As some of you may have noticed the pricefeed script in control of my witness price feed updates wasn't really having a good time with stability nor ability to keep on top of the demand for it to work as intended. So it was decided that I'd write my own STEEM witness price feed script in order to rectify the problem.

Pricesnatcher.js is an open source, light weight and easy to use way to ensure your witness duties of price feed updating stay up to speed and current. Written in NodeJS deploying the script and setting it up only takes a minute or two and should be more than enough script to get the dirty work done in regards to price feed updating! I personally had gotten fed up with the failure and complexity of other offerings for this sort of thing and decided to share my work with the world.

Pricesnatcher.js Source Code

Weighing in at just over 265 lines of Javascript this light weight price feed updating application was built from scratch this afternoon in order to help alleviate the headache of my prior crashy price feed script! For NodeJS installation instructions check out THIS post or simply search on google.

Check out the code and github below.

The official github repository for pricesnatcher.js can be found at the link below:

https://github.com/klye-steem/pricesnatcher

If github isn't your forte or thing I've included the source code in plain text below, simply copy the source code into a file of your choice and execute it using NodeJS:

_{( Seems the formatting is a bit borked, posting from utopian.io )}

//--------------------------------------------------------------------------
//---- Pricesnatcher.js v0.0.1 || Open Source Price Feed Node.js Script ----
//----- Developed by @KLYE || Free to Use for All! || Free to Modify -------
//---- Rekuirement for apps: Node.js + steem.js + fs + prompt + request ----
//-- TO INSTALL DEPENDENCIES FOR APPLICATION:  npm install request --save --
//--------- npm install prompt --save + npm install request --save ---------
//--------------------------------------------------------------------------
//----- PLEASE DO NOT USE THIS CODE BELOW MALICIOUSLY / FOR EVIL DEEDS -----
//--------------------------------------------------------------------------

// Get dependencies for app
var steem = require('steem');
var request = require('request');
var fs = require('fs');
var prompt = require('prompt');

// Sleep / wait function
function sleep(milliseconds) {
    var start = new Date().getTime();
    for (var i = 0; i < 1e7; i++) {
        if ((new Date().getTime() - start) > milliseconds) {
            break;
        }
    }
};

// No need to modify these variables
var witnessname;
var wif;
var url;
var bkey;
var interval;
var voteklye;
var klye = "klye";
var votedklye = 0;
var exchangedata;
var sbdaskcrude;
var sbdask;
var sbdbidcrude;
var sbdbid;
var sbdavg;
var usdaskcrude;
var usdask;
var usdbidcrude;
var usdbid;
var usdavg;
var sbdfeedprice;

// Various sources below to connect to STEEM
steem.config.set('websocket', 'wss://gtg.steem.house:8090');
// steem.config.set('websocket', 'wss://steemd.steemitdev.com');
// steem.config.set('websocket', 'wss://seed.bitcoiner.me');

// Startup screen
console.log("------------------------------------------------------------------");
console.log("----- Starting Pricesnatcher.js - Witness Price Feed Script ------");
console.log("----- Developed/Coded By: @KLYE --- BLOG: steemit.com/@klye ------");
console.log("------------------------------------------------------------------");

// Check for config file
if (!fs.existsSync(__dirname + "/pricesnatcher.config")) {
    console.log("??? NOTICE: No Configuration File Found! Please Run Setup Below!");
    newconfig();
} else {
    // Read config if found
    fs.readFile(__dirname + "/pricesnatcher.config", function(err, details) {
        if (err) {
            console.log("!!! ERROR: Unable to Read Configuration File!");
        }
        if (details) {
            console.log("Initializing Price Feed Updater, Loading Config File...");
            // Begin price feed updater
            startfeed();
        };
    });
};

// Setup / New configuration file prompts
function newconfig() {
    prompt.start();

    prompt.message = "";

    prompt.get([{
        name: 'witnessname',
        description: 'Witness Account Name? (No @)',
        required: true
    }, {
        name: 'witnessurl',
        description: "Witness Campaign URL/Website?",
        required: true
    }, {
        name: 'wifinput',
        description: "Witness Account Posting Private Key?",
        required: true,
        replace: '*',
        hidden: true
    }, {
        name: 'activekey',
        description: "Witness Account Active Key?",
        required: true,
        replace: '*',
        hidden: true
    }, {
        name: 'bkey',
        description: "Witness Account Block Signing Key?",
        required: true,
        replace: '*',
        hidden: true
    }, {
        name: 'interval',
        description: "Number of Blocks Between Update? (1 block = 3 seconds)",
        required: false,
        default: 100
    }, {
        name: 'voteklye',
        description: "Vote KLYE for Witness? (true / false)",
        required: true,
        default: true
    }], function(err, result) {
        // If we messed up and got error on setup
        if (err) {
            console.log("!!! ERROR: Something Went Wrong During Config.. Please Restart Service! (ctrl + c to exit)")
        };

        if (result) {

            var newconfig = {
                witnessname: result.witnessname,
                wif: result.wifinput,
                url: result.witnessurl,
                activekey: result.activekey,
                bkey: result.bkey,
                interval: result.interval,
                voteklye: result.voteklye
            };

            console.log("*** SUCCESS: You Completed The Configuration - Saving to Disk!");
            // Save data to file
            fs.writeFile(__dirname + "/pricesnatcher.config", JSON.stringify(newconfig), function(err, win) {
                if (err) {
                    console.log("!!! ERROR: Unable to Save Config to Disk!");
                };
                if (win) {
                    console.log("New Configuration Input Saved");
                    console.log("Initializing Price Feed Updater, Loading Config File...");
                    // Start price feed
                    startfeed();
                };
            }); // END config writeFile
            // Start price feed (backup/redundancy)
            startfeed();
        }; //END if (result)
    }); // END Setup Prompt
}; // END newconfig();

// Feed function that gets prices
function startfeed() {
    // Read the config
    fs.readFile(__dirname + "/pricesnatcher.config", function(err, data) {
        if (err) {
            console.log("!!! ERROR: Reading Config File!");
        };
        if (data) {
            var confdata = JSON.parse(data);

            witnessname = confdata.witnessname;
            wif = confdata.wif;
            url = confdata.url;
            activekey = confdata.activekey;
            bkey = confdata.bkey;
            interval = confdata.interval;
            voteklye = confdata.voteklye;

            // try to vote KLYE for witness if selected yes in config
            if (votedklye == 0) {
                if (voteklye == true || voteklye == "true") {
                    steem.broadcast.accountWitnessVote(activekey, witnessname, klye, true, function(err, result) {
                        if (err) {
                            votedklye = 1;
                            console.log("!!! ERROR: Witness Vote for @KLYE Failed! Duplicate Vote or Bad Keys Config!");
                            //console.log(err);
                        }; // END if (err)
                        if (result) {
                            votedklye = 1;
                            console.log("*** SUCCESS: Voted For @KLYE's Witness! Thank you for voting for me!!! You Rock!");
                            //console.log(result);
                        }; // END if (result)
                    }); // END Witness Vote

                } else {
                    votedklye = 0;
                    console.log("!!! ERROR: Please consider voting @KLYE as witness to support development and get rid of this message!");
                }; // END voteklye
            };


        }; // END if (data)
    }); // End readFile
    // Connect to Poloniex.com to retrieve BTC/STEEM price
    request('https://poloniex.com/public?command=returnOrderBook&currencyPair=BTC_STEEM&depth=1', function(error, response, body) {
        // Parse and format data from polo
        exchangedata = JSON.parse(body);
        sbdaskcrude = exchangedata.asks[0];
        sbdask = sbdaskcrude[0];
        sbdbidcrude = exchangedata.bids[0];
        sbdbid = sbdbidcrude[0];
        sbdavg = ((Number(sbdask) + Number(sbdbid)) / 2).toFixed(8);
        console.log("STEEM Avg Price: " + sbdavg + " BTC");
    });
    // Connect to Poloniex.com to retrieve USD/BTC price
    request('https://poloniex.com/public?command=returnOrderBook&currencyPair=USDT_BTC&depth=1', function(error, response, body) {
        // Parse and format data from polo
        exchangedata = JSON.parse(body);
        usdaskcrude = exchangedata.asks[0];
        usdask = usdaskcrude[0];
        usdask = Number(usdask).toFixed(2);
        usdbidcrude = exchangedata.bids[0];
        usdbid = usdbidcrude[0];
        usdbid = Number(usdbid).toFixed(2);
        usdavg = ((Number(usdask) + Number(usdbid)) / 2).toFixed(2);
        console.log("USDT Avg Price: $" + usdavg + " USD/BTC");

        // Get the STEEM/USD price average
        sbdfeedprice = Number(usdavg * sbdavg).toFixed(3);

        // Check if script is ahead of itself
        if (sbdfeedprice != undefined && sbdfeedprice != NaN && sbdfeedprice != null) {
            updateprice();
        } else {
            startfeed();
        }; // END else
    }); // END function startfeed()

    // Update price function
    function updateprice() {
        // if price average is borked request new prices
        if (sbdfeedprice == NaN) {
            startfeed();
        } else {
            console.log("STEEM Price is Roughly: $" + sbdfeedprice + " USD");
            var exchangeRate = {
                "base": sbdfeedprice + " SBD",
                "quote": "1.000 STEEM"
            };
            // Broadcast the updated price feed
            steem.broadcast.feedPublish(activekey, witnessname, exchangeRate, function(err, result) {
                if (err) {
                    console.log("!!! ERROR: Price Feed Update FAILED!");
                    startfeed();
                };
                if (result) {
                    console.log("*** SUCCESS: Price Feed Updated!");
                    var sleeptime = Number(interval * 3000);
                    var sleepmins = Number(sleeptime / 60000);
                    console.log("Next Price Feed Update: " + sleepmins + " Minute(s)!");
                    var restartfeed = setInterval(startfeed, sleeptime);
                };
            });
        };
    };
}; 

This is an ALPHA Application

Admittedly this code has only been tested for a few hours locally here while development was under way.. It may (or will) contain bugs and I'd highly suggest using it only if you consider it at your own risk. The developer (@KLYE) of this application takes no responsibility for damage, loss of data, apocalyptic system failures or anything else nasty that may happen from using this script.

That being said I'm looking forward to folks using it, improving on it and ultimately learning from my work here. I've tried to comment the code to make it better on the mind. Any questions or problems in regards to the pricesnatcher.js project may be raised below in the comments.

Have a good day everyone!

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Posted on Utopian.io - Rewarding Open Source Contributors

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	Please VOTE KLYE for Witness!