reset msg on separated response(observe) with block2 option

[Thousif-khan]

am facing an issue,

1. node-coap is a client and sends a CON request with observe and block2 option.
2. serve response with ACK including block2 option with moreFlag set to false.
3. when the new data is ready at server its send a notification CON message with block2 and moreFlag=true here client sents RESET
   instead of ACK.
   Am i doing something wrong here.
   

[JKRhb]

Hi @Thousif-khan, thanks for reporting this issue. There is currently a bug regarding observe (#330) that might be related to this problem. A new version with these changes should be released soon (CC @Apollon77), maybe that fixes the issue.

Maybe you could try out the version from my fork already to see if the error disappears? Otherwise some more investigation is probably needed. Another thing you could try out is downgrading node-coap to 0.25.0 (which is the version before the switch to typescript began), this way we could rule out if it is a new bug or an edge case nobody noticed before.

[Thousif-khan]

Hi @JKRhb, i did some testings has you suggested,

1. Tested with 0.25.0 i was getting ACK and RST later.
2. I believe have found a bug, please have look at file agent.ts line 333. the request related token is deleted, if block and token is present but not check if observe is in request option.

please suggest.

[JKRhb]

2. I believe have found a bug, please have look at file agent.ts line 333. the request related token is deleted, if block and token is present but not check if observe is in request option.

Oh, thank you for testing this out! I guess #330 might also fix this problem, hopefully it will be merged and released soon.

[Thousif-khan]

No , #330 wont fix this issue. we need to add check for observe option present in the req. one way of doing it is
else if (block2 != null && packet.token != null && ((0, helpers_1.getOption)(packet.options, 'Observe')) == null ) { // check if no observe option present, then delete it.

[Apollon77]

Please re-check with v1.0.5 (even if your propoed change is not in there)

[Thousif-khan]

Hi @Apollon77, apologies for the delay, have tested with v1.0.5 and the issue still exists. getting same RST message. please take a look of what i have suggested.

[Thousif-khan]

can you try it out with the same setup has mine.

1. Coap Client sends request with observe and block2 option.
2. Coap Server responses with ACK on observe request (No piggy-bagged data here, since separated response model).
3. Coap Server sends CON message with block_0 and more-flag set. (at this point client should respond with empty ACK message and followed block_1 request, but am seeing RST message).

Reason for RST message should be, no token details found or token is deleted from client.

[Thousif-khan]

One more solution would be
https://github.com/mcollina/node-coap/blob/67c12da77a8548cea12f8cea02c5c4809b10e24a/lib/agent.ts#L335
added req.url.observe check
} else if (block2 != null && packet.token != null && req.url.observe == null) {

[Apollon77]

@JKRhb is the pther open PR adressing that maybe?

[JKRhb]

@JKRhb is the pther open PR adressing that maybe?

Oh, yeah, that could actually be the case! I would suggest merging #337 first and then revisiting the issue, trying out @Thousif-khan's approach. Thank you @Thousif-khan for the status updates and the suggestions!

[Apollon77]

Ok, merged ... so @Thousif-khan net try with githubb version?

[Thousif-khan]

sorry @Apollon77, didn't get you. what should be tried ?

[Apollon77]

Please install the lib GitHub and check the behavior again. If your issue is not fixed we need to check your proposals from above

[JKRhb]

Please install the lib GitHub and check the behavior again. If your issue is not fixed we need to check your proposals from above

I'm afraid we have a typescript related problem here again :/ #337 should have definitely fixed eclipse-thingweb/node-wot#728, though. Therefore, I think it is reasonable to already publish a new release and revisit this issue afterwards.

[Apollon77]

@Thousif-khan I will release a 1.0.8 soon which adress other observe issues ... please check if this is aloready enough to also fix your issue ... else we have #344 to try next :-)

[Thousif-khan]

Hi @Apollon77, issue persists. please make a setup has i suggested and test for yourself before next release. .

[JKRhb]

else if (block2 != null && packet.token != null && req.url.observe == null) {

Thanks for the feedback, then we should merge #343 now.