web: add prerendered version.json endpoint for frontend metadata

web/package-lock.json

@@ -21,6 +21,7 @@
                 "@sveltejs/kit": "^2.0.0",
                 "@sveltejs/vite-plugin-svelte": "^3.0.0",
                 "@types/eslint__js": "^8.42.3",
+                "@types/node": "^20.14.10",
                 "eslint": "^8.57.0",
                 "svelte": "^4.2.7",
                 "svelte-check": "^3.6.0",
@@ -973,6 +974,15 @@
             "dev": true,
             "license": "MIT"
         },
+        "node_modules/@types/node": {
+            "version": "20.14.10",
+            "resolved": "https://registry.npmjs.org/@types/node/-/node-20.14.10.tgz",
+            "integrity": "sha512-MdiXf+nDuMvY0gJKxyfZ7/6UFsETO7mGKF54MVD/ekJS6HdFtpZFBgrh6Pseu64XTb2MLyFPlbW6hj8HYRQNOQ==",
+            "dev": true,
+            "dependencies": {
+                "undici-types": "~5.26.4"
+            }
+        },
         "node_modules/@types/pug": {
             "version": "2.0.10",
             "resolved": "https://registry.npmjs.org/@types/pug/-/pug-2.0.10.tgz",
@@ -3167,6 +3177,12 @@
                 }
             }
         },
+        "node_modules/undici-types": {
+            "version": "5.26.5",
+            "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-5.26.5.tgz",
+            "integrity": "sha512-JlCMO+ehdEIKqlFxk6IfVoAUVmgz7cU7zD/h9XZ0qzeosSHmUJVOzSQvvYSYWXkFXC+IfLKSIffhv0sVZup6pA==",
+            "dev": true
+        },
         "node_modules/uri-js": {
             "version": "4.4.1",
             "resolved": "https://registry.npmjs.org/uri-js/-/uri-js-4.4.1.tgz",

web/package.json

@@ -29,6 +29,7 @@
         "@sveltejs/kit": "^2.0.0",
         "@sveltejs/vite-plugin-svelte": "^3.0.0",
         "@types/eslint__js": "^8.42.3",
+        "@types/node": "^20.14.10",
         "eslint": "^8.57.0",
         "svelte": "^4.2.7",
         "svelte-check": "^3.6.0",

web/src/routes/version.json/+server.ts

@@ -0,0 +1,58 @@
+import { error, json } from '@sveltejs/kit';
+import { readFile }    from 'node:fs/promises';
+import { join, parse } from 'node:path';
+import { existsSync }  from 'node:fs';
+import { cwd }         from 'node:process';
+
+const findFile = (file: string) => {
+    let dir = cwd();
+
+    while (dir !== parse(dir).root) {
+        if (existsSync(join(dir, file))) {
+            return dir;
+        }
+
+        dir = join(dir, '../');
+    }
+}
+
+const root = findFile('.git');
+const pack = findFile('package.json');
+
+export async function GET() {
+    if (!root) {
+        return error(500, 'no git repository root found');
+    } else if (!pack) {
+        return error(500, 'no package root found');
+    }
+
+    const readGit = (filename: string) => readFile(join(root, filename), 'utf8');
+
+    const commit = (await readGit('.git/logs/HEAD'))
+                    ?.split('\n')
+                    ?.filter(String)
+                    ?.pop()
+                    ?.split(' ')[1];
+
+    const branch = (await readGit('.git/HEAD'))
+                    ?.replace(/^ref: refs\/heads\//, '')
+                    ?.trim();
+
+    const remote = (await readGit('.git/config'))
+                    ?.split('\n')
+                    ?.find(line => line.includes('url = ') && line.endsWith('.git'))
+                    ?.split(':')[1]
+                    ?.replace(/\.git$/, '');
+
+    const { version } = JSON.parse(
+        await readFile(join(pack, 'package.json'), 'utf8')
+    );
+
+    if (!commit || !branch || !remote || !version) {
+        return error(500, 'failed to extract project metadata');
+    }
+
+    return json({ commit, branch, remote, version });
+}
+
+export const prerender = true;