I am using spring-cloud-starter-hystrix:1.2.3.RELEASE in a Spring Boot application. I have 1 HystrixCommand, that I can execute successfully.
After that I called
localhost:8080/hystrix.stream
however this Request loads forever and doesn't respond. On Google I cannot find anything about this.
This happens if no command has been executed yet and therefor there are no metrics to publish in the stream.
The 'workaround' is to execute a Hystrix command.
This happens in Hystrix 1.5.8 and earlier. The behavior was changed in Hystrix 1.5.9 that was released yesterday. It will now publish a ping message if there are no metrics to publish.
This change was made to fix a bug where the stream would not detect closed connections when there were no metrics to publish. See Hystrix bug 1430 for more information.
Make sure you have the #EnableHystrixDashboard annotation added to the dashboard application. Then go to http://{dashboard-application:port}/hystrix.stream. On this page you will be asked to enter the URL of Hystrix application which is annotated with #EnableCircuitBreaker and of which you want to monitor the stream.
Related
I am trying to create an Event using Microsoft Graph SDK, as following the document #
https://learn.microsoft.com/en-us/graph/api/user-post-events?view=graph-rest-beta&tabs=csharp
1.Created "authProvider"
2.Created GraphClient with above AuthProvider
3.Creating Event using
The event is not creating also no exception/error is throwing, Could any one help me here?
This is happening because this call is being made with same transactionId frequently. It avoids unnecessary retries on the server.
It is an optional parameter , just comment out this property and try again. It should work.
Note : This identifier specified by a client app for the server , to avoid redundant POST operations in case of client retries to create the same event and also useful when low network connectivity causes the client to time out before receiving a response from the server for the client's prior create-event request.
More info is required here, as the reply from Allen Wu stated. without any details I would focus my efforts on the authprovider piece and azure app registration piece. as the rest of the example is just sending a post request to graph api.
but what is recommended really depends on what type of application you are trying to build. eg. is it a service daemon, a web app, mobile app, desktop app, single page app, etc.
I've a simple route
from(
"myQuartz://EMAIL_Route?cron=0+0/5+*+*+*+?")
.routeId("EMAIL_Route")
.shutdownRunningTask(
ShutdownRunningTask.CompleteCurrentTaskOnly)
.beanRef("errorReportProcessor")
.filter((body().isNotNull()))
.to("smtp://smtpHost?From=someone&to=someoneElse&Subject=something").end();
Even if I shutdown the application in Websphere application server, I still continue to get emails. The scheduler/thread is not stopping. In my quartz properties file, I also tried
org.quartz.scheduler.makeSchedulerThreadDaemon=true
but, fruitless. The Camel, Quartz and Mail component version is 2.12.4. Spring 3.2.5.Release. Websphere 8.
SystemOut.log files clearly mentions, the application stopped without errors. However, I can see a java.exe instance running in task-manager.
OK. I found the issue was with missing "root-app-context". Once, I configured the "root-app-context", the Cron-scheduler is now stopping and no more stranded threads. :)
Even the extra configuration to makeSchedulerThreadDaemon was not required.
org.quartz.scheduler.makeSchedulerThreadDaemon=true
I have a Google App Engine servlet that is cron configured to run once a week. Since it will take more than 1 minute of execution time, it launches a task (i.e. another servlet task/clear) on the application's default push task queue.
Now what I'm observing is this: if the task causes an exception (e.g. NullPointerException inside its second servlet), this gets translated into HTTP status 500 (i.e. HttpURLConnection.HTTP_INTERNAL_ERROR) and Google App Engine apparently reacts by immediately relaunching the same task again. It announces this by printing:
Web hook at http://127.0.0.1:8888/task/clear returned status code 500. Rescheduling..
I can see how this can sometimes be a feature, but in my scenario it's inappropriate. Can I request that Google App Engine should not do such automatic rescheduling, or am I expected to use other status codes to indicate error conditions that would not cause rescheduling by its rules? Or is this something that happens only on the dev. server?
BTW, I am currently also running other tasks (with different frequencies) on the same task queue, so throttling reschedules on the level of task queue configuration would be inconvenient (so I hope there is another/better option too.)
As per https://developers.google.com/appengine/docs/java/taskqueue/overview-push#Java_Task_execution - the task must return a response code between 200 and 299.
You can either return the correct value, set the taskRetryLimit in RetryOptions or check the header X-AppEngine-TaskExecutionCount when task launches to check how many times it has been launched and act accordingly.
I think I've found a solution: in the Java API, there is a method RetryOptions#taskRetryLimit, which serves my case.
I am unable to update my frontends nor my backends. I get the error message 'Version is not ready'. This bug has persisted for coming up to 24 hours now. I have a task perpetually running in a queue. My best guess is that this task is stopping the update. I am unable to delete the task as it is perpetually running, nor can I delete the queue as I am unable to upload a new queue.yaml definition. The same task previously failed due to a maximum recursion error as I had a synchronous RPC within an asynchronous tasklet.
I'm pretty sure the fix will require someone from the GAE side forcibly resetting the task queue. Thus, this question would be more suitably directed to the GAE team with details about my app in a less public forum. Though, from what I can see, they do not allow direct support questions and suggest posting the question here. My follow up question, then, is when you have a GAE issue that requires action from the GAE team - how do you get hold of them (other than paying US$500/month for a premium support account)?
EDIT:
The task is/was meant to be running on a backend instance. I intended to shutdown all backend and frontend instances via the console assuming that they would cancel the task and restart themselves. But I found that only one frontend instance was running - no backends. After shutting down that frontend instance, the dashboard has reported that I have 0 instances running, yet the website is still serving and the task remains perpetually running.
EDIT:
Disabling the app stopped the task from running. After reenabling the app, I was able to update it. Though I am left with a ghost task in my queue.
If you have a stuck task queue job, I'd try disabling the queue and killing the instance running that job. If that doesn't work, I'd try disabling the app temporarily.
I'm trying to make http requests from my Google App Engine webapp, and discovered I have to use URLConnection since it's the only whitelisted class. The corresponding Clojure library is clojure.contrib.http.agent, and my code is as follows:
(defroutes example
(GET "/" [] (http/string (http/http-agent "http://www.example.com")))
(route/not-found "Page not found"))
This works fine in my development environment- the browser displays the text for example.com. But when I test it out with Google's development app server:
phrygian:example wei$ dev_appserver.sh war
2010-09-28 14:53:36.120 java[43845:903] [Java CocoaComponent compatibility mode]: Enabled
...
INFO: The server is running at http://localhost:8080/
It just hangs when I load the page. No error, or anything. Any idea what might be going on?
http-agent creates threads so that might be why it does not work.
From the API documentation:
Creates (and immediately returns) an Agent representing an HTTP
request running in a new thread.
You could try http-connection, which is a wrapper around HttpURLConnection, so this should work.
Another alternative is to try clj-http. The API seems to be a bit more high-level, but it uses Apache HttpComponents which might be blacklisted.
I am guessing http.async.client is a definite no-go due to its strong asynchronous approach.
You might want to try appengine.urlfetch/fetch from appengine-clj (http://github.com/r0man/appengine-clj, also in clojars)