errorlog

src/util/errorLog.js

@@ -0,0 +1,55 @@
+import { appendFileSync, mkdirSync } from 'fs';
+import { dirname, resolve } from 'path';
+import { fileURLToPath } from 'url';
+import { prettyJson } from '../util/prettyJson.js';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const LOG_DIR = process.env.ERROR_LOG_DIR || resolve(__dirname, '../../logs/errors');
+const LOG_PREFIX = 'error-';
+
+let dirEnsured = false;
+
+function ensureLogDir() {
+    if (dirEnsured) return;
+    mkdirSync(LOG_DIR, { recursive: true });
+    dirEnsured = true;
+}
+
+/**
+ * Writes a plain-text error log file (no ANSI colors) to the error log
+ * directory and returns the file path. Never throws.
+ * @param {string} label Short description, e.g. "POST /api/delivery 500"
+ * @param {Record<string, unknown>} sections Named sections (request, body, response, error…)
+ * @returns {string | null} Path of the log file, or null on failure
+ */
+export function writeErrorLog(label, sections) {
+    try {
+        ensureLogDir();
+        const stamp = new Date().toISOString().replace(/[:.]/g, '-');
+        const safeLabel = label
+            .toLowerCase()
+            .replace(/[^a-z0-9]+/g, '-')
+            .replace(/^-+|-+$/g, '')
+            .slice(0, 40);
+        const filePath = resolve(LOG_DIR, `${LOG_PREFIX}${stamp}-${safeLabel}.log`);
+        const divider = '='.repeat(80);
+
+        const parts = [
+            `Timestamp: ${new Date().toISOString()}`,
+            `Label:     ${label}`,
+            divider,
+        ];
+
+        for (const [name, value] of Object.entries(sections)) {
+            parts.push(`--- ${name} ${'-'.repeat(Math.max(0, 74 - name.length))}`);
+            parts.push(prettyJson(value, { colors: false }));
+        }
+
+        appendFileSync(filePath, `${parts.join('\n')}\n`);
+        console.error(`[error-log] Wrote ${filePath}`);
+        return filePath;
+    } catch (err) {
+        console.error('[error-log] Failed to write error log:', err.message);
+        return null;
+    }
+}