Fix namespace of process collector metrics

prometheus/process_collector.go

@@ -44,37 +44,42 @@ func NewProcessCollectorPIDFn(
 	pidFn func() (int, error),
 	namespace string,
 ) Collector {
+	ns := ""
+	if len(namespace) > 0 {
+		ns = namespace + "_"
+	}
+
 	c := processCollector{
 		pidFn:     pidFn,
 		collectFn: func(chan<- Metric) {},
 
 		cpuTotal: NewDesc(
-			namespace+"_process_cpu_seconds_total",
+			ns+"process_cpu_seconds_total",
 			"Total user and system CPU time spent in seconds.",
 			nil, nil,
 		),
 		openFDs: NewDesc(
-			namespace+"_process_open_fds",
+			ns+"process_open_fds",
 			"Number of open file descriptors.",
 			nil, nil,
 		),
 		maxFDs: NewDesc(
-			namespace+"_process_max_fds",
+			ns+"process_max_fds",
 			"Maximum number of open file descriptors.",
 			nil, nil,
 		),
 		vsize: NewDesc(
-			namespace+"_process_virtual_memory_bytes",
+			ns+"process_virtual_memory_bytes",
 			"Virtual memory size in bytes.",
 			nil, nil,
 		),
 		rss: NewDesc(
-			namespace+"_process_resident_memory_bytes",
+			ns+"process_resident_memory_bytes",
 			"Resident memory size in bytes.",
 			nil, nil,
 		),
 		startTime: NewDesc(
-			namespace+"_process_start_time_seconds",
+			ns+"process_start_time_seconds",
 			"Start time of the process since unix epoch in seconds.",
 			nil, nil,
 		),

prometheus/process_collector_test.go

@@ -38,18 +38,18 @@ func TestProcessCollector(t *testing.T) {
 	}
 
 	for _, re := range []*regexp.Regexp{
-		regexp.MustCompile("process_cpu_seconds_total [0-9]"),
-		regexp.MustCompile("process_max_fds [1-9]"),
-		regexp.MustCompile("process_open_fds [1-9]"),
-		regexp.MustCompile("process_virtual_memory_bytes [1-9]"),
-		regexp.MustCompile("process_resident_memory_bytes [1-9]"),
-		regexp.MustCompile("process_start_time_seconds [0-9.]{10,}"),
-		regexp.MustCompile("foobar_process_cpu_seconds_total [0-9]"),
-		regexp.MustCompile("foobar_process_max_fds [1-9]"),
-		regexp.MustCompile("foobar_process_open_fds [1-9]"),
-		regexp.MustCompile("foobar_process_virtual_memory_bytes [1-9]"),
-		regexp.MustCompile("foobar_process_resident_memory_bytes [1-9]"),
-		regexp.MustCompile("foobar_process_start_time_seconds [0-9.]{10,}"),
+		regexp.MustCompile("\nprocess_cpu_seconds_total [0-9]"),
+		regexp.MustCompile("\nprocess_max_fds [1-9]"),
+		regexp.MustCompile("\nprocess_open_fds [1-9]"),
+		regexp.MustCompile("\nprocess_virtual_memory_bytes [1-9]"),
+		regexp.MustCompile("\nprocess_resident_memory_bytes [1-9]"),
+		regexp.MustCompile("\nprocess_start_time_seconds [0-9.]{10,}"),
+		regexp.MustCompile("\nfoobar_process_cpu_seconds_total [0-9]"),
+		regexp.MustCompile("\nfoobar_process_max_fds [1-9]"),
+		regexp.MustCompile("\nfoobar_process_open_fds [1-9]"),
+		regexp.MustCompile("\nfoobar_process_virtual_memory_bytes [1-9]"),
+		regexp.MustCompile("\nfoobar_process_resident_memory_bytes [1-9]"),
+		regexp.MustCompile("\nfoobar_process_start_time_seconds [0-9.]{10,}"),
 	} {
 		if !re.Match(buf.Bytes()) {
 			t.Errorf("want body to match %s\n%s", re, buf.String())