webpack: Build a ZULIP_VERSION global constant into the built product.

.eslintrc.json

@@ -237,6 +237,9 @@
                 "browser": true,
                 "node": false
             },
+            "globals": {
+                "ZULIP_VERSION": false
+            },
             "rules": {
                 "no-console": "error"
             },

tools/webpack

@@ -3,11 +3,17 @@ import argparse
 import json
 import os
 import subprocess
+import sys
 from typing import NoReturn
 
+sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), "..")))
+
 os.chdir(os.path.join(os.path.dirname(__file__), "../web"))
 
 
+from version import ZULIP_VERSION
+
+
 def build_for_prod_or_puppeteer(quiet: bool) -> NoReturn:
     """Builds for production, writing the output to disk"""
 
@@ -15,7 +21,11 @@ def build_for_prod_or_puppeteer(quiet: bool) -> NoReturn:
     with open("/proc/meminfo") as meminfo:
         if int(next(meminfo).split()[1]) < 3 * 1024 * 1024:
             webpack_args += ["--max-old-space-size=1536"]
-    webpack_args += ["../node_modules/.bin/webpack-cli", "--mode=production"]
+    webpack_args += [
+        "../node_modules/.bin/webpack-cli",
+        "--mode=production",
+        f"--env=ZULIP_VERSION={ZULIP_VERSION}",
+    ]
     if quiet:
         webpack_args += ["--stats=errors-only"]
     os.execvp(webpack_args[0], webpack_args)

web/src/global.d.ts

@@ -9,3 +9,5 @@ interface JQuery {
     expectOne(): JQuery;
     tab(action?: string): this; // From web/third/bootstrap
 }
+
+declare const ZULIP_VERSION: string;

web/webpack.config.ts

@@ -5,6 +5,7 @@ import path from "path";
 import CssMinimizerPlugin from "css-minimizer-webpack-plugin";
 import HtmlWebpackPlugin from "html-webpack-plugin";
 import MiniCssExtractPlugin from "mini-css-extract-plugin";
+import {DefinePlugin} from "webpack";
 import type webpack from "webpack";
 import BundleTracker from "webpack-bundle-tracker";
 
@@ -12,7 +13,10 @@ import DebugRequirePlugin from "./debug-require-webpack-plugin";
 import assets from "./webpack.assets.json";
 import dev_assets from "./webpack.dev-assets.json";
 
-export default (env: {minimize?: boolean} = {}, argv: {mode?: string}): webpack.Configuration[] => {
+export default (
+    env: {minimize?: boolean; ZULIP_VERSION?: string} = {},
+    argv: {mode?: string},
+): webpack.Configuration[] => {
     const production: boolean = argv.mode === "production";
 
     const baseConfig: webpack.Configuration = {
@@ -194,6 +198,9 @@ export default (env: {minimize?: boolean} = {}, argv: {mode?: string}): webpack.
             },
         },
         plugins: [
+            new DefinePlugin({
+                ZULIP_VERSION: JSON.stringify(env.ZULIP_VERSION || "development"),
+            }),
             new DebugRequirePlugin(),
             new BundleTracker({
                 filename: production