Merge pull request #34 from DeterminateSystems/hoverbear/ds-893-make-installer-action-use-typescript

Typescript rewrite

.eslintrc.json

@@ -0,0 +1,74 @@
+{
+    "plugins": [
+        "@typescript-eslint"
+    ],
+    "extends": [
+        "plugin:github/recommended"
+    ],
+    "parser": "@typescript-eslint/parser",
+    "parserOptions": {
+        "ecmaVersion": 9,
+        "sourceType": "module",
+        "project": "./tsconfig.json"
+    },
+    "rules": {
+        "i18n-text/no-en": "off",
+        "eslint-comments/no-use": "off",
+        "import/no-namespace": "off",
+        "no-unused-vars": "off",
+        "@typescript-eslint/no-unused-vars": [
+            "error",
+            {
+                "argsIgnorePattern": "^_"
+            }
+        ],
+        "@typescript-eslint/explicit-member-accessibility": [
+            "error",
+            {
+                "accessibility": "no-public"
+            }
+        ],
+        "@typescript-eslint/no-require-imports": "error",
+        "@typescript-eslint/array-type": "error",
+        "@typescript-eslint/await-thenable": "error",
+        "@typescript-eslint/ban-ts-comment": "error",
+        "camelcase": "off",
+        "@typescript-eslint/consistent-type-assertions": "error",
+        "@typescript-eslint/explicit-function-return-type": [
+            "error",
+            {
+                "allowExpressions": true
+            }
+        ],
+        "@typescript-eslint/func-call-spacing": [
+            "error",
+            "never"
+        ],
+        "@typescript-eslint/no-array-constructor": "error",
+        "@typescript-eslint/no-empty-interface": "error",
+        "@typescript-eslint/no-explicit-any": "error",
+        "@typescript-eslint/no-extraneous-class": "error",
+        "@typescript-eslint/no-for-in-array": "error",
+        "@typescript-eslint/no-inferrable-types": "error",
+        "@typescript-eslint/no-misused-new": "error",
+        "@typescript-eslint/no-namespace": "error",
+        "@typescript-eslint/no-non-null-assertion": "warn",
+        "@typescript-eslint/no-unnecessary-qualifier": "error",
+        "@typescript-eslint/no-unnecessary-type-assertion": "error",
+        "@typescript-eslint/no-useless-constructor": "error",
+        "@typescript-eslint/no-var-requires": "error",
+        "@typescript-eslint/prefer-for-of": "warn",
+        "@typescript-eslint/prefer-function-type": "warn",
+        "@typescript-eslint/prefer-includes": "error",
+        "@typescript-eslint/prefer-string-starts-ends-with": "error",
+        "@typescript-eslint/promise-function-async": "error",
+        "@typescript-eslint/require-array-sort-compare": "error",
+        "@typescript-eslint/restrict-plus-operands": "error",
+        "@typescript-eslint/type-annotation-spacing": "error",
+        "@typescript-eslint/unbound-method": "error"
+    },
+    "env": {
+        "node": true,
+        "es6": true
+    }
+}

.github/workflows/ci.yml

@@ -17,7 +17,6 @@ jobs:
           logger: pretty
           log-directives: nix_installer=trace
           backtrace: full
-          nix-installer-branch: main
       - name: echo $PATH
         run: echo $PATH
       - name: Test `nix` with `$GITHUB_PATH`
@@ -42,7 +41,6 @@ jobs:
           logger: pretty
           log-directives: nix_installer=trace
           backtrace: full
-          nix-installer-branch: main
       - name: Test `nix` with `$GITHUB_PATH`
         if: success() || failure()
         run: |
@@ -60,7 +58,6 @@ jobs:
           reinstall: true
           extra-conf: |
             use-sqlite-wal = true
-          nix-installer-branch: main
       - name: Test `nix` with `$GITHUB_PATH`
         if: success() || failure()
         run: |
@@ -86,7 +83,6 @@ jobs:
           logger: pretty
           log-directives: nix_installer=trace
           backtrace: full
-          nix-installer-branch: main
       - name: echo $PATH
         run: echo $PATH
       - name: Test `nix` with `$GITHUB_PATH`
@@ -115,7 +111,6 @@ jobs:
           logger: pretty
           log-directives: nix_installer=trace
           backtrace: full
-          nix-installer-branch: main
       - name: Test `nix` with `$GITHUB_PATH`
         if: success() || failure()
         run: |
@@ -133,7 +128,6 @@ jobs:
           reinstall: true
           extra-conf: |
             use-sqlite-wal = true
-          nix-installer-branch: main
       - name: Test `nix` with `$GITHUB_PATH`
         if: success() || failure()
         run: |

.gitignore

@@ -0,0 +1,99 @@
+# 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/*
+lib/**/*

.prettierignore

@@ -0,0 +1,3 @@
+dist/
+lib/
+node_modules/

.prettierrc.json

@@ -0,0 +1 @@
+{}

action.yml

@@ -20,7 +20,7 @@ inputs:
     description: "The init system to configure, requires `planner: linux-multi` (allowing the choice between `none` or `systemd`)"
     required: false
   local-root:
-    description: A local `nix-installer` binary root, overrides the `nix-installer-url` setting (a `nix-installer.sh` script should exist, binaries should be named `nix-installer-$ARCH`, eg. `nix-installer-x86_64-linux`)
+    description: A local `nix-installer` binary root, overrides any settings which change the `nix-installer` used (binaries should be named `nix-installer-$ARCH-$OS`, eg. `nix-installer-x86_64-linux`)
     required: false
   log-directives:
     description: A list of Tracing directives, comma separated, `-`s replaced with `_` (eg. `nix_installer=trace`, see https://docs.rs/tracing-subscriber/latest/tracing_subscriber/filter/struct.EnvFilter.html#directives)
@@ -31,7 +31,7 @@ inputs:
   ssl-cert-file:
     description: "An SSL cert to use (if any), used for fetching Nix and sets `NIX_SSL_CERT_FILE` for Nix"
     required: false
-  pproxy:
+  proxy:
     description: "The proxy to use (if any), valid proxy bases are `https://$URL`, `http://$URL` and `socks5://$URL`"
     required: false
   mac-case-sensitive:
@@ -49,6 +49,7 @@ inputs:
   modify-profile:
     description: Modify the user profile to automatically load nix
     required: false
+    default: true
   nix-build-group-id:
     description: The Nix build group GID
     required: false
@@ -88,9 +89,11 @@ inputs:
   reinstall:
     description: Force a reinstall if an existing installation is detected (consider backing up `/nix/store`)
     required: false
+    default: false
   start-daemon:
-    description: "If the daemon should be started, requires `planner: linux-multi`"
+    description: "If the daemon should be started, requires `planner: linux`"
     required: false
+    default: true
   diagnostic-endpoint:
     description: "Diagnostic endpoint url where the installer sends data to. To disable set this to an empty string."
     default: "https://install.determinate.systems/nix/diagnostic"
@@ -99,236 +102,5 @@ inputs:
     default: "true"
 
 runs:
-  using: composite
+  using: "node16"
-  steps:
+  main: 'dist/index.js'
-    - name: Install Nix
-      shell: bash
-      run: |
-        if [ -f "/nix/receipt.json" ] && [ -f "/nix/nix-installer" ]; then
-          if ([ -n "${{ inputs.nix-installer-revision }}" ] || [ -n "${{ inputs.nix-installer-branch }}" ]) && [ "${{ inputs.reinstall }}" != "true" ]; then
-            echo "Detection of existing installation versions isn't supported when \`nix-installer-revision\` or \`nix-installer-branch\` are set, \`reinstall: true\` should also be set"
-          fi
-
-          if [ -n "${{ inputs.reinstall }}" ] && [ "${{ inputs.reinstall }}" == "true" ]; then
-            /nix/nix-installer uninstall --no-confirm
-          else
-            EXISTING_VERSION=$(/nix/nix-installer --version | awk '{ print $2 }')
-            if [ -n "${{ inputs.nix-installer-tag }}" ] && [ "${{ inputs.nix-installer-tag }}" != "$EXISTING_VERSION" ]; then
-              echo "`nix-installer` version mismatch, use `reinstall: true` to reinstall Nix using the new `nix-installer` version (consider backing up `/nix/store`)"
-              exit 1
-            fi
-            echo "Nix was already installed, using existing install"
-            echo "/nix/var/nix/profiles/default/bin" >> $GITHUB_PATH
-            echo "$HOME/.nix-profile/bin" >> $GITHUB_PATH
-            exit 0
-          fi
-        fi
-
-        NIX_EXTRA_CONF_FILE=$(mktemp)
-
-        if [ -n "$ACT" ] && [ ! -n "$NOT_ACT" ]; then
-          echo 'Detected `$ACT` environment, assuming this is a https://github.com/nektos/act created container, set `NOT_ACT=true` to override this. This will change the settings of the `init` as well as `extra-conf` to be compatible with `act`'
-          export NIX_INSTALLER_INIT="none"
-          echo "Set NIX_INSTALLER_INIT=$NIX_INSTALLER_INIT"
-          echo "sandbox = false" >> ${NIX_EXTRA_CONF_FILE}
-        fi
-
-        if [ -n "${{ inputs.modify-profile }}" ]; then
-          export NIX_INSTALLER_MODIFY_PROFILE=${{ inputs.modify-profile }}
-          echo "Set NIX_INSTALLER_MODIFY_PROFILE=$NIX_INSTALLER_MODIFY_PROFILE"
-        fi
-
-        if [ -n "${{ inputs.nix-build-user-count }}" ]; then
-          export NIX_INSTALLER_NIX_BUILD_USER_COUNT=${{ inputs.nix-build-user-count }}
-          echo "Set NIX_INSTALLER_NIX_BUILD_USER_COUNT=$NIX_INSTALLER_NIX_BUILD_USER_COUNT"
-        fi
-
-        if [ -n "${{ inputs.nix-build-group-name }}" ]; then
-          export NIX_INSTALLER_NIX_BUILD_GROUP_NAME=${{ inputs.nix-build-group-name }}
-          echo "Set NIX_INSTALLER_NIX_BUILD_GROUP_NAME=$NIX_INSTALLER_NIX_BUILD_GROUP_NAME"
-        fi
-
-        if [ -n "${{ inputs.nix-build-group-id }}" ]; then
-          export NIX_INSTALLER_NIX_BUILD_GROUP_ID=${{ inputs.nix-build-group-id }}
-          echo "Set NIX_INSTALLER_NIX_BUILD_GROUP_ID=$NIX_INSTALLER_NIX_BUILD_GROUP_ID"
-        fi
-
-        if [ -n "${{ inputs.nix-build-user-prefix }}" ]; then
-          export NIX_INSTALLER_NIX_BUILD_USER_PREFIX=${{ inputs.nix-build-user-prefix }}
-          echo "Set NIX_INSTALLER_NIX_BUILD_USER_PREFIX=$NIX_INSTALLER_NIX_BUILD_USER_PREFIX"
-        fi
-
-        if [ -n "${{ inputs.nix-build-user-base }}" ]; then
-          export NIX_INSTALLER_NIX_BUILD_USER_BASE=${{ inputs.nix-build-user-base }}
-          echo "Set NIX_INSTALLER_NIX_BUILD_USER_BASE=$NIX_INSTALLER_NIX_BUILD_USER_BASE"
-        fi
-
-        if [ -n "${{ inputs.nix-package-url }}" ]; then
-          export NIX_INSTALLER_NIX_PACKAGE_URL=${{ inputs.nix-package-url }}
-          echo "Set NIX_INSTALLER_NIX_PACKAGE_URL=$NIX_INSTALLER_NIX_PACKAGE_URL"
-        fi
-
-        if [ -n "${{ inputs.extra-conf }}" ]; then
-          echo "${{ inputs.extra-conf }}" >> ${NIX_EXTRA_CONF_FILE}
-        fi
-        if [ -n "${{ inputs.github-token }}" ]; then
-          echo "access-tokens = github.com=${{ inputs.github-token }}" >> ${NIX_EXTRA_CONF_FILE}
-        fi
-        if [ "${{ inputs.trust-runner-user }}" == "true" ]; then
-          echo "trusted-users = root $USER" >> ${NIX_EXTRA_CONF_FILE}
-        fi
-        if [ -n "$NIX_EXTRA_CONF_FILE" ]; then
-          export NIX_INSTALLER_EXTRA_CONF=$(cat ${NIX_EXTRA_CONF_FILE})
-          echo "Set NIX_INSTALLER_EXTRA_CONF=$NIX_INSTALLER_EXTRA_CONF"
-        fi
-
-        if [ -n "${{ inputs.mac-encrypt }}" ]; then
-          export NIX_INSTALLER_ENCRYPT=${{ inputs.mac-encrypt }}
-          echo "Set NIX_INSTALLER_ENCRYPT=$NIX_INSTALLER_ENCRYPT"
-        fi
-
-        if [ -n "${{ inputs.mac-case-sensitive }}" ]; then
-          export NIX_INSTALLER_CASE_SENSITIVE=${{ inputs.mac-case-sensitive }}
-          echo "Set NIX_INSTALLER_CASE_SENSITIVE=$NIX_INSTALLER_CASE_SENSITIVE"
-        fi
-
-        if [ -n "${{ inputs.mac-volume-label }}" ]; then
-          export NIX_INSTALLER_VOLUME_LABEL=${{ inputs.mac-volume-label }}
-          echo "Set NIX_INSTALLER_VOLUME_LABEL=$NIX_INSTALLER_VOLUME_LABEL"
-        fi
-
-        if [ -n "${{ inputs.mac-root-disk }}" ]; then
-          export NIX_INSTALLER_ROOT_DISK=${{ inputs.mac-root-disk }}
-          echo "Set NIX_INSTALLER_ROOT_DISK=$NIX_INSTALLER_ROOT_DISK"
-        fi
-
-        if [ -n "${{ inputs.nix-installer-pr }}" ] && [ -n "${{ inputs.nix-installer-tag }}" ]; then
-          echo "The nix-installer-pr and nix-installer-tag options conflict, please choose one"
-          exit 1
-        fi
-        if [ -n "${{ inputs.nix-installer-pr }}" ] && [ -n "${{ inputs.nix-installer-revision }}" ]; then
-          echo "The nix-installer-pr and nix-installer-revision options conflict, please choose one"
-          exit 1
-        fi
-        if [ -n "${{ inputs.nix-installer-pr }}" ] && [ -n "${{ inputs.nix-installer-branch }}" ]; then
-          echo "The nix-installer-pr and nix-installer-branch options conflict, please choose one"
-          exit 1
-        fi
-        if [ -n "${{ inputs.nix-installer-tag }}" ] && [ -n "${{ inputs.nix-installer-revision }}" ]; then
-          echo "The nix-installer-tag and nix-installer-revision options conflict, please choose one"
-          exit 1
-        fi
-        if [ -n "${{ inputs.nix-installer-branch }}" ] && [ -n "${{ inputs.nix-installer-revision }}" ]; then
-          echo "The nix-installer-branch and nix-installer-revision options conflict, please choose one"
-          exit 1
-        fi
-        if [ -n "${{ inputs.nix-installer-tag }}" ] && [ -n "${{ inputs.nix-installer-branch }}" ]; then
-          echo "The nix-installer-tag and nix-installer-branch options conflict, please choose one"
-          exit 1
-        fi
-        if [ -n "${{ inputs.nix-installer-url }}" ] && [ -n "${{ inputs.nix-installer-pr }}" ]; then
-          echo "The nix-installer-url and nix-installer-pr options conflict, please choose one"
-          exit 1
-        fi
-        if [ -n "${{ inputs.nix-installer-url }}" ] && [ -n "${{ inputs.nix-installer-tag }}" ]; then
-          echo "The nix-installer-url and nix-installer-tag options conflict, please choose one"
-          exit 1
-        fi
-        if [ -n "${{ inputs.nix-installer-url }}" ] && [ -n "${{ inputs.nix-installer-branch }}" ]; then
-          echo "The nix-installer-url and nix-installer-branch options conflict, please choose one"
-          exit 1
-        fi
-
-        if [ -n "${{ inputs.local-root }}" ]; then
-          if [ "$RUNNER_OS" == "macOS" ]; then
-            export PYTHON="python3"
-          else
-            export PYTHON="python"
-          fi
-          $PYTHON -m http.server --directory ${{ inputs.local-root }} --bind 0.0.0.0 8000 &
-          export HTTP_PID=$!
-          echo "Started simple http server for ${{ inputs.local-root }} on 0.0.0.0:8000"
-          while (! (: </dev/tcp/localhost/8000) &> /dev/null); do
-            sleep 1
-          done
-          export NIX_INSTALLER_FORCE_ALLOW_HTTP="1"
-          echo "Set NIX_INSTALLER_FORCE_ALLOW_HTTP=$NIX_INSTALLER_FORCE_ALLOW_HTTP"
-          export NIX_INSTALLER_URL=0.0.0.0:8000/nix-installer.sh
-          echo "Set NIX_INSTALLER_URL=$NIX_INSTALLER_URL"
-          export NIX_INSTALLER_BINARY_ROOT=http://0.0.0.0:8000/
-          echo "Set NIX_INSTALLER_BINARY_ROOT=$NIX_INSTALLER_BINARY_ROOT"
-          export NIX_INSTALLER_FORCE_ALLOW_HTTP=1
-          echo "Set NIX_INSTALLER_FORCE_ALLOW_HTTP=$NIX_INSTALLER_FORCE_ALLOW_HTTP"
-        else
-          if [ -n "${{ inputs.nix-installer-url }}" ]; then
-            export NIX_INSTALLER_URL="${{ inputs.nix-installer-url }}"
-          else
-            if [ -n "${{ inputs.nix-installer-pr }}" ]; then
-              export NIX_INSTALLER_URL="https://install.determinate.systems/nix/pr/${{ inputs.nix-installer-pr }}?ci=github"
-            elif [ -n "${{ inputs.nix-installer-tag }}" ]; then
-              export NIX_INSTALLER_URL="https://install.determinate.systems/nix/tag/${{ inputs.nix-installer-tag }}?ci=github"
-            elif [ -n "${{ inputs.nix-installer-revision }}" ]; then
-              export NIX_INSTALLER_URL="https://install.determinate.systems/nix/rev/${{ inputs.nix-installer-revision }}?ci=github"
-            elif [ -n "${{ inputs.nix-installer-branch }}" ]; then
-              export NIX_INSTALLER_URL="https://install.determinate.systems/nix/branch/${{ inputs.nix-installer-branch }}?ci=github"
-            else
-              export NIX_INSTALLER_URL="https://install.determinate.systems/nix?ci=github"
-            fi
-          fi
-          echo "Set NIX_INSTALLER_URL=$NIX_INSTALLER_URL"
-        fi
-
-        if [ -n "${{ inputs.logger }}" ]; then
-          export NIX_INSTALLER_LOGGER=${{ inputs.logger }}
-          echo "Set NIX_INSTALLER_LOGGER=$NIX_INSTALLER_LOGGER"
-        fi
-
-        if [ -n "${{ inputs.init }}" ]; then
-          export NIX_INSTALLER_INIT=${{ inputs.init }}
-          echo "Set NIX_INSTALLER_INIT=$NIX_INSTALLER_INIT"
-        fi
-
-        if [ -n "${{ inputs.start-daemon }}" ]; then
-          export NIX_INSTALLER_START_DAEMON=${{ inputs.start-daemon }}
-          echo "Set NIX_INSTALLER_START_DAEMON=$NIX_INSTALLER_START_DAEMON"
-        fi
-
-        if [ -n "${{ inputs.log-directives }}" ]; then
-          export NIX_INSTALLER_LOG_DIRECTIVES=${{ inputs.log-directives }}
-          echo "Set NIX_INSTALLER_LOG_DIRECTIVES=$NIX_INSTALLER_LOG_DIRECTIVES"
-        fi
-
-        if [ -n "${{ inputs.backtrace }}" ]; then
-          export RUST_BACKTRACE=${{ inputs.backtrace }}
-          echo "Set RUST_BACKTRACE=$RUST_BACKTRACE"
-        fi
-
-        if [ -n "${{ inputs.diagnostic-endpoint }}" ]; then
-          export NIX_INSTALLER_DIAGNOSTIC_ENDPOINT="${{ inputs.diagnostic-endpoint }}"
-          echo "Set NIX_INSTALLER_DIAGNOSTIC_ENDPOINT=$NIX_INSTALLER_DIAGNOSTIC_ENDPOINT"
-        fi
-
-        export NIX_INSTALLER_NO_CONFIRM=true
-        echo "Set NIX_INSTALLER_NO_CONFIRM=$NIX_INSTALLER_NO_CONFIRM"
-
-        if [ -n "${{ inputs.planner }}" ]; then
-          export PLANNER="${{ inputs.planner }}"
-          echo "Set PLANNER=$PLANNER"
-        else
-          if [ "${RUNNER_OS}" == "Linux" ]; then
-            export PLANNER="linux"
-            echo "Set PLANNER=$PLANNER (Default)"
-          elif [ "${RUNNER_OS}" == "macOS" ]; then
-            export PLANNER="macos"
-            echo "Set PLANNER=$PLANNER (Default)"
-          else
-            echo "${RUNNER_OS} not supported"
-            exit 1
-          fi
-        fi
-
-        curl --retry 20 -L $NIX_INSTALLER_URL | sh -s -- install ${PLANNER} ${{ inputs.extra-args }}
-
-        if [ -n "$HTTP_PID" ]; then
-          kill $HTTP_PID
-        fi

dist/37.index.js

@@ -0,0 +1,453 @@
+"use strict";
+exports.id = 37;
+exports.ids = [37];
+exports.modules = {
+
+/***/ 4037:
+/***/ ((__unused_webpack___webpack_module__, __webpack_exports__, __webpack_require__) => {
+
+__webpack_require__.r(__webpack_exports__);
+/* harmony export */ __webpack_require__.d(__webpack_exports__, {
+/* harmony export */   "toFormData": () => (/* binding */ toFormData)
+/* harmony export */ });
+/* harmony import */ var fetch_blob_from_js__WEBPACK_IMPORTED_MODULE_0__ = __webpack_require__(2185);
+/* harmony import */ var formdata_polyfill_esm_min_js__WEBPACK_IMPORTED_MODULE_1__ = __webpack_require__(8010);
+
+
+
+let s = 0;
+const S = {
+	START_BOUNDARY: s++,
+	HEADER_FIELD_START: s++,
+	HEADER_FIELD: s++,
+	HEADER_VALUE_START: s++,
+	HEADER_VALUE: s++,
+	HEADER_VALUE_ALMOST_DONE: s++,
+	HEADERS_ALMOST_DONE: s++,
+	PART_DATA_START: s++,
+	PART_DATA: s++,
+	END: s++
+};
+
+let f = 1;
+const F = {
+	PART_BOUNDARY: f,
+	LAST_BOUNDARY: f *= 2
+};
+
+const LF = 10;
+const CR = 13;
+const SPACE = 32;
+const HYPHEN = 45;
+const COLON = 58;
+const A = 97;
+const Z = 122;
+
+const lower = c => c | 0x20;
+
+const noop = () => {};
+
+class MultipartParser {
+	/**
+	 * @param {string} boundary
+	 */
+	constructor(boundary) {
+		this.index = 0;
+		this.flags = 0;
+
+		this.onHeaderEnd = noop;
+		this.onHeaderField = noop;
+		this.onHeadersEnd = noop;
+		this.onHeaderValue = noop;
+		this.onPartBegin = noop;
+		this.onPartData = noop;
+		this.onPartEnd = noop;
+
+		this.boundaryChars = {};
+
+		boundary = '\r\n--' + boundary;
+		const ui8a = new Uint8Array(boundary.length);
+		for (let i = 0; i < boundary.length; i++) {
+			ui8a[i] = boundary.charCodeAt(i);
+			this.boundaryChars[ui8a[i]] = true;
+		}
+
+		this.boundary = ui8a;
+		this.lookbehind = new Uint8Array(this.boundary.length + 8);
+		this.state = S.START_BOUNDARY;
+	}
+
+	/**
+	 * @param {Uint8Array} data
+	 */
+	write(data) {
+		let i = 0;
+		const length_ = data.length;
+		let previousIndex = this.index;
+		let {lookbehind, boundary, boundaryChars, index, state, flags} = this;
+		const boundaryLength = this.boundary.length;
+		const boundaryEnd = boundaryLength - 1;
+		const bufferLength = data.length;
+		let c;
+		let cl;
+
+		const mark = name => {
+			this[name + 'Mark'] = i;
+		};
+
+		const clear = name => {
+			delete this[name + 'Mark'];
+		};
+
+		const callback = (callbackSymbol, start, end, ui8a) => {
+			if (start === undefined || start !== end) {
+				this[callbackSymbol](ui8a && ui8a.subarray(start, end));
+			}
+		};
+
+		const dataCallback = (name, clear) => {
+			const markSymbol = name + 'Mark';
+			if (!(markSymbol in this)) {
+				return;
+			}
+
+			if (clear) {
+				callback(name, this[markSymbol], i, data);
+				delete this[markSymbol];
+			} else {
+				callback(name, this[markSymbol], data.length, data);
+				this[markSymbol] = 0;
+			}
+		};
+
+		for (i = 0; i < length_; i++) {
+			c = data[i];
+
+			switch (state) {
+				case S.START_BOUNDARY:
+					if (index === boundary.length - 2) {
+						if (c === HYPHEN) {
+							flags |= F.LAST_BOUNDARY;
+						} else if (c !== CR) {
+							return;
+						}
+
+						index++;
+						break;
+					} else if (index - 1 === boundary.length - 2) {
+						if (flags & F.LAST_BOUNDARY && c === HYPHEN) {
+							state = S.END;
+							flags = 0;
+						} else if (!(flags & F.LAST_BOUNDARY) && c === LF) {
+							index = 0;
+							callback('onPartBegin');
+							state = S.HEADER_FIELD_START;
+						} else {
+							return;
+						}
+
+						break;
+					}
+
+					if (c !== boundary[index + 2]) {
+						index = -2;
+					}
+
+					if (c === boundary[index + 2]) {
+						index++;
+					}
+
+					break;
+				case S.HEADER_FIELD_START:
+					state = S.HEADER_FIELD;
+					mark('onHeaderField');
+					index = 0;
+					// falls through
+				case S.HEADER_FIELD:
+					if (c === CR) {
+						clear('onHeaderField');
+						state = S.HEADERS_ALMOST_DONE;
+						break;
+					}
+
+					index++;
+					if (c === HYPHEN) {
+						break;
+					}
+
+					if (c === COLON) {
+						if (index === 1) {
+							// empty header field
+							return;
+						}
+
+						dataCallback('onHeaderField', true);
+						state = S.HEADER_VALUE_START;
+						break;
+					}
+
+					cl = lower(c);
+					if (cl < A || cl > Z) {
+						return;
+					}
+
+					break;
+				case S.HEADER_VALUE_START:
+					if (c === SPACE) {
+						break;
+					}
+
+					mark('onHeaderValue');
+					state = S.HEADER_VALUE;
+					// falls through
+				case S.HEADER_VALUE:
+					if (c === CR) {
+						dataCallback('onHeaderValue', true);
+						callback('onHeaderEnd');
+						state = S.HEADER_VALUE_ALMOST_DONE;
+					}
+
+					break;
+				case S.HEADER_VALUE_ALMOST_DONE:
+					if (c !== LF) {
+						return;
+					}
+
+					state = S.HEADER_FIELD_START;
+					break;
+				case S.HEADERS_ALMOST_DONE:
+					if (c !== LF) {
+						return;
+					}
+
+					callback('onHeadersEnd');
+					state = S.PART_DATA_START;
+					break;
+				case S.PART_DATA_START:
+					state = S.PART_DATA;
+					mark('onPartData');
+					// falls through
+				case S.PART_DATA:
+					previousIndex = index;
+
+					if (index === 0) {
+						// boyer-moore derrived algorithm to safely skip non-boundary data
+						i += boundaryEnd;
+						while (i < bufferLength && !(data[i] in boundaryChars)) {
+							i += boundaryLength;
+						}
+
+						i -= boundaryEnd;
+						c = data[i];
+					}
+
+					if (index < boundary.length) {
+						if (boundary[index] === c) {
+							if (index === 0) {
+								dataCallback('onPartData', true);
+							}
+
+							index++;
+						} else {
+							index = 0;
+						}
+					} else if (index === boundary.length) {
+						index++;
+						if (c === CR) {
+							// CR = part boundary
+							flags |= F.PART_BOUNDARY;
+						} else if (c === HYPHEN) {
+							// HYPHEN = end boundary
+							flags |= F.LAST_BOUNDARY;
+						} else {
+							index = 0;
+						}
+					} else if (index - 1 === boundary.length) {
+						if (flags & F.PART_BOUNDARY) {
+							index = 0;
+							if (c === LF) {
+								// unset the PART_BOUNDARY flag
+								flags &= ~F.PART_BOUNDARY;
+								callback('onPartEnd');
+								callback('onPartBegin');
+								state = S.HEADER_FIELD_START;
+								break;
+							}
+						} else if (flags & F.LAST_BOUNDARY) {
+							if (c === HYPHEN) {
+								callback('onPartEnd');
+								state = S.END;
+								flags = 0;
+							} else {
+								index = 0;
+							}
+						} else {
+							index = 0;
+						}
+					}
+
+					if (index > 0) {
+						// when matching a possible boundary, keep a lookbehind reference
+						// in case it turns out to be a false lead
+						lookbehind[index - 1] = c;
+					} else if (previousIndex > 0) {
+						// if our boundary turned out to be rubbish, the captured lookbehind
+						// belongs to partData
+						const _lookbehind = new Uint8Array(lookbehind.buffer, lookbehind.byteOffset, lookbehind.byteLength);
+						callback('onPartData', 0, previousIndex, _lookbehind);
+						previousIndex = 0;
+						mark('onPartData');
+
+						// reconsider the current character even so it interrupted the sequence
+						// it could be the beginning of a new sequence
+						i--;
+					}
+
+					break;
+				case S.END:
+					break;
+				default:
+					throw new Error(`Unexpected state entered: ${state}`);
+			}
+		}
+
+		dataCallback('onHeaderField');
+		dataCallback('onHeaderValue');
+		dataCallback('onPartData');
+
+		// Update properties for the next call
+		this.index = index;
+		this.state = state;
+		this.flags = flags;
+	}
+
+	end() {
+		if ((this.state === S.HEADER_FIELD_START && this.index === 0) ||
+			(this.state === S.PART_DATA && this.index === this.boundary.length)) {
+			this.onPartEnd();
+		} else if (this.state !== S.END) {
+			throw new Error('MultipartParser.end(): stream ended unexpectedly');
+		}
+	}
+}
+
+function _fileName(headerValue) {
+	// matches either a quoted-string or a token (RFC 2616 section 19.5.1)
+	const m = headerValue.match(/\bfilename=("(.*?)"|([^()<>@,;:\\"/[\]?={}\s\t]+))($|;\s)/i);
+	if (!m) {
+		return;
+	}
+
+	const match = m[2] || m[3] || '';
+	let filename = match.slice(match.lastIndexOf('\\') + 1);
+	filename = filename.replace(/%22/g, '"');
+	filename = filename.replace(/&#(\d{4});/g, (m, code) => {
+		return String.fromCharCode(code);
+	});
+	return filename;
+}
+
+async function toFormData(Body, ct) {
+	if (!/multipart/i.test(ct)) {
+		throw new TypeError('Failed to fetch');
+	}
+
+	const m = ct.match(/boundary=(?:"([^"]+)"|([^;]+))/i);
+
+	if (!m) {
+		throw new TypeError('no or bad content-type header, no multipart boundary');
+	}
+
+	const parser = new MultipartParser(m[1] || m[2]);
+
+	let headerField;
+	let headerValue;
+	let entryValue;
+	let entryName;
+	let contentType;
+	let filename;
+	const entryChunks = [];
+	const formData = new formdata_polyfill_esm_min_js__WEBPACK_IMPORTED_MODULE_1__/* .FormData */ .Ct();
+
+	const onPartData = ui8a => {
+		entryValue += decoder.decode(ui8a, {stream: true});
+	};
+
+	const appendToFile = ui8a => {
+		entryChunks.push(ui8a);
+	};
+
+	const appendFileToFormData = () => {
+		const file = new fetch_blob_from_js__WEBPACK_IMPORTED_MODULE_0__/* .File */ .$B(entryChunks, filename, {type: contentType});
+		formData.append(entryName, file);
+	};
+
+	const appendEntryToFormData = () => {
+		formData.append(entryName, entryValue);
+	};
+
+	const decoder = new TextDecoder('utf-8');
+	decoder.decode();
+
+	parser.onPartBegin = function () {
+		parser.onPartData = onPartData;
+		parser.onPartEnd = appendEntryToFormData;
+
+		headerField = '';
+		headerValue = '';
+		entryValue = '';
+		entryName = '';
+		contentType = '';
+		filename = null;
+		entryChunks.length = 0;
+	};
+
+	parser.onHeaderField = function (ui8a) {
+		headerField += decoder.decode(ui8a, {stream: true});
+	};
+
+	parser.onHeaderValue = function (ui8a) {
+		headerValue += decoder.decode(ui8a, {stream: true});
+	};
+
+	parser.onHeaderEnd = function () {
+		headerValue += decoder.decode();
+		headerField = headerField.toLowerCase();
+
+		if (headerField === 'content-disposition') {
+			// matches either a quoted-string or a token (RFC 2616 section 19.5.1)
+			const m = headerValue.match(/\bname=("([^"]*)"|([^()<>@,;:\\"/[\]?={}\s\t]+))/i);
+
+			if (m) {
+				entryName = m[2] || m[3] || '';
+			}
+
+			filename = _fileName(headerValue);
+
+			if (filename) {
+				parser.onPartData = appendToFile;
+				parser.onPartEnd = appendFileToFormData;
+			}
+		} else if (headerField === 'content-type') {
+			contentType = headerValue;
+		}
+
+		headerValue = '';
+		headerField = '';
+	};
+
+	for await (const chunk of Body) {
+		parser.write(chunk);
+	}
+
+	parser.end();
+
+	return formData;
+}
+
+
+/***/ })
+
+};
+;
+//# sourceMappingURL=37.index.js.map

dist/licenses.txt

@@ -0,0 +1,23 @@
+node-fetch
+MIT
+The MIT License (MIT)
+
+Copyright (c) 2016 - 2020 Node Fetch Team
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

package.json

@@ -0,0 +1,41 @@
+{
+  "name": "nix-installer-action",
+  "version": "1.0.0",
+  "description": "You can use [`nix-installer`](https://github.com/DeterminateSystems/nix-installer) as a Github action:",
+  "main": "lib/main.js",
+  "scripts": {
+    "build": "tsc",
+    "format": "prettier --write '**/*.ts'",
+    "lint": "eslint src/**/*.ts",
+    "package": "ncc build --source-map --license licenses.txt",
+    "all": "npm run build && npm run format && npm run lint && npm run package"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/DeterminateSystems/nix-installer-action.git"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "bugs": {
+    "url": "https://github.com/DeterminateSystems/nix-installer-action/issues"
+  },
+  "homepage": "https://github.com/DeterminateSystems/nix-installer-action#readme",
+  "dependencies": {
+    "@actions/core": "^1.10.0",
+    "@actions/github": "^5.1.1",
+    "node-fetch": "^3.3.1",
+    "string-argv": "^0.3.2"
+  },
+  "devDependencies": {
+    "@types/node": "^18.16.3",
+    "@typescript-eslint/parser": "^5.59.2",
+    "@vercel/ncc": "^0.36.1",
+    "eslint": "^8.44.0",
+    "eslint-plugin-github": "^4.3.6",
+    "eslint-plugin-import": "^2.26.0",
+    "eslint-plugin-prettier": "^5.0.0-alpha.1",
+    "prettier": "^3.0.0",
+    "typescript": "^5.1.6"
+  }
+}

src/main.ts

@@ -0,0 +1,552 @@
+import * as actions_core from "@actions/core";
+import { mkdtemp, chmod, access } from "node:fs/promises";
+import { spawn } from "node:child_process";
+import { join } from "node:path";
+import { tmpdir } from "node:os";
+import { pipeline } from "node:stream";
+import fetch from "node-fetch";
+import { promisify } from "node:util";
+import fs from "node:fs";
+import stringArgv from "string-argv";
+
+class NixInstallerAction {
+  platform: string;
+  nix_package_url: string | null;
+  backtrace: string | null;
+  extra_args: string | null;
+  extra_conf: string[] | null;
+  github_token: string | null;
+  // TODO: linux_init
+  init: string | null;
+  local_root: string | null;
+  log_directives: string | null;
+  logger: string | null;
+  ssl_cert_file: string | null;
+  proxy: string | null;
+  mac_case_sensitive: string | null;
+  mac_encrypt: string | null;
+  mac_root_disk: string | null;
+  mac_volume_label: string | null;
+  modify_profile: boolean;
+  nix_build_group_id: number | null;
+  nix_build_group_name: string | null;
+  nix_build_user_base: number | null;
+  nix_build_user_count: number | null;
+  nix_build_user_prefix: string | null;
+  planner: string | null;
+  reinstall: boolean;
+  start_daemon: boolean;
+  diagnostic_endpoint: string | null;
+  trust_runner_user: boolean | null;
+  nix_installer_url: URL;
+
+  constructor() {
+    this.platform = get_nix_platform();
+    this.nix_package_url = action_input_string_or_null("nix-package-url");
+    this.backtrace = action_input_string_or_null("backtrace");
+    this.extra_args = action_input_string_or_null("extra-args");
+    this.extra_conf = action_input_multiline_string_or_null("extra-conf");
+    this.github_token = action_input_string_or_null("github-token");
+    this.init = action_input_string_or_null("init");
+    this.local_root = action_input_string_or_null("local-root");
+    this.log_directives = action_input_string_or_null("log-directives");
+    this.logger = action_input_string_or_null("logger");
+    this.ssl_cert_file = action_input_string_or_null("ssl-cert-file");
+    this.proxy = action_input_string_or_null("proxy");
+    this.mac_case_sensitive = action_input_string_or_null("mac-case-sensitive");
+    this.mac_encrypt = action_input_string_or_null("mac-encrypt");
+    this.mac_root_disk = action_input_string_or_null("mac-root-disk");
+    this.mac_volume_label = action_input_string_or_null("mac-volume-label");
+    this.modify_profile = action_input_bool("modify-profile");
+    this.nix_build_group_id = action_input_number_or_null("nix-build-group-id");
+    this.nix_build_group_name = action_input_string_or_null(
+      "nix-build-group-name",
+    );
+    this.nix_build_user_base = action_input_number_or_null(
+      "nix_build-user-base",
+    );
+    this.nix_build_user_count = action_input_number_or_null(
+      "nix-build-user-count",
+    );
+    this.nix_build_user_prefix = action_input_string_or_null(
+      "nix-build-user-prefix",
+    );
+    this.planner = action_input_string_or_null("planner");
+    this.reinstall = action_input_bool("reinstall");
+    this.start_daemon = action_input_bool("start-daemon");
+    this.diagnostic_endpoint = action_input_string_or_null(
+      "diagnostic-endpoint",
+    );
+    this.trust_runner_user = action_input_bool("trust-runner-user");
+    this.nix_installer_url = resolve_nix_installer_url(this.platform);
+  }
+
+  private executionEnvironment(): ExecuteEnvironment {
+    const execution_env: ExecuteEnvironment = {};
+
+    execution_env.NIX_INSTALLER_NO_CONFIRM = "true";
+
+    if (this.backtrace !== null) {
+      execution_env.RUST_BACKTRACE = this.backtrace;
+    }
+    if (this.modify_profile !== null) {
+      if (this.modify_profile) {
+        execution_env.NIX_INSTALLER_MODIFY_PROFILE = "true";
+      } else {
+        execution_env.NIX_INSTALLER_MODIFY_PROFILE = "false";
+      }
+    }
+
+    if (this.nix_build_group_id !== null) {
+      execution_env.NIX_INSTALLER_NIX_BUILD_GROUP_ID = `${this.nix_build_group_id}`;
+    }
+
+    if (this.nix_build_group_name !== null) {
+      execution_env.NIX_INSTALLER_NIX_BUILD_GROUP_NAME =
+        this.nix_build_group_name;
+    }
+
+    if (this.nix_build_user_prefix !== null) {
+      execution_env.NIX_INSTALLER_NIX_BUILD_USER_PREFIX =
+        this.nix_build_user_prefix;
+    }
+
+    if (this.nix_build_user_count !== null) {
+      execution_env.NIX_INSTALLER_NIX_BUILD_USER_COUNT = `${this.nix_build_user_count}`;
+    }
+
+    if (this.nix_build_user_base !== null) {
+      execution_env.NIX_INSTALLER_NIX_BUILD_USER_ID_BASE = `${this.nix_build_user_count}`;
+    }
+
+    if (this.nix_package_url !== null) {
+      execution_env.NIX_INSTALLER_NIX_PACKAGE_URL = `${this.nix_package_url}`;
+    }
+
+    if (this.proxy !== null) {
+      execution_env.NIX_INSTALLER_PROXY = this.proxy;
+    }
+
+    if (this.ssl_cert_file !== null) {
+      execution_env.NIX_INSTALLER_SSL_CERT_FILE = this.ssl_cert_file;
+    }
+
+    if (this.diagnostic_endpoint !== null) {
+      execution_env.NIX_INSTALLER_DIAGNOSTIC_ENDPOINT =
+        this.diagnostic_endpoint;
+    }
+
+    // TODO: Error if the user uses these on not-MacOS
+    if (this.mac_encrypt !== null) {
+      if (process.env.RUNNER_OS !== "macOS") {
+        throw new Error("`mac-encrypt` while `$RUNNER_OS` was not `macOS`");
+      }
+      execution_env.NIX_INSTALLER_ENCRYPT = this.mac_encrypt;
+    }
+
+    if (this.mac_case_sensitive !== null) {
+      if (process.env.RUNNER_OS !== "macOS") {
+        throw new Error(
+          "`mac-case-sensitive` while `$RUNNER_OS` was not `macOS`",
+        );
+      }
+      execution_env.NIX_INSTALLER_CASE_SENSITIVE = this.mac_case_sensitive;
+    }
+
+    if (this.mac_volume_label !== null) {
+      if (process.env.RUNNER_OS !== "macOS") {
+        throw new Error(
+          "`mac-volume-label` while `$RUNNER_OS` was not `macOS`",
+        );
+      }
+      execution_env.NIX_INSTALLER_VOLUME_LABEL = this.mac_volume_label;
+    }
+
+    if (this.mac_root_disk !== null) {
+      if (process.env.RUNNER_OS !== "macOS") {
+        throw new Error("`mac-root-disk` while `$RUNNER_OS` was not `macOS`");
+      }
+      execution_env.NIX_INSTALLER_ROOT_DISK = this.mac_root_disk;
+    }
+
+    if (this.logger !== null) {
+      execution_env.NIX_INSTALLER_LOGGER = this.logger;
+    }
+
+    if (this.log_directives !== null) {
+      execution_env.NIX_INSTALLER_LOG_DIRECTIVES = this.log_directives;
+    }
+
+    // TODO: Error if the user uses these on MacOS
+    if (this.init !== null) {
+      if (process.env.RUNNER_OS === "macOS") {
+        throw new Error(
+          "`init` is not a valid option when `$RUNNER_OS` is `macOS`",
+        );
+      }
+      execution_env.NIX_INSTALLER_INIT = this.init;
+    }
+
+    if (this.start_daemon !== null) {
+      if (this.start_daemon) {
+        execution_env.NIX_INSTALLER_START_DAEMON = "true";
+      } else {
+        execution_env.NIX_INSTALLER_START_DAEMON = "false";
+      }
+    }
+
+    let extra_conf = "";
+    if (this.github_token !== null) {
+      extra_conf += `access-tokens = github.com=${this.github_token}`;
+      extra_conf += "\n";
+    }
+    if (this.trust_runner_user !== null) {
+      extra_conf += `trusted-users = root ${process.env.USER}`;
+      extra_conf += "\n";
+    }
+    if (this.extra_conf !== null && this.extra_conf.length !== 0) {
+      extra_conf += this.extra_conf.join("\n");
+      extra_conf += "\n";
+    }
+    execution_env.NIX_INSTALLER_EXTRA_CONF = extra_conf;
+
+    if (process.env.ACT && !process.env.NOT_ACT) {
+      actions_core.info(
+        "Detected `$ACT` environment, assuming this is a https://github.com/nektos/act created container, set `NOT_ACT=true` to override this. This will change the setting of the `init` to be compatible with `act`",
+      );
+      execution_env.NIX_INSTALLER_INIT = "none";
+    }
+
+    return execution_env;
+  }
+
+  private async execute_install(binary_path: string): Promise<number> {
+    const execution_env = this.executionEnvironment();
+    actions_core.info(
+      `Execution environment: ${JSON.stringify(execution_env, null, 4)}`,
+    );
+
+    const args = ["install"];
+    if (this.planner) {
+      args.push(this.planner);
+    } else {
+      args.push(get_default_planner());
+    }
+
+    if (this.extra_args) {
+      const extra_args = stringArgv(this.extra_args);
+      args.concat(extra_args);
+    }
+
+    const merged_env = {
+      ...process.env, // To get $PATH, etc
+      ...execution_env,
+    };
+
+    const spawned = spawn(`${binary_path}`, args, {
+      env: merged_env,
+    });
+
+    spawned.stdout.setEncoding("utf-8");
+    spawned.stdout.on("data", (data) => {
+      const trimmed = data.trimEnd();
+      if (trimmed.length >= 0) {
+        actions_core.info(trimmed);
+      }
+    });
+
+    spawned.stderr.setEncoding("utf-8");
+    spawned.stderr.on("data", (data) => {
+      const trimmed = data.trimEnd();
+      if (trimmed.length >= 0) {
+        actions_core.info(trimmed);
+      }
+    });
+
+    const exit_code: number = await new Promise((resolve, _reject) => {
+      spawned.on("close", resolve);
+    });
+
+    if (exit_code !== 0) {
+      throw new Error(`Non-zero exit code of \`${exit_code}\` detected`);
+    }
+
+    return exit_code;
+  }
+
+  async install(): Promise<void> {
+    const existing_install = await this.detect_existing();
+    if (existing_install) {
+      if (this.reinstall) {
+        // We need to uninstall, then reinstall
+        actions_core.info(
+          "Nix was already installed, `reinstall` is set, uninstalling for a reinstall",
+        );
+        await this.execute_uninstall();
+      } else {
+        // We're already installed, and not reinstalling, just set GITHUB_PATH and finish early
+        await this.set_github_path();
+        actions_core.info("Nix was already installed, using existing install");
+        return;
+      }
+    }
+    // Normal just doing of the install
+    const binary_path = await this.fetch_binary();
+    await this.execute_install(binary_path);
+    await this.set_github_path();
+  }
+
+  async set_github_path(): Promise<void> {
+    // Interim versions of the `nix-installer` crate may have already manipulated `$GITHUB_PATH`, as root even! Accessing that will be an error.
+    try {
+      const nix_var_nix_profile_path = "/nix/var/nix/profiles/default/bin";
+      const home_nix_profile_path = `${process.env.HOME}/.nix-profile/bin`;
+      actions_core.addPath(nix_var_nix_profile_path);
+      actions_core.addPath(home_nix_profile_path);
+      actions_core.info(
+        `Added \`${nix_var_nix_profile_path}\` and \`${home_nix_profile_path}\` to \`$GITHUB_PATH\``,
+      );
+    } catch (error) {
+      actions_core.info(
+        "Skipping setting $GITHUB_PATH in action, the `nix-installer` crate seems to have done this already. From `nix-installer` version 0.11.0 and up, this step is done in the action. Prior to 0.11.0, this was only done in the `nix-installer` binary.",
+      );
+    }
+  }
+
+  async execute_uninstall(): Promise<number> {
+    const spawned = spawn(`/nix/nix-installer`, ["uninstall"], {
+      env: {
+        NIX_INSTALLER_NO_CONFIRM: "true",
+        ...process.env, // To get $PATH, etc
+      },
+    });
+
+    spawned.stdout.setEncoding("utf-8");
+    spawned.stdout.on("data", (data) => {
+      const trimmed = data.trimEnd();
+      if (trimmed.length >= 0) {
+        actions_core.info(trimmed);
+      }
+    });
+
+    spawned.stderr.setEncoding("utf-8");
+    spawned.stderr.on("data", (data) => {
+      const trimmed = data.trimEnd();
+      if (trimmed.length >= 0) {
+        actions_core.info(trimmed);
+      }
+    });
+
+    const exit_code: number = await new Promise((resolve, _reject) => {
+      spawned.on("close", resolve);
+    });
+
+    if (exit_code !== 0) {
+      throw new Error(`Non-zero exit code of \`${exit_code}\` detected`);
+    }
+
+    return exit_code;
+  }
+
+  async detect_existing(): Promise<boolean> {
+    const receipt_path = "/nix/receipt.json";
+    try {
+      await access(receipt_path);
+      // There is a /nix/receipt.json
+      return true;
+    } catch {
+      // No /nix/receipt.json
+      return false;
+    }
+  }
+
+  private async fetch_binary(): Promise<string> {
+    if (!this.local_root) {
+      actions_core.info(`Fetching binary from ${this.nix_installer_url}`);
+      const response = await fetch(this.nix_installer_url);
+      if (!response.ok) {
+        throw new Error(
+          `Got a status of ${response.status} from \`${this.nix_installer_url}\`, expected a 200`,
+        );
+      }
+
+      const tempdir = await mkdtemp(join(tmpdir(), "nix-installer-"));
+      const tempfile = join(tempdir, `nix-installer-${this.platform}`);
+
+      if (!response.ok) {
+        throw new Error(`unexpected response ${response.statusText}`);
+      }
+
+      if (response.body !== null) {
+        const streamPipeline = promisify(pipeline);
+        await streamPipeline(response.body, fs.createWriteStream(tempfile));
+        actions_core.info(`Downloaded \`nix-installer\` to \`${tempfile}\``);
+      } else {
+        throw new Error("No response body recieved");
+      }
+
+      // Make executable
+      await chmod(tempfile, fs.constants.S_IXUSR | fs.constants.S_IXGRP);
+
+      return tempfile;
+    } else {
+      const local_path = join(
+        this.local_root,
+        `nix-installer-${this.platform}`,
+      );
+      actions_core.info(`Using binary ${local_path}`);
+      return local_path;
+    }
+  }
+}
+
+type ExecuteEnvironment = {
+  // All env vars are strings, no fanciness here.
+  RUST_BACKTRACE?: string;
+  NIX_INSTALLER_MODIFY_PROFILE?: string;
+  NIX_INSTALLER_NIX_BUILD_GROUP_NAME?: string;
+  NIX_INSTALLER_NIX_BUILD_GROUP_ID?: string;
+  NIX_INSTALLER_NIX_BUILD_USER_PREFIX?: string;
+  NIX_INSTALLER_NIX_BUILD_USER_COUNT?: string;
+  NIX_INSTALLER_NIX_BUILD_USER_ID_BASE?: string;
+  NIX_INSTALLER_NIX_PACKAGE_URL?: string;
+  NIX_INSTALLER_PROXY?: string;
+  NIX_INSTALLER_SSL_CERT_FILE?: string;
+  NIX_INSTALLER_DIAGNOSTIC_ENDPOINT?: string;
+  NIX_INSTALLER_ENCRYPT?: string;
+  NIX_INSTALLER_CASE_SENSITIVE?: string;
+  NIX_INSTALLER_VOLUME_LABEL?: string;
+  NIX_INSTALLER_ROOT_DISK?: string;
+  NIX_INSTALLER_INIT?: string;
+  NIX_INSTALLER_START_DAEMON?: string;
+  NIX_INSTALLER_NO_CONFIRM?: string;
+  NIX_INSTALLER_EXTRA_CONF?: string;
+  NIX_INSTALLER_LOG_DIRECTIVES?: string;
+  NIX_INSTALLER_LOGGER?: string;
+};
+
+function get_nix_platform(): string {
+  const env_os = process.env.RUNNER_OS;
+  const env_arch = process.env.RUNNER_ARCH;
+
+  if (env_os === "macOS" && env_arch === "X64") {
+    return "x86_64-darwin";
+  } else if (env_os === "macOS" && env_arch === "ARM64") {
+    return "aarch64-darwin";
+  } else if (env_os === "Linux" && env_arch === "X64") {
+    return "x86_64-linux";
+  } else if (env_os === "Linux" && env_arch === "ARM64") {
+    return "aarch64-linux";
+  } else {
+    throw new Error(
+      `Unsupported \`RUNNER_OS\` (currently \`${env_os}\`) and \`RUNNER_ARCH\` (currently \`${env_arch}\`)  combination`,
+    );
+  }
+}
+
+function get_default_planner(): string {
+  const env_os = process.env.RUNNER_OS;
+
+  if (env_os === "macOS") {
+    return "macos";
+  } else if (env_os === "Linux") {
+    return "linux";
+  } else {
+    throw new Error(`Unsupported \`RUNNER_OS\` (currently \`${env_os}\`)`);
+  }
+}
+
+function resolve_nix_installer_url(platform: string): URL {
+  // Only one of these are allowed.
+  const nix_installer_branch = action_input_string_or_null(
+    "nix-installer-branch",
+  );
+  const nix_installer_pr = action_input_number_or_null("nix-installer-pr");
+  const nix_installer_revision = action_input_string_or_null(
+    "nix-installer-revision",
+  );
+  const nix_installer_tag = action_input_string_or_null("nix-installer-tag");
+  const nix_installer_url = action_input_string_or_null("nix-installer-url");
+
+  let resolved_nix_installer_url = null;
+  let num_set = 0;
+
+  if (nix_installer_branch !== null) {
+    num_set += 1;
+    resolved_nix_installer_url = new URL(
+      `https://install.determinate.systems/nix/branch/${nix_installer_branch}/nix-installer-${platform}?ci=github`,
+    );
+  } else if (nix_installer_pr !== null) {
+    num_set += 1;
+    resolved_nix_installer_url = new URL(
+      `https://install.determinate.systems/nix/pr/${nix_installer_pr}/nix-installer-${platform}?ci=github`,
+    );
+  } else if (nix_installer_revision !== null) {
+    num_set += 1;
+    resolved_nix_installer_url = new URL(
+      `https://install.determinate.systems/nix/rev/${nix_installer_revision}/nix-installer-${platform}?ci=github`,
+    );
+  } else if (nix_installer_tag !== null) {
+    num_set += 1;
+    resolved_nix_installer_url = new URL(
+      `https://install.determinate.systems/nix/tag/${nix_installer_tag}/nix-installer-${platform}?ci=github`,
+    );
+  } else if (nix_installer_url !== null) {
+    num_set += 1;
+    resolved_nix_installer_url = new URL(nix_installer_url);
+  } else {
+    resolved_nix_installer_url = new URL(
+      `https://install.determinate.systems/nix/nix-installer-${platform}?ci=github`,
+    );
+  }
+
+  if (num_set > 1) {
+    throw new Error(
+      `The following options are mututally exclusive, but ${num_set} were set: \`nix_installer_branch\`, \`nix_installer_pr\`, \`nix_installer_revision\`, \`nix_installer_tag\`, and \`nix_installer_url\``,
+    );
+  }
+  return resolved_nix_installer_url;
+}
+
+function action_input_string_or_null(name: string): string | null {
+  const value = actions_core.getInput(name);
+  if (value === "") {
+    return null;
+  } else {
+    return value;
+  }
+}
+
+function action_input_multiline_string_or_null(name: string): string[] | null {
+  const value = actions_core.getMultilineInput(name);
+  if (value.length === 0) {
+    return null;
+  } else {
+    return value;
+  }
+}
+
+function action_input_number_or_null(name: string): number | null {
+  const value = actions_core.getInput(name);
+  if (value === "") {
+    return null;
+  } else {
+    return Number(value);
+  }
+}
+
+function action_input_bool(name: string): boolean {
+  return actions_core.getBooleanInput(name);
+}
+
+async function main(): Promise<void> {
+  try {
+    const installer = new NixInstallerAction();
+
+    await installer.install();
+  } catch (error) {
+    if (error instanceof Error) actions_core.setFailed(error);
+  }
+}
+
+main();

tsconfig.json

@@ -0,0 +1,15 @@
+{
+    "compilerOptions": {
+        "target": "es6", /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */
+        "module": "commonjs", /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */
+        "outDir": "./lib", /* Redirect output structure to the directory. */
+        "rootDir": "./src", /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
+        "strict": true, /* Enable all strict type-checking options. */
+        "noImplicitAny": true, /* Raise error on expressions and declarations with an implied 'any' type. */
+        "esModuleInterop": true /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
+    },
+    "exclude": [
+        "node_modules",
+        "**/*.test.ts"
+    ]
+}