Lightsteem 0.0.4 - Broadcasting support

Lightsteem is a lightweight python client for STEEM blockchain. I have been working on a couple of things after the initial release and here is the new version.

Installation / Updating

---

If you don't have lightsteem yet:

$ pip install lighsteem

if you have it already:

$ pip install lightsteem --upgrade

Broadcasting Support and Transaction signing

---

You can now push transactions to the blockchain.

Example: Broadcasting a witness vote

from lightsteem.client import Client
from lightsteem.datastructures import Operation

c = Client(
    keys=["<active_private_key>",])

op = Operation('account_witness_vote', {
        'account': '<your_account>',
        'witness': 'emrebeyler',
        'approve': True,
    })

c.broadcast(op)

The Operation tuple is a simple named tuple where the first parameter is the operation name, and the second parameter is the operation value on STEEM blockchain specs.

Example: Creating a Transfer

from lightsteem.client import Client
from lightsteem.broadcast.transaction_builder import TransactionBuilder
from lightsteem.datastructures import Operation

import logging

c = Client(
    keys=["<active_key>",])

op = Operation('transfer', {
        'from': 'emrebeyler',
        'to': 'utopian-io',
        'amount': '0.001 SBD',
        'memo': 'test1!'
})
c.broadcast(ops)

For the reference, transaction signing stuff is derived from steem-python with little changes. Serializers are not ported, instead, I have used get_transaction_hex call in steemd.

Broadcasting multiple operations

---

Just sending an iterable to the client.broadcast is enough.

Example: Creating multiple transfers in one transaction

from lightsteem.client import Client
from lightsteem.datastructures import Operation

c = Client(
    keys=["<active_key>",])

ops = [
    Operation('transfer', {
        'from': 'emrebeyler',
        'to': 'utopian-io',
        'amount': '0.001 SBD',
        'memo': 'test1!'
    }),
    Operation('transfer', {
        'from': 'emrebeyler',
        'to': 'steemhunt',
        'amount': '0.001 SBD',
        'memo': 'test2!'
    }),
]
c.broadcast(ops)

Retry and Failover changes on RPC calls

---

First implementation on retry/failover was lacking timeout handling and had a linear retry logic.

With this version, if a node returns an HTTP status between *400 and 600 or had a timeout, client retries up to 5 times the same node with an exponential backoff algorithm.

If there is no success, switches to the next available node.

Unit tests and Continuous Integration

---

Added initial unit tests and setup TravisCI. Now, every commit, pull request will have a custom build checks for the unit tests results.

Code coverage is not the best at the moment, but it will be better.

Changeset

---

Lots of small things are also changed.

All changes can be seen in this compare page.

Roadmap

---

With the transaction signing, I want to focus on unit tests. One big missing thing is also documentation and tutorials for people to use Lightsteem.

Contributing

---

I have a separate Discord server for Lightsteem. If you have any ideas, or if you want to add a new feature, let's collaborate here. :)

Notice

---

This library is under development and may include bugs. If you plan to use it on production, please do your own audit beforehand.