Node, Sinon, Mocha mock default exported function - node.js

Question

I'm trying to mock the import nodeVault so that I can set the return value for the read function.
I have the following code:
import nodeVault from 'node-vault';
const getVaultClient = (vaultToken) => {
return nodeVault({
apiVersion: 'v1',
endpoint: process.env.VAULT_URL,
token: vaultToken.auth.client_token,
});
}
const getCredentialsFromVault = async () => {
const vaultToken = await getVaultToken();
const vault = getVaultClient(vaultToken);
const { data } = await vault.read(process.env.VAULT_SECRET_PATH);
return { client_id: data.client_id, client_secret: data.client_secret, grant_type: 'client_credentials' };
};
I then have a unit test:
describe('AttributeLoad', () => {
let sandbox;
let pedApiMock;
let authApiMock;
let vaultAuthenticateMock;
let nodeVaultClientMock;
beforeEach(() => {
sandbox = createSandbox();
process.env = { VAULT_URL: 'testVault', VAULT_SECRET_PATH: 'testPath' };
pedApiMock = sandbox.stub(attributeLoader.pedApi, 'post');
authApiMock = sandbox.stub(attributeLoader.authApi, 'post');
vaultAuthenticateMock = sandbox.stub(vaultAuthAws.prototype, 'authenticate');
nodeVaultClientMock = sandbox.stub(nodeVault.prototype, ''); --------> Not sure what should go here
I have tried read and constructor
});
afterEach(() => {
sandbox.restore();
});
it('Should call api with correct request body and correctly filter successes and rejections', async () => {
const expectedOutput = {
rejectedLines: [
....
],
validLines: [
.....
]
};
const mockAuthResponse = {
data: {
access_token: 'mocktoken',
},
};
const mockVaultToken = {
auth: {
client_token: ''
}
};
const expectedAuthParams = {
client_id: '',
client_secret: '',
grant_type: 'client_credentials',
};
const mockVaultData = {
data: {
client_id: '',
client_secret: '',
}
};
pedApiMock.returns(Promise.resolve(mockResponse));
authApiMock.returns(Promise.resolve(mockAuthResponse));
vaultAuthenticateMock.returns(Promise.resolve(mockVaultToken));
nodeVaultClientMock.returns(Promise.resolve(mockVaultData));
const finalTestData = await attributeLoader.load(testInputData);
assert.calledWith(authApiMock, expectedAuthParams);
expect(finalTestData.rejectedLines).to.deep.equal(expectedOutput.rejectedLines);
expect(finalTestData.validLines).to.deep.equal(expectedOutput.validLines);
});
});
Everything I try gives this error:
"before each" hook for "Should call api with correct request body and correctly filter successes and rejections":
TypeError: Cannot stub non-existent property read* ---> or any function I try to mock
I've also tried to spy on nodeVault.
Any and all help would be greatly appreciated

Answer 1

So after some more digging I was able to mock node vault by using proxyquire:
import proxyquire from 'proxyquire';
const attributeLoader = proxyquire('../src/attributeLoader', { 'node-vault': () => { return { read: () => mockVaultData } } });
and that fixed it.