Cloudflare Docs
Workers
Edit this page
Report an issue with this page
Log into the Cloudflare dashboard
Set theme to dark (⇧+D)

Service bindings — HTTP

Worker A that declares a Service binding to Worker B can forward a Request object to Worker B, by calling the fetch() method that is exposed on the binding object.

For example, consider the following Worker that implements a fetch() handler:

name = "worker_b"
main = "./src/workerB.js"
// For Wrangler to read a JSON configuration file, you must add the `-j` flag
// e.g. `wrangler -j dev`
{
"name": "worker_b",
"main": "./src/workerB.js"
}
src/workerB.js
export default {
async fetch(request, env, ctx) {
return new Response("Hello World!");
}
}

The following Worker declares a binding to the Worker above:

name = "worker_a"
main = "./src/workerA.js"
services = [
{ binding = "WORKER_B", service = "worker_b" }
]
// For Wrangler to read a JSON configuration file, you must add the `-j` flag
// e.g. `wrangler -j dev`
{
"name": "worker_a",
"main": "./src/workerA.js",
"services": [
{
"binding": "WORKER_B",
"service": "worker_b"
}
]
}

And then can forward a request to it:

src/workerA.js
export default {
async fetch(request, env) {
return await env.WORKER_B.fetch(request);
},
};