fix: #372 [Bug] Android: malformed empty multipart requests

src/android/com/silkimen/cordovahttp/CordovaHttpBase.java

@@ -189,8 +189,9 @@ abstract class CordovaHttpBase implements Runnable {
       }
 
       // prevent sending malformed empty multipart requests (#372)
-      if (buffers.length == 0) {
-        request.contentType(HttpRequest.CONTENT_TYPE_FORM);
+      if (buffers.length() == 0) {
+        request.contentType("multipart/form-data; boundary=00content0boundary00");
+        request.send("\r\n--00content0boundary00--\r\n");
       }
     }
   }

test/e2e-specs.js

@@ -1121,11 +1121,18 @@ const tests = [
       var options = { method: 'post', data: formData };
       cordova.plugin.http.sendRequest(url, options, resolve, reject);
     },
-    validationFunc: function (driver, result) {
+    validationFunc: function (driver, result, targetInfo) {
       helpers.checkResult(result, 'resolved');
 
       var parsed = JSON.parse(result.data.data);
-      parsed.headers['Content-Type'].should.be.equal('application/x-www-form-urlencoded');
+
+      if (targetInfo.isAndroid) {
+        // boundary should be sent correctly on Android
+        parsed.headers['Content-Type'].should.be.equal('multipart/form-data; boundary=00content0boundary00');
+      } else {
+        // falling back to empty url encoded request on iOS
+        parsed.headers['Content-Type'].should.be.equal('application/x-www-form-urlencoded');
+      }
     }
   },
 ];