Support Value Conversions

README.md

@@ -60,6 +60,18 @@ modules:
         active: 1      # static value
         count: '{.count}' # dynamic value
         boolean: '{.some_boolean}'
+
+    - name: example_convert
+      type: object
+      path: '{.values[0,1]}'
+      labels:
+        state: '{.state}'
+      values:
+        state: '{.state}'
+      valueconverter:
+        '{.state}': #convert value 'state' into a number
+          active: 1
+          inactive: 2
 
     headers:
       X-Dummy: my-test-header
@@ -70,6 +82,8 @@ Serving HTTP on 0.0.0.0 port 8000 ...
 $ ./json_exporter --config.file examples/config.yml &
 
 $ curl "http://localhost:7979/probe?module=default&target=http://localhost:8000/examples/data.json" | grep ^example
+example_convert_state{state="ACTIVE"} 1
+example_convert_state{state="INACTIVE"} 2
 example_global_value{environment="beta",location="planet-mars"} 1234
 example_value_active{environment="beta",id="id-A"} 1
 example_value_active{environment="beta",id="id-C"} 1

config/config.go

@@ -30,8 +30,11 @@ type Metric struct {
 	EpochTimestamp string
 	Help           string
 	Values         map[string]string
+	ValueConverter ValueConverterType
 }
 
+type ValueConverterType map[string]map[string]string
+
 type ScrapeType string
 
 const (

examples/config.yml

@@ -25,6 +25,19 @@ modules:
         active: 1      # static value
         count: '{.count}' # dynamic value
         boolean: '{.some_boolean}'
+
+    - name: example_convert
+      type: object
+      path: '{.values[0,1]}'
+      labels:
+        state: '{.state}'
+      values:
+        state: '{.state}'
+      valueconverter:
+        '{.state}': #convert value 'state' in JSON into a number
+          active: 1
+          inactive: 2
+
     headers:
       X-Dummy: my-test-header
 

exporter/collector.go

@@ -16,6 +16,7 @@ package exporter
 import (
 	"bytes"
 	"encoding/json"
+	"strings"
 	"time"
 
 	"github.com/go-kit/log"
@@ -38,6 +39,7 @@ type JSONMetric struct {
 	ValueJSONPath          string
 	LabelsJSONPaths        []string
 	ValueType              prometheus.ValueType
+	ValueConverter         config.ValueConverterType
 	EpochTimestampJSONPath string
 }
 
@@ -86,11 +88,14 @@ func (mc JSONMetricCollector) Collect(ch chan<- prometheus.Metric) {
 						continue
 					}
 					value, err := extractValue(mc.Logger, jdata, m.ValueJSONPath, false)
+
 					if err != nil {
 						level.Error(mc.Logger).Log("msg", "Failed to extract value for metric", "path", m.ValueJSONPath, "err", err, "metric", m.Desc)
 						continue
 					}
 
+					value = convertValueIfNeeded(m, value)
+
 					if floatValue, err := SanitizeValue(value); err == nil {
 						metric := prometheus.MustNewConstMetric(
 							m.Desc,
@@ -161,6 +166,19 @@ func extractLabels(logger log.Logger, data []byte, paths []string) []string {
 	return labels
 }
 
+// Returns the conversion of the dynamic value- if it exists in the ValueConverter configuration
+func convertValueIfNeeded(m JSONMetric, value string) string {
+	if m.ValueConverter != nil {
+		if valueMappings, hasPathKey := m.ValueConverter[m.ValueJSONPath]; hasPathKey {
+			value = strings.ToLower(value)
+
+			if _, hasValueKey := valueMappings[value]; hasValueKey {
+				value = valueMappings[value]
+			}
+		}
+	}
+	return value
+}
 func timestampMetric(logger log.Logger, m JSONMetric, data []byte, pm prometheus.Metric) prometheus.Metric {
 	if m.EpochTimestampJSONPath == "" {
 		return pm

exporter/util.go

@@ -118,6 +118,9 @@ func CreateMetricsList(c config.Module) ([]JSONMetric, error) {
 					variableLabels = append(variableLabels, k)
 					variableLabelsValues = append(variableLabelsValues, v)
 				}
+
+				var valueConverters config.ValueConverterType = initializeValueConverter(metric)
+
 				jsonMetric := JSONMetric{
 					Type: config.ObjectScrape,
 					Desc: prometheus.NewDesc(
@@ -130,6 +133,7 @@ func CreateMetricsList(c config.Module) ([]JSONMetric, error) {
 					ValueJSONPath:          valuePath,
 					LabelsJSONPaths:        variableLabelsValues,
 					ValueType:              valueType,
+					ValueConverter:         valueConverters,
 					EpochTimestampJSONPath: metric.EpochTimestamp,
 				}
 				metrics = append(metrics, jsonMetric)
@@ -245,3 +249,22 @@ func renderBody(logger log.Logger, body config.Body, tplValues url.Values) (meth
 	}
 	return
 }
+
+// Initializes and returns a ValueConverter object. nil if there aren't any conversions
+func initializeValueConverter(metric config.Metric) config.ValueConverterType {
+	var valueConverters config.ValueConverterType
+
+	//convert all keys to lowercase
+	if metric.ValueConverter != nil {
+		valueConverters = make(config.ValueConverterType)
+		for valuesKey, innerMap := range metric.ValueConverter {
+			//make the mappings for each value key lowercase
+			valueConverters[valuesKey] = make(map[string]string)
+			for conversionFrom, conversionTo := range innerMap {
+				valueConverters[valuesKey][strings.ToLower(conversionFrom)] = conversionTo
+			}
+		}
+	}
+
+	return valueConverters
+}

test/config/test-converter.yml

@@ -0,0 +1,116 @@
+---
+#the following tests use ./valueconverter.json 
+
+modules:
+  default:
+    metrics:
+    #State should be converted to 1 for the metric value
+    #Test uppercase key
+    - name: test1
+      path: "{$}"
+      help: Testing Single Value Converter on Type Object
+      type: object
+      labels:
+        name: '{.name}'
+      values:
+        state: '{.state}'
+      valueconverter:
+        '{.state}':
+          ACTIVE: 1 
+
+    #State should be converted to 1 for the metric value
+    #Test lowercase key
+    - name: test2
+      path: "{$}"
+      help: Testing Single Value Converter on Type Object
+      type: object
+      labels:
+        name: '{.name}'
+      values:
+        state: '{.state}'
+      valueconverter:
+        '{.state}':
+          active: 1    
+
+    #There should be two JSONs returned: a metric for 'state' with value 1, and a metric with value 12
+    - name: test3
+      path: "{$}"
+      help: Testing Multi Diff Value Converter on Type Object
+      type: object
+      labels:
+        name: '{.name}'
+      values:
+        state: '{.state}'
+        active: 12
+      valueconverter:
+        '{.state}':
+          ACTIVE: 1 
+
+    #Nothing should be returned. This should be an error since 'state' can't be converted to an int
+    - name: test4
+      path: "{$}"
+      help: Testing Value with missing conversion
+      type: object
+      labels:
+        name: '{.name}'
+      values:
+        state: '{.state}'
+
+    #Test nested JSON. It should return with both values but with 12 as the metric value
+    - name: test5
+      path: '{.values[*]}'
+      help: Testing Conversion with Missing value
+      type: object
+      labels:
+        name: '{.name}'
+      values:
+        active: 12
+      valueconverter:
+        '{.state}':
+          ACTIVE: 1 
+
+    #Test nested JSON. 
+    #It should return with both values but 'state' should be converted
+    - name: test6
+      path: '{.values[*]}'
+      help: Testing Value with Multiple Conversions
+      type: object
+      labels:
+        name: '{.name}'
+      values:
+        state: '{.state}'
+      valueconverter:
+        '{.state}':
+          ACTIVE: 1 
+          inactive: 2
+
+    #Test nested JSON. 
+    #However, it should only return with state value
+    #There is a missing key: 'down' in valueconverter
+    - name: test7
+      path: '{.values[*]}'
+      help: Testing Value with Multiple Conversions and Missing Key, Value
+      type: object
+      labels:
+        name: '{.name}'
+      values:
+        state: '{.state}'
+      valueconverter:
+        '{.state}':
+          ACTIVE: 1 
+
+    #Two metrics should be returned
+    #State should be mapped to 1. 
+    #ResponseCode should be 2 because it already has a value in the JSON.
+    - name: test8
+      path: "{$}"
+      help: Testing Multi Diff Value Converter on Type Object
+      type: object
+      labels:
+        name: '{.name}'
+      values:
+        stat: '{.state}'
+        active: '{.responseCode}'
+      valueconverter:
+        '{.state}':
+          ACTIVE: 1 

test/response/test-converter.txt

@@ -0,0 +1,29 @@
+# HELP test1_state Testing Single Value Converter on Type Object
+# TYPE test1_state untyped
+test1_state{name="Test Converter"} 1
+# HELP test2_state Testing Single Value Converter on Type Object
+# TYPE test2_state untyped
+test2_state{name="Test Converter"} 1
+# HELP test3_active Testing Multi Diff Value Converter on Type Object
+# TYPE test3_active untyped
+test3_active{name="Test Converter"} 12
+# HELP test3_state Testing Multi Diff Value Converter on Type Object
+# TYPE test3_state untyped
+test3_state{name="Test Converter"} 1
+# HELP test5_active Testing Conversion with Missing value
+# TYPE test5_active untyped
+test5_active{name="id-A"} 12
+test5_active{name="id-B"} 12
+# HELP test6_state Testing Value with Multiple Conversions
+# TYPE test6_state untyped
+test6_state{name="id-A"} 1
+test6_state{name="id-B"} 2
+# HELP test7_state Testing Value with Multiple Conversions and Missing Key, Value
+# TYPE test7_state untyped
+test7_state{name="id-A"} 1
+# HELP test8_active Testing Multi Diff Value Converter on Type Object
+# TYPE test8_active untyped
+test8_active{name="Test Converter"} 2
+# HELP test8_stat Testing Multi Diff Value Converter on Type Object
+# TYPE test8_stat untyped
+test8_stat{name="Test Converter"} 1

test/serve/test-converter.json

@@ -0,0 +1,16 @@
+{
+    "name": "Test Converter",
+    "state": "ACTIVE",
+    "responseCode": 2,
+    "values": [ 
+        {
+            "name": "id-A",
+            "state": "ACTIVE"
+        },
+        {
+            "name": "id-B",
+            "state": "INACTIVE"
+        }
+    ]
+}
+