implement basic JSON parsing

.vscode/settings.json

@@ -0,0 +1,3 @@
+{
+  "editor.formatOnSave": true
+}

example/index.ts

@@ -1,3 +1,17 @@
-import { foo } from "../src/utils";
+import { endpoint } from "../src";
+import { startServer } from "../src/core/server";
 
-console.log(foo());
+type Data = {
+  name: string;
+};
+
+startServer(
+  endpoint<void, Data>(async (req) => {
+    return {
+      status: 200,
+      body: {
+        name: "foo",
+      },
+    };
+  }),
+);

package.json

@@ -13,5 +13,8 @@
   "devDependencies": {
     "@types/node": "^17.0.35",
     "esbuild": "^0.14.39"
+  },
+  "dependencies": {
+    "tslog": "^3.3.3"
   }
 }

src/compose.ts

@@ -0,0 +1 @@
+export type Server<Request, Response> = (request: Request) => Promise<Response>;

src/core/bufferedServer.ts

@@ -0,0 +1,52 @@
+import { Logger } from "tslog";
+import type { Server } from "../compose";
+import type { CoreRequest } from "./server";
+
+export type Request = Omit<CoreRequest, "response">;
+
+export type BufferedResponse = {
+  status: number;
+  body: string;
+};
+
+export function bufferedResponse(
+  app: Server<Request, BufferedResponse>,
+): Server<CoreRequest, void> {
+  return async function bufferedResp(request) {
+    const out = await app(request);
+    request.response.statusCode = out.status;
+    request.response.write(out.body);
+  };
+}
+
+export type BufferedRequest = Request & {
+  body: string;
+};
+
+export function bufferedRequest<Response>(
+  app: Server<BufferedRequest, Response>,
+): Server<Request, Response> {
+  return function bufferedReq(request) {
+    const logger = new Logger();
+    let body = "";
+    const response = new Promise<Response>((resolve) => {
+      request.request.on("data", (chunk) => {
+        body += chunk.toString();
+      });
+      request.request.on("end", () => {
+        app({
+          ...request,
+          body,
+        })
+          .then((out) => {
+            resolve(out);
+          })
+          .catch((err) => {
+            logger.error("App did not return a response", err);
+            resolve(undefined);
+          });
+      });
+    });
+    return response;
+  };
+}

src/core/server.ts

@@ -0,0 +1,48 @@
+import { createServer } from "http";
+import type { IncomingMessage, ServerResponse } from "http";
+import { Logger } from "tslog";
+import { Server } from "../compose";
+
+/** A basic request. */
+export type CoreRequest = {
+  /** The full URL for the request. */
+  url: string;
+  /** The HTTP method for the request. */
+  method: string;
+  /** The headers associated with the request. */
+  headers: { [key: string]: string | string[] };
+  /** The request body. */
+  request: IncomingMessage;
+  /** The response. */
+  response: ServerResponse;
+};
+
+export function startServer(app: Server<CoreRequest, void>) {
+  const logger = new Logger();
+  const server = createServer((req, res) => {
+    logger.info(req.method, req.url);
+    app({
+      url: req.url,
+      method: req.method,
+      headers: req.headers,
+      request: req,
+      response: res,
+    })
+      .then(() => {
+        logger.debug("request processed successfully");
+      })
+      .catch((error) => {
+        res.statusCode = 500;
+        logger.error("server throw an unexpected error", error);
+        res.write("Error!\n");
+        res.write(JSON.stringify(error));
+      })
+      .finally(() => {
+        res.end();
+      });
+  });
+  server.on("clientError", (err, socket) => {
+    socket.end("HTTP/1.1 400 Bad CoreRequest\r\n\r\n");
+  });
+  server.listen(8000);
+}

src/index.ts

@@ -1,9 +1,10 @@
-import http from "http";
+import type { Server } from "./compose";
+import { bufferedRequest, bufferedResponse } from "./core/bufferedServer";
+import type { CoreRequest } from "./core/server";
+import { jsonRequest, JSONRequest, jsonResponse, JSONResponse } from "./json";
 
-const server = http.createServer((req, res) => {
-  res.end();
-});
-server.on('clientError', (err, socket) => {
-  socket.end('HTTP/1.1 400 Bad Request\r\n\r\n');
-});
-server.listen(8000);
+export function endpoint<ReqData, RespData>(
+  app: Server<JSONRequest<ReqData>, JSONResponse<RespData>>,
+): Server<CoreRequest, void> {
+  return bufferedResponse(bufferedRequest(jsonResponse(jsonRequest(app))));
+}

src/json.ts

@@ -0,0 +1,32 @@
+import { Server } from "./compose";
+import type { BufferedRequest, BufferedResponse } from "./core/bufferedServer";
+
+export type JSONRequest<Data> = Omit<BufferedRequest, "body"> & { body: Data };
+
+export type JSONResponse<Data> = Omit<BufferedResponse, "body"> & {
+  body: Data;
+};
+
+export function jsonResponse<Request, Data>(
+  app: Server<Request, JSONResponse<Data>>,
+): Server<Request, BufferedResponse> {
+  return async function jsonResp(request) {
+    const out = await app(request);
+    return {
+      ...out,
+      body: JSON.stringify(out.body),
+    };
+  };
+}
+
+export function jsonRequest<Response, Data>(
+  app: Server<JSONRequest<Data | undefined>, Response>,
+): Server<BufferedRequest, Response> {
+  return async function jsonReq(request) {
+    let body: any | undefined;
+    if (request.body.length > 0) {
+      body = JSON.parse(request.body);
+    }
+    return app({ ...request, body });
+  };
+}

src/utils.ts

@@ -1,7 +0,0 @@
-export function foo() {
-  return "bar";
-}
-
-export function baz() {
-  return "baz";
-}

yarn.lock

@@ -7,6 +7,11 @@
   resolved "https://registry.npmjs.org/@types/node/-/node-17.0.35.tgz"
   integrity sha512-vu1SrqBjbbZ3J6vwY17jBs8Sr/BKA+/a/WtjRG+whKg1iuLFOosq872EXS0eXWILdO36DHQQeku/ZcL6hz2fpg==
 
+buffer-from@^1.0.0:
+  version "1.1.2"
+  resolved "https://registry.npmjs.org/buffer-from/-/buffer-from-1.1.2.tgz#2b146a6fd72e80b4f55d255f35ed59a3a9a41bd5"
+  integrity sha512-E+XQCRwSbaaiChtv6k6Dwgc+bx+Bs6vuKJHHl5kox/BaKbhiXzqQOwK4cO22yElGp2OCmjwVhT3HmxgyPGnJfQ==
+
 esbuild-android-64@0.14.39:
   version "0.14.39"
   resolved "https://registry.npmjs.org/esbuild-android-64/-/esbuild-android-64-0.14.39.tgz#09f12a372eed9743fd77ff6d889ac14f7b340c21"
@@ -132,3 +137,23 @@ esbuild@^0.14.39:
     esbuild-windows-32 "0.14.39"
     esbuild-windows-64 "0.14.39"
     esbuild-windows-arm64 "0.14.39"
+
+source-map-support@^0.5.21:
+  version "0.5.21"
+  resolved "https://registry.npmjs.org/source-map-support/-/source-map-support-0.5.21.tgz#04fe7c7f9e1ed2d662233c28cb2b35b9f63f6e4f"
+  integrity sha512-uBHU3L3czsIyYXKX88fdrGovxdSCoTGDRZ6SYXtSRxLZUzHg5P/66Ht6uoUlHu9EZod+inXhKo3qQgwXUT/y1w==
+  dependencies:
+    buffer-from "^1.0.0"
+    source-map "^0.6.0"
+
+source-map@^0.6.0:
+  version "0.6.1"
+  resolved "https://registry.npmjs.org/source-map/-/source-map-0.6.1.tgz#74722af32e9614e9c287a8d0bbde48b5e2f1a263"
+  integrity sha512-UjgapumWlbMhkBgzT7Ykc5YXUT46F0iKu8SGXq0bcwP5dz/h0Plj6enJqjz1Zbq2l5WaqYnrVbwWOWMyF3F47g==
+
+tslog@^3.3.3:
+  version "3.3.3"
+  resolved "https://registry.npmjs.org/tslog/-/tslog-3.3.3.tgz#751a469e0d36841bd7e03676c27e53e7ffe9bc3d"
+  integrity sha512-lGrkndwpAohZ9ntQpT+xtUw5k9YFV1DjsksiWQlBSf82TTqsSAWBARPRD9juI730r8o3Awpkjp2aXy9k+6vr+g==
+  dependencies:
+    source-map-support "^0.5.21"