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Client with http-server [message #1866807]

Thu, 06 June 2024 21:16

Eclipse User

Hello

I want to get and push parameters to a http-server . I build forte from source and activated http=on.
Sadly it's not actually working. My main problem is to set up the id right.
At the moment I only get NO_SOCKET or INVALID_ID as status
Can someone give me one example for get and one for push.
I'm also not sure if I have a bug.
Or are there another common mistakes.

In my test I just tried to read strings from the server.
Thank you all
Dustin

[Updated on: Thu, 06 June 2024 21:24] by Moderator

Re: Client with http-server [message #1866810 is a reply to message #1866807]

Thu, 06 June 2024 21:18

Eclipse User

Sry for that many topics I always get an error my bad.

Re: Client with http-server [message #1866813 is a reply to message #1866810]

Thu, 06 June 2024 22:14

Eclipse User

It's taken care of, Dustin.

Re: Client with http-server [message #1866816 is a reply to message #1866813]

Fri, 07 June 2024 02:20

Eclipse User

Did you take a look at https://eclipse.dev/4diac/en_help.php?helppage=html/communication/http.html for some examples? Can you share how are you setting the PARAMS and which Function Block are you using to get the string of the server?

Re: Client with http-server [message #1866822 is a reply to message #1866807]

Fri, 07 June 2024 08:49

Eclipse User

Could solve my problem with the GET-request
thank you.
I built my 4diac IDE again and created a new FB and now it works.
Helped me also: https://www.eclipse.org/forums/index.php/t/1109481/

[Updated on: Fri, 07 June 2024 10:40] by Moderator

Re: Client with http-server [message #1866825 is a reply to message #1866816]

Fri, 07 June 2024 10:36

Eclipse User

I could successfully build a get connection to a http-server.

But PUT or POST isn't working at the moment. My Server runs local (127.0.0.1) on PORT:9000 and I used on of the examples so that my ID is:

"http[127.0.0.1:9000/put;PUT;application/json]

I used from the Type Libary the Client_1 FB.

Thanks for the help
Dustin

Attachment: HTTP-Client.png
(Size: 230.25KB, Downloaded 81 times)

Re: Client with http-server [message #1866828 is a reply to message #1866816]

Fri, 07 June 2024 10:38

Eclipse User

tried different IP-address so in my screenshot was the wrong one
I corrected the address back to 127.0.0.1 and the problem is still existing

Attachment: HTTP-Client.png
(Size: 230.17KB, Downloaded 74 times)

[Updated on: Fri, 07 June 2024 10:47] by Moderator

Re: Client with http-server [message #1866831 is a reply to message #1866828]

Sat, 08 June 2024 07:47

Eclipse User

Do you get any error on forte? Probably the problem is because you have a RD in the client using POST/PUT. The documentation is wrong in that sense:

For a PUT/POST request you can set the data to be sent in two ways:
- On the PARAMETERS in the PARAM data input (see below)
- In a RD (exactly 1) of the client FB -----> This should be SD, and also should be clarified that no RD.

Re: Client with http-server [message #1866843 is a reply to message #1866831]

Sat, 08 June 2024 22:50

Eclipse User

I tried a configuration with and without RDs.
My Forte shows like in the .png that every client needs two RDs.

When I stop the program I get the error that the string to insert was empty.

I don't understand my mistake.

Thanks for your help and tips

Attachment: PUT_Client_1_0.png
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Attachment: PUT_Client_1_2.png
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Re: Client with http-server [message #1866852 is a reply to message #1866843]

Sun, 09 June 2024 05:12

Eclipse User

From the 4diac FORTE output I assume that you are using the develop branch for 4diac FORTE. AFAIR Monika did some improvements on the HTTP layer for that. She also updated and fixed the documentation. The new documentation can be found here: https://github.com/eclipse-4diac/4diac-documentation/blob/main/src/communication/http.adoc

This new documentation is also already part of the 4diac IDE documentation. However not yet on the web page. The reason for that is that we are currently reworking the web-page and changing the documentation on the old on is not really worth it.

PS: We are always happy for any support on improving our documentation.

Re: Client with http-server [message #1866933 is a reply to message #1866852]

Tue, 11 June 2024 01:25

Eclipse User

I used now the develop version of forte. I also created a client_3_2 (3SD and 2RD). I was able to create a GET-communication with my server.
But the POST and PUT-requests doesn't work at the moment.
I created a Server who accepts all types of requests GET/POST/PUT. It worked if I did a curl request.

POST-request: curl -X POST http://localhost:8000/daten -H "Content-Type: application/json" -d "{\"name\": \"John\", \"alter\": 30, \"verheiratet\": true, \"haustiere\": [\"Hund\", \"Katze\"]}"

PUT-request: curl -X PUT http://localhost:8000/daten -H "Content-Type: application/json" -d "{\"name\": \"John\", \"alter\": 30, \"verheiratet\": false, \"haustiere\": [\"Hamster\"]}"

My main issue is that the json-data not correctly arrives. Some data is arriving certified trough the line: Empfangene Daten erhalten -b' '
But not the right one.

I can't copy my curl -body (json-string) directly because I would need double qoutes around my wstring-body, but every double quotes around e.g. "name" causes an issue.
With single quotes and backslashes I'm getting the same result.

I added in the files my used python http-server, my post & put request and my client configuration.

Thanks for your help
Dustin

Attachment: Client-FB 2024-06-11 064011.png
(Size: 146.60KB, Downloaded 79 times)
Attachment: Johnserver.py
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Attachment: PUT 2024-06-11 072330.png
(Size: 409.61KB, Downloaded 80 times)
Attachment: POST 2024-06-11 062201.png
(Size: 389.55KB, Downloaded 78 times)

Re: Client with http-server [message #1866945 is a reply to message #1866933]

Tue, 11 June 2024 05:37

Eclipse User

Not sure if this helps but the escape character for IEC 61131-3 Strings and WStrings is the $ instead of the \. So if you need to escape double quotes you need to use $" in 4diac IDE.

Re: Client with http-server [message #1866963 is a reply to message #1866945]

Tue, 11 June 2024 05:53

Eclipse User

not sure if it helps, but the inputs of this fb are of type ANY and i think you should add a type e.g. STRING#'' for all empty inputs, and STRING#'my text' for your input with content as well as WSTRING#"my ID"

Re: Client with http-server [message #1866999 is a reply to message #1866963]

Tue, 11 June 2024 17:29

Eclipse User

Thanks for all of you help!
Monikas last tip solved my problem from the former message.
I add two screenshots and my http-server here so I can get involved in the documentation or if someone else have the same problems.

Attachment: PUT_Client_succesfull.png
(Size: 185.42KB, Downloaded 93 times)
Attachment: PUT_Client_succesfull_watched.png
(Size: 521.46KB, Downloaded 76 times)
Attachment: puthttp3.py
(Size: 0.69KB, Downloaded 77 times)

Re: Client with http-server [message #1867023 is a reply to message #1866999]

Wed, 12 June 2024 09:47

Eclipse User

Thx for the feedback. If you have ideas how the documentation can be improved feel free to change it and submit a pull request. The great advantage of our new AsciDoc format and github is that you can directly edit the file on github and contribute your suggestion as PR.

Re: Client with http-server [message #1867029 is a reply to message #1867023]

Wed, 12 June 2024 09:58

Eclipse User

I will do. I have a hard schedule in the next two weeks. But after this I will add my learnings to the Dokumentation.

Re: Client with http-server [message #1867035 is a reply to message #1867029]

Wed, 12 June 2024 10:06

Eclipse User

This would be great. In the mean time all the best for your hard schedule.

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