@heetch/cypress-mock-openapi
v1.0.2
Published
Cypress command to stub network requests using OpenAPI examples
Downloads
861
Readme
@heetch/cypress-mock-openapi
This package contains a Cypress plugin and command to mock and validate responses in tests using an OpenAPI (Swagger) contract.
Installation
npm install --dev @heetch/cypress-mock-openapi
OR
yarn add --dev @heetch/cypress-mock-openapi
Configuration
After installing the package, configure Cypress with the following environment variables:
{
"openapiPath": "test/openapi.yaml",
"apiPrefix": "http://api-prefix" // Optional
}
The
apiPrefix
can be set globally but also overridden in both commands (or omitted completely).
In your Cypress plugin file:
import getOpenAPIResponse from '@heetch/cypress-mock-openapi/dist/plugin';
module.exports = (on) => {
on('task', {
getOpenAPIResponse,
});
};
Either in your support/index.js file or commands.js (for a standard configuration):
import '@heetch/cypress-mock-openapi';
Basic usage
cy.mockWithOpenAPI(options)
This command will:
- Intercept a network request based on the passed options
- Search for the matching operation in the configured OpenAPI file
- Return the response of the operation and method based on the exampleKey
Note: The first example defined in the OpenAPI contract will be used if none are specified
# OpenAPI operation for GET http://my-api.com/users
examples:
ACTIVE:
value:
users:
- name: Paco
active: true
it('Displays a list of users', () => {
// Set up the mock for GET http://my-api.com/users
cy.mockWithOpenAPI({
apiPrefix: 'http://my-api.com',
url: '/users',
}).as('getActiveUsers');
// When the page loads, fetch /users
cy.get('html').then(() => fetch('http://my-api.com/users'));
// Await the results of the interception and make assertions on the mocked response
cy.wait('@getActiveUsers').then((interception) => {
expect(interception.response.statusCode).to.eql(200);
expect(interception.response.body).to.eql({
users: [{ name: 'Paco', active: true }],
});
});
});
cy.validateWithOpenAPI(options)
This command can be used to validate that your API returns a response that conforms to the OpenAPI contract (both the request and the response). It will perform the request with the provided options and return the actual response if the validation passes.
If the validation fails, an error will be thrown that contains a list of contract violations. For example:
it('Throws an error if the validation fails', () => {
cy.validateWithOpenAPI({
url: '/users',
headers: {
Authorization: 'Password',
}
});
// Throws an error with the following information returned:
{
message: "The response doesn't match the OpenAPI contract",
violations: {
"body.users[0]": "required: should have required property 'age'",
}
}
});
Note: This command doesn't intercept requests
Options reference
mockWithOpenAPI(options)
| Name | Type | Optional | Default | Example | Description |
| ---------- | -------- | -------- | ----------- | --------------------------------------------------------- | --------------------------------------------------------------------------------- |
| apiPrefix | String
| false
| undefined
| http://my-api.com
| A prefix for API calls. Can also be configured global using Cypress env variables |
| url | String
| false
| undefined
| /users
/dogs?cute=true
| The pathname and query parameters of the request |
| exampleKey | String
| true
| undefined
| 'OK' | By default the first example will be used if none are specified |
| method | String
| true
| 'GET'
| https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods | Any supported HTTP method |
validateWithOpenAPI(options)
| Name | Type | Optional | Default | Example | Description |
| --------- | -------- | -------- | ----------- | --------------------------------------------------------- | --------------------------------------------------------------------------------- |
| apiPrefix | String
| false
| undefined
| http://my-api.com
| A prefix for API calls. Can also be configured global using Cypress env variables |
| url | String
| false
| undefined
| /users
/dogs?cute=true
| The pathname and query parameters of the request |
| method | String
| true
| 'GET'
| https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods | Any supported HTTP method |
| headers | Object
| true
| {}
| { Authorization: 'Basic 1234' }
| The headers required to perform the actual HTTP request |
Developing and testing locally
First, install the package dependencies for this workspace at the root of the repo, then run yarn install
or npm install
in this folder.
Files:
- Command:
packages/cypress-mock-openapi/src/index.js
- Plugin:
packages/cypress-mock-openapi/src/plugin.js
- Mock server data:
packages/cypress-mock-openapi/test/json/db.json
- Spec:
packages/cypress-mock-openapi/test/specs/mock.spec.js
Commands:
yarn test:open # Opens the Cypress UI
yarn test # Runs the tests in a headless browser