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mockServiceWorker.js
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mockServiceWorker.js
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/* eslint-disable */
/* tslint:disable */
/**
* Mock Service Worker (<PACKAGE_VERSION>).
* @see https://github.com/mswjs/msw
* - Please do NOT modify this file.
* - Please do NOT serve this file on production.
*/
const INTEGRITY_CHECKSUM = '<INTEGRITY_CHECKSUM>'
const activeClientIds = new Set()
self.addEventListener('install', function () {
self.skipWaiting()
})
self.addEventListener('activate', function (event) {
event.waitUntil(self.clients.claim())
})
self.addEventListener('message', async function (event) {
const clientId = event.source.id
if (!clientId || !self.clients) {
return
}
const client = await self.clients.get(clientId)
if (!client) {
return
}
const allClients = await self.clients.matchAll({
type: 'window',
})
switch (event.data) {
case 'KEEPALIVE_REQUEST': {
sendToClient(client, {
type: 'KEEPALIVE_RESPONSE',
})
break
}
case 'INTEGRITY_CHECK_REQUEST': {
sendToClient(client, {
type: 'INTEGRITY_CHECK_RESPONSE',
payload: INTEGRITY_CHECKSUM,
})
break
}
case 'MOCK_ACTIVATE': {
activeClientIds.add(clientId)
sendToClient(client, {
type: 'MOCKING_ENABLED',
payload: true,
})
break
}
case 'MOCK_DEACTIVATE': {
activeClientIds.delete(clientId)
break
}
case 'CLIENT_CLOSED': {
activeClientIds.delete(clientId)
const remainingClients = allClients.filter((client) => {
return client.id !== clientId
})
// Unregister itself when there are no more clients
if (remainingClients.length === 0) {
self.registration.unregister()
}
break
}
}
})
self.addEventListener('fetch', function (event) {
const { request } = event
const accept = request.headers.get('accept') || ''
// Bypass server-sent events.
if (accept.includes('text/event-stream')) {
return
}
// Bypass navigation requests.
if (request.mode === 'navigate') {
return
}
// Opening the DevTools triggers the "only-if-cached" request
// that cannot be handled by the worker. Bypass such requests.
if (request.cache === 'only-if-cached' && request.mode !== 'same-origin') {
return
}
// Bypass all requests when there are no active clients.
// Prevents the self-unregistered worked from handling requests
// after it's been deleted (still remains active until the next reload).
if (activeClientIds.size === 0) {
return
}
// Generate unique request ID.
const requestId = Math.random().toString(16).slice(2)
event.respondWith(
handleRequest(event, requestId).catch((error) => {
if (error.name === 'NetworkError') {
console.warn(
'[MSW] Successfully emulated a network error for the "%s %s" request.',
request.method,
request.url,
)
return
}
// At this point, any exception indicates an issue with the original request/response.
console.error(
`\
[MSW] Caught an exception from the "%s %s" request (%s). This is probably not a problem with Mock Service Worker. There is likely an additional logging output above.`,
request.method,
request.url,
`${error.name}: ${error.message}`,
)
}),
)
})
async function handleRequest(event, requestId) {
const client = await resolveMainClient(event)
const response = await getResponse(event, client, requestId)
// Send back the response clone for the "response:*" life-cycle events.
// Ensure MSW is active and ready to handle the message, otherwise
// this message will pend indefinitely.
if (client && activeClientIds.has(client.id)) {
;(async function () {
const clonedResponse = response.clone()
sendToClient(client, {
type: 'RESPONSE',
payload: {
requestId,
type: clonedResponse.type,
ok: clonedResponse.ok,
status: clonedResponse.status,
statusText: clonedResponse.statusText,
body:
clonedResponse.body === null ? null : await clonedResponse.text(),
headers: Object.fromEntries(clonedResponse.headers.entries()),
redirected: clonedResponse.redirected,
},
})
})()
}
return response
}
// Resolve the main client for the given event.
// Client that issues a request doesn't necessarily equal the client
// that registered the worker. It's with the latter the worker should
// communicate with during the response resolving phase.
async function resolveMainClient(event) {
const client = await self.clients.get(event.clientId)
if (client.frameType === 'top-level') {
return client
}
const allClients = await self.clients.matchAll({
type: 'window',
})
return allClients
.filter((client) => {
// Get only those clients that are currently visible.
return client.visibilityState === 'visible'
})
.find((client) => {
// Find the client ID that's recorded in the
// set of clients that have registered the worker.
return activeClientIds.has(client.id)
})
}
async function getResponse(event, client, requestId) {
const { request } = event
const clonedRequest = request.clone()
function passthrough() {
// Clone the request because it might've been already used
// (i.e. its body has been read and sent to the cilent).
const headers = Object.fromEntries(clonedRequest.headers.entries())
// Remove MSW-specific request headers so the bypassed requests
// comply with the server's CORS preflight check.
// Operate with the headers as an object because request "Headers"
// are immutable.
delete headers['x-msw-bypass']
return fetch(clonedRequest, { headers })
}
// Bypass mocking when the client is not active.
if (!client) {
return passthrough()
}
// Bypass initial page load requests (i.e. static assets).
// The absence of the immediate/parent client in the map of the active clients
// means that MSW hasn't dispatched the "MOCK_ACTIVATE" event yet
// and is not ready to handle requests.
if (!activeClientIds.has(client.id)) {
return passthrough()
}
// Bypass requests with the explicit bypass header.
// Such requests can be issued by "ctx.fetch()".
if (request.headers.get('x-msw-bypass') === 'true') {
return passthrough()
}
// Create a communication channel scoped to the current request.
// This way events can be exchanged outside of the worker's global
// "message" event listener (i.e. abstracted into functions).
const operationChannel = new BroadcastChannel(
`msw-response-stream-${requestId}`,
)
// Notify the client that a request has been intercepted.
const clientMessage = await sendToClient(client, {
type: 'REQUEST',
payload: {
id: requestId,
url: request.url,
method: request.method,
headers: Object.fromEntries(request.headers.entries()),
cache: request.cache,
mode: request.mode,
credentials: request.credentials,
destination: request.destination,
integrity: request.integrity,
redirect: request.redirect,
referrer: request.referrer,
referrerPolicy: request.referrerPolicy,
body: await request.text(),
bodyUsed: request.bodyUsed,
keepalive: request.keepalive,
},
})
switch (clientMessage.type) {
case 'MOCK_RESPONSE': {
return respondWithMock(clientMessage.payload)
}
case 'MOCK_RESPONSE_START': {
return respondWithMockStream(operationChannel, clientMessage.payload)
}
case 'MOCK_NOT_FOUND': {
return passthrough()
}
case 'NETWORK_ERROR': {
const { name, message } = clientMessage.payload
const networkError = new Error(message)
networkError.name = name
// Rejecting a "respondWith" promise emulates a network error.
throw networkError
}
case 'INTERNAL_ERROR': {
const parsedBody = JSON.parse(clientMessage.payload.body)
console.error(
`\
[MSW] Uncaught exception in the request handler for "%s %s":
${parsedBody.location}
This exception has been gracefully handled as a 500 response, however, it's strongly recommended to resolve this error, as it indicates a mistake in your code. If you wish to mock an error response, please see this guide: https://mswjs.io/docs/recipes/mocking-error-responses\
`,
request.method,
request.url,
)
return respondWithMock(clientMessage.payload)
}
}
return passthrough()
}
function sendToClient(client, message) {
return new Promise((resolve, reject) => {
const channel = new MessageChannel()
channel.port1.onmessage = (event) => {
if (event.data && event.data.error) {
return reject(event.data.error)
}
resolve(event.data)
}
client.postMessage(JSON.stringify(message), [channel.port2])
})
}
function sleep(timeMs) {
return new Promise((resolve) => {
setTimeout(resolve, timeMs)
})
}
async function respondWithMock(response) {
await sleep(response.delay)
return new Response(response.body, response)
}
function respondWithMockStream(operationChannel, mockResponse) {
let streamCtrl
const stream = new ReadableStream({
start: (controller) => (streamCtrl = controller),
})
return new Promise(async (resolve, reject) => {
operationChannel.onmessageerror = (event) => {
operationChannel.close()
return reject(event.data.error)
}
operationChannel.onmessage = (event) => {
if (!event.data) {
return
}
switch (event.data.type) {
case 'MOCK_RESPONSE_CHUNK': {
streamCtrl.enqueue(event.data.payload)
break
}
case 'MOCK_RESPONSE_END': {
streamCtrl.close()
operationChannel.close()
}
}
}
await sleep(mockResponse.delay)
return resolve(new Response(stream, mockResponse))
})
}