barchart adjustments

config.yml

@@ -1,10 +1,10 @@
 runcharts:
-  - title: SEARCH ENGINE RESPONSE TIME (sec)
+- title: SEARCH ENGINE RESPONSE TIME (sec)
   position:
     w: 0
     h: 0
   size:
-      w: 50
+    w: 37
     h: 14
   scale: 3
   items:
@@ -14,14 +14,14 @@ runcharts:
     script: curl -o /dev/null -s -w '%{time_total}'  https://search.yahoo.com
   - label: BING
     script: curl -o /dev/null -s -w '%{time_total}'  https://www.bing.com
-  - title: SEARCH ENGINE RESPONSE TIME 2 (sec)
+- title: SEARCH ENGINE RESPONSE TIME 2 (sec)
   refresh-rate-ms: 5000
   position:
-      w: 0
-      h: 14
+    w: 37
+    h: 0
   size:
-      w: 17
-      h: 10
+    w: 13
+    h: 14
   legend:
     enabled: true
     details: false
@@ -32,7 +32,7 @@ runcharts:
     script: curl -o /dev/null -s -w '%{time_total}'  https://search.yahoo.com
   - label: BING
     script: curl -o /dev/null -s -w '%{time_total}'  https://www.bing.com
-  - title: MONGO COLLECTIONS COUNT
+- title: MONGO COLLECTIONS COUNT
   position:
     w: 17
     h: 14
@@ -46,21 +46,28 @@ runcharts:
   - label: INACTIVE
     script: mongo --quiet --host=localhost blog --eval "db.getCollection('posts').find({status:'INACTIVE'}).itcount()"
 barcharts:
-  - title: ANCHOR CONTEXT EVENTS
-    refresh-rate-ms: 300
+- title: DB EVENTS
+  refresh-rate-ms: 1000
   position:
-      w: 30
-      h: 10
+    w: 0
+    h: 14
   size:
-      w: 16
-      h: 4
+    w: 17
+    h: 10
+  scale: 0
   items:
   - label: ACTIVE
     script: mongo --quiet --host=localhost blog --eval "db.getCollection('posts').find({status:'ACTIVE'}).itcount()"
   - label: INACTIVE
     script: mongo --quiet --host=localhost blog --eval "db.getCollection('posts').find({status:'INACTIVE'}).itcount()"
+  - label: HUACTIVE
+    script: echo 0
+  - label: ACTIVE2
+    script: mongo --quiet --host=localhost blog --eval "db.getCollection('posts').find({status:'ACTIVE'}).itcount()"
+  - label: INACTIVE2
+    script: mongo --quiet --host=localhost blog --eval "db.getCollection('posts').find({status:'INACTIVE'}).itcount()"
 asciiboxes:
-  - title: COUNT
+- title: COUNT
   position:
     w: 34
     h: 14
@@ -68,7 +75,7 @@ asciiboxes:
     w: 16
     h: 4
   script: date +%r
-  - title: MODE
+- title: MODE
   position:
     w: 34
     h: 18

config/config.go

@@ -108,6 +108,12 @@ func (c *Config) findComponent(componentType ComponentType, componentTitle strin
 				return &c.RunCharts[i].ComponentConfig
 			}
 		}
+	case TypeBarChart:
+		for i, component := range c.BarCharts {
+			if component.Title == componentTitle {
+				return &c.BarCharts[i].ComponentConfig
+			}
+		}
 	case TypeAsciiBox:
 		for i, component := range c.AsciiBoxes {
 			if component.Title == componentTitle {

widgets/barchart/barchart.go

@@ -21,12 +21,14 @@ type BarChart struct {
 	bars     []Bar
 	scale    int
 	maxValue float64
+	count    int64
 }
 
 type Bar struct {
 	label string
 	color ui.Color
 	value float64
+	delta float64
 }
 
 func NewBarChart(title string, scale int) *BarChart {
@@ -46,8 +48,9 @@ func (b *BarChart) AddBar(label string, color ui.Color) {
 
 func (b *BarChart) ConsumeSample(sample data.Sample) {
 
-	float, err := strconv.ParseFloat(sample.Value, 64)
+	b.count++
 
+	float, err := strconv.ParseFloat(sample.Value, 64)
 	if err != nil {
 		// TODO visual notification + check sample.Error
 	}
@@ -59,28 +62,50 @@ func (b *BarChart) ConsumeSample(sample data.Sample) {
 		}
 	}
 
+	bar := b.bars[index]
+	bar.delta = float - bar.value
+	bar.value = float
+	b.bars[index] = bar
+
 	if float > b.maxValue {
 		b.maxValue = float
 	}
 
-	bar := b.bars[index]
-	bar.value = float
-	b.bars[index] = bar
+	// normalize bars height once in a while
+	if b.count%500 == 0 {
+		b.reselectMaxValue()
+	}
+}
+
+func (b *BarChart) reselectMaxValue() {
+	maxValue := -math.MaxFloat64
+	for _, bar := range b.bars {
+		if bar.value > maxValue {
+			maxValue = bar.value
+		}
+	}
+	b.maxValue = maxValue
 }
 
 func (b *BarChart) Draw(buf *ui.Buffer) {
 	b.Block.Draw(buf)
 
-	barWidth := b.Inner.Dx() / len(b.bars)
-	barXCoordinate := b.Inner.Min.X
+	barWidth := (b.Inner.Dx() - 2*barIndent - len(b.bars)) / len(b.bars)
+	barXCoordinate := b.Inner.Min.X + barIndent
 
 	labelStyle := ui.NewStyle(console.ColorWhite)
 
 	for _, bar := range b.bars {
+
 		// draw bar
 		height := int((bar.value / b.maxValue) * float64(b.Inner.Dy()-1))
-		for x := barXCoordinate; x < ui.MinInt(barXCoordinate+barWidth, b.Inner.Max.X); x++ {
-			for y := b.Inner.Max.Y - 2; y > (b.Inner.Max.Y-2)-height; y-- {
+		if height <= 1 {
+			height = 2
+		}
+
+		maxYCoordinate := b.Inner.Max.Y - height
+		for x := barXCoordinate; x < ui.MinInt(barXCoordinate+barWidth, b.Inner.Max.X-barIndent); x++ {
+			for y := b.Inner.Max.Y - 2; y >= maxYCoordinate; y-- {
 				c := ui.NewCell(barSymbol, ui.NewStyle(bar.color))
 				buf.SetCell(c, image.Pt(x, y))
 			}
@@ -93,18 +118,20 @@ func (b *BarChart) Draw(buf *ui.Buffer) {
 		buf.SetString(
 			bar.label,
 			labelStyle,
-			image.Pt(labelXCoordinate, b.Inner.Max.Y-1),
-		)
+			image.Pt(labelXCoordinate, b.Inner.Max.Y-1))
 
-		// draw value
-		numberXCoordinate := barXCoordinate + int(float64(barWidth)/2)
-		if numberXCoordinate <= b.Inner.Max.X {
-			buf.SetString(
-				formatValue(bar.value, b.scale),
-				labelStyle,
-				image.Pt(numberXCoordinate, b.Inner.Max.Y-2),
-			)
+		// draw value & delta
+		value := formatValue(bar.value, b.scale)
+		if bar.delta != 0 {
+			value = fmt.Sprintf("%s / %s", value, formatValueWithSign(bar.delta, b.scale))
 		}
+		valueXCoordinate := barXCoordinate +
+			int(float64(barWidth)/2) -
+			int(float64(rw.StringWidth(value))/2)
+		buf.SetString(
+			value,
+			labelStyle,
+			image.Pt(valueXCoordinate, maxYCoordinate-1))
 
 		barXCoordinate += barWidth + barIndent
 	}
@@ -119,3 +146,14 @@ func formatValue(value float64, scale int) string {
 		return fmt.Sprintf(format, value)
 	}
 }
+
+// TODO extract to utils
+func formatValueWithSign(value float64, scale int) string {
+	if value == 0 {
+		return " 0"
+	} else if value > 0 {
+		return "+" + formatValue(value, scale)
+	} else {
+		return formatValue(value, scale)
+	}
+}