adding save-only and restore-only entry points

removing required

.devcontainer/devcontainer.json

@@ -0,0 +1,14 @@
+{
+	"name": "Node.js & TypeScript",
+	"image": "mcr.microsoft.com/devcontainers/typescript-node:16-bullseye",
+	// Features to add to the dev container. More info: https://containers.dev/implementors/features.
+	// "features": {},
+	// Use 'forwardPorts' to make a list of ports inside the container available locally.
+	// "forwardPorts": [],
+	// Use 'postCreateCommand' to run commands after the container is created.
+	"postCreateCommand": "npm install && npm run build"
+	// Configure tool-specific properties.
+	// "customizations": {},
+	// Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.
+	// "remoteUser": "root"
+}

__tests__/restore.test.ts

@@ -102,7 +102,7 @@ test("restore on GHES with AC available ", async () => {
     const infoMock = jest.spyOn(core, "info");
     const failedMock = jest.spyOn(core, "setFailed");
     const stateMock = jest.spyOn(core, "saveState");
-    const setCacheHitOutputMock = jest.spyOn(actionUtils, "setCacheHitOutput");
+    const setCacheHitOutputMock = jest.spyOn(core, "setOutput");
     const restoreCacheMock = jest
         .spyOn(cache, "restoreCache")
         .mockImplementationOnce(() => {
@@ -116,7 +116,7 @@ test("restore on GHES with AC available ", async () => {
 
     expect(stateMock).toHaveBeenCalledWith("CACHE_KEY", key);
     expect(setCacheHitOutputMock).toHaveBeenCalledTimes(1);
-    expect(setCacheHitOutputMock).toHaveBeenCalledWith(true);
+    expect(setCacheHitOutputMock).toHaveBeenCalledWith("cache-hit", "true");
 
     expect(infoMock).toHaveBeenCalledWith(`Cache restored from key: ${key}`);
     expect(failedMock).toHaveBeenCalledTimes(0);
@@ -270,7 +270,7 @@ test("restore with cache found for key", async () => {
     const infoMock = jest.spyOn(core, "info");
     const failedMock = jest.spyOn(core, "setFailed");
     const stateMock = jest.spyOn(core, "saveState");
-    const setCacheHitOutputMock = jest.spyOn(actionUtils, "setCacheHitOutput");
+    const setCacheHitOutputMock = jest.spyOn(core, "setOutput");
     const restoreCacheMock = jest
         .spyOn(cache, "restoreCache")
         .mockImplementationOnce(() => {
@@ -284,7 +284,7 @@ test("restore with cache found for key", async () => {
 
     expect(stateMock).toHaveBeenCalledWith("CACHE_KEY", key);
     expect(setCacheHitOutputMock).toHaveBeenCalledTimes(1);
-    expect(setCacheHitOutputMock).toHaveBeenCalledWith(true);
+    expect(setCacheHitOutputMock).toHaveBeenCalledWith("cache-hit", "true");
 
     expect(infoMock).toHaveBeenCalledWith(`Cache restored from key: ${key}`);
     expect(failedMock).toHaveBeenCalledTimes(0);
@@ -303,7 +303,7 @@ test("restore with cache found for restore key", async () => {
     const infoMock = jest.spyOn(core, "info");
     const failedMock = jest.spyOn(core, "setFailed");
     const stateMock = jest.spyOn(core, "saveState");
-    const setCacheHitOutputMock = jest.spyOn(actionUtils, "setCacheHitOutput");
+    const setCacheHitOutputMock = jest.spyOn(core, "setOutput");
     const restoreCacheMock = jest
         .spyOn(cache, "restoreCache")
         .mockImplementationOnce(() => {
@@ -317,8 +317,7 @@ test("restore with cache found for restore key", async () => {
 
     expect(stateMock).toHaveBeenCalledWith("CACHE_KEY", key);
     expect(setCacheHitOutputMock).toHaveBeenCalledTimes(1);
-    expect(setCacheHitOutputMock).toHaveBeenCalledWith(false);
-
+    expect(setCacheHitOutputMock).toHaveBeenCalledWith("cache-hit", "false");
     expect(infoMock).toHaveBeenCalledWith(
         `Cache restored from key: ${restoreKey}`
     );

action.yml

@@ -21,7 +21,7 @@ runs:
   using: 'node16'
   main: 'dist/restore/index.js'
   post: 'dist/save/index.js'
-  post-if: 'success()'
+  post-if: success()
 branding:
   icon: 'archive'
   color: 'gray-dark'

dist/save/index.js

@@ -4975,6 +4975,8 @@ var Inputs;
 var Outputs;
 (function (Outputs) {
     Outputs["CacheHit"] = "cache-hit";
+    Outputs["Key"] = "key";
+    Outputs["MatchedKey"] = "matched-key";
 })(Outputs = exports.Outputs || (exports.Outputs = {}));
 var State;
 (function (State) {
@@ -9344,7 +9346,76 @@ function expand(str, isTop) {
 /***/ }),
 /* 307 */,
 /* 308 */,
-/* 309 */,
+/* 309 */
+/***/ (function(__unusedmodule, exports, __webpack_require__) {
+
+"use strict";
+
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    var desc = Object.getOwnPropertyDescriptor(m, k);
+    if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
+      desc = { enumerable: true, get: function() { return m[k]; } };
+    }
+    Object.defineProperty(o, k2, desc);
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
+    Object.defineProperty(o, "default", { enumerable: true, value: v });
+}) : function(o, v) {
+    o["default"] = v;
+});
+var __importStar = (this && this.__importStar) || function (mod) {
+    if (mod && mod.__esModule) return mod;
+    var result = {};
+    if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
+    __setModuleDefault(result, mod);
+    return result;
+};
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.NullStateProvider = exports.StateProvider = void 0;
+const core = __importStar(__webpack_require__(470));
+const constants_1 = __webpack_require__(196);
+class StateProviderBase {
+    constructor() {
+        // eslint-disable-next-line @typescript-eslint/no-unused-vars, @typescript-eslint/no-empty-function
+        this.setState = (key, value) => { };
+        // eslint-disable-next-line @typescript-eslint/no-unused-vars
+        this.getState = (key) => "";
+    }
+    getCacheState() {
+        const cacheKey = this.getState(constants_1.State.CacheMatchedKey);
+        if (cacheKey) {
+            core.debug(`Cache state/key: ${cacheKey}`);
+            return cacheKey;
+        }
+        return undefined;
+    }
+}
+class StateProvider extends StateProviderBase {
+    constructor() {
+        super(...arguments);
+        //setOutput = core.setOutput;
+        this.setState = core.saveState;
+        this.getState = core.getState;
+    }
+}
+exports.StateProvider = StateProvider;
+class NullStateProvider extends StateProviderBase {
+    constructor() {
+        super(...arguments);
+        //setOutput = core.setOutput;
+        this.setState = core.setOutput;
+        // eslint-disable-next-line @typescript-eslint/no-unused-vars
+        this.getState = (key) => "";
+    }
+}
+exports.NullStateProvider = NullStateProvider;
+
+
+/***/ }),
 /* 310 */,
 /* 311 */,
 /* 312 */
@@ -38422,7 +38493,7 @@ var __importStar = (this && this.__importStar) || function (mod) {
     return result;
 };
 Object.defineProperty(exports, "__esModule", { value: true });
-exports.isCacheFeatureAvailable = exports.getInputAsInt = exports.getInputAsArray = exports.isValidEvent = exports.logWarning = exports.getCacheState = exports.setOutputAndState = exports.setCacheHitOutput = exports.setCacheState = exports.isExactKeyMatch = exports.isGhes = void 0;
+exports.isCacheFeatureAvailable = exports.getInputAsInt = exports.getInputAsArray = exports.isValidEvent = exports.logWarning = exports.setCacheHitOutput = exports.isExactKeyMatch = exports.isGhes = void 0;
 const cache = __importStar(__webpack_require__(692));
 const core = __importStar(__webpack_require__(470));
 const constants_1 = __webpack_require__(196);
@@ -38438,29 +38509,10 @@ function isExactKeyMatch(key, cacheKey) {
         }) === 0);
 }
 exports.isExactKeyMatch = isExactKeyMatch;
-function setCacheState(state) {
-    core.saveState(constants_1.State.CacheMatchedKey, state);
-}
-exports.setCacheState = setCacheState;
 function setCacheHitOutput(isCacheHit) {
     core.setOutput(constants_1.Outputs.CacheHit, isCacheHit.toString());
 }
 exports.setCacheHitOutput = setCacheHitOutput;
-function setOutputAndState(key, cacheKey) {
-    setCacheHitOutput(isExactKeyMatch(key, cacheKey));
-    // Store the matched cache key if it exists
-    cacheKey && setCacheState(cacheKey);
-}
-exports.setOutputAndState = setOutputAndState;
-function getCacheState() {
-    const cacheKey = core.getState(constants_1.State.CacheMatchedKey);
-    if (cacheKey) {
-        core.debug(`Cache state/key: ${cacheKey}`);
-        return cacheKey;
-    }
-    return undefined;
-}
-exports.getCacheState = getCacheState;
 function logWarning(message) {
     const warningPrefix = "[warning]";
     core.info(`${warningPrefix}${message}`);
@@ -40892,7 +40944,96 @@ Object.defineProperty(exports, "toPlatformPath", { enumerable: true, get: functi
 //# sourceMappingURL=core.js.map
 
 /***/ }),
-/* 471 */,
+/* 471 */
+/***/ (function(__unusedmodule, exports, __webpack_require__) {
+
+"use strict";
+
+var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    var desc = Object.getOwnPropertyDescriptor(m, k);
+    if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
+      desc = { enumerable: true, get: function() { return m[k]; } };
+    }
+    Object.defineProperty(o, k2, desc);
+}) : (function(o, m, k, k2) {
+    if (k2 === undefined) k2 = k;
+    o[k2] = m[k];
+}));
+var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
+    Object.defineProperty(o, "default", { enumerable: true, value: v });
+}) : function(o, v) {
+    o["default"] = v;
+});
+var __importStar = (this && this.__importStar) || function (mod) {
+    if (mod && mod.__esModule) return mod;
+    var result = {};
+    if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
+    __setModuleDefault(result, mod);
+    return result;
+};
+var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
+    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
+    return new (P || (P = Promise))(function (resolve, reject) {
+        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
+        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
+        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
+        step((generator = generator.apply(thisArg, _arguments || [])).next());
+    });
+};
+Object.defineProperty(exports, "__esModule", { value: true });
+const cache = __importStar(__webpack_require__(692));
+const core = __importStar(__webpack_require__(470));
+const constants_1 = __webpack_require__(196);
+const utils = __importStar(__webpack_require__(443));
+// Catch and log any unhandled exceptions.  These exceptions can leak out of the uploadChunk method in
+// @actions/toolkit when a failed upload closes the file descriptor causing any in-process reads to
+// throw an uncaught exception.  Instead of failing this action, just warn.
+process.on("uncaughtException", e => utils.logWarning(e.message));
+function saveImpl(stateProvider) {
+    return __awaiter(this, void 0, void 0, function* () {
+        try {
+            if (!utils.isCacheFeatureAvailable()) {
+                return;
+            }
+            if (!utils.isValidEvent()) {
+                utils.logWarning(`Event Validation Error: The event type ${process.env[constants_1.Events.Key]} is not supported because it's not tied to a branch or tag ref.`);
+                return;
+            }
+            // If restore has stored a primary key in state, reuse that
+            // Else re-evaluate from inputs
+            const primaryKey = stateProvider.getState(constants_1.State.CachePrimaryKey) ||
+                core.getInput(constants_1.Inputs.Key);
+            if (!primaryKey) {
+                utils.logWarning(`Error retrieving key from state.`);
+                return;
+            }
+            // If matched restore key is same as primary key, then do not save cache
+            // NO-OP in case of SaveOnly action
+            const state = stateProvider.getCacheState();
+            if (utils.isExactKeyMatch(primaryKey, state)) {
+                core.info(`Cache hit occurred on the primary key ${primaryKey}, not saving cache.`);
+                return;
+            }
+            const cachePaths = utils.getInputAsArray(constants_1.Inputs.Path, {
+                required: true
+            });
+            const cacheId = yield cache.saveCache(cachePaths, primaryKey, {
+                uploadChunkSize: utils.getInputAsInt(constants_1.Inputs.UploadChunkSize)
+            });
+            if (cacheId != -1) {
+                core.info(`Cache saved with key: ${primaryKey}`);
+            }
+        }
+        catch (error) {
+            utils.logWarning(error.message);
+        }
+    });
+}
+exports.default = saveImpl;
+
+
+/***/ }),
 /* 472 */,
 /* 473 */,
 /* 474 */,
@@ -47268,29 +47409,6 @@ exports.default = _default;
 
 "use strict";
 
-var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
-    if (k2 === undefined) k2 = k;
-    var desc = Object.getOwnPropertyDescriptor(m, k);
-    if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
-      desc = { enumerable: true, get: function() { return m[k]; } };
-    }
-    Object.defineProperty(o, k2, desc);
-}) : (function(o, m, k, k2) {
-    if (k2 === undefined) k2 = k;
-    o[k2] = m[k];
-}));
-var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
-    Object.defineProperty(o, "default", { enumerable: true, value: v });
-}) : function(o, v) {
-    o["default"] = v;
-});
-var __importStar = (this && this.__importStar) || function (mod) {
-    if (mod && mod.__esModule) return mod;
-    var result = {};
-    if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
-    __setModuleDefault(result, mod);
-    return result;
-};
 var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
     function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
     return new (P || (P = Promise))(function (resolve, reject) {
@@ -47300,49 +47418,15 @@ var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, ge
         step((generator = generator.apply(thisArg, _arguments || [])).next());
     });
 };
+var __importDefault = (this && this.__importDefault) || function (mod) {
+    return (mod && mod.__esModule) ? mod : { "default": mod };
+};
 Object.defineProperty(exports, "__esModule", { value: true });
-const cache = __importStar(__webpack_require__(692));
-const core = __importStar(__webpack_require__(470));
-const constants_1 = __webpack_require__(196);
-const utils = __importStar(__webpack_require__(443));
-// Catch and log any unhandled exceptions.  These exceptions can leak out of the uploadChunk method in
-// @actions/toolkit when a failed upload closes the file descriptor causing any in-process reads to
-// throw an uncaught exception.  Instead of failing this action, just warn.
-process.on("uncaughtException", e => utils.logWarning(e.message));
+const saveImpl_1 = __importDefault(__webpack_require__(471));
+const stateProvider_1 = __webpack_require__(309);
 function run() {
     return __awaiter(this, void 0, void 0, function* () {
-        try {
-            if (!utils.isCacheFeatureAvailable()) {
-                return;
-            }
-            if (!utils.isValidEvent()) {
-                utils.logWarning(`Event Validation Error: The event type ${process.env[constants_1.Events.Key]} is not supported because it's not tied to a branch or tag ref.`);
-                return;
-            }
-            const state = utils.getCacheState();
-            // Inputs are re-evaluted before the post action, so we want the original key used for restore
-            const primaryKey = core.getState(constants_1.State.CachePrimaryKey);
-            if (!primaryKey) {
-                utils.logWarning(`Error retrieving key from state.`);
-                return;
-            }
-            if (utils.isExactKeyMatch(primaryKey, state)) {
-                core.info(`Cache hit occurred on the primary key ${primaryKey}, not saving cache.`);
-                return;
-            }
-            const cachePaths = utils.getInputAsArray(constants_1.Inputs.Path, {
-                required: true
-            });
-            const cacheId = yield cache.saveCache(cachePaths, primaryKey, {
-                uploadChunkSize: utils.getInputAsInt(constants_1.Inputs.UploadChunkSize)
-            });
-            if (cacheId != -1) {
-                core.info(`Cache saved with key: ${primaryKey}`);
-            }
-        }
-        catch (error) {
-            utils.logWarning(error.message);
-        }
+        yield (0, saveImpl_1.default)(new stateProvider_1.StateProvider());
     });
 }
 run();

package.json

@@ -5,7 +5,7 @@
   "description": "Cache dependencies and build outputs",
   "main": "dist/restore/index.js",
   "scripts": {
-    "build": "tsc && ncc build -o dist/restore src/restore.ts && ncc build -o dist/save src/save.ts",
+    "build": "tsc && ncc build -o dist/restore src/restore.ts && ncc build -o dist/save src/save.ts && ncc build -o dist/restore-only src/restoreOnly.ts && ncc build -o dist/save-only src/saveOnly.ts",
     "test": "tsc --noEmit && jest --coverage",
     "lint": "eslint **/*.ts --cache",
     "format": "prettier --write **/*.ts",

restore-only/action.yml

@@ -0,0 +1,27 @@
+name: 'Restore Only Cache'
+description: 'Restore Cache artifacts like dependencies and build outputs to improve workflow execution time'
+author: 'GitHub'
+inputs:
+  path:
+    description: 'The same list of files, directories, and wildcard patterns to restore cache that were used while saving it'
+    required: true
+  key:
+    description: 'An explicit key for restoring the cache'
+    required: true
+  restore-keys:
+    description: 'An ordered list of keys to use for restoring stale cache if no cache hit occurred for key. Note `cache-hit` returns false in this case.'
+    required: false
+outputs:
+  cache-hit:
+    description: 'A boolean value to indicate an exact match was found for the primary key'
+  key:
+    description: 'Key passed in the input to use in subsequent steps of the workflow'
+  matched-key:
+    description: 'Cache key restored'
+runs:
+  using: 'node16'
+  main: '../dist/restore-only/index.js'
+branding:
+  icon: 'archive'
+  color: 'gray-dark'
+  

restore/action.yml

@@ -0,0 +1,27 @@
+name: 'Restore Cache'
+description: 'Restore Cache artifacts like dependencies and build outputs to improve workflow execution time'
+author: 'GitHub'
+inputs:
+  path:
+    description: 'The same list of files, directories, and wildcard patterns to restore cache that were used while saving it'
+    required: true
+  key:
+    description: 'An explicit key for restoring the cache'
+    required: true
+  restore-keys:
+    description: 'An ordered list of keys to use for restoring stale cache if no cache hit occurred for key. Note `cache-hit` returns false in this case.'
+    required: false
+outputs:
+  cache-hit:
+    description: 'A boolean value to indicate an exact match was found for the primary key'
+  key:
+    description: 'Key passed in the input to use in subsequent steps of the workflow'
+  matched-key:
+    description: 'Cache key restored'
+runs:
+  using: 'node16'
+  main: '../dist/restore/index.js'
+branding:
+  icon: 'archive'
+  color: 'gray-dark'
+  

save-only/action.yml

@@ -0,0 +1,22 @@
+name: 'Save Only Cache'
+description: 'Save Cache artifacts like dependencies and build outputs to improve workflow execution time'
+author: 'GitHub'
+inputs:
+  path:
+    description: 'A list of files, directories, and wildcard patterns to cache'
+    required: true
+  key:
+    description: 'An explicit key for saving the cache'
+    required: true
+  upload-chunk-size:
+    description: 'The chunk size used to split up large files during upload, in bytes'
+    required: false
+  matched-key:
+    description: 'Cache key restored from the restore action'
+    required: false
+runs:
+  using: 'node16'
+  main: '../dist/save-only/index.js'
+branding:
+  icon: 'archive'
+  color: 'gray-dark'

save/action.yml

@@ -0,0 +1,22 @@
+name: 'Save Cache'
+description: 'Save Cache artifacts like dependencies and build outputs to improve workflow execution time'
+author: 'GitHub'
+inputs:
+  path:
+    description: 'A list of files, directories, and wildcard patterns to cache'
+    required: true
+  key:
+    description: 'An explicit key for saving the cache'
+    required: true
+  upload-chunk-size:
+    description: 'The chunk size used to split up large files during upload, in bytes'
+    required: false
+  matched-key:
+    description: 'Cache key restored from the restore action'
+    required: false
+runs:
+  using: 'node16'
+  main: '../dist/save/index.js'
+branding:
+  icon: 'archive'
+  color: 'gray-dark'

src/constants.ts

@@ -6,7 +6,9 @@ export enum Inputs {
 }
 
 export enum Outputs {
-    CacheHit = "cache-hit"
+    CacheHit = "cache-hit",
+    Key = "key",
+    MatchedKey = "matched-key"
 }
 
 export enum State {

src/restore.ts

@@ -1,60 +1,8 @@
-import * as cache from "@actions/cache";
-import * as core from "@actions/core";
-
-import { Events, Inputs, State } from "./constants";
-import * as utils from "./utils/actionUtils";
+import { StateProvider } from "./stateProvider";
+import restoreImpl from "./restoreImpl";
 
 async function run(): Promise<void> {
-    try {
-        if (!utils.isCacheFeatureAvailable()) {
-            utils.setCacheHitOutput(false);
-            return;
-        }
-
-        // Validate inputs, this can cause task failure
-        if (!utils.isValidEvent()) {
-            utils.logWarning(
-                `Event Validation Error: The event type ${
-                    process.env[Events.Key]
-                } is not supported because it's not tied to a branch or tag ref.`
-            );
-            return;
-        }
-
-        const primaryKey = core.getInput(Inputs.Key, { required: true });
-        core.saveState(State.CachePrimaryKey, primaryKey);
-
-        const restoreKeys = utils.getInputAsArray(Inputs.RestoreKeys);
-        const cachePaths = utils.getInputAsArray(Inputs.Path, {
-            required: true
-        });
-
-        const cacheKey = await cache.restoreCache(
-            cachePaths,
-            primaryKey,
-            restoreKeys
-        );
-
-        if (!cacheKey) {
-            core.info(
-                `Cache not found for input keys: ${[
-                    primaryKey,
-                    ...restoreKeys
-                ].join(", ")}`
-            );
-
-            return;
-        }
-
-        // Store the matched cache key
-        utils.setCacheState(cacheKey);
-
-        const isExactKeyMatch = utils.isExactKeyMatch(primaryKey, cacheKey);
-        utils.setCacheHitOutput(isExactKeyMatch);
-        core.info(`Cache restored from key: ${cacheKey}`);
-    } catch (error: unknown) {
-        core.setFailed((error as Error).message);
-    }
+    await restoreImpl(new StateProvider());
 }
 
 run();

src/restoreImpl.ts

@@ -0,0 +1,70 @@
+import * as cache from "@actions/cache";
+import * as core from "@actions/core";
+
+import { Events, Inputs, Outputs, State } from "./constants";
+import { IStateProvider } from "./stateProvider";
+import * as utils from "./utils/actionUtils";
+
+async function restoreImpl(
+    stateProvider: IStateProvider
+): Promise<string | undefined> {
+    try {
+        if (!utils.isCacheFeatureAvailable()) {
+            utils.setCacheHitOutput(false);
+            return;
+        }
+
+        // Validate inputs, this can cause task failure
+        if (!utils.isValidEvent()) {
+            utils.logWarning(
+                `Event Validation Error: The event type ${
+                    process.env[Events.Key]
+                } is not supported because it's not tied to a branch or tag ref.`
+            );
+            return;
+        }
+
+        const primaryKey = core.getInput(Inputs.Key, { required: true });
+        stateProvider.setState(State.CachePrimaryKey, primaryKey);
+
+        const restoreKeys = utils.getInputAsArray(Inputs.RestoreKeys);
+        const cachePaths = utils.getInputAsArray(Inputs.Path, {
+            required: true
+        });
+
+        const cacheKey = await cache.restoreCache(
+            cachePaths,
+            primaryKey,
+            restoreKeys
+        );
+
+        if (!cacheKey) {
+            core.info(
+                `Cache not found for input keys: ${[
+                    primaryKey,
+                    ...restoreKeys
+                ].join(", ")}`
+            );
+
+            return;
+        }
+
+        // Store the matched cache key in states
+        stateProvider.setState(State.CacheMatchedKey, cacheKey);
+        core.debug("setState: " + State.CacheMatchedKey + " " + cacheKey);
+
+        const isExactKeyMatch = utils.isExactKeyMatch(
+            core.getInput(Inputs.Key, { required: true }),
+            cacheKey
+        );
+
+        core.setOutput(Outputs.CacheHit, isExactKeyMatch.toString());
+        core.info(`Cache restored from key: ${cacheKey}`);
+
+        return cacheKey;
+    } catch (error: unknown) {
+        core.setFailed((error as Error).message);
+    }
+}
+
+export default restoreImpl;

src/restoreOnly.ts

@@ -0,0 +1,10 @@
+import restoreImpl from "./restoreImpl";
+import { NullStateProvider } from "./stateProvider";
+
+async function run(): Promise<void> {
+    await restoreImpl(new NullStateProvider());
+}
+
+run();
+
+export default run;

src/save.ts

@@ -1,59 +1,8 @@
-import * as cache from "@actions/cache";
-import * as core from "@actions/core";
-
-import { Events, Inputs, State } from "./constants";
-import * as utils from "./utils/actionUtils";
-
-// Catch and log any unhandled exceptions.  These exceptions can leak out of the uploadChunk method in
-// @actions/toolkit when a failed upload closes the file descriptor causing any in-process reads to
-// throw an uncaught exception.  Instead of failing this action, just warn.
-process.on("uncaughtException", e => utils.logWarning(e.message));
+import saveImpl from "./saveImpl";
+import { StateProvider } from "./stateProvider";
 
 async function run(): Promise<void> {
-    try {
-        if (!utils.isCacheFeatureAvailable()) {
-            return;
-        }
-
-        if (!utils.isValidEvent()) {
-            utils.logWarning(
-                `Event Validation Error: The event type ${
-                    process.env[Events.Key]
-                } is not supported because it's not tied to a branch or tag ref.`
-            );
-            return;
-        }
-
-        const state = utils.getCacheState();
-
-        // Inputs are re-evaluted before the post action, so we want the original key used for restore
-        const primaryKey = core.getState(State.CachePrimaryKey);
-        if (!primaryKey) {
-            utils.logWarning(`Error retrieving key from state.`);
-            return;
-        }
-
-        if (utils.isExactKeyMatch(primaryKey, state)) {
-            core.info(
-                `Cache hit occurred on the primary key ${primaryKey}, not saving cache.`
-            );
-            return;
-        }
-
-        const cachePaths = utils.getInputAsArray(Inputs.Path, {
-            required: true
-        });
-
-        const cacheId = await cache.saveCache(cachePaths, primaryKey, {
-            uploadChunkSize: utils.getInputAsInt(Inputs.UploadChunkSize)
-        });
-
-        if (cacheId != -1) {
-            core.info(`Cache saved with key: ${primaryKey}`);
-        }
-    } catch (error: unknown) {
-        utils.logWarning((error as Error).message);
-    }
+    await saveImpl(new StateProvider());
 }
 
 run();

src/saveImpl.ts

@@ -0,0 +1,65 @@
+import * as cache from "@actions/cache";
+import * as core from "@actions/core";
+
+import { Events, Inputs, State } from "./constants";
+import { IStateProvider } from "./stateProvider";
+import * as utils from "./utils/actionUtils";
+
+// Catch and log any unhandled exceptions.  These exceptions can leak out of the uploadChunk method in
+// @actions/toolkit when a failed upload closes the file descriptor causing any in-process reads to
+// throw an uncaught exception.  Instead of failing this action, just warn.
+process.on("uncaughtException", e => utils.logWarning(e.message));
+
+async function saveImpl(stateProvider: IStateProvider): Promise<void> {
+    try {
+        if (!utils.isCacheFeatureAvailable()) {
+            return;
+        }
+
+        if (!utils.isValidEvent()) {
+            utils.logWarning(
+                `Event Validation Error: The event type ${
+                    process.env[Events.Key]
+                } is not supported because it's not tied to a branch or tag ref.`
+            );
+            return;
+        }
+
+        // If restore has stored a primary key in state, reuse that
+        // Else re-evaluate from inputs
+        const primaryKey =
+            stateProvider.getState(State.CachePrimaryKey) ||
+            core.getInput(Inputs.Key);
+
+        if (!primaryKey) {
+            utils.logWarning(`Error retrieving key from state.`);
+            return;
+        }
+
+        // If matched restore key is same as primary key, then do not save cache
+        // NO-OP in case of SaveOnly action
+        const state = stateProvider.getCacheState();
+        if (utils.isExactKeyMatch(primaryKey, state)) {
+            core.info(
+                `Cache hit occurred on the primary key ${primaryKey}, not saving cache.`
+            );
+            return;
+        }
+
+        const cachePaths = utils.getInputAsArray(Inputs.Path, {
+            required: true
+        });
+
+        const cacheId = await cache.saveCache(cachePaths, primaryKey, {
+            uploadChunkSize: utils.getInputAsInt(Inputs.UploadChunkSize)
+        });
+
+        if (cacheId != -1) {
+            core.info(`Cache saved with key: ${primaryKey}`);
+        }
+    } catch (error: unknown) {
+        utils.logWarning((error as Error).message);
+    }
+}
+
+export default saveImpl;

src/saveOnly.ts

@@ -0,0 +1,10 @@
+import saveImpl from "./saveImpl";
+import { NullStateProvider } from "./stateProvider";
+
+async function run(): Promise<void> {
+    await saveImpl(new NullStateProvider());
+}
+
+run();
+
+export default run;

src/stateProvider.ts

@@ -0,0 +1,42 @@
+import * as core from "@actions/core";
+
+import { State } from "./constants";
+
+export interface IStateProvider {
+    //setOutput(key: string, value: string): void;
+    setState(key: string, value: string): void;
+    getState(key: string): string;
+
+    getCacheState(): string | undefined;
+}
+
+class StateProviderBase implements IStateProvider {
+    getCacheState(): string | undefined {
+        const cacheKey = this.getState(State.CacheMatchedKey);
+        if (cacheKey) {
+            core.debug(`Cache state/key: ${cacheKey}`);
+            return cacheKey;
+        }
+
+        return undefined;
+    }
+
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars, @typescript-eslint/no-empty-function
+    setState = (key: string, value: string) => {};
+
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    getState = (key: string) => "";
+}
+
+export class StateProvider extends StateProviderBase {
+    //setOutput = core.setOutput;
+    setState = core.saveState;
+    getState = core.getState;
+}
+
+export class NullStateProvider extends StateProviderBase {
+    //setOutput = core.setOutput;
+    setState = core.setOutput;
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    getState = (key: string) => "";
+}

src/utils/actionUtils.ts

@@ -1,7 +1,7 @@
 import * as cache from "@actions/cache";
 import * as core from "@actions/core";
 
-import { Outputs, RefKey, State } from "../constants";
+import { Outputs, RefKey } from "../constants";
 
 export function isGhes(): boolean {
     const ghUrl = new URL(
@@ -19,30 +19,10 @@ export function isExactKeyMatch(key: string, cacheKey?: string): boolean {
     );
 }
 
-export function setCacheState(state: string): void {
-    core.saveState(State.CacheMatchedKey, state);
-}
-
 export function setCacheHitOutput(isCacheHit: boolean): void {
     core.setOutput(Outputs.CacheHit, isCacheHit.toString());
 }
 
-export function setOutputAndState(key: string, cacheKey?: string): void {
-    setCacheHitOutput(isExactKeyMatch(key, cacheKey));
-    // Store the matched cache key if it exists
-    cacheKey && setCacheState(cacheKey);
-}
-
-export function getCacheState(): string | undefined {
-    const cacheKey = core.getState(State.CacheMatchedKey);
-    if (cacheKey) {
-        core.debug(`Cache state/key: ${cacheKey}`);
-        return cacheKey;
-    }
-
-    return undefined;
-}
-
 export function logWarning(message: string): void {
     const warningPrefix = "[warning]";
     core.info(`${warningPrefix}${message}`);