feat: Introduced `restore-only` flag

README.md

@@ -90,6 +90,7 @@ If you are using a `self-hosted` Windows runner, `GNU tar` and `zstd` are requir
 * `enableCrossOsArchive` - An optional boolean when enabled, allows Windows runners to save or restore caches that can be restored or saved respectively on other platforms. Default: `false`
 * `fail-on-cache-miss` - Fail the workflow if cache entry is not found. Default: `false`
 * `lookup-only` - If true, only checks if cache entry exists and skips download. Does not change save cache behavior. Default: `false`
+* `restore-only` - If true, only restores cache and skips save cache behavior. Default: `false`. Set it to `${{ github.event.repository != null && github.ref_name != github.event.repository.default_branch }}` to only save the cache when running on the default branch.
 
 #### Environment Variables
 

__tests__/saveImpl.test.ts

@@ -406,3 +406,34 @@ test("save with valid inputs uploads a cache", async () => {
 
     expect(failedMock).toHaveBeenCalledTimes(0);
 });
+
+test("save with restore-only should no-op", async () => {
+    const primaryKey = "Linux-node-bb828da54c148048dd17899ba9fda624811cfb43";
+    const savedCacheKey = "Linux-node-";
+
+    jest.spyOn(core, "getState")
+        // Cache Entry State
+        .mockImplementationOnce(() => {
+            return savedCacheKey;
+        })
+        // Cache Key State
+        .mockImplementationOnce(() => {
+            return primaryKey;
+        });
+
+    const inputPath = "node_modules";
+    testUtils.setInput(Inputs.Path, inputPath);
+
+    testUtils.setInput(Inputs.RestoreOnly, "true");
+
+    const infoMock = jest.spyOn(core, "info");
+
+    const saveCacheMock = jest.spyOn(cache, "saveCache");
+
+    await saveImpl(new StateProvider());
+
+    expect(saveCacheMock).toHaveBeenCalledTimes(0);
+    expect(infoMock).toHaveBeenCalledWith(
+        "Skipping saving cache as 'restore-only' option is set."
+    );
+});

action.yml

@@ -26,6 +26,10 @@ inputs:
     description: 'Check if a cache entry exists for the given input(s) (key, restore-keys) without downloading the cache'
     default: 'false'
     required: false
+  restore-only:
+    description: 'Downloads the cache if it exists, but skips saving it at the end of the job'
+    default: 'false'
+    required: false
   save-always:
     description: 'Run the post step to save the cache even if another step before fails'
     default: 'false'

dist/restore-only/index.js

@@ -46306,7 +46306,8 @@ var Inputs;
     Inputs["UploadChunkSize"] = "upload-chunk-size";
     Inputs["EnableCrossOsArchive"] = "enableCrossOsArchive";
     Inputs["FailOnCacheMiss"] = "fail-on-cache-miss";
-    Inputs["LookupOnly"] = "lookup-only"; // Input for cache, restore action
+    Inputs["LookupOnly"] = "lookup-only";
+    Inputs["RestoreOnly"] = "restore-only"; // Input for cache, restore action
 })(Inputs || (exports.Inputs = Inputs = {}));
 var Outputs;
 (function (Outputs) {

dist/restore/index.js

@@ -46306,7 +46306,8 @@ var Inputs;
     Inputs["UploadChunkSize"] = "upload-chunk-size";
     Inputs["EnableCrossOsArchive"] = "enableCrossOsArchive";
     Inputs["FailOnCacheMiss"] = "fail-on-cache-miss";
-    Inputs["LookupOnly"] = "lookup-only"; // Input for cache, restore action
+    Inputs["LookupOnly"] = "lookup-only";
+    Inputs["RestoreOnly"] = "restore-only"; // Input for cache, restore action
 })(Inputs || (exports.Inputs = Inputs = {}));
 var Outputs;
 (function (Outputs) {

dist/save-only/index.js

@@ -46306,7 +46306,8 @@ var Inputs;
     Inputs["UploadChunkSize"] = "upload-chunk-size";
     Inputs["EnableCrossOsArchive"] = "enableCrossOsArchive";
     Inputs["FailOnCacheMiss"] = "fail-on-cache-miss";
-    Inputs["LookupOnly"] = "lookup-only"; // Input for cache, restore action
+    Inputs["LookupOnly"] = "lookup-only";
+    Inputs["RestoreOnly"] = "restore-only"; // Input for cache, restore action
 })(Inputs || (exports.Inputs = Inputs = {}));
 var Outputs;
 (function (Outputs) {
@@ -46401,6 +46402,10 @@ function saveImpl(stateProvider) {
                 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 (utils.getInputAsBool(constants_1.Inputs.RestoreOnly)) {
+                core.info("Skipping saving cache as 'restore-only' option is set.");
+                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) ||

dist/save/index.js

@@ -46306,7 +46306,8 @@ var Inputs;
     Inputs["UploadChunkSize"] = "upload-chunk-size";
     Inputs["EnableCrossOsArchive"] = "enableCrossOsArchive";
     Inputs["FailOnCacheMiss"] = "fail-on-cache-miss";
-    Inputs["LookupOnly"] = "lookup-only"; // Input for cache, restore action
+    Inputs["LookupOnly"] = "lookup-only";
+    Inputs["RestoreOnly"] = "restore-only"; // Input for cache, restore action
 })(Inputs || (exports.Inputs = Inputs = {}));
 var Outputs;
 (function (Outputs) {
@@ -46401,6 +46402,10 @@ function saveImpl(stateProvider) {
                 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 (utils.getInputAsBool(constants_1.Inputs.RestoreOnly)) {
+                core.info("Skipping saving cache as 'restore-only' option is set.");
+                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) ||

src/constants.ts

@@ -5,7 +5,8 @@ export enum Inputs {
     UploadChunkSize = "upload-chunk-size", // Input for cache, save action
     EnableCrossOsArchive = "enableCrossOsArchive", // Input for cache, restore, save action
     FailOnCacheMiss = "fail-on-cache-miss", // Input for cache, restore action
-    LookupOnly = "lookup-only" // Input for cache, restore action
+    LookupOnly = "lookup-only", // Input for cache, restore action
+    RestoreOnly = "restore-only" // Input for cache, restore action
 }
 
 export enum Outputs {

src/saveImpl.ts

@@ -32,6 +32,11 @@ export async function saveImpl(
             return;
         }
 
+        if (utils.getInputAsBool(Inputs.RestoreOnly)) {
+            core.info("Skipping saving cache as 'restore-only' option is set.");
+            return;
+        }
+
         // If restore has stored a primary key in state, reuse that
         // Else re-evaluate from inputs
         const primaryKey =

src/utils/testUtils.ts

@@ -16,6 +16,7 @@ interface CacheInput {
     enableCrossOsArchive?: boolean;
     failOnCacheMiss?: boolean;
     lookupOnly?: boolean;
+    restoreOnly?: boolean;
 }
 
 export function setInputs(input: CacheInput): void {
@@ -32,6 +33,8 @@ export function setInputs(input: CacheInput): void {
         setInput(Inputs.FailOnCacheMiss, input.failOnCacheMiss.toString());
     input.lookupOnly !== undefined &&
         setInput(Inputs.LookupOnly, input.lookupOnly.toString());
+    input.restoreOnly !== undefined &&
+        setInput(Inputs.RestoreOnly, input.restoreOnly.toString());
 }
 
 export function clearInputs(): void {
@@ -42,4 +45,5 @@ export function clearInputs(): void {
     delete process.env[getInputName(Inputs.EnableCrossOsArchive)];
     delete process.env[getInputName(Inputs.FailOnCacheMiss)];
     delete process.env[getInputName(Inputs.LookupOnly)];
+    delete process.env[getInputName(Inputs.RestoreOnly)];
 }