Hana express edition and the oData service availability

[former_member203179]

Hi SAP experts,

we are running the HXE successfully and all is working nice - but there is a problem with the deployed running oData services.

We created a MTA application and deployed it, so we can see it in the application monitor after we run the oData service.
The oData service is also running without problems but only a certain time - and we don't know why and if this is a bug or a feature.

After an hour or some time passed the service give this response:
"An error occurred. Please open the SAP Web IDE Run console to view more information about the error."

When we restart the application in the HXE application monitor it is available again - for a certain time period, after which the same error occurred again.
Is that something we can configure or do we need to do something different when we want to have an oData service which is available all the time ?

We built the service with part1 and part2 explanation from this blog: https://blogs.sap.com/2017/05/17/sap-hana-express-xsa-application-part-1/
its an oData V2 with HDI and NodeJs module.

maybe somebody faced the same or can help here ?

All the best,
Thomas Schmidt

[former_member203179]

I just tested again and checked the log, here I can see the service is available but then in one point of time an exception occurred.

Do somebody know why and if this is because of the set up or a hxe bug or something ?

the log is okay when the service start:

[1499692936000] [RTR] OUT 10.230.11.14 - - to 10.0.20.117:51020 "GET /service.xsodata/?$format=json HTTP/1.1" 200 sent 163 in 16 by 00W-d079cfa5-6b61-4769-b597-bb55d76ee87c

[1499693578000] [RTR] OUT 10.230.11.13 - - to 10.0.20.117:51020 "GET /service.xsodata/?$format=json HTTP/1.1" 200 sent 163 in 15 by 00W-d079cfa5-6b61-4769-b597-bb55d76ee87c

but after a time this error is thrown :

[1499697179288] [APP/1-3] ERR events.js:160
[1499697179292] [APP/1-3] ERR throw er; // Unhandled 'error' event
[1499697179292] [APP/1-3] ERR ^
[1499697179292] [APP/1-3] ERR
[1499697179292] [APP/1-3] ERR Error: read ECONNRESET
[1499697179292] [APP/1-3] ERR at exports._errnoException (util.js:1022:11)
[1499697179292] [APP/1-3] ERR at TCP.onread (net.js:569:26)

this also occured in the test for other oData V2 services via the Node.js module - and from that point in time the service is not reachable anymore.

best,
Thomas

[former_member203179]

We found a good description for the mentioned error:

https://stackoverflow.com/questions/17245881/node-js-econnreset#answer-answer-17637900

So is this an error in the node.js module implementation in the HXE where a trown error is somewhere not handled and cause the exception we also face in the application error log when the odata service stops working ?

[1499697179288] [APP/1-3] ERR events.js:160
[1499697179292] [APP/1-3] ERR throw er; // Unhandled 'error' event
[1499697179292] [APP/1-3] ERR ^
[1499697179292] [APP/1-3] ERR
[1499697179292] [APP/1-3] ERR Error: read ECONNRESET
[1499697179292] [APP/1-3] ERR at exports._errnoException (util.js:1022:11)
[1499697179292] [APP/1-3] ERR at TCP.onread (net.js:569:26)

[former_member203179]

We now tested the odata V4 java module which keeps working without problems.

SO we assume its the node.js server or something together with the hxe config.
Does somebody else faces such issues - or can somebody confirm that there is a continues running odata V2 nodejs module hxe based service running without problems ?