Hi there,
Please can someone tell me how I would go about checking in my mobile application if my appserver is down?
Basically on Login where I validate the user credentials I run my login business entity read method but this does not return any errors when the appserver is down. How do I check if my appserver is up and if my appserver up I want to do my appserver call, otherwise display a message to the user.
Thanks in advance.
OpenEdge Management is capable of notifying you about AppServer status via email alerts so you know immediately about AppServer not running. It also provides charts and reports for historical data.
In addition to Matt's point, if you are using an OpenEdge 11.4 or later Web application as the back end, your mobile application code can use the progress.data.Session object's ping() method to determine the status of the back end, including whether the AppServer is running. If ping() returns false, it will also provide a string constant that identifies the reason for the failure. If the AppServer is down, that reason will be progress.data.Session.APPSERVER_OFFLINE ("AppServer is not available"). You could call ping() just before calling your read method.
An alternative is to have the Session object call ping automatically for you on a set interval, and subscribe to the Session object's offline event. You would use the Session.pingInterval property to start the automatic pinging, and also call Session.subscribe() to subscribe to the offline event (and you would want to subscribe to the online event, too). If you are using an 11.4 back end, one of the reasons the offline event will be fired is that the AppServer is down, and you handler will receive progress.data.Session.APPSERVER_OFFLINE as the offlineReason argument (2nd parameter).
The 11.4 documentation covers ping(), pingInterval, and the offline event, but let me know if you have any questions about how to use them in your case.
Unfortunately, OE prior to 11.4 didn't have support for telling a Mobile client app that the AppServer is down. I'm puzzled, though, that you are not receiving an error on your read call. I would expect you to receive an error of some sort if the data can't be retrieved.
Regards,
--Wayne
Hello,
>> Basically on Login where I validate the user credentials I run my login business entity read method but this does not return any errors when the appserver is down.
The usage of the offline and online events in the Session object and usage of ping() would probably be the solution for this issue.
Just in case, I wanted to mentioned that you should get an error message when the the AppServer is down. Perhaps, the response is empty, but you should still get an error.
My testing shows that the READ request fails with Status Code 500 Internal server Error.
Thanks.
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Meyrick Flanegan |
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Developer - Managed Services |
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Email: mflanegan@elcb.co.za |
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ELCB Information Services (Pty) Ltd |
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Customer Service Email elcb@elcb.co.za · www.elcb.co.za |
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E A S T L O N D O N Tel: +27(43) 704 0700 Fax: +27(43) 704 0701 |
J O H A N N E S B U R G Tel: +27(10) 035 0310 Fax: +27(10) 035 0311 |
P O R T E L I Z A B E T H Tel: +27(41) 373 0529 Fax: +27(86) 650 0135 |
Hello,
>> Basically on Login where I validate the user credentials I run my login business entity read method but this does not return any errors when the appserver is down.
The usage of the offline and online events in the Session object and usage of ping() would probably be the solution for this issue.
Just in case, I wanted to mentioned that you should get an error message when the the AppServer is down. Perhaps, the response is empty, but you should still get an error.
My testing shows that the READ request fails with Status Code 500 Internal server Error.
Thanks.
Flag this post as spam/abuse.
Hi Meyrick,
What version of OpenEdge did you use to create the Web application / service that is running on the back end?
--Wayne
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Meyrick Flanegan |
|
Developer - Managed Services |
|
Email: mflanegan@elcb.co.za |
|
|
|
ELCB Information Services (Pty) Ltd |
|
Customer Service Email elcb@elcb.co.za · www.elcb.co.za |
|
E A S T L O N D O N Tel: +27(43) 704 0700 Fax: +27(43) 704 0701 |
J O H A N N E S B U R G Tel: +27(10) 035 0310 Fax: +27(10) 035 0311 |
P O R T E L I Z A B E T H Tel: +27(41) 373 0529 Fax: +27(86) 650 0135 |
Hi Meyrick,
What version of OpenEdge did you use to create the Web application / service that is running on the back end?
--Wayne
Flag this post as spam/abuse.
If the back end is 11.3.2, it doesn't have the special feature that the client Session uses to tell whether the AppServer is running. Unfortunately, that means that the ping and offline events can only tell you about the status of the server and the Web application (and the connection). The 500 that you get when you do a read is the only information you'll get, but of course you could get 500 for various reasons, not just the AppServer being down.
|
Meyrick Flanegan |
|
Developer - Managed Services |
|
Email: mflanegan@elcb.co.za |
|
|
|
ELCB Information Services (Pty) Ltd |
|
Customer Service Email elcb@elcb.co.za · www.elcb.co.za |
|
E A S T L O N D O N Tel: +27(43) 704 0700 Fax: +27(43) 704 0701 |
J O H A N N E S B U R G Tel: +27(10) 035 0310 Fax: +27(10) 035 0311 |
P O R T E L I Z A B E T H Tel: +27(41) 373 0529 Fax: +27(86) 650 0135 |
If the back end is 11.3.2, it doesn't have the special feature that the client Session uses to tell whether the AppServer is running. Unfortunately, that means that the ping and offline events can only tell you about the status of the server and the Web application (and the connection). The 500 that you get when you do a read is the only information you'll get, but of course you could get 500 for various reasons, not just the AppServer being down.
Flag this post as spam/abuse.
Hello Meyrick,
> Currently when this happens, the user keeps clicking the login button but nothing is happening.
Depending on the sequence that you are using for the login button, you may need to test whether the call to login(), addcatalog(), or fill() failed. Since you are using JSDO Services, you should be able to specify code for the error event handler, or Login or Read.
I hope this helps.