market-faker v0.1.0

market-faker provides simulated financial market data.

Motivation

Legitimate external sources for financial instruments can incur problems related to API key expiry, restrictive hours of availability, data limits, service downtime, and fees.

Usage

yarn add market-faker

import market from 'market-faker'

const foo = market({
  name: 'Foobar PLC',
  opening: 1271.1,
})

console.log(foo.snapshot.sell)
// -> 1271.2

foo.subscribe(market => {
  console.log(market.sell)
  // -> 1270.6
})

Characteristics of a Market

• Prices tick at random intervals
• Only the properties that have changed come back in the subscribe handlers
• The initial market properties are available as market.snapshot
• buy price and sell price are a small but random distance apart. They start either side of the opening
• change is the difference from the buy and the opening
• changePercentage shows the change as a percentage of the opening
• high is the maximum a buy price has been
• low is the lowest the sell price has been
• Historical data for any existing property of the market can be specified with a history object. e.g. The following would include the last 3 buy prices in the subscribable data:

const foo = market({
  name: 'Foobar PLC',
  opening: 1271.1,
  history: {
    buy: 3,
  },
})

foo.subscribe(market => {
  console.log(market.history.buy)
  // -> [1270.6, 1271.1, 1269.3]
})