refactor: E2E tests use real email() handler (#870)

* refactor: add receive_mail E2E endpoint using real email() handler

Add /admin/test/receive_mail that constructs a mock ForwardableEmailMessage
and calls the real email() handler, so E2E tests exercise the full mail
processing pipeline. Extract both test endpoints into e2e_test_api.ts.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* chore: trigger CI

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

worker/src/admin_api/e2e_test_api.ts

@@ -0,0 +1,63 @@
+import { Context } from 'hono'
+import { getBooleanValue } from '../utils'
+
+// Direct DB insert — bypasses the email() handler.
+const seedMail = async (c: Context<HonoCustomType>) => {
+    if (!getBooleanValue(c.env.E2E_TEST_MODE)) {
+        return c.text("Not available", 404);
+    }
+    const { address, source, raw, message_id } = await c.req.json();
+    if (!address || !raw) {
+        return c.text("address and raw are required", 400);
+    }
+    if (raw.length > 1_000_000) {
+        return c.text("raw content too large", 400);
+    }
+    if (message_id && message_id.length > 255) {
+        return c.text("message_id too long", 400);
+    }
+    const msgId = message_id || `<e2e-${Date.now()}@test>`;
+    const { success } = await c.env.DB.prepare(
+        `INSERT INTO raw_mails (message_id, source, address, raw, created_at)`
+        + ` VALUES (?, ?, ?, ?, datetime('now'))`
+    ).bind(msgId, source || address, address, raw).run();
+    return c.json({ success });
+};
+
+// Exercises the real email() handler with a mock ForwardableEmailMessage.
+const receiveMail = async (c: Context<HonoCustomType>) => {
+    if (!getBooleanValue(c.env.E2E_TEST_MODE)) {
+        return c.text("Not available", 404);
+    }
+    const { from, to, raw } = await c.req.json();
+    if (!from || !to || !raw) {
+        return c.text("from, to and raw are required", 400);
+    }
+
+    // Parse MIME headers (unfold continuation lines, extract key:value pairs)
+    const headerSection = raw.substring(0, Math.max(0, raw.indexOf('\r\n\r\n')));
+    const headers = new Headers();
+    for (const line of headerSection.replace(/\r\n(?=[ \t])/g, ' ').split('\r\n')) {
+        const idx = line.indexOf(':');
+        if (idx > 0) headers.append(line.substring(0, idx).trim(), line.substring(idx + 1).trim());
+    }
+    if (!headers.has('Message-ID')) headers.set('Message-ID', `<e2e-${Date.now()}@test>`);
+
+    const rawBytes = new TextEncoder().encode(raw);
+    let rejected: string | undefined;
+    const mockMessage: ForwardableEmailMessage = {
+        from, to, headers,
+        rawSize: rawBytes.byteLength,
+        raw: new ReadableStream({ start(ctrl) { ctrl.enqueue(rawBytes); ctrl.close(); } }),
+        setReject(reason: string) { rejected = reason; },
+        forward: async () => ({ messageId: '' }),
+        reply: async () => ({ messageId: '' }),
+    };
+
+    const { email: emailHandler } = await import('../email');
+    await emailHandler(mockMessage, c.env, { waitUntil: () => {}, passThroughOnException: () => {} });
+
+    return c.json({ success: !rejected, ...(rejected ? { rejected } : {}) });
+};
+
+export default { seedMail, receiveMail };

worker/src/admin_api/index.ts

@@ -17,6 +17,7 @@ import db_api from './db_api'
 import ip_blacklist_settings from './ip_blacklist_settings'
 import ai_extract_settings from './ai_extract_settings'
 import { EmailRuleSettings } from '../models'
+import e2e_test_api from './e2e_test_api'
 
 export const api = new Hono<HonoCustomType>()
 
@@ -389,25 +390,6 @@ api.post("/admin/ip_blacklist/settings", ip_blacklist_settings.saveIpBlacklistSe
 api.get("/admin/ai_extract/settings", ai_extract_settings.getAiExtractSettings);
 api.post("/admin/ai_extract/settings", ai_extract_settings.saveAiExtractSettings);
 
-// Test-only endpoint for seeding emails. MUST NOT be enabled in production.
-api.post('/admin/test/seed_mail', async (c) => {
-    if (!getBooleanValue(c.env.E2E_TEST_MODE)) {
-        return c.text("Not available", 404);
-    }
-    const { address, source, raw, message_id } = await c.req.json();
-    if (!address || !raw) {
-        return c.text("address and raw are required", 400);
-    }
-    if (raw.length > 1_000_000) {
-        return c.text("raw content too large", 400);
-    }
-    if (message_id && message_id.length > 255) {
-        return c.text("message_id too long", 400);
-    }
-    const msgId = message_id || `<e2e-${Date.now()}@test>`;
-    const { success } = await c.env.DB.prepare(
-        `INSERT INTO raw_mails (message_id, source, address, raw, created_at)`
-        + ` VALUES (?, ?, ?, ?, datetime('now'))`
-    ).bind(msgId, source || address, address, raw).run();
-    return c.json({ success });
-});
+// E2E test endpoints
+api.post('/admin/test/seed_mail', e2e_test_api.seedMail);
+api.post('/admin/test/receive_mail', e2e_test_api.receiveMail);