eth.rb: Possible problem in translating call() params into camelCase requirement

version: 0.5.6

I haven’t been able to send a call transaction to a custom Substrate-based chain with EVM compatibility. I get IOErrors related to the name of the tx params.

Example:

Traceback (most recent call last):
        .
        .
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        3: from /home/arthurmoreira-t14/Code/eth.rb/lib/eth/client.rb:440:in `call_raw'
        2: from /home/arthurmoreira-t14/Code/eth.rb/lib/eth/client.rb:400:in `block (2 levels) in <class:Client>'
        1: from /home/arthurmoreira-t14/Code/eth.rb/lib/eth/client.rb:475:in `send_command'
IOError (unknown field `gas_limit`, expected one of `from`, `to`, `gasPrice`, `maxFeePerGas`, `maxPriorityFeePerGas`, `gas`, `value`, `data`, `nonce`, `accessList`, `type` at line 1 column 12)

Investigating further, I noticed that the JSON fields in the payload look like this:

{:jsonrpc=>"2.0", :method=>"eth_call", :params=>[{:gas_limit=>"0xcf08", :chain_id=>"0x7d8", :data=><sensitive>, :to=>"0xB7d2fFd908ef6B69dA0749600F553923C465c811", :priority_fee=>"0x0", :max_gas_fee=>"0x4a817c800"}, "latest"], :id=>9}

And the response is:

"{\"jsonrpc\":\"2.0\",\"error\":{\"code\":-32602,\"message\":\"unknown field `gas_price`, expected one of `from`, `to`, `gasPrice`, `maxFeePerGas`, `maxPriorityFeePerGas`, `gas`, `value`, `data`, `nonce`, `accessList`, `type` at line 1 column 25\"},\"id\":9}\n"

I was able to make it work by adding a byebug just before sending the request and manually renaming the JSON fields to camelCase, and removing chain_id, adding transaction type: then I can get the correct response:

irb(main):011:0> request.body = "{\"jsonrpc\":\"2.0\",\"method\":\"eth_call\",\"params\":[{\"gas\":\"0xcf08\",\"data\":\"0x\",\"to\":\"0xC6d1eFd908ef6B69dA0749600F553923C465c812\",\"gasPrice\":\"0x0\",\"type\":\"0x00\"},\"latest\"],\"id\":9}"
irb(main):011:0> response = http.request(body)
#<Net::HTTPOK 200 OK readbody=true>
irb(main):011:0> response.body
"{\"jsonrpc\":\"2.0\",\"result\":\"0x0000000000000000000000000000000000000000000000000000000000000000\",\"id\":9}\n"