I'm currently attempting to mock AWS SecretsManager for my unit testing with Jest, and everytime I'm hit with the ConfigError My code is somewhat like this

//index.ts
import SM from "aws-sdk/clients/secretsmanager"
const secretManagerClient = new SM()
...
export const randomMethod = async (a: string, b: string) => {
  let secret
  const personalToken = {
    SecretId: process.env.secretId,
  }
  secretManagerClient
    .getSecretValue(personalToken, (err, data) => {
      if (err) {
        console.error(`[SECRETS MANAGER] Error fetching personal token : ${err}`)
      } else if (data && data.SecretString) {
        secret = data.SecretString
      }
    })
}

My mock goes like this :

//index.test.js
const mockGetSecretValue = jest.fn((SecretId) => {
  switch (SecretId) {
    case process.env.GITHUB_PERSONAL_TOKEN:
      return {
        SecretString: process.env.GITHUB_PERSONAL_TOKEN_VALUE,
      }
    default:
      throw Error("secret not found")
  }
})

jest.mock("aws-sdk/clients/secretsmanager", () => {
  return jest.fn(() => {
    return {
      getSecretValue: jest.fn(({ SecretId }) => {
        return mockGetSecretValue(SecretId)
      }),
      promise: jest.fn(),
    }
  })
})

However, I get this error thrown at me : ConfigError: Missing region in config, which I understand to some extent, however I don't understand why it occurs here in the mocking part...

Thanks in advance!

EDIT: Thanks to the 1st answer, I've managed to stop having this error. However, the getSecretValue() method is not returning the Secret value I want.

CodePudding user response：

You should NOT use the callback of .getSecretValue() method with .promise() together. Just choose one of them. The error means you didn't mock the secretsmanager class correctly of aws-sdk.

E.g.

index.ts:

import SM from 'aws-sdk/clients/secretsmanager';
const secretManagerClient = new SM();

export const randomMethod = async () => {
  const personalToken = {
    SecretId: process.env.secretId || '',
  };
  try {
    const data = await secretManagerClient.getSecretValue(personalToken).promise();
    return data.SecretString;
  } catch (err) {
    console.error(`[SECRETS MANAGER] Error fetching personal token : ${err}`);
  }
};

index.test.ts:

import { randomMethod } from '.';
import SM from 'aws-sdk/clients/secretsmanager';
import { mocked } from 'ts-jest/utils';
import { PromiseResult } from 'aws-sdk/lib/request';

jest.mock('aws-sdk/clients/secretsmanager', () => {
  const mSecretManagerClient = {
    getSecretValue: jest.fn().mockReturnThis(),
    promise: jest.fn(),
  };
  return jest.fn(() => mSecretManagerClient);
});

describe('69977310', () => {
  test('should get secret value', async () => {
    process.env.secretId = 's1';
    const mSecretManagerClient = mocked<InstanceType<typeof SM>>(new SM());
    const mGetSecretValueRequest = mocked(mSecretManagerClient.getSecretValue());

    mGetSecretValueRequest.promise.mockResolvedValue({
      SecretString: JSON.stringify({ password: '123456' }),
    } as PromiseResult<any, any>);
    const actual = await randomMethod();
    expect(actual).toEqual(JSON.stringify({ password: '123456' }));
    expect(mSecretManagerClient.getSecretValue as jest.Mocked<any>).toBeCalledWith({ SecretId: 's1' });
  });

  test('should throw error', async () => {
    process.env.secretId = 's1';
    const logSpy = jest.spyOn(console, 'error').mockImplementation(() => 'suppress error log for testing');
    const mSecretManagerClient = mocked<InstanceType<typeof SM>>(new SM());
    const mGetSecretValueRequest = mocked(mSecretManagerClient.getSecretValue());

    const mError = new Error('network');
    mGetSecretValueRequest.promise.mockRejectedValue(mError);
    await randomMethod();
    expect(logSpy).toBeCalledWith(`[SECRETS MANAGER] Error fetching personal token : ${mError}`);
    expect(mSecretManagerClient.getSecretValue as jest.Mocked<any>).toBeCalledWith({ SecretId: 's1' });
  });
});

test result:

 PASS  examples/69977310/index.test.ts (7.722 s)
  69977310
    ✓ should get secret value (4 ms)
    ✓ should throw error (1 ms)

----------|---------|----------|---------|---------|-------------------
File      | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
----------|---------|----------|---------|---------|-------------------
All files |     100 |       50 |     100 |     100 |                   
 index.ts |     100 |       50 |     100 |     100 | 6                 
----------|---------|----------|---------|---------|-------------------
Test Suites: 1 passed, 1 total
Tests:       2 passed, 2 total
Snapshots:   0 total
Time:        8.282 s, estimated 10 s

package versions:

"aws-sdk": "^2.875.0",
"typescript": "^4.1.2",
"jest": "^26.6.3",

CodePudding user response：

I've overlooked the fact that I was using a callback in order to bypass the promise().

The following is the correct code:

const mockGetSecretValue = jest.fn((SecretId, callback) => {
  console.log("secretId", SecretId)
  switch (SecretId) {
    case process.env.GITHUB_PERSONAL_TOKEN:
      const data = {
        SecretString: process.env.GITHUB_PERSONAL_TOKEN_VALUE,
      }
      callback(null, data)
      break;
    default:
      const err = new Error("secret not found")
      throw err
  }
})

jest.mock("aws-sdk/clients/secretsmanager", () => {
  return jest.fn(() => {
    return {
      promise: jest.fn(),
      getSecretValue: jest.fn(({ SecretId }, callback) => {
        return mockGetSecretValue(SecretId, callback)
      }),
    }
  })
})

Thanks again for your help @slideshowp2!