fix getting postUri in SentryClient

1. dsn may specify non-regular port
2. dsn may contains some paths before the projectID

lib/sentry.dart

@@ -160,8 +160,23 @@ class SentryClient {
   User userContext;
 
   @visibleForTesting
-  String get postUri =>
-      '${dsnUri.scheme}://${dsnUri.host}/api/$projectId/store/';
+  String get postUri {
+    var port = dsnUri.hasPort &&
+            ((dsnUri.scheme == 'http' && dsnUri.port != 80) ||
+                (dsnUri.scheme == 'https' && dsnUri.port != 443))
+        ? ':${dsnUri.port}'
+        : '';
+    var pathLength = dsnUri.pathSegments.length;
+    var apiPath;
+    if (pathLength > 1) {
+      // some paths would present before the projectID in the dsnUri 
+      apiPath =
+          (dsnUri.pathSegments.sublist(0, pathLength - 1) + ['api']).join('/');
+    } else {
+      apiPath = 'api';
+    }
+    return '${dsnUri.scheme}://${dsnUri.host}${port}/$apiPath/$projectId/store/';
+  }
 
   /// Reports an [event] to Sentry.io.
   Future<SentryResponse> capture(

test/sentry_test.dart

@@ -11,7 +11,8 @@ import 'package:test/test.dart';
 
 const String _testDsn = 'https://public:[email protected]/1';
 const String _testDsnWithoutSecret = 'https://[email protected]/1';
-
+const String _testDsnWithPath = 'https://public:[email protected]/path/1';
+const String _testDsnWithPort = 'https://public:[email protected]:8888/1';
 void main() {
   group('$SentryClient', () {
     test('can parse DSN', () async {
@@ -34,6 +35,24 @@ void main() {
       await client.close();
     });
 
+    test('can parse DSN with path', () async {
+      final SentryClient client = new SentryClient(dsn: _testDsnWithPath);
+      expect(client.dsnUri, Uri.parse(_testDsnWithPath));
+      expect(client.postUri, 'https://sentry.example.com/path/api/1/store/');
+      expect(client.publicKey, 'public');
+      expect(client.secretKey, 'secret');
+      expect(client.projectId, '1');
+      await client.close();
+    });
+    test('can parse DSN with port', () async {
+      final SentryClient client = new SentryClient(dsn: _testDsnWithPort);
+      expect(client.dsnUri, Uri.parse(_testDsnWithPort));
+      expect(client.postUri, 'https://sentry.example.com:8888/api/1/store/');
+      expect(client.publicKey, 'public');
+      expect(client.secretKey, 'secret');
+      expect(client.projectId, '1');
+      await client.close();
+    });
     test('sends client auth header without secret', () async {
       final MockClient httpMock = new MockClient();
       final ClockProvider fakeClockProvider =