feat: parse header to get resulting objects

README.md

@@ -94,7 +94,19 @@ authenticateMessage(message, authservId, ip, mailFrom, helo)
 })();
 ```
 
-The value of `result` is an String with the new Authentication-Results header to add to the top of the message headers.
+The value of `result` is an Object with properties `header` (String), and Objects for `spf`, `dkim`, `arc`, and `dmarc`.  These Object's contain a `result` (String) and conditionally a `reason` (String) value.
+
+An example `result` object is provided below:
+
+```js
+{
+  header: 'Authentication-Results: example.com; spf=none smtp.helo=domain.of.sender.net smtp.mailfrom=test.com; dkim=pass header.d=forwardemail.net; arc=pass; dmarc=fail (Used From Domain Record) header.from=gmail.com policy.dmarc=none',
+  spf: { result: 'none' },
+  dkim: { result: 'pass' },
+  arc: { result: 'pass' },
+  dmarc: { policy: 'none', result: 'fail', reason: 'Used From Domain Record' }
+}
+```
 
 
 ## Contributors

index.js

@@ -37,6 +37,8 @@ if (!semver.satisfies(version, '>= 3.5'))
     `Python v3.5+ is required, you currently have v${version} installed`
   );
 
+const KEYS = ['spf', 'dkim', 'arc', 'dmarc'];
+
 function authenticateMessage(message, ...args) {
   const command = `python3 ${scripts.authenticateMessage} ${args.join(' ')}`;
   debug(command);
@@ -57,7 +59,53 @@ function authenticateMessage(message, ...args) {
     child.stdin.end();
     child.on('close', () => {
       if (stderr.length > 0) return reject(new Error(stderr.join('')));
-      resolve(stdout.join(''));
+      // Authentication-Results: mx1.forwardemail.net; spf=fail reason="SPF fail - not authorized" smtp.helo=jacks-macbook-pro.local [email protected]; dkim=fail; arc=none; dmarc=fail (Used From Domain Record) header.from=forwardemail.net policy.dmarc=reject
+      const result = { header: stdout.join('').trim() };
+      for (const key of KEYS) {
+        result[key] = {};
+      }
+
+      result.dmarc.policy = 'none';
+
+      const terms = result.header
+        .split(/;/)
+        .map((t) => t.trim())
+        .filter((t) => t !== '');
+
+      for (const term of terms) {
+        const split = term.split('=');
+        if (term.startsWith('spf=')) {
+          result.spf.result = split[1].split(' ')[0];
+          const index = term.indexOf('reason=');
+          if (index !== -1)
+            result.spf.reason = term
+              .slice(index + 'reason='.length)
+              .split('"')[1];
+        } else if (term.startsWith('dkim=')) {
+          result.dkim.result = split[1].split(' ')[0];
+          const index = term.indexOf('(');
+          if (index !== -1)
+            result.dkim.reason = term.slice(index + '('.length).split(')')[0];
+        } else if (term.startsWith('arc=')) {
+          result.arc.result = split[1].split(' ')[0];
+          // TODO: right now this does not return a comment due to this issue:
+          // <https://github.com/ValiMail/authentication-headers/issues/12
+        } else if (term.startsWith('dmarc=')) {
+          result.dmarc.result = split[1].split(' ')[0];
+          // reason
+          const index = term.indexOf('(');
+          if (index !== -1)
+            result.dmarc.reason = term.slice(index + '('.length).split(')')[0];
+          // policy
+          const policyIndex = term.indexOf('policy.dmarc=');
+          if (policyIndex !== -1)
+            result.dmarc.policy = term
+              .slice(policyIndex + 'policy.dmarc='.length)
+              .split(' ')[0];
+        }
+      }
+
+      resolve(result);
     });
   });
 }

test/test.js

@@ -29,10 +29,24 @@ test('authenticate message', async (t) => {
     'domain.of.sender.net'
   );
 
-  t.is(
-    result,
-    'Authentication-Results: example.com; spf=none smtp.helo=domain.of.sender.net smtp.mailfrom=test.com; dkim=pass header.d=forwardemail.net; arc=pass; dmarc=fail (Used From Domain Record) header.from=gmail.com policy.dmarc=none'
-  );
+  t.deepEqual(result, {
+    arc: {
+      result: 'pass'
+    },
+    dkim: {
+      result: 'pass'
+    },
+    dmarc: {
+      policy: 'none',
+      reason: 'Used From Domain Record',
+      result: 'fail'
+    },
+    header:
+      'Authentication-Results: example.com; spf=none smtp.helo=domain.of.sender.net smtp.mailfrom=test.com; dkim=pass header.d=forwardemail.net; arc=pass; dmarc=fail (Used From Domain Record) header.from=gmail.com policy.dmarc=none',
+    spf: {
+      result: 'none'
+    }
+  });
 });
 
 test('arc sign throws error with missing From header', async (t) => {
@@ -46,5 +60,4 @@ test('arc sign throws error with missing From header', async (t) => {
     ),
     { message: /IndexError: list index out of range/g }
   );
-  t.pass();
 });