vecha 0.0.0

Python library to aid DApp-Server development on VeChain Thor.

- [Contract](#contract)
- [get_events](#get_eventsstart_block_num-to_block_num-event_id)
- [FunctionCoder](#functioncoder)
- [encode_function](#encode_functionfunction_name-args)
- [decode_result](#decode_resultself-function_name-data)
- [EventDecoder](#eventdecoder)
- [decode_event](#decode_eventlog)

# Contract

```py
from vecha import Contract

contract = Contract(endpoint, address, abi_list)
```

**Parameters**:

- **endpoint**: `str`, thor restful server
- **address**: `str`, contract address
- **abi_list**: `List[Dict]`, contract abi

Then you can call the function directly on the contract instance via the function name in abi.

The following function names are built in, so the same name function in the smart contract will not be called.

```
get_events
decode_event
encode_function
decode_result
call
send
_request_events
```

In a smart contract, the function can be a call or a transaction. A transaction must provide private key.

```py
contract.you_name(*args, caller=None, value=0) # a call

contract.you_name(*args, pk, value) # a transaction
```

You can display the transaction as a call, this may help you debug smart contract.

```py
contract.you_name.call(*args, caller=None, value=0)
```

## `get_events(start_block_num, to_block_num, event_id)`

**Parameters**:

- **start_block_num** (optional): `int`, default is from genesis block
- **to_block_num** (optional): `int`, default is to best block
- **event_id** (optional): `str`, the signature of the event you want to filter out, default is all events of this contract

**Returns**:

- `List[Event]`, A list of Events. Event is a `namedtuple`, and it has three fields:
- event.name: `str`
- event.args: `Dict`, actual parameters when the event is emited
- event.block: `int`, the block number when the event is emited

> If you want to parse a log directly, please use [`EventDecoder.decode_event`](#decode_eventlog).<br>
> If you want to get an unsigned transaction data, you can use [`FunctionCoder.encode_function`](#encode_functionfunction_name-args).

# FunctionCoder

```py
from vecha import FunctionCoder

fn_coder = FunctionCoder(*fn_abi_list)
```

## `encode_function(function_name, *args)`

**Parameters**:

- **function_name**: `str`
- **args**: variable-length argument list of actual parameters

**Returns**:

- `str`, the data of a transaction that has not been signed

## `decode_result(self, function_name, data)`


# EventDecoder

```py
from vecha import EventDecoder

ev_decoder = EventDecoder(*event_abi_list)
```

## `decode_event(log)`

**Parameters**:

- **log**: `Dict`, the result of thor restful api `/logs/event`

**Returns**:

- `Event`, Event is a `namedtuple`, and it has three fields:
- event.name: `str`
- event.args: `Dict`, actual parameters when the event is emited
- event.block: `int`, the block number when the event is emited