ACTION_PATH:-.}/scripts/utils.sh"
 # shellcheck source=scripts/utils.sh
 . "${util_path}"
 
-group 'Retrieving Flake information'
-flake_info=$(nix flake show --json --quiet --quiet)
-endgroup
-
 system=$(nix eval --impure --json --expr 'builtins.currentSystem')
 
-group 'Show Packages'
+# Extract the names of a flake attrset
-packages=$(echo "$flake_info" | jq --raw-output --argjson system "$system" 'getpath(["packages", $system]) | select(. != null) | keys[]')
+get_names() {
+  nix eval --json --apply builtins.attrNames "$1" 2>/dev/null | jq --raw-output '.[]'
+}
+
+group "Show Packages for $system"
+packages=$(get_names .#packages."$system")
 [ -z "$packages" ] || log "$packages"
 endgroup
 
 group 'Show Home Manager Configurations'
-hmConfigs=$(echo "$flake_info" | jq --raw-output '.homeConfigurations | select(. != null) | keys[]')
+hmConfigs=$(get_names .#homeConfigurations)
 [ -z "$hmConfigs" ] || log "$hmConfigs"
 endgroup
 
 group 'Show NixOS Configurations'
-nixosConfigs=$(echo "$flake_info" | jq --raw-output '.nixosConfigurations | select(. != null) | keys[]')
+nixosConfigs=$(get_names .#nixosConfigurations)
 [ -z "$nixosConfigs" ] || log "$nixosConfigs"
 endgroup
 
@@ -51,7 +52,7 @@ pkgs_json() {
 hm_configs_json() {
   for config in $hmConfigs; do
     log "Building $config"
-    path=$(nix build --print-out-paths ".#homeConfigurations.$config.activationPackages")
+    path=$(nix build --print-out-paths ".#homeConfigurations.$config.config.home.activationPackage")
     closure_size "$config" "$path"
   done
 }

scripts/retrieve-old-report.sh

@@ -40,7 +40,9 @@ has_report() {
 # If a base branch is not provided, use the default branch
 base_branch=${BASE_BRANCH:-$(default_branch)}
 
-if [ "$(in_private_repo)" != 'true' ] && [ "$JOB_NAME" ]; then
+if in_private_repo; then
+  warn 'Detected that this is a private repo cannot retrieve old report'
+elif [ "$JOB_NAME" ]; then
   url=$(base_report_url "$base_branch")
 
   log "Found previous run at: $url"
@@ -56,13 +58,14 @@ if [ "$(in_private_repo)" != 'true' ] && [ "$JOB_NAME" ]; then
     exit 0
   fi
   error "Failed to find previous report, expected at: $report_url"
+else
+  panic 'job-name is missing, therefore we cannot find the previous report'
 fi
 
-warn "Couldn't retrieve old report:"
+warn "Couldn't retrieve old report:
-warn '    This usuially happens when running on private repos'
+  note: This usually happens when running on private repos or when job-name is not set.
-warn '    or when job-name is not set.'
+
-warn
+        See the README for more details"
-warn '    See the README for more details'
 
 error "Falling back to slow method (checkout $base_branch and generate the report)"
 

scripts/run.sh

@@ -0,0 +1,61 @@
+#!/bin/sh
+
+. "$GITHUB_ACTION_PATH/scripts/utils.sh"
+
+# Input validation
+if [ "$COMMENT" != "true" ] && [ "$GENERATE_ARTIFACT" != "true" ]; then
+  panic 'Neither comment-on-pr nor generate-artifact is set
+    note: this looks like an error; if it isn'"'"'t disable this action with "step.if"'
+fi
+
+if [ "$DO_COMPARISON" = 'true' ] && [ -z "$JOB_NAME" ]; then
+  panic 'Requested a comparison report but job-name wasn'"'"'t set'
+fi
+
+# Create Size Report (will be uploaded by the upload-artifact action)
+"$GITHUB_ACTION_PATH/scripts/create-report.sh" report.json
+
+# Nothing else to do
+if [ "$COMMENT" != "true" ]; then exit 0; fi
+
+# Find the PR for this commit so we can post a comment on it
+pr_number=
+case "$GITHUB_EVENT_NAME" in
+"pull_request")
+  pr_number=$(jq .number "$GITHUB_EVENT_PATH")
+  log "Triggered by a pull request with index: $pr_number"
+  ;;
+"push")
+  log "Triggered by a push to $GITHUB_REF_NAME autodetecting PR number"
+
+  log "Get PR number for $GITHUB_REF_NAME"
+  prs=$(curl -X 'GET' \
+    "$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/pulls?state=open&sort=recentupdate" \
+    -H "Authorization: token $GITHUB_TOKEN" \
+    -H 'Accept: application/json')
+
+  log "Found these open PRs: $(echo "$prs" | jq '[.[] | .number]')"
+
+  pr_number=$(echo "$prs" |
+    jq --arg ref "$GITHUB_REF_NAME" '.[] | select(.head.ref == $ref) | .number')
+
+  # Protect against running before a PR is made or if it is triggered on the main branch
+  if [ -z "$pr_number" ]; then
+    warn "No PR created for this commit"
+    exit 0
+  fi
+
+  log "The PR we found for $GITHUB_REF_NAME is $pr_number"
+  ;;
+*)
+  panic "Unexpected event $GITHUB_EVENT_NAME for commenting on a PR, expected push or pull_request"
+  ;;
+esac
+
+log "Expected PR URL: $GITHUB_SERVER_URL/$GITHUB_REPOSITORY/pulls/$pr_number"
+
+# This seems to create the file???
+log "GITHUB_OUTPUT=$GITHUB_OUTPUT"
+log "$(ls -l "$GITHUB_OUTPUT")"
+
+echo "pr-number=$pr_number" >>"$GITHUB_OUTPUT"

scripts/utils.sh

@@ -12,6 +12,11 @@ error() {
   log "\e[0;31m[WARN]:" "$@" "\e[0m"
 }
 
+panic() {
+  error "$@"
+  exit 1
+}
+
 group() {
   echo "::group::$1"
 }

src/index.js

@@ -1,8 +0,0 @@
-/**
- * The entrypoint for the action. This file simply imports and runs the action's
- * main logic.
- */
-import { run } from './main.js'
-
-/* istanbul ignore next */
-run()

src/main.js

@@ -1,145 +0,0 @@
-import * as core from '@actions/core'
-import * as exec from '@actions/exec'
-import * as github from '@actions/github'
-import { DefaultArtifactClient } from '@actions/artifact'
-import * as fs from 'node:fs/promises'
-
-/**
- * The main function for the action.
- *
- * @returns {Promise<void>} Resolves when the action is complete.
- */
-export async function run() {
-  try {
-    const comment = core.getBooleanInput('comment-on-pr', { required: false })
-    const upload = core.getBooleanInput('generate-artifact', {
-      required: false
-    })
-    const artifactName = core.getInput('artifact-name', { required: false })
-    const compare = core.getBooleanInput('do-comparison', { required: false })
-    const jobName = core.getInput('job-name', { required: false })
-    const baseBranch = core.getInput('base-branch', { required: false })
-    const system = core.getInput('system', { required: true })
-
-    if (!comment && !upload) {
-      core.error(
-        'Both comment-on-pr and generate-artifact were set to false, nothing to do, consider disabling the action instead'
-      )
-      core.setFailed('Neither commenting nor uploading a report ... why?')
-      return
-    }
-
-    const flakeInfo = JSON.parse(
-      await collectOutput('nix', ['flake', 'show', '--json'])
-    )
-    core.debug(`nix flake show --json: ${flakeInfo}`)
-
-    const report = await core.group('Generating size report', () =>
-      generateReport(flakeInfo, system)
-    )
-
-    if (upload) {
-      const artifact = new DefaultArtifactClient()
-      await fs.writeFile(artifactName, JSON.stringify(report))
-      const { id, size } = artifact.uploadArtifact(artifactName, [artifactName])
-
-      core.info(`Uploaded report ${artifactName} (${size}B) with id ${id}`)
-    }
-
-    // Done
-    if (!comment) {
-      return
-    }
-
-    // TODO: compare reports and create comment
-  } catch (error) {
-    // Fail the workflow run if an error occurs
-    if (error instanceof Error) core.setFailed(error.message)
-  }
-}
-
-async function generateReport(flakeInfo, system) {
-  const packages = getPackages(flakeInfo, system)
-  const hmConfigs = getKeys(flakeInfo, 'homeConfigurations')
-  const nixosConfigs = getKeys(flakeInfo, 'nixosConfigurations')
-
-  core.info(`packages: ${packages}`)
-  core.info(`homeConfigurations: ${hmConfigs}`)
-  core.info(`nixosConfigurations: ${nixosConfigs}`)
-
-  const pkgSizes = await core.group('Calculating size of packages', () =>
-    calculateSizeOf(packages, (pkg) => `.#${pkg}`)
-  )
-
-  const hmConfigsSizes = await core.group(
-    'Calculating size of Home-Manager Configurations',
-    () =>
-      calculateSizeOf(
-        hmConfigs,
-        (config) => `.#homeConfigurations.${config}.activationPackages`
-      )
-  )
-
-  const nixosConfigsSizes = await core.group(
-    'Calculating size of NixOS Configurations',
-    () =>
-      calculateSizeOf(
-        nixosConfigs,
-        (config) =>
-          `.#nixosConfigurations.${config}.config.system.build.toplevel`
-      )
-  )
-
-  return {
-    packages: pkgSizes,
-    nixosConfigurations: nixosConfigsSizes,
-    homeConfigurations: hmConfigsSizes
-  }
-}
-
-async function calculateSizeOf(names, nameToInstallable) {
-  let sizes = []
-  for (const name of names) {
-    sizes.push(await calculateSize(nameToInstallable(name)))
-  }
-  return sizes
-}
-
-/**
- * Get the packages from a `nix flake show --json` blob
- *
- * @returns {Array<String>} the packages in the current flake for the specific system
- */
-function getPackages(flakeInfo, system) {
-  return 'packages' in flakeInfo ? getKeys(flakeInfo.packages, system) : []
-}
-
-function getKeys(flakeInfo, key) {
-  return key in flakeInfo ? Object.keys(flakeInfo[key]) : []
-}
-
-async function calculateSize(installable) {
-  const path = await collectOutput('nix', [
-    'build',
-    '--print-out-paths',
-    installable
-  ])
-  const data = JSON.parse(
-    await collectOutput('nix', ['path-info', '--closure-size', '--json', path])
-  )
-  data.path = path
-
-  return data
-}
-
-async function collectOutput(cmd, args) {
-  let output = ''
-  await exec.exec(cmd, args, {
-    listeners: {
-      stdout: (data) => {
-        output += data.toString()
-      }
-    }
-  })
-  return output.trim()
-}