"use strict";
const express = require("express");
const fetch = require("node-fetch");
const { encode } = require("html-entities");
const cleanBaseURL = require("clean-base-url");
const path = require("path");
const fs = require("fs");
const fsPromises = fs.promises;
const { JSDOM } = require("jsdom");
const { shouldLoadPluginTestJs } = require("discourse-plugins");
const { Buffer } = require("node:buffer");
const { cwd, env } = require("node:process");
// via https://stackoverflow.com/a/6248722/165668
function generateUID() {
let firstPart = (Math.random() * 46656) | 0; // eslint-disable-line no-bitwise
let secondPart = (Math.random() * 46656) | 0; // eslint-disable-line no-bitwise
firstPart = ("000" + firstPart.toString(36)).slice(-3);
secondPart = ("000" + secondPart.toString(36)).slice(-3);
return firstPart + secondPart;
}
function htmlTag(buffer, bootstrap) {
let classList = "";
if (bootstrap.html_classes) {
classList = ` class="${bootstrap.html_classes}"`;
}
buffer.push(``);
}
function head(buffer, bootstrap, headers, baseURL) {
if (bootstrap.csrf_token) {
buffer.push(``);
buffer.push(``);
}
if (bootstrap.theme_id) {
buffer.push(
``
);
}
if (bootstrap.theme_color) {
buffer.push(``);
}
if (bootstrap.authentication_data) {
buffer.push(
``
);
}
let setupData = "";
Object.keys(bootstrap.setup_data).forEach((sd) => {
let val = bootstrap.setup_data[sd];
if (val) {
if (Array.isArray(val)) {
val = JSON.stringify(val);
} else {
val = val.toString();
}
setupData += ` data-${sd.replace(/\_/g, "-")}="${encode(val)}"`;
}
});
buffer.push(``);
if (bootstrap.preloaded.currentUser) {
const user = JSON.parse(bootstrap.preloaded.currentUser);
let { admin, staff } = user;
if (staff) {
buffer.push(``);
}
if (admin) {
buffer.push(``);
}
}
bootstrap.plugin_js.forEach((src) =>
buffer.push(``)
);
buffer.push(bootstrap.theme_html.translations);
buffer.push(bootstrap.theme_html.js);
buffer.push(bootstrap.theme_html.head_tag);
buffer.push(bootstrap.html.before_head_close);
}
function localeScript(buffer, bootstrap) {
buffer.push(``);
}
function beforeScriptLoad(buffer, bootstrap) {
buffer.push(bootstrap.html.before_script_load);
localeScript(buffer, bootstrap);
(bootstrap.extra_locales || []).forEach((l) =>
buffer.push(``)
);
}
function discoursePreloadStylesheets(buffer, bootstrap) {
(bootstrap.stylesheets || []).forEach((s) => {
let link = ``;
buffer.push(link);
});
}
function discourseStylesheets(buffer, bootstrap) {
(bootstrap.stylesheets || []).forEach((s) => {
let attrs = [];
if (s.media) {
attrs.push(`media="${s.media}"`);
}
if (s.target) {
attrs.push(`data-target="${s.target}"`);
}
if (s.theme_id) {
attrs.push(`data-theme-id="${s.theme_id}"`);
}
if (s.class) {
attrs.push(`class="${s.class}"`);
}
let link = ``;
buffer.push(link);
});
}
function body(buffer, bootstrap) {
buffer.push(bootstrap.theme_html.header);
buffer.push(bootstrap.html.header);
}
function bodyFooter(buffer, bootstrap, headers) {
buffer.push(bootstrap.theme_html.body_tag);
buffer.push(bootstrap.html.before_body_close);
let v = generateUID();
buffer.push(`
`);
}
function hiddenLoginForm(buffer, bootstrap) {
if (!bootstrap.preloaded.currentUser) {
buffer.push(`
`);
}
}
function preloaded(buffer, bootstrap) {
buffer.push(
``
);
}
const BUILDERS = {
"html-tag": htmlTag,
"before-script-load": beforeScriptLoad,
"discourse-preload-stylesheets": discoursePreloadStylesheets,
head,
body,
"discourse-stylesheets": discourseStylesheets,
"hidden-login-form": hiddenLoginForm,
preloaded,
"body-footer": bodyFooter,
"locale-script": localeScript,
};
function replaceIn(bootstrap, template, id, headers, baseURL) {
let buffer = [];
BUILDERS[id](buffer, bootstrap, headers, baseURL);
let contents = buffer.filter((b) => b && b.length > 0).join("\n");
return template.replace(``, contents);
}
function extractPreloadJson(html) {
const dom = new JSDOM(html);
const dataElement = dom.window.document.querySelector("#data-preloaded");
if (!dataElement || !dataElement.dataset) {
return;
}
return dataElement.dataset.preloaded;
}
async function applyBootstrap(bootstrap, template, response, baseURL, preload) {
bootstrap.preloaded = Object.assign(JSON.parse(preload), bootstrap.preloaded);
Object.keys(BUILDERS).forEach((id) => {
template = replaceIn(bootstrap, template, id, response.headers, baseURL);
});
return template;
}
async function buildFromBootstrap(proxy, baseURL, req, response, preload) {
try {
const template = await fsPromises.readFile(
path.join(cwd(), "dist", "index.html"),
"utf8"
);
let url = new URL(`${proxy}${baseURL}bootstrap.json`);
url.searchParams.append("for_url", req.url);
const forUrlSearchParams = new URL(req.url, "https://dummy-origin.invalid")
.searchParams;
const mobileView = forUrlSearchParams.get("mobile_view");
if (mobileView) {
url.searchParams.append("mobile_view", mobileView);
}
const reqUrlSafeMode = forUrlSearchParams.get("safe_mode");
if (reqUrlSafeMode) {
url.searchParams.append("safe_mode", reqUrlSafeMode);
}
const reqUrlPreviewThemeId = forUrlSearchParams.get("preview_theme_id");
if (reqUrlPreviewThemeId) {
url.searchParams.append("preview_theme_id", reqUrlPreviewThemeId);
}
const res = await fetch(url, { headers: req.headers });
const json = await res.json();
return applyBootstrap(json.bootstrap, template, response, baseURL, preload);
} catch (error) {
throw new Error(
`Could not get ${proxy}${baseURL}bootstrap.json\n\n${error}`
);
}
}
async function handleRequest(proxy, baseURL, req, res) {
// x-forwarded-host is used in e.g. GitHub CodeSpaces
let originalHost = req.headers["x-forwarded-host"] || req.headers.host;
if (env["FORWARD_HOST"] === "true") {
if (/^localhost(\:|$)/.test(originalHost)) {
// Can't access default site in multisite via "localhost", redirect to 127.0.0.1
res.redirect(
307,
`http://${originalHost.replace("localhost", "127.0.0.1")}${req.path}`
);
return;
} else {
req.headers.host = originalHost;
}
} else {
req.headers.host = new URL(proxy).host;
}
if (req.headers["Origin"]) {
req.headers["Origin"] = req.headers["Origin"]
.replace(req.headers.host, originalHost)
.replace(/^https/, "http");
}
if (req.headers["Referer"]) {
req.headers["Referer"] = req.headers["Referer"]
.replace(req.headers.host, originalHost)
.replace(/^https/, "http");
}
let url = `${proxy}${req.path}`;
const queryLoc = req.url.indexOf("?");
if (queryLoc !== -1) {
url += req.url.slice(queryLoc);
}
if (req.method === "GET") {
req.headers["X-Discourse-Ember-CLI"] = "true";
}
const response = await fetch(url, {
method: req.method,
body: /GET|HEAD/.test(req.method) ? null : req.body,
headers: req.headers,
redirect: "manual",
});
response.headers.forEach((value, header) => {
res.set(header, value);
});
res.set("content-encoding", null);
const location = response.headers.get("location");
if (location) {
const newLocation = location.replace(proxy, `http://${originalHost}`);
res.set("location", newLocation);
}
const csp = response.headers.get("content-security-policy");
if (csp) {
const emberCliAdditions = [
`http://${originalHost}/assets/`,
`http://${originalHost}/ember-cli-live-reload.js`,
`http://${originalHost}/_lr/`,
].join(" ");
const newCSP = csp
.replaceAll(proxy, `http://${originalHost}`)
.replaceAll("script-src ", `script-src ${emberCliAdditions} `);
res.set("content-security-policy", newCSP);
}
const contentType = response.headers.get("content-type");
const isHTML = contentType?.startsWith("text/html");
res.status(response.status);
if (isHTML) {
const responseText = await response.text();
const preloadJson = isHTML ? extractPreloadJson(responseText) : null;
if (preloadJson) {
const html = await buildFromBootstrap(
proxy,
baseURL,
req,
response,
extractPreloadJson(responseText)
);
res.set("content-type", "text/html");
res.send(html);
} else {
res.send(responseText);
}
} else {
res.send(Buffer.from(await response.arrayBuffer()));
}
}
module.exports = {
name: require("./package").name,
isDevelopingAddon() {
return true;
},
contentFor(type, config) {
if (shouldLoadPluginTestJs() && type === "test-plugin-js") {
const scripts = [];
const pluginInfos = this.app.project
.findAddonByName("discourse-plugins")
.pluginInfos();
for (const {
pluginName,
directoryName,
hasJs,
hasAdminJs,
} of pluginInfos) {
if (hasJs) {
scripts.push({
src: `plugins/${directoryName}.js`,
name: pluginName,
});
}
if (fs.existsSync(`../plugins/${directoryName}_extras.js.erb`)) {
scripts.push({
src: `plugins/${directoryName}_extras.js`,
name: pluginName,
});
}
if (hasAdminJs) {
scripts.push({
src: `plugins/${directoryName}_admin.js`,
name: pluginName,
});
}
}
return scripts
.map(
({ src, name }) =>
``
)
.join("\n");
} else if (shouldLoadPluginTestJs() && type === "test-plugin-tests-js") {
return this.app.project
.findAddonByName("discourse-plugins")
.pluginInfos()
.filter(({ hasTests }) => hasTests)
.map(
({ directoryName, pluginName }) =>
``
)
.join("\n");
} else if (shouldLoadPluginTestJs() && type === "test-plugin-css") {
return ``;
}
},
serverMiddleware(config) {
const app = config.app;
let { proxy, rootURL, baseURL } = config.options;
if (!proxy) {
// eslint-disable-next-line no-console
console.error(`
Discourse can't be run without a \`--proxy\` setting, because it needs a Rails application
to serve API requests. For example:
yarn run ember serve --proxy "http://localhost:3000"\n`);
throw "--proxy argument is required";
}
baseURL = rootURL === "" ? "/" : cleanBaseURL(rootURL || baseURL);
const rawMiddleware = express.raw({ type: () => true, limit: "100mb" });
app.use(
"/favicon.ico",
express.static(
path.join(
__dirname,
"../../../../../../public/images/discourse-logo-sketch-small.png"
)
)
);
app.use(rawMiddleware, async (req, res, next) => {
try {
if (this.shouldForwardRequest(req)) {
await handleRequest(proxy, baseURL, req, res);
} else {
// Fixes issues when using e.g. "localhost" instead of loopback IP address
req.headers.host = "127.0.0.1";
}
} catch (error) {
res.send(`
Discourse Ember CLI Proxy Error
${error.stack}
`);
} finally {
if (!res.headersSent) {
return next();
}
}
});
},
shouldForwardRequest(request) {
if (
[
"/tests/index.html",
"/ember-cli-live-reload.js",
"/testem.js",
"/assets/test-i18n.js",
].includes(request.path)
) {
return false;
}
if (request.path.startsWith("/_lr/")) {
return false;
}
return true;
},
};