add "psar" indicator

Author: Haehnchen

.idea/crypto-trading-bot.iml

@@ -133,7 +133,7 @@ function executeTulindIndicator(source, indicator, tulindOptions) {
 
 module.exports = {
   // indicators which source is Candles
-  sourceCandle: ['cci', 'pivot_points_high_low', 'obv', 'ao', 'mfi', 'stoch', 'vwma', 'atr', 'adx', 'volume_profile', 'volume_by_price', 'ichimoku_cloud', 'zigzag', 'wicked', 'heikin_ashi'],
+  sourceCandle: ['cci', 'pivot_points_high_low', 'obv', 'ao', 'mfi', 'stoch', 'vwma', 'atr', 'adx', 'volume_profile', 'volume_by_price', 'ichimoku_cloud', 'zigzag', 'wicked', 'heikin_ashi', 'psar'],
 
   bb: (source, indicator) => 
     executeTulindIndicator(source, indicator, {
@@ -293,6 +293,28 @@ module.exports = {
     });
   },
 
+  psar: function(source, indicator) {
+    return new Promise(resolve => {
+      const { options = {} } = indicator;
+      const { step = 0.02, max = 0.2 } = options;
+
+      const input = {
+        high: [],
+        low: [],
+        step: step,
+        max: max
+      };
+
+      source.forEach(candle => {
+        input.high.push(candle.high)
+        input.low.push(candle.low)
+      })
+
+      const { PSAR } = require('technicalindicators');
+      resolve({ [indicator.key]: new PSAR(input).getResult() });
+    });
+  },
+
   heikin_ashi: function(source, indicator) {
     return new Promise(resolve => {
 

.idea/jsLibraryMappings.xml

@@ -151,6 +151,14 @@ describe('#technical_analysis for candles', () => {
       {
         indicator: 'ichimoku_cloud',
         key: 'ichimoku_cloud'
+      },
+      {
+        indicator: 'psar',
+        key: 'psar',
+        options: {
+          step: 0.01,
+          max: 0.011
+        }
       }
     ]);
 
@@ -228,6 +236,8 @@ describe('#technical_analysis for candles', () => {
 
     assert.equal(result.adx[0] > 0, true);
 
+    assert.equal(result.psar[0], 8144.5);
+
     const volumeByPrice = result.volume_by_price[0][0];
 
     assert.equal(volumeByPrice.low > 0, true);