PriceDataHandler.py

import psycopg2
from config import config
from datetime import datetime
import time, sys, json, datetime
from CoinCap import CoinCap



class PriceDataHandler:

  def __init__(self, coin):
    self.coin = coin
    self.TABLE_NAME = "{}_price_data".format(coin)


  def createTableQuery(self):
    print("Creating table query")
    return "CREATE TABLE {} (day_volume numeric, price numeric, market_cap numeric, time_stamp timestamp without time zone DEFAULT CURRENT_TIMESTAMP);".format(self.TABLE_NAME)
  # Returns query string to insert data into db
  def generateQuery(self, price, marketCap, dayVolume):
    columns = "(day_volume, price, market_cap)"
    values = "({}, {}, {})".format(dayVolume, price, marketCap)
    return "INSERT INTO " + self.TABLE_NAME + " " + columns + " VALUES " + values + ";"

  ## Parses data from API and returns price, day volume, and market cap
  def parseCoinData(self):
    coinCap = CoinCap(self.coin)
    data = coinCap.getData()
    price = data.get('data').get('priceUsd')
    dayVolume = data.get('data').get('volumeUsd24Hr')
    marketCap = data.get('data').get('marketCapUsd')

    return price, dayVolume, marketCap

  def runDataInsertions(self, cursor):
    try:
      price, dayVolume, marketCap = self.parseCoinData()
      print("Time: {} Price: {} 24 hr Volume: {} Market Cap: {}".format(datetime.datetime.now(), price, dayVolume, marketCap))
      insertQuery = self.generateQuery(price, marketCap, dayVolume)
      cursor.execute(insertQuery)
      return None
    except(Exception) as error:
      print("ERROR INSERTING DATA: ", error)
      return error


  # Connects to the db via psycopg2 and inserts data
  def connect(self):
    """ Connect to PGSQL server """
    conn = None

    try:
      params = config()
      print("Connecting to postgres database...")
      conn = psycopg2.connect(**params)
      # create a cursor
      cur = conn.cursor()
      # Generate and execute insertion query
      err = self.runDataInsertions(cur)
      conn.commit() # Commits changes to db
      cur.close() # Closes communication with db
    except(Exception, psycopg2.DatabaseError) as error:
      print("ERROR: ", error)


    finally:
      if err != None:
        cur = conn.cursor()
        cur.execute(self.createTableQuery())
        conn.commit()
        cur.close()
        conn.close()
        self.connect()

      conn.close()
      print('Database connection closed.')


PriceDataHandler("ripple").connect()