Trim spaces from values

cmd/main_test.go

@@ -138,6 +138,7 @@ func TestCorrectResponse(t *testing.T) {
 	}{
 		{"../test/config/good.yml", "/serve/good.json", "../test/response/good.txt", true},
 		{"../test/config/good.yml", "/serve/repeat-metric.json", "../test/response/good.txt", false},
+		{"../test/config/trim.yml", "/serve/trim.json", "../test/response/good.txt", false},
 	}
 
 	target := httptest.NewServer(http.FileServer(http.Dir("../test")))

examples/config.yml

@@ -43,6 +43,18 @@ modules:
       values:
         population: '{ .population }'
 
+  trim:
+    metrics:
+    - name: animal
+      type: object
+      help: Example of top-level lists in a separate module
+      path: '{ [*] }'
+      labels:
+        name: '{ .noun }'
+        predator: '{ .predator }'
+      values:
+        population: '{ .population }'
+
     ## HTTP connection configurations can be set in 'modules.<module_name>.http_client_config' field. For full http client config parameters, ref: https://pkg.go.dev/github.com/prometheus/common/config?tab=doc#HTTPClientConfig
     #
     # http_client_config:

examples/trim-data.json

@@ -0,0 +1,25 @@
+{
+    "counter": 1234,
+    "timestamp": 1657568506,
+    "values": [
+        {
+            "id": "   id-A",
+            "count": 1,
+            "some_boolean": true,
+            "state": "   ACTIVE"
+        },
+        {
+            "id": "id-B",
+            "count": 2,
+            "some_boolean": true,
+            "state": "   INACTIVE"
+        },
+        {
+            "id": "id-C",
+            "count": 3,
+            "some_boolean": false,
+            "state": "   ACTIVE"
+        }
+    ],
+    "location": "mars    "
+}

exporter/collector.go

@@ -17,6 +17,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"log/slog"
+	"strings"
 	"time"
 
 	"github.com/prometheus-community/json_exporter/config"
@@ -144,7 +145,7 @@ func extractValue(logger *slog.Logger, data []byte, path string, enableJSONOutpu
 		return res, nil
 	}
 
-	return buf.String(), nil
+	return strings.TrimSpace(buf.String()), nil
 }
 
 // Returns the list of labels created from the list of provided json paths

test/config/trim.yml

@@ -0,0 +1,26 @@
+---
+modules:
+  default:
+    metrics:
+    - name: example_global_value
+      path: "{ .counter }"
+      help: Example of a top-level global value scrape in the json
+      valuetype: gauge
+      labels:
+        environment: beta # static label
+        location: "planet-{.location}"          # dynamic label
+
+    - name: example_value_trim
+      type: object
+      help: Example of sub-level value scrapes from a json
+      path: '{.values[?(@.state == "ACTIVE")]}'
+      valuetype: counter
+      trimvalues: true
+      labels:
+        environment: beta # static label
+        id: '{.id}'       # dynamic label
+      values:
+        active: 1         # static value
+        count: '{.count}' # dynamic value
+        boolean: '{.some_boolean}'
+        float: '{.float}'

test/response/trim.txt

@@ -0,0 +1,19 @@
+# HELP example_global_value Example of a top-level global value scrape in the json
+# TYPE example_global_value gauge
+example_global_value{environment="beta",location="planet-mars"} 1234
+# HELP example_value_trim_active Example of sub-level value scrapes from a json
+# TYPE example_value_trim_active counter
+example_value_trim_active{environment="beta",id="id-A"} 1
+example_value_trim_active{environment="beta",id="id-C"} 1
+# HELP example_value_trim_boolean Example of sub-level value scrapes from a json
+# TYPE example_value_trim_boolean counter
+example_value_trim_boolean{environment="beta",id="id-A"} 1
+example_value_trim_boolean{environment="beta",id="id-C"} 0
+# HELP example_value_trim_count Example of sub-level value scrapes from a json
+# TYPE example_value_trim_count counter
+example_value_trim_count{environment="beta",id="id-A"} 1
+example_value_trim_count{environment="beta",id="id-C"} 3
+# HELP example_value_count Example of sub-level value scrapes from a json
+# TYPE example_value_count counter
+example_value_float{environment="beta",id="id-A"} 3.1415
+example_value_float{environment="beta",id="id-C"} 3.14

test/serve/trim.json

@@ -0,0 +1,27 @@
+{
+    "counter": 1234,
+    "values": [
+        {
+            "id": "id-A",
+            "count": 1,
+            "some_boolean": true,
+            "state": "    ACTIVE   ",
+            "float": "   3.1415   "
+        },
+        {
+            "id": "id-B",
+            "count": 2,
+            "some_boolean": true,
+            "state": "    INACTIVE",
+            "float": "   3.141   "
+        },
+        {
+            "id": "id-C",
+            "count": 3,
+            "some_boolean": false,
+            "state": "   ACTIVE",
+            "float": "   3.14"
+        }
+    ],
+    "location": "    mars   "
+}