Add validation for beforeSend hook to ensure required properties remain intact

- Validate that 'from' field is not removed
- Validate that 'to' field is not removed or emptied
- Validate that 'subject' field is not removed
- Validate that at least 'html' or 'text' content exists
- Throw clear error messages if validation fails
- Bump version to 0.1.21

dev/test-hook-validation.ts

@@ -0,0 +1,113 @@
+// Test hook validation in the dev environment
+import { getPayload } from 'payload'
+import config from './payload.config.js'
+
+async function testHookValidation() {
+  const payload = await getPayload({ config: await config })
+
+  console.log('\n🧪 Testing beforeSend hook validation...\n')
+
+  // Test 1: Create an email to process
+  const email = await payload.create({
+    collection: 'emails',
+    data: {
+      to: ['test@example.com'],
+      subject: 'Test Email for Validation',
+      html: '<p>Testing hook validation</p>',
+      text: 'Testing hook validation',
+      status: 'pending'
+    }
+  })
+
+  console.log('✅ Test email created:', email.id)
+
+  // Get the mailing service
+  const mailingService = (payload as any).mailing.service
+
+  // Test 2: Temporarily replace the config with a bad hook
+  const originalBeforeSend = mailingService.config.beforeSend
+
+  console.log('\n📝 Test: Hook that removes "from" field...')
+  mailingService.config.beforeSend = async (options: any, email: any) => {
+    delete options.from
+    return options
+  }
+
+  try {
+    await mailingService.processEmails()
+    console.log('❌ Should have thrown error for missing "from"')
+  } catch (error: any) {
+    if (error.message.includes('must not remove the "from" property')) {
+      console.log('✅ Correctly caught missing "from" field')
+    } else {
+      console.log('❌ Unexpected error:', error.message)
+    }
+  }
+
+  console.log('\n📝 Test: Hook that empties "to" array...')
+  mailingService.config.beforeSend = async (options: any, email: any) => {
+    options.to = []
+    return options
+  }
+
+  try {
+    await mailingService.processEmails()
+    console.log('❌ Should have thrown error for empty "to"')
+  } catch (error: any) {
+    if (error.message.includes('must not remove or empty the "to" property')) {
+      console.log('✅ Correctly caught empty "to" array')
+    } else {
+      console.log('❌ Unexpected error:', error.message)
+    }
+  }
+
+  console.log('\n📝 Test: Hook that removes "subject"...')
+  mailingService.config.beforeSend = async (options: any, email: any) => {
+    delete options.subject
+    return options
+  }
+
+  try {
+    await mailingService.processEmails()
+    console.log('❌ Should have thrown error for missing "subject"')
+  } catch (error: any) {
+    if (error.message.includes('must not remove the "subject" property')) {
+      console.log('✅ Correctly caught missing "subject" field')
+    } else {
+      console.log('❌ Unexpected error:', error.message)
+    }
+  }
+
+  console.log('\n📝 Test: Hook that removes both "html" and "text"...')
+  mailingService.config.beforeSend = async (options: any, email: any) => {
+    delete options.html
+    delete options.text
+    return options
+  }
+
+  try {
+    await mailingService.processEmails()
+    console.log('❌ Should have thrown error for missing content')
+  } catch (error: any) {
+    if (error.message.includes('must not remove both "html" and "text" properties')) {
+      console.log('✅ Correctly caught missing content fields')
+    } else {
+      console.log('❌ Unexpected error:', error.message)
+    }
+  }
+
+  // Restore original hook
+  mailingService.config.beforeSend = originalBeforeSend
+
+  console.log('\n✅ All validation tests completed!\n')
+
+  // Clean up
+  await payload.delete({
+    collection: 'emails',
+    id: email.id
+  })
+
+  process.exit(0)
+}
+
+testHookValidation().catch(console.error)