DioError [DioErrorType.other]: HttpException: Connection closed before full header was received

[wmhseir3]

hi, I have recently obtained one onvif nvt which is working smoothly using the top download onvif app from Google play.
However, this new nvt can not even run the "await onvif.initialize();" The DioError messages captured are as followings. I am suspecting the Dio plugin may have compatibility issues as with easyonvif. As issue #3/4 and this issue are all related with it. Can you please change the Dio to else one which might help solving these issues?

E/flutter (13446): [ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: Exception: DioError [DioErrorType.other]: HttpException: Connection closed before full header was received, uri = http://192.168.1.106:8000/onvif/device_service
E/flutter (13446): #0 DioMixin.assureDioError (package:dio/src/dio_mixin.dart:819:20)
E/flutter (13446): #1 DioMixin._dispatchRequest (package:dio/src/dio_mixin.dart:678:13)
E/flutter (13446):
E/flutter (13446): #2 DioMixin.fetch.. (package:dio/src/dio_mixin.dart)
E/flutter (13446):
E/flutter (13446):
E/flutter (13446): #0 Soap.send (package:easy_onvif/src/soap.dart:34:7)
E/flutter (13446):
E/flutter (13446): #1 Soap.retrieveEnvlope (package:easy_onvif/src/soap.dart:43:26)
E/flutter (13446):
E/flutter (13446): #2 DeviceManagement.getSystemDateAndTime (package:easy_onvif/src/deviceManagement.dart:145:22)
E/flutter (13446):
E/flutter (13446): #3 Onvif.initialize (package:easy_onvif/src/onvif.dart:33:22)
E/flutter (13446):
E/flutter (13446): #4 _MyHomePageState._initialize (package:testeasyonvif/main.dart:79:5)

[faithoflifedev]

@wmhseir3, the latest PR #7 is an attempt to address this issue. I found the following info that speaks broadly to the issue:

• HttpException: Connection closed while receiving data cfug/dio#1185
• https://stackoverflow.com/questions/55879550/how-to-fix-httpexception-connection-closed-before-full-header-was-received

Though I don't think either necessarily applies here. I did see that I was creating a new Dio instance for every SOAP request. With the latest changes, that is no longer the case. Let me know if this resolves things for you.

[faithoflifedev]

Btw, easy_onvif 0.0.11 has now been published.

[wmhseir3]

hi, the 0.0.11 won't get through with this issue the same DioError appears as followings:
E/flutter (16871): [ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: Exception: DioError [DioErrorType.other]: HttpException: Connection closed before full header was received, uri = http://192.168.1.102:8000/onvif/device_service
E/flutter (16871): #0 DioMixin.assureDioError (package:dio/src/dio_mixin.dart:819:20)
E/flutter (16871): #1 DioMixin._dispatchRequest (package:dio/src/dio_mixin.dart:678:13)
E/flutter (16871):
E/flutter (16871): #2 DioMixin.fetch.. (package:dio/src/dio_mixin.dart)
E/flutter (16871):
E/flutter (16871):
E/flutter (16871): #0 Soap.send (package:easy_onvif/src/soap.dart:34:7)
E/flutter (16871):
E/flutter (16871): #1 Soap.retrieveEnvlope (package:easy_onvif/src/soap.dart:43:26)
E/flutter (16871):
E/flutter (16871): #2 DeviceManagement.getSystemDateAndTime (package:easy_onvif/src/deviceManagement.dart:145:22)
E/flutter (16871):
E/flutter (16871): #3 Onvif.initialize (package:easy_onvif/src/onvif.dart:33:22)

I tried to add the timeout lines as followings but still the same. Any other workaround?
response = await dio.post(url,
data: requestData,
options: Options(
sendTimeout: 2000,
receiveTimeout: 0,
headers: {
Headers.contentTypeHeader: 'text/xml; charset=utf-8',
Headers.contentLengthHeader: requestData.length
}));

[faithoflifedev]

@wmhseir3, I think in this case I'd need a minimal code sample to try to replicate the issue. From what I've read about the problem it may be related to the size of the SOAP response. Without being able to replicate this any further changes I make are purely guess work. Any chance you can provide a small sample of your code?

[wmhseir3]

hi, just got your reply. My sample code is simple. I just used the flutter new project as in the Android Studio. And add changes with the following codes. This issue is just occured with the "await onvif.initialize();" line. Can you please send me an email ([email protected]) privately. I can then advise how you can reproduce the issue remotely in your end easily. Thanks.

@OverRide
void initState() {
super.initState();
_initialize();
}

_initialize() async {
// final config = loadYaml(File('assets/config.yaml').readAsStringSync());
var onvif = Onvif(
// host: '192.168.1.102:8000',
host: '192.168.1.103:2020',
username: 'admin',
password: 'aa888888');
//initiate connection
await onvif.initialize();
}

[faithoflifedev]

@wmhseir3 , thanks for this. I created a flutter app that connects to me to my main test device and everything worked fine. I then changed to connect to an alternate device and I'm starting to see some errors. So far, not the same as you provided, but I see this a progress :-)

[wmhseir3]

hi, like to see your progress next. Let me know, if you are available to see my test device.

[faithoflifedev]

Please see my recent comment at #3

[wmhseir3]

I tried 0.12.0 with the flutter_model example. It's still getting the HttpException: Connection closed before full header was received" with the new 2nd nvt. I would like to offer you the steps for you to test with this nvt remotely in your end. Can you please send email to me @[email protected]?