Tool to generate human readable JSON of Substrate node metadata from a file?

Question

The cli tool subwasm can get the metadata from a live node (url) and output JSON that is human readable. However, to troubleshoot various issues, I need a tool that generates human readable JSON from hex encoded SCALE metadata in a file. i.e. it doesn't go to a live node.

e.g. The hex encoded SCALE data in a JSON-RPC result. It doesn't matter if the tool uses the result data or the whole JSON-RPC json result. I just need it to output it in human readable form.

{"jsonrpc":"2.0","result":"0x6d6574610e3904000c1c73705f636f72651863727970746f2c4163636f756e7449643332000004000401205b75383b2033325d0000040000032000000008000800000503000c08306672616d655f73797374656d2c4163636f756e74496e666f0814496e64657801102c4163636f756e74446174610114001401146e6f6e6365100114496e646578000124636f6e73756d657273100120...etc............

Is there a tool that does this?

Answer 1

Subwasm works on a whole runtime block. It could probably be changed, but I rather created submeta.
You can use it with a stored encoded metadata from an RPC like this:

curl -H "Content-Type: application/json" -d '{"id":1, "jsonrpc":"2.0", "method": "state_getMetadata"}' https://rpc.polkadot.io:443 |\
jq '.result' -r |\
submeta pallets --with-storage

or from a local file:

cat metadata.json | jq metadata.json '.result' -r | submeta pallets --with-storage