Add informative messages when transaction fails

[arturgontijo]

If user tries to withdraw an amount that he doesn't have in MPE:

$ snet account withdraw 1000000000000000000000
# gas_price = 1.000000 GWei
Error: {'code': -32000, 'message': 'gas required exceeds allowance or always failing transaction'}
If you want to see full Traceback then run:
snet --print-traceback [parameters]

If user tries to deposit an amount that he doesn't have in his wallet:

$ snet account deposit 10000000000
# gas_price = 1.000000 GWei
    transaction:
        chainId: 3
        ...

Proceed? (y/n): y
Submitting transaction...

    event_summaries:
    -   args:
            owner: '0xA6E06cF37110930D2906e6Ae70bA6224eDED917B'
            spender: '0x7E6366Fbe3bdfCE3C906667911FC5237Cc96BD08'
            value: 1000000000000000000
        event: Approval
    ...

# gas_price = 1.000000 GWei
Error: {'code': -32000, 'message': 'gas required exceeds allowance or always failing transaction'}
If you want to see full Traceback then run:
snet --print-traceback [parameters]

(in this case we must avoid the Approval transaction too, not only adding a message...)

If user tries to publish an already published service:

$ snet service publish snet example-service
# gas_price = 1.000000 GWei
Error: {'code': -32000, 'message': 'gas required exceeds allowance or always failing transaction'}
If you want to see full Traceback then run:
snet --print-traceback [parameters]

If user tries to delete a service from other user:

$ snet service delete snet example-service
# gas_price = 1.000000 GWei
Error: {'code': -32000, 'message': 'gas required exceeds allowance or always failing transaction'}
If you want to see full Traceback then run:
snet --print-traceback [parameters]

Will check all commands but first we need to agree on how to deliver this to the users... I did this, in a friendly way, in the snet organization commands, like:

$ snet organization add-members snet 0xA6E06cF37110930D2906e6Ae70bA6224eDED917B
Creating transaction to add 1 members into organization snet...

# gas_price = 1.000000 GWei

Transaction error!
HINT: Check if you are the owner of snet

Error: {'code': -32000, 'message': 'gas required exceeds allowance or always failing transaction'}
If you want to see full Traceback then run:
snet --print-traceback [parameters]

What do you guys think about how we should warn/inform/show messages to the users?

[astroseger]

@arturgontijo I would propose slightly different approach.

We should check for possible errors before making transaction.

For example: In snet organization add-members we should check that current identity is the owner of the given organization and we should fail with clear message ("you are not the owner of ...."). I think it is better then the current "HINT" behavior because it might be misleading (if the real reason of the failure is different).

The same for all examples @arturgontijo has mentioned.

[arturgontijo]

Agree!