using canonical Python requests --> {"code":-32700,"message":"Parse error"} about substrate-node-template HOT 7 CLOSED

The issue is single vs double quotes in the request, not with python vs javascript. I can reproduce your results using curl.

$ curl -H 'Content-Type: application/json' --data '{ "jsonrpc":"2.0", "method":"author_rotateKeys", "id":1 }' https://dev-node.substrate.dev:9933

{"jsonrpc":"2.0","result":"0xb2e193c900159b6cf86b2dedea550030c9c912a160e1996decbd09159527d92f882739012a3bb9803e7ee4ffd72a290436735dbdd20a463db2736365c112597b9a2eca667dedde4a32180b2c6bbecb033cc7640f0683da37f3b070c3f72abb2a","id":1}


$ curl -H 'Content-Type: application/json' --data "{ 'jsonrpc':'2.0', 'method':'author_rotateKeys', 'id':1 }" https://dev-node.substrate.dev:9933

{"jsonrpc":"2.0","error":{"code":-32700,"message":"Parse error"},"id":null}

Standby and I'll dig deeper.

from substrate-node-template.

Thanks. So it's like this:

• r = requests.post(url, data=json.dumps(payload), headers=headers)

I don't remember to have ever needed to do that, with any request call, ever. I have just looked up older code ... and found the difference. It was probably because I had always called it with json=payload, i.e. this works too:

• r = requests.post(url, json=payload, headers=headers)

Thank you very much. And sorry to have bothered you with this.

from substrate-node-template.

Looks like the tutorial that you are taking a look to could not have the latest changes. It is maintained by @shawntabrizi
link: https://www.shawntabrizi.com/substrate/querying-substrate-storage-via-rpc/

from substrate-node-template.

Have you tried by following the original tutorial?
I would suggest to try it on JavaScript and then see if you can replicate the issue.

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I would suggest you try it out:

pip3 install requests
python3 substrate_RPC-flaw.py 

I suppose, it comes from different stringification of dictionaries of JS vs Python??

The substrate RPC server should be language agnostic, and not force people to use JS, no?

Yes, this place HERE might be the wrong place. I guess it's the substrate core devs` job.

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I can reproduce your results using curl.

Oh yes. Of course, that is even simpler. Well done.

It has to do with Python versus Javascript, because (while it's probably different for JS ??) ... the default way for Python to stringify its dictionaries seems to favor singlequotes '.

While the substrate RPC server is only happy with doublequotes " ??

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The documentation for your preferred requests module explains what to do when the RPC you're calling needs valid JSON. https://requests.readthedocs.io/en/latest/user/quickstart/#more-complicated-post-requests (Third code snippet).

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