feat: optionally skip configure

README.md

@@ -37,4 +37,30 @@ jobs:
 | `FASTLY_API_TOKEN`   | string  | personal [Fastly API token](https://manage.fastly.com/account/personal/tokens)                          |
 
 
+## alternative usage
+
+This workflow can also be used to only install the Fastly CLI. If you want to use an API token that has a strictly limited permission grant, you will need to use this option.
+
+To do that pass an environment variable `SKIP_CONFIGURE` with any value.  The `FASTLY_API_TOKEN` is not required in this case.
+
+For steps following the installation, you will need to provide the CLI with an API token, by either exporting a `FASTLY_API_TOKEN` environment variable, or by providing it to the CLI explicitly as part of the command line. See the [Fastly CLI documentation](https://developer.fastly.com/reference/cli/#configuring) for details.
+
+### example
+
+```yml
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+    - name: Setup Fastly CLI
+      uses: softprops/setup-fastly-cli@v1
+      env:
+        SKIP_CONFIGURE: yes
+    - name: Purge Fastly
+        FASTLY_API_TOKEN: ${{ secrets.FASTLY_API_TOKEN }}
+      run: fastly purge --key "*/beepboop"
+```
+
 Doug Tangren (softprops) 2020

src/main.ts

@@ -44,15 +44,20 @@ async function run() {
     if (!version) {
       throw new Error("Failed to resolve latest version");
     }
-    const fastlyToken = process.env.FASTLY_API_TOKEN;
-    if (!fastlyToken) {
-      throw new Error("Please provide an FASTLY_API_TOKEN env variable");
-    }
 
     await install(version, os.platform());
-    await exec.exec("fastly", ["configure", "--token", fastlyToken]);
+
+    const doConfigure = process.env.SKIP_CONFIGURE == undefined;
+    if (doConfigure) {
+      const fastlyToken = `${process.env.FASTLY_API_TOKEN}`;
+      if (fastlyToken == "") {
+        throw new Error("Expected FASTLY_API_TOKEN to not be empty");
+      }
+
+      await exec.exec("fastly", ["configure", "--token", fastlyToken]);
+    }
   } catch (error) {
-    setFailed(error.message);
+    setFailed((error as Error).message);
   }
 }