SLP Post Office Server
An implementation of the Simple Ledger Postage Protocol
Introduction
It is a server that accepts modified Simple Ledger Payment Protocol transactions, adds stamps (inputs) to it to cover the fee costs, broadcasts the transaction and optionally takes SLP payments for the postage.
It enables all sorts of applications where the user can have only SLP tokens in their wallet and send transactions without the need for BCH as "gas", with the Post Office covering the costs of the transaction.
Current Status
Right now the master branch contains an alpha release. We encourage you to test with small amounts during integration into your own products and provide feedback.
Use at your own risk, there are no guarantees.
More information about the protocol
Setup
Install the required packages and start the server. nvm is not strictly necessary although it makes it easier to use a compatible version of node.
curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.37.2/install.sh | bash
nvm install v14.13.1
nvm use v14.13.1
npm install -g yarn
git clone https://github.com/simpleledger/slp-post-office-server.git
cd slp-post-office-server
cp example.env .env
$(EDITOR) .env
$(EDITOR) src/Config.ts
yarn
yarn start
After this, it will start up and request for you to send some BCH to an address so that the server may generate stamps.
Configuration
Open ./src/Config.ts to list the stamps, priceFeeders, and other options you may want to override or change.
Config.postageRate.stamps describes the different tokens you will accept in your post office.
Config.priceFeeders describes custom price updating mechanisms. These are allowed to overlap in case of downtime of an exchange api.
You will also want to take a look at the example token price feeders in ./src/TokenPriceFeeder/ApiWrapper/ - we have examples for 3 different common price manipulations you may have to do for your token, as well as 3 different exchanges. If you have an example for another exchange please open a PR.
Daemonizing the Server
PM2
You may want to use PM2 to daemonize the server.
pm2 start yarn --interpreter bash --name postoffice -- start
systemd
You can find an example systemd service file in slp-post-office-server.service
Edit this then copy it to /etc/systemd/system
Then run systemctl daemon-reload and systemctl start slp-post-office-server
Wallet Support
As the Post Office is still new there is not wallet support for it yet. If you are a developer and would like to test or inspect the fork of Electron Cash SLP with the Post Office you can find the link below.
- Electron Cash SLP (Development)
Special Thanks
- bchinjim who funded the initial open source post office prototype
License
MIT License