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Aggregate requests

Send two GET request to two urls and aggregates the responses into one response.
export default {
async fetch(request) {
/**
* someHost is set up to return JSON responses
* Replace url1 and url2 with the hosts you wish to send requests to
* @param {string} url the URL to send the request to
*/
const someHost = 'https://examples.cloudflareworkers.com/demos';
const url1 = someHost + '/requests/json';
const url2 = someHost + '/requests/json';
const type = 'application/json;charset=UTF-8';
/**
* gatherResponse awaits and returns a response body as a string.
* Use await gatherResponse(..) in an async function to get the response body
* @param {Response} response
*/
async function gatherResponse(response) {
const { headers } = response;
const contentType = headers.get('content-type') || '';
if (contentType.includes('application/json')) {
return JSON.stringify(await response.json());
} else if (contentType.includes('application/text')) {
return response.text();
} else if (contentType.includes('text/html')) {
return response.text();
} else {
return response.text();
}
}
const init = {
headers: {
'content-type': type,
},
};
const responses = await Promise.all([fetch(url1, init), fetch(url2, init)]);
const results = await Promise.all([
gatherResponse(responses[0]),
gatherResponse(responses[1]),
]);
return new Response(results.join(), init);
},
};
/**
* someHost is set up to return JSON responses
* Replace url1 and url2 with the hosts you wish to send requests to
* @param {string} url the URL to send the request to
*/
const someHost = 'https://examples.cloudflareworkers.com/demos';
const url1 = someHost + '/requests/json';
const url2 = someHost + '/requests/json';
const type = 'application/json;charset=UTF-8';
/**
* gatherResponse awaits and returns a response body as a string.
* Use await gatherResponse(..) in an async function to get the response body
* @param {Response} response
*/
async function gatherResponse(response) {
const { headers } = response;
const contentType = headers.get('content-type') || '';
if (contentType.includes('application/json')) {
return JSON.stringify(await response.json());
} else if (contentType.includes('application/text')) {
return response.text();
} else if (contentType.includes('text/html')) {
return response.text();
} else {
return response.text();
}
}
async function handleRequest() {
const init = {
headers: {
'content-type': type,
},
};
const responses = await Promise.all([fetch(url1, init), fetch(url2, init)]);
const results = await Promise.all([gatherResponse(responses[0]), gatherResponse(responses[1])]);
return new Response(results.join(), init);
}
addEventListener('fetch', event => {
return event.respondWith(handleRequest());
});