uWebSockets-graphql+jit.js

"use strict";

const { parse } = require("graphql");
const { compileQuery } = require("graphql-jit");
const uws = require("uWebSockets.js");
const { createApolloSchema } = require("../lib/schemas/createApolloSchema");

const cache = {};

const schema = createApolloSchema();

uws
  .App()
  .post("/graphql", (res) => {
    readJson(
      res,
      (body) => {
        const { query } = body;
        let compiled = cache[query];
        if (!compiled) {
          const document = parse(query);
          compiled = cache[query] = compileQuery(schema, document);
        }
        const ans = compiled.query({}, {}, {});
        res.end(JSON.stringify(ans));
      },
      () => {},
    );
  })
  .listen(4001, () => {});

function readJson(res, cb, err) {
  let buffer;
  /* Register data cb */
  res.onData((ab, isLast) => {
    let chunk = Buffer.from(ab);
    if (isLast) {
      let json;
      if (buffer) {
        try {
          json = JSON.parse(Buffer.concat([buffer, chunk]));
        } catch (e) {
          /* res.close calls onAborted */
          res.close();
          return;
        }
        cb(json);
      } else {
        try {
          json = JSON.parse(chunk);
        } catch (e) {
          /* res.close calls onAborted */
          res.close();
          return;
        }
        cb(json);
      }
    } else {
      if (buffer) {
        buffer = Buffer.concat([buffer, chunk]);
      } else {
        buffer = Buffer.concat([chunk]);
      }
    }
  });

  /* Register error cb */
  res.onAborted(err);
}