Reputation: 73
I am trying to unit test aws-sdk
SecretsManager with Jest and running into some issues, I have a simple caching client
import { SecretsManager } from 'aws-sdk';
import { SecretsManagerIntegrationError } from '../errors';
const cache = new Map();
interface SecretsManagerConfig {
region?: string;
}
export class SecretsManagerClient {
secretsManager: SecretsManager;
constructor(config: SecretsManagerConfig) {
this.secretsManager = new SecretsManager(config);
}
async getSecretFromSecretsManager(secretName: string) {
try {
const params = { SecretId: secretName };
const data = await this.secretsManager.getSecretValue(params).promise();
if (data.SecretString) {
return JSON.parse(data.SecretString);
} else {
return Buffer.from(data.SecretBinary as any, 'base64').toString('ascii');
}
} catch (error) {
throw new SecretsManagerIntegrationError(`Error retrieving secrets: ${error}`);
}
}
async getSecret(secretName: string) {
if (!cache.get(secretName)) {
const secret = await this.getSecretFromSecretsManager(secretName);
cache.set(secretName, secret);
return secret;
}
return cache.get(secretName);
}
}
in my test file I have mocked the sdk as so.. seems verbose and something sinon handles pretty straight forward, this assertion fails and I am not sure why..
import { SecretsManagerClient } from '../../src/clients/secretsManagerClient';
jest.mock('aws-sdk', () => {
return {
SecretsManager: jest.fn(() => ({
getSecretValue: jest.fn(() => ({
promise: jest.fn(() => ({
SecretString: JSON.stringify('cool-secrets-here'),
})),
})),
})),
};
});
describe('SecretsManagerClient', () => {
let secretsManager: SecretsManagerClient;
beforeEach(() => {
secretsManager = new SecretsManagerClient({});
});
describe('when a cached value does not exist', () => {
it('queries the secretsManager', async () => {
const getSecretFromSecretsManager = jest.spyOn(secretsManager, 'getSecretFromSecretsManager');
await secretsManager.getSecret('cool-secret');
expect(getSecretFromSecretsManager).toHaveBeenCalledTimes(1);
});
});
<!-- fails --->
describe('when a cached value exists', () => {
it('uses the cached value', async () => {
const getSecretFromSecretsManager = jest.spyOn(secretsManager, 'getSecretFromSecretsManager');
await secretsManager.getSecret('cool-secret');
await secretsManager.getSecret('cool-secret');
expect(getSecretFromSecretsManager).toHaveBeenCalledTimes(1);
});
});
});
Upvotes: 3
Views: 4750
Reputation: 1401
I have achieved this mocking of AWS service using sinon stubs. There is an example of the code as below.
import AWS from 'aws-sdk'
import sinon from 'sinon'
let sinonSandbox
const beforeEach = (done) => {
sinonSandbox = sinon.sandbox.create()
done()
}
const afterEach = done => {
sinonSandbox.restore()
done()
}
lab.test('test name', (done) => {
sinonSandbox.stub(AWS, 'SecretsManager')
.returns({
getSecretValue: () => {
return {
SecretValue: 'Secret-Value'
}
}
})
done()
})
You can also create an aws-sdk-mock npm module which mocks out all the AWS SDK services and methods.
It's really easy to use. Just call AWS.mock with the service, method and a stub function.
AWS.mock('SecretsManager', 'getSecretValue', function(params, callback) {
callback(null, 'success');
});
Then restore the methods after your tests by calling:
AWS.restore('SecretsManager', 'getSecretValue');
Sinon Links:
aws-sdk-mock Links:
https://www.npmjs.com/package/aws-sdk-mock
Upvotes: 2