core: support hydrooj patch

packages/hydrooj/bin/commands.ts

@@ -204,6 +204,7 @@ if (!argv.args[0] || argv.args[0] === 'cli') {
         fs.removeSync(newAddonPath);
         console.log(`Successfully uninstalled ${name}.`);
     });
+    require('../src/commands/patch').register(cli);
     cli.help();
     cli.parse();
     if (!cli.matchedCommand) {

packages/hydrooj/src/commands/patch.ts

@@ -0,0 +1,31 @@
+import child from 'child_process';
+import { CAC } from 'cac';
+import fs from 'fs-extra';
+import superagent from 'superagent';
+import { Logger } from '@hydrooj/utils';
+
+const logger = new Logger('patch');
+
+export function register(cli: CAC) {
+    cli.command('patch <module> <patch>').action(async (filename, patch) => {
+        const mod = require.resolve(filename);
+        if (!mod) {
+            logger.error('Module %s not found', filename);
+            return;
+        }
+        logger.info('Patching %s', mod);
+        const res = await superagent.get(patch);
+        logger.info('Downloaded patch');
+        for (let i = 0; i <= 100; i++) {
+            const fp = `${mod}.${i}.patch`;
+            if (fs.existsSync(fp)) continue;
+            patch = fp;
+            break;
+        }
+        await fs.writeFile(patch, res.text);
+        child.execSync(`patch ${mod} -o ${mod} < ${patch}`);
+        logger.info('Patched %s', mod);
+    });
+
+    // TODO: support revert patch
+}