feat: Azure Key Vault YAML setup support (#285)

* Add key vault linking

* Add keyvault service

* Update tests

* Fix test

* Add tests for coverage and address more pr feedback

* Address final pr comments

package.json

@@ -42,10 +42,12 @@
   "dependencies": {
     "@azure/arm-apimanagement": "^5.1.0",
     "@azure/arm-appservice": "^5.7.0",
+    "@azure/arm-keyvault": "^1.2.1",
     "@azure/arm-resources": "^1.0.1",
     "@azure/arm-storage": "^9.0.1",
     "@azure/ms-rest-nodeauth": "^1.0.1",
     "@azure/storage-blob": "^10.3.0",
+    "acorn": "^7.0.0",
     "axios": "^0.18.0",
     "azure-functions-core-tools": "^2.7.1575",
     "deep-equal": "^1.0.1",

src/armTemplates/resources/functionApp.ts

@@ -58,6 +58,9 @@ export class FunctionAppResource implements ArmResourceTemplateGenerator {
           "apiVersion": "2016-03-01",
           "name": "[parameters('functionAppName')]",
           "location": "[parameters('location')]",
+          "identity": {
+            "type": "SystemAssigned"
+          },
           "dependsOn": [
             "[resourceId('Microsoft.Storage/storageAccounts', parameters('storageAccountName'))]",
             "[concat('microsoft.insights/components/', parameters('appInsightsName'))]"

src/index.ts

@@ -16,6 +16,7 @@ import { AzureApimFunctionPlugin } from "./plugins/apim/azureApimFunctionPlugin"
 import { AzureFuncPlugin } from "./plugins/func/azureFuncPlugin";
 import { AzureOfflinePlugin } from "./plugins/offline/azureOfflinePlugin"
 import { AzureRollbackPlugin } from "./plugins/rollback/azureRollbackPlugin"
+import { AzureKeyVaultPlugin } from "./plugins/identity/azureKeyVaultPlugin"
 
 
 export default class AzureIndex {
@@ -34,6 +35,7 @@ export default class AzureIndex {
     this.serverless.pluginManager.addPlugin(AzureFuncPlugin);
     this.serverless.pluginManager.addPlugin(AzureOfflinePlugin);
     this.serverless.pluginManager.addPlugin(AzureRollbackPlugin);
+    this.serverless.pluginManager.addPlugin(AzureKeyVaultPlugin);
   }
 }
 

src/plugins/identity/azureKeyVaultPlugin.test.ts

@@ -0,0 +1,53 @@
+import Serverless from "serverless";
+import { MockFactory } from "../../test/mockFactory";
+import { invokeHook } from "../../test/utils";
+import { AzureKeyVaultPlugin } from "./azureKeyVaultPlugin";
+
+jest.mock("../../services/azureKeyVaultService.ts");
+import { AzureKeyVaultService } from "../../services/azureKeyVaultService";
+
+describe("Azure Key Vault Plugin", () => {
+  it("is defined", () => {
+    expect(AzureKeyVaultPlugin).toBeDefined();
+  });
+
+  it("can be instantiated", () => {
+    const serverless = MockFactory.createTestServerless();
+    const options: Serverless.Options = MockFactory.createTestServerlessOptions();
+    const plugin = new AzureKeyVaultPlugin(serverless, options);
+
+    expect(plugin).not.toBeNull();
+  });
+
+  it("calls set policy when key vault specified", async () => {
+    const setPolicy = jest.fn();
+
+    AzureKeyVaultService.prototype.setPolicy = setPolicy;
+
+    const sls = MockFactory.createTestServerless();
+    sls.service.provider["keyVault"] = { name: "testVault", resourceGroup: "testGroup"}
+    const options = MockFactory.createTestServerlessOptions();
+    const plugin = new AzureKeyVaultPlugin(sls, options);
+
+    await invokeHook(plugin, "after:deploy:deploy");
+
+    expect(sls.cli.log).toBeCalledWith("Starting KeyVault service setup")
+    expect(setPolicy).toBeCalled();
+    expect(sls.cli.log).lastCalledWith("Finished KeyVault service setup")
+  });
+
+  it("does not call deploy API or deploy functions when \"keyVault\" not included in config", async () => {
+    const setPolicy = jest.fn();
+
+    AzureKeyVaultService.prototype.setPolicy = setPolicy;
+
+    const sls = MockFactory.createTestServerless();
+    const options = MockFactory.createTestServerlessOptions();
+    const plugin = new AzureKeyVaultPlugin(sls, options);
+
+    await invokeHook(plugin, "after:deploy:deploy");
+
+    expect(sls.cli.log).not.toBeCalled()
+    expect(setPolicy).not.toBeCalled();
+  });
+});

src/plugins/identity/azureKeyVaultPlugin.ts

@@ -0,0 +1,27 @@
+import Serverless from "serverless";
+import { AzureBasePlugin } from "../azureBasePlugin";
+import { AzureKeyVaultService } from "../../services/azureKeyVaultService";
+
+export class AzureKeyVaultPlugin extends AzureBasePlugin {
+  public constructor(serverless: Serverless, options: Serverless.Options) {
+    super(serverless, options);
+    this.hooks = {
+      "after:deploy:deploy": this.link.bind(this)
+    };
+  }
+
+  private async link() {
+    const keyVaultConfig = this.serverless.service.provider["keyVault"];
+    if (!keyVaultConfig) {
+      return Promise.resolve();
+    }
+    this.serverless.cli.log("Starting KeyVault service setup");
+
+    const keyVaultService = new AzureKeyVaultService(this.serverless, this.options);
+    const result = await keyVaultService.setPolicy(keyVaultConfig);
+
+    this.serverless.cli.log("Finished KeyVault service setup");
+
+    return result;
+  }
+}

src/services/azureKeyVaultService.test.ts

@@ -0,0 +1,98 @@
+import Serverless from "serverless";
+import { MockFactory } from "../test/mockFactory";
+import {
+  AzureKeyVaultService,
+  AzureKeyVaultConfig
+} from "./azureKeyVaultService";
+
+import { Vaults } from "@azure/arm-keyvault";
+import { FunctionAppService } from "./functionAppService";
+
+describe("Azure Key Vault Service", () => {
+  const options: Serverless.Options = MockFactory.createTestServerlessOptions();
+  const knownVaults = {
+    testVault: {
+      location: "WestUS",
+      properties: {
+        accessPolicies: []
+      }
+    }
+  };
+
+  let serverless: Serverless = MockFactory.createTestServerless();
+
+  beforeEach(() => {
+    Vaults.prototype.createOrUpdate = jest.fn();
+    Vaults.prototype.get = jest.fn(async (resourceGroup, vaultName) => {
+      if (!knownVaults.hasOwnProperty(vaultName)) {
+        throw new Error("No matching vaults");
+      }
+      return knownVaults["testVault"];
+    }) as any;
+
+    FunctionAppService.prototype.get = jest.fn(() => {
+      console.log("testing");
+      return {
+        identity: {
+          tenantId: "tid",
+          principalId: "oid"
+        }
+      } as any;
+    });
+  });
+
+  it("is defined", () => {
+    expect(AzureKeyVaultService).toBeDefined();
+  });
+
+  it("can be instantiated", () => {
+    const service = new AzureKeyVaultService(serverless, options);
+    expect(service).not.toBeNull();
+  });
+
+  it("Throws an error if keyvault doesn't exist", async () => {
+    const service = new AzureKeyVaultService(serverless, options);
+    const keyVault: AzureKeyVaultConfig = MockFactory.createTestKeyVaultConfig(
+      "fake-vault"
+    );
+
+    await expect(service.setPolicy(keyVault)).rejects.toThrowError(
+      "Error: Specified vault not found"
+    );
+    await expect(Vaults.prototype.createOrUpdate).not.toBeCalled();
+  });
+
+  it("Sets correct policy if correct keyvault name is specified", async () => {
+    const keyVault: AzureKeyVaultConfig = MockFactory.createTestKeyVaultConfig(
+      "testVault"
+    );
+    const slsConfig: any = {
+      ...MockFactory.createTestService(
+        MockFactory.createTestSlsFunctionConfig()
+      ),
+      service: "test-sls",
+      provider: {
+        name: "azure",
+        resourceGroup: "test-sls-rg",
+        region: "West US",
+        keyVault
+      }
+    };
+
+    serverless = MockFactory.createTestServerless({
+      service: slsConfig
+    });
+
+    const service = new AzureKeyVaultService(serverless, options);
+    await service.setPolicy(keyVault);
+
+    await expect(Vaults.prototype.createOrUpdate).toBeCalledWith(
+      keyVault.resourceGroup,
+      keyVault.name,
+      {
+        location: knownVaults["testVault"].location,
+        properties: knownVaults["testVault"].properties
+      }
+    );
+  });
+});

src/services/azureKeyVaultService.ts

@@ -0,0 +1,61 @@
+import Serverless from "serverless";
+import { BaseService } from "./baseService";
+import { FunctionAppService } from "./functionAppService";
+import { KeyVaultManagementClient } from "@azure/arm-keyvault";
+import { KeyPermissions, SecretPermissions, Vault } from "@azure/arm-keyvault/esm/models/index";
+
+/**
+ * Defines the Azure Key Vault configuration
+ */
+export interface AzureKeyVaultConfig {
+  /** The name of the azure key vault */
+  name: string;
+  /** The name of the azure resource group with the key vault */
+  resourceGroup: string;
+}
+
+/**
+ * Services for the Key Vault Plugin
+ */
+export class AzureKeyVaultService extends BaseService {
+  private funcApp: FunctionAppService;
+
+  /**
+   * Initialize key vault service and get function app
+   * @param serverless Serverless object
+   * @param options Serverless CLI options
+   */
+  public constructor(serverless: Serverless, options: Serverless.Options) {
+    super(serverless, options);
+    this.funcApp = new FunctionAppService(serverless, options);
+  }
+
+  /**
+   * Sets the KeyVault policy for the function app to allow secrets permissions.
+   * @param keyVaultConfig Azure Key Vault settings
+   */
+  public async setPolicy(keyVaultConfig: AzureKeyVaultConfig) {
+    const subscriptionID = this.subscriptionId;
+
+    const func = await this.funcApp.get();
+    const identity = func.identity;
+    let vault: Vault;
+    const keyVaultClient = new KeyVaultManagementClient(this.credentials, subscriptionID);
+    try {
+      vault = await keyVaultClient.vaults.get(keyVaultConfig.resourceGroup, keyVaultConfig.name)
+    } catch (error) {
+      throw new Error("Error: Specified vault not found")
+    }
+
+    const newEntry = {
+      tenantId: identity.tenantId,
+      objectId: identity.principalId,
+      permissions: {
+        secrets: ["get" as SecretPermissions],
+      }
+    }
+    vault.properties.accessPolicies.push(newEntry);
+
+    return keyVaultClient.vaults.createOrUpdate(keyVaultConfig.resourceGroup, keyVaultConfig.name, {location: vault.location, properties: vault.properties})
+  }
+}

src/test/mockFactory.ts

@@ -323,6 +323,13 @@ export class MockFactory {
     };
   }
 
+  public static createTestKeyVaultConfig(name: string = "testVault") {
+    return {
+      name: name,
+      resourceGroup: "testGroup",
+    };
+  }
+
   public static createTestFunctionMetadata(name: string) {
     return {
       "handler": `${name}.handler`,