Skip to content

fix: buffer multi-segment HTTP POST/PUT bodies in fetch network adapter #1567

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
muralidhar-challa wants to merge 3 commits into from
+443 −101
Closed

fix: buffer multi-segment HTTP POST/PUT bodies in fetch network adapter #1567

Changes from 1 commit
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
165cfc2
fix: buffer multi-segment HTTP POST/PUT bodies in fetch network adapter
muralidhar-challa May 23, 2026
2e022cd
fix: binary-safe HTTP body buffering for multi-segment POST/PUT
muralidhar-challa May 25, 2026
d4a8dd4
test: add integration test for multi-segment POST body buffering
muralidhar-challa May 26, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
130 changes: 87 additions & 43 deletions src/browser/fetch_network.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -74,6 +74,23 @@ FetchNetworkAdapter.prototype.tcp_probe = function(port)
*/
async function on_data_http(data)
{
// If we're buffering a partial request body, accumulate chunks until
// Content-Length is satisfied, then fire the deferred fetch.
if(this._xb) {
const chunk = data instanceof Uint8Array ? data : new Uint8Array(data);
const combined = new Uint8Array(this._xb.buf.length + chunk.length);
combined.set(this._xb.buf);
combined.set(chunk, this._xb.buf.length);
this._xb.buf = combined;
if(this._xb.buf.length >= this._xb.cl) {
const body = new TextDecoder().decode(this._xb.buf);
const done = this._xb.done;
this._xb = null;
done(body);
}
return;
}

this.read = this.read || "";
this.read += new TextDecoder().decode(data);
if(this.read && this.read.indexOf("\r\n\r\n") !== -1) {
Expand Down Expand Up @@ -129,57 +146,84 @@ async function on_data_http(data)
headers: req_headers,
};
if(["put", "post"].indexOf(opts.method.toLowerCase()) !== -1) {
// Check if the body might be split across multiple TCP segments.
// If Content-Length is present and larger than what we have,
// buffer and wait for the remaining chunks.
const content_length = parseInt(req_headers.get("content-length") || "0", 10);
const body_bytes = (data instanceof Uint8Array) ? data : new TextEncoder().encode(data);
if(content_length > 0 && body_bytes.length < content_length) {
const fetch_url = this.net.cors_proxy ? this.net.cors_proxy + encodeURIComponent(target.href) : target.href;
Copy link
Copy Markdown
Contributor

@SuperMaxusa SuperMaxusa May 24, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Isn't this repeated in FetchNetworkAdapter.prototype.fetch (see line 230)? Same on line 169.

this._xb = {
buf: body_bytes,
cl: content_length,
done: (body) => {
opts.body = body;
this._dispatch_fetch(fetch_url, opts);
},
};
return;
}
opts.body = data;
}

const fetch_url = this.net.cors_proxy ? this.net.cors_proxy + encodeURIComponent(target.href) : target.href;
const encoder = new TextEncoder();
let response_started = false;
let handler = (resp) => {
let resp_headers = new Headers(resp.headers);
resp_headers.delete("content-encoding");
resp_headers.delete("keep-alive");
resp_headers.delete("content-length");
resp_headers.delete("transfer-encoding");
resp_headers.set("x-was-fetch-redirected", `${!!resp.redirected}`);
resp_headers.set("x-fetch-resp-url", resp.url);
resp_headers.set("connection", "close");
this._dispatch_fetch(fetch_url, opts);
}
}

this.write(this.net.form_response_head(resp.status, resp.statusText, resp_headers));
response_started = true;
/**
* @this {TCPConnection}
* @param {string} fetch_url
* @param {!Object} opts
*/
FetchNetworkAdapter.prototype._dispatch_fetch = function(fetch_url, opts)
{
const encoder = new TextEncoder();
let response_started = false;
let handler = (resp) => {
let resp_headers = new Headers(resp.headers);
resp_headers.delete("content-encoding");
resp_headers.delete("keep-alive");
resp_headers.delete("content-length");
resp_headers.delete("transfer-encoding");
resp_headers.set("x-was-fetch-redirected", `${!!resp.redirected}`);
resp_headers.set("x-fetch-resp-url", resp.url);
resp_headers.set("connection", "close");

if(resp.body && resp.body.getReader) {
const resp_reader = resp.body.getReader();
const pump = ({ value, done }) => {
if(value) {
this.write(value);
}
if(done) {
this.close();
}
else {
return resp_reader.read().then(pump);
}
};
resp_reader.read().then(pump);
} else {
resp.arrayBuffer().then(buffer => {
this.write(new Uint8Array(buffer));
this.write(this.net.form_response_head(resp.status, resp.statusText, resp_headers));
response_started = true;

if(resp.body && resp.body.getReader) {
const resp_reader = resp.body.getReader();
const pump = ({ value, done }) => {
if(value) {
this.write(value);
}
if(done) {
this.close();
});
}
};
}
else {
return resp_reader.read().then(pump);
}
};
resp_reader.read().then(pump);
} else {
resp.arrayBuffer().then(buffer => {
this.write(new Uint8Array(buffer));
this.close();
});
}
};

this.net.fetch(fetch_url, opts).then(handler)
.catch((e) => {
console.warn("Fetch Failed: " + fetch_url + "\n" + e);
if(!response_started) {
this.net.respond_text_and_close(this, 502, "Fetch Error", `Fetch ${fetch_url} failed:\n\n${e.stack || e.message}`);
}
this.close();
});
}
}
this.net.fetch(fetch_url, opts).then(handler)
.catch((e) => {
console.warn("Fetch Failed: " + fetch_url + "\n" + e);
if(!response_started) {
this.net.respond_text_and_close(this, 502, "Fetch Error", `Fetch ${fetch_url} failed:\n\n${e.stack || e.message}`);
}
this.close();
});
};

FetchNetworkAdapter.prototype.fetch = async function(url, options)
{
Expand Down