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Fetch JSON

Send a GET request and read in JSON from the response. Use to fetch external data.
export default {
async fetch(request, env, ctx) {
const url = "https://jsonplaceholder.typicode.com/todos/1";
// gatherResponse returns both content-type & response body as a string
async function gatherResponse(response) {
const { headers } = response;
const contentType = headers.get("content-type") || "";
if (contentType.includes("application/json")) {
return { contentType, result: JSON.stringify(await response.json()) };
}
return { contentType, result: response.text() };
}
const response = await fetch(url);
const { contentType, result } = await gatherResponse(response);
const options = { headers: { "content-type": contentType } };
return new Response(result, options);
},
};
interface Env {}
export default {
async fetch(request, env, ctx): Promise<Response> {
const url = "https://jsonplaceholder.typicode.com/todos/1";
// gatherResponse returns both content-type & response body as a string
async function gatherResponse(response) {
const { headers } = response;
const contentType = headers.get("content-type") || "";
if (contentType.includes("application/json")) {
return { contentType, result: JSON.stringify(await response.json()) };
}
return { contentType, result: response.text() };
}
const response = await fetch(url);
const { contentType, result } = await gatherResponse(response);
const options = { headers: { "content-type": contentType } };
return new Response(result, options);
},
} satisfies ExportedHandler<Env>;
from js import Response, fetch, Headers, JSON
async def on_fetch(request):
url = "https://jsonplaceholder.typicode.com/todos/1"
# gather_response returns both content-type & response body as a string
async def gather_response(response):
headers = response.headers
content_type = headers["content-type"] or ""
if "application/json" in content_type:
return (content_type, JSON.stringify(await response.json()))
return (content_type, await response.text())
response = await fetch(url)
content_type, result = await gather_response(response)
headers = Headers.new({"content-type": content_type}.items())
return Response.new(result, headers=headers)