[Solved] Webhook Pin Limits


I’m using a WebHook to post to ThingSpeak with a custom PIN provided to the webhook via virtual PIN eg…
Blynk.virtualWrite(V31, tsdata);

This /pin/ value works

This /pin/ doesn’t work

Debugging against requestb.in with another WebHook VPIN with /pin/ in the body, also shows the text correctly coming through for the first but blank for the second.

Is there a length limit for the /pin/ value for use in webhooks?

Thanks in advance - Russ

It used to be 2 or 3 and we requested an increase which I thought went to unlimited even though we only requested 4 or 5.

@Dmitriy is it unlimited despite the OP’s assessment?

Thanks @Costas. This is technically just 1 field as I read the 5 limit, and wanted 6 or more (max 8 per Thinkspeak Channel). If you think the field limit was removed, I will test down that path :slight_smile: .

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Update. So although the /pin[5]/ and above doesn’t turn green in the App, it does indeed show up correctly in the the body sectin of my tests through to requestb.in. Unfortunately my POST to https://api.thingspeak.com/update isn’t fairing so whell. Could be my body format though … the digging continues

@russelltomkins I think this is the GitHub commit for unlimited https://github.com/blynkkk/blynk-library/commit/cdec83ced5efbd3de00a8552787fd25dc0333333 following discussion in this thread Use webhook to PUT data to google sheets?

See comment around number 42 by @vshymanskyy which reminds you to ensure SENDBYTES is big enough when sending unlimited parameters with virtualWrite(). READBYTES will need to be big enough for Webhook reponse.

Please note that I have pushed a new feature - unlimited number of parameters for setProperty and virtualWrite!
__Don’t get excited too much - there’s still limitation of BLYNK_MAX_SENDBYTES :grinning: (but, you can adjust it)._

@Costas I did see READYBYTES in the docs, but nothing about SENDBYTES especially since the docs also say that virutalWrite() is “effectively” unlimited :wink:

I can happily use the 6 fields with multi-pin. Its working well on a single GET request, but the POST requests fails every time although the body looks fine at requestb.in, oh well. I have a working solution which is a :+1: from me :slight_smile:

SENDBYTES is the same syntax as READBYTES but just the reverse action.

If you don’t have enough SENDBYTES for the url then it doesn’t matter how big you set READBYTES at, it will not return the full details.

Despite the name, GET, will POST updates to the pins. Blynk guys tweaked GET to include POST and it seems to cover everything just fine. Stick with GET.

@russelltomkins @Costas webhook is limited to 5 params.

I extended webhook to 10 params - https://github.com/blynkkk/blynk-server/issues/688
Will be available in next update.


Awesome. Thanks @Dmitriy