xamarin.forms - Xamarin Form - TaskCanceledException thrown on await client.PostAsync() -


very strange problem (all code in pcl).

when call await client.postasync() against webservice (api's), taskcanceledexception.

few things note:

this running fine on android devices. happens when run app on ios, but...

... make stranger, can make run on ios if use different (physical) server hosts api's query await client.postasync().

so,

to make more strange, both servers run same webservice, there 0 difference, difference servers on different sites different client. fault not queried webservice throwing timing out or cancelling request.

both servers have valid (trusted) ssl certificate it's not ssl related issue.

i stuck. have tried modernhttpclient , increaing client.timespan.

i checked ex.cancellationtoken.iscancellationrequested, false, it's pretty safe assume time of "timeout". however, when run post request postman manually against api, it's clear webservice works fine (there no timeout).

public class tokenservice {     private httpclient client;     private app app;      public tokenservice()     {         //client = new httpclient();          client = new httpclient(new nativemessagehandler());         client.timeout = timespan.fromminutes(30);          client.maxresponsecontentbuffersize = 256000;         app = (app)application.current;     }      public class tokenresponse     {         public string access_token;         public int32 expires_in;     }      public async task<string> getnewtoken()     {         // check if valid token stored , within expiry datetime          if(token.bearertoken != null)         {             if (token.expiry > datetime.now)                 return token.bearertoken;         }          var tokenulr = app.webserviceshostname + "/token";          var tokenresponse = new tokenresponse();          try         {             var content = new formurlencodedcontent(new[]             {                 // needs stored somewhere safe:                 new keyvaluepair<string, string>("username", "validusernamehere"),                 new keyvaluepair<string, string>("password", "validpasshere")             });              var response = await client.postasync(tokenulr, content); // <<***exception here              if (response.statuscode == httpstatuscode.ok)             {                 var token = await response.content.readasstringasync();                  tokenresponse = jsonconvert.deserializeobject<tokenresponse>(token);                  token.bearertoken = tokenresponse.access_token;                 token.expiry = datetime.now.addseconds(tokenresponse.expires_in - 30);                  return tokenresponse.access_token;             }             else             {                 return null;              }         }         catch(taskcanceledexception ex)         {             string message = ex.message;             string source = ex.source;             cancellationtoken token = ex.cancellationtoken;                return null;         }         catch(exception ex)         {             string test = ex.message;             return null;         }     } }

exception details:

{system.threading.tasks.taskcanceledexception: task canceled.
@ system.runtime.compilerservices.taskawaiter.throwfornonsuccess (system.threading.tasks.task task) [0x0002d] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:179 @ system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification (system.threading.tasks.task task) [0x0002e] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:156 @ system.runtime.compilerservices.taskawaiter.validateend (system.threading.tasks.task task) [0x0000b] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:128 @ system.runtime.compilerservices.taskawaiter`1[tresult].getresult () [0x00000] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:357 @ system.net.http.httpclienthandler+c__async0.movenext () [0x004c1] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/system.net.http/system.net.http/httpclienthandler.cs:391

--- end of stack trace previous location exception thrown --- @ system.runtime.exceptionservices.exceptiondispatchinfo.throw () [0x0000c] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 @ system.runtime.compilerservices.taskawaiter.throwfornonsuccess (system.threading.tasks.task task) [0x00027] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:176 @ system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification (system.threading.tasks.task task) [0x0002e] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:156 @ system.runtime.compilerservices.taskawaiter.validateend (system.threading.tasks.task task) [0x0000b] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:128 @ system.runtime.compilerservices.configuredtaskawaitable`1+configuredtaskawaiter[tresult].getresult () [0x00000] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:535 @ system.net.http.httpclient+c__async0.movenext () [0x000a9] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/system.net.http/system.net.http/httpclient.cs:276

--- end of stack trace previous location exception thrown --- @ system.runtime.exceptionservices.exceptiondispatchinfo.throw () [0x0000c] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 @ system.runtime.compilerservices.taskawaiter.throwfornonsuccess (system.threading.tasks.task task) [0x00027] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:176 @ system.runtime.compilerservices.taskawaiter.handlenonsuccessanddebuggernotification (system.threading.tasks.task task) [0x0002e] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:156 @ system.runtime.compilerservices.taskawaiter.validateend (system.threading.tasks.task task) [0x0000b] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:128 @ system.runtime.compilerservices.taskawaiter`1[tresult].getresult () [0x00000] in /library/frameworks/xamarin.ios.framework/versions/10.4.0.128/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/taskawaiter.cs:357 @ xamarinmo.services.tokenservice+d__4.movenext () [0x000e3] in c:\users\johns\onedrive\sources\winman api , xamain app\xamarinmo\xamarinmo\xamarinmo\services\tokenservice.cs:67 }

after many many hours, found solution:

it can fixed changing tls setting under project properties mono instead of apple. due bug in new apple tls default setting ssl/tls on ios.


Comments

Post a Comment

Popular posts from this blog

Is there a better way to structure post methods in Class Based Views -

i'm using class based views in django , never specify url in ajax calls , omit action parameter in form because know these requests go through post method of class based view. notice view - profile page make many requests depending on user updating on page - post method become convoluted , if/else mess example: def post(self, request, *args, **kwargs): # handle user changing available date if request.post.get('availabledate') != none: self.updateavailabledate(request) return jsonresponse({'result':'success'}) if request.post.get('newprojectname') != none: creative_user = creativeuserprofile.objects.get(id = request.user.id) project = project.create_project(creative_user, request.post['newprojectname']) project.save() return jsonresponse({'projectid': project.id }) if request.post.get('projectimage') != none , request.files['file']: proj
Read more

performance - Why is XCHG reg, reg a 3 micro-op instruction on modern Intel architectures? -

i'm doing micro-optimization on performance critical part of code , came across sequence of instructions (in at&t syntax): add %rax, %rbx mov %rdx, %rax mov %rbx, %rdx i thought had use case xchg allow me shave instruction , write: add %rbx, %rax xchg %rax, %rdx however, dimay found agner fog's instruction tables , xchg 3 micro-op instruction 2 cycle latency on sandy bridge, ivy bridge, broadwell, haswell , skylake. 3 whole micro-ops , 2 cycles of latency! 3 micro-ops throws off 4-1-1-1 cadence , 2 cycle latency makes worse original in best case since last 2 instructions in original might execute in parallel. now... cpu might breaking instruction micro-ops equivalent to: mov %rax, %tmp mov %rdx, %rax mov %tmp, %rdx where tmp anonymous internal register , suppose last 2 micro-ops run in parallel latency 2 cycles. given register renaming occurs on these micro-architectures, though, doesn't make sense me done way. why wouldn't register renamer
Read more

jquery - Responsive Navbar with Sub Navbar -

good day, forgive me nav vocabulary not best. if question confusing apologize. i'm working on navigation bar needs centered on page @ 768px , above. items in nav open (or perhaps toggle) subnav lives directly below. these nav should appear centered on page. i have been able work through responsive portion of nav bar, having main items align vertically , sub nav menu of each item roll out below, , gave them indent separation. working well. however, issue not responsive side, behavior @ width greater 768px. happens toggling menu's sub navigation pushes other main items down page below sub nav. here's code: $(document).ready(function () { //stick in fixed 100% height behind navbar don't wrap $('#slide-nav.navbar-inverse').after($('<div class="inverse" id="navbar-height-col"></div>')); $('#slide-nav.navbar-default').after($('<div id="navbar-height-col"></d
Read more