feat: specify subscription ID in serverless yaml

Author: neerajmandal

src/plugins/login/azureLoginPlugin.test.ts

@@ -105,7 +105,7 @@ describe("Login Plugin", () => {
     expect(AzureLoginService.interactiveLogin).toBeCalled()
     expect(sls.variables["subscriptionId"]).toEqual("test-subs-id");
     expect(sls.cli.log).toBeCalledWith("Using subscription ID: test-subs-id");
-  })
+  });
 
   it("Uses the default subscription ID" , async () => {
     const sls = MockFactory.createTestServerless();
@@ -115,4 +115,14 @@ describe("Login Plugin", () => {
     expect(sls.variables["subscriptionId"]).toEqual("azureSubId");
     expect(sls.cli.log).toBeCalledWith("Using subscription ID: azureSubId");
   });
+  
+  it("Uses the subscription ID specified in serverless yaml", async () => {
+    const sls = MockFactory.createTestServerless();
+    const opt = MockFactory.createTestServerlessOptions();
+    sls.service.provider["subscriptionId"] = "test-subs-id";
+    await invokeLoginHook(false, sls, opt);
+    expect(AzureLoginService.interactiveLogin).toBeCalled()
+    expect(sls.variables["subscriptionId"]).toEqual("test-subs-id");
+    expect(sls.cli.log).toBeCalledWith("Using subscription ID: test-subs-id");
+  });
 });

src/plugins/login/azureLoginPlugin.ts

@@ -28,7 +28,7 @@ export class AzureLoginPlugin extends AzureBasePlugin<AzureLoginOptions> {
       this.serverless.variables["azureCredentials"] = authResult.credentials;
       // Use environment variable for sub ID or use the first subscription in the list (service principal can
       // have access to more than one subscription)
-      this.serverless.variables["subscriptionId"] = this.options.subscriptionId || process.env.azureSubId || authResult.subscriptions[0].id;
+      this.serverless.variables["subscriptionId"] = this.options.subscriptionId || process.env.azureSubId || this.serverless.service.provider["subscriptionId"] || authResult.subscriptions[0].id;
       this.serverless.cli.log(`Using subscription ID: ${this.serverless.variables["subscriptionId"]}`);
     }
     catch (e) {