Mocking GraphQL in Storybook
Pre-requisites
- Storybook should be running, start it by running
yarn rw storybook
- Have a Cell, Query, or Mutation that you would like to mock
Where to put mock-requests
- Mock-requests placed in a file ending with
.mock.js|ts
are automatically imported and become globally scoped, which means that they will be available in all of your stories. - Mock-requests in a story will be locally scoped and will overwrite globally scoped mocks.
Mocking a Cell's Query
Locate the file ending with .mock.js
in your Cell's folder. This file exports a value named standard
, which is the mock-data that will be returned for your Cell's QUERY
.
export const QUERY = gql`
query UserProfileQuery {
userProfile {
id
}
}
`
// UserProfileCell/UserProfileCell.mock.js
export const standard = {
userProfile: {
id: 42,
},
}
The value assigned to standard
is the mock-data associated to the QUERY
, so modifying the QUERY
means you need to modify the mock-data.
export const QUERY = gql`
query UserProfileQuery {
userProfile {
id
+ name
}
}
`
// UserProfileCell/UserProfileCell.mock.js
export const standard = {
userProfile: {
id: 42,
+ name: 'peterp',
}
}
Behind the scenes: Redwood uses the value associated to
standard
as the second argument tomockGraphQLQuery
.
GraphQL request variables
If you want to dynamically modify mock-data based on a queries variables the standard
export can also be a function, and the first parameter will be an object containing the variables:
export const standard = (variables) => {
return {
userProfile: {
id: 42,
name: 'peterp',
profileImage: `https://example.com/profile.png?size=${variables.size}`,
},
}
}
Mocking a GraphQL Query
If you're not using a Cell, or if you want to overwrite a globally scoped mock, you can use mockGraphQLQuery
:
export const withReallyLongName = () => {
mockGraphQLQuery('UserProfileQuery', () => {
return {
userProfile: {
id: 99,
name: 'Hubert Blaine Wolfeschlegelsteinhausenbergerdorff Sr.'
}
}
})
return <Header />
}
Mocking a GraphQL Mutation
Use mockGraphQLMutation
:
export const standard =
/* ... */
mockGraphQLMutation('UpdateUserName', ({ name }) => {
return {
userProfile: {
id: 99,
name,
},
}
})
Mock-requests that intentionally produce errors
mockGraphQLQuery
and mockGraphQLMutation
have access to ctx
which allows you to modify the mock-response:
mockGraphQLQuery('UserProfileQuery', (_vars, { ctx }) => {
// Forbidden
ctx.status(403)
})