add simple YAML config tests

mapper.go

@@ -143,6 +143,21 @@ func (m *metricMapper) initFromYAMLString(fileContents string) error {
 			return fmt.Errorf("invalid match: %s", currentMapping.Match)
 		}
 
+		// check that label is correct
+		for k, v := range currentMapping.Labels {
+			label := fmt.Sprintf("%s=%q", k, v)
+			if len(labelLineRE.FindStringSubmatch(label)) != 3 {
+				return fmt.Errorf("invalid label: %s: %s", k, v)
+			}
+			if k == "name" && !metricNameRE.MatchString(v) {
+				return fmt.Errorf("metric name '%s' doesn't match regex '%s'", v, metricNameRE)
+			}
+		}
+
+		if _, ok := currentMapping.Labels["name"]; !ok {
+			return fmt.Errorf("Line %d: metric mapping didn't set a metric name", i)
+		}
+
 		// Translate the glob-style metric match line into a proper regex that we
 		// can use to match metrics later on.
 		metricRe := strings.Replace(currentMapping.Match, ".", "\\.", -1)
@@ -156,6 +171,7 @@ func (m *metricMapper) initFromYAMLString(fileContents string) error {
 		if currentMapping.Buckets == nil || len(currentMapping.Buckets) == 0 {
 			currentMapping.Buckets = n.Defaults.Buckets
 		}
+
 	}
 
 	m.mutex.Lock()

mapper_test.go

@@ -28,30 +28,30 @@ func TestMetricMapper(t *testing.T) {
 		// Config with several mapping definitions.
 		{
 			config: `
-				# this is a comment
-				# this is another
-				test.dispatcher.*.*.*
-				name="dispatch_events"
-				processor="$1"
-				action="$2"
-				result="$3"
-				# here is a third
-				job="test_dispatcher"
+  # this is a comment
+  # this is another
+  test.dispatcher.*.*.*
+  name="dispatch_events"
+  processor="$1"
+  action="$2"
+  result="$3"
+  # here is a third
+  job="test_dispatcher"
 
-				test.my-dispatch-host01.name.dispatcher.*.*.*
-				name="host_dispatch_events"
-				processor="$1"
-				action="$2"
-				result="$3"
-				job="test_dispatcher"
+  test.my-dispatch-host01.name.dispatcher.*.*.*
+  name="host_dispatch_events"
+  processor="$1"
+  action="$2"
+  result="$3"
+  job="test_dispatcher"
 
-				*.*
-				name="catchall"
-				first="$1"
-				second="$2"
-				third="$3"
-				job="$1-$2-$3"
-			`,
+  *.*
+  name="catchall"
+  first="$1"
+  second="$2"
+  third="$3"
+  job="$1-$2-$3"
+  `,
 			mappings: map[string]map[string]string{
 				"test.dispatcher.FooProcessor.send.succeeded": map[string]string{
 					"name":      "dispatch_events",
@@ -80,10 +80,10 @@ func TestMetricMapper(t *testing.T) {
 		// Config with bad regex reference.
 		{
 			config: `
-				test.*
-				name="name"
-				label="$1_foo"
-			`,
+  test.*
+  name="name"
+  label="$1_foo"
+  `,
 			mappings: map[string]map[string]string{
 				"test.a": map[string]string{
 					"name":  "name",
@@ -94,10 +94,10 @@ func TestMetricMapper(t *testing.T) {
 		// Config with good regex reference.
 		{
 			config: `
-				test.*
-				name="name"
-				label="${1}_foo"
-			`,
+  test.*
+  name="name"
+  label="${1}_foo"
+  `,
 			mappings: map[string]map[string]string{
 				"test.a": map[string]string{
 					"name":  "name",
@@ -108,53 +108,53 @@ func TestMetricMapper(t *testing.T) {
 		// Config with bad metric line.
 		{
 			config: `
-				bad--metric-line.*.*
-				name="foo"
-			`,
+  bad--metric-line.*.*
+  name="foo"
+  `,
 			configBad: true,
 		},
 		// Config with bad label line.
 		{
 			config: `
-				test.*.*
-				name=foo
-			`,
+  test.*.*
+  name=foo
+  `,
 			configBad: true,
 		},
 		// Config with bad label line.
 		{
 			config: `
-				test.*.*
-				name="foo-name"
-			`,
+  test.*.*
+  name="foo-name"
+  `,
 			configBad: true,
 		},
 		// Config with bad metric name.
 		{
 			config: `
-				test.*.*
-				name="0foo"
-			`,
+  test.*.*
+  name="0foo"
+  `,
 			configBad: true,
 		},
 		// A single mapping config without a terminating newline.
 		{
 			config: `
-				test.*
-				name="name"
-				label="foo"`,
+  test.*
+  name="name"
+  label="foo"`,
 			configBad: true,
 		},
 		// Multiple mapping configs and no terminating newline.
 		{
 			config: `
-				test.bar
-				name="name_bar"
-				label="foo"
+  test.bar
+  name="name_bar"
+  label="foo"
 
-				test.foo
-				name="name_foo"
-				label="bar"`,
+  test.foo
+  name="name_foo"
+  label="bar"`,
 			configBad: true,
 		},
 	}
@@ -185,3 +185,158 @@ func TestMetricMapper(t *testing.T) {
 		}
 	}
 }
+
+func TestMetricMapperYAML(t *testing.T) {
+	scenarios := []struct {
+		config    string
+		configBad bool
+		mappings  map[string]map[string]string
+	}{
+		// Empty config.
+		{},
+		// Config with several mapping definitions.
+		{
+			config: `---
+mappings:
+- match: test.dispatcher.*.*.*
+  labels: 
+    name: "dispatch_events"
+    processor: "$1"
+    action: "$2"
+    result: "$3"
+    job: "test_dispatcher"
+- match: test.my-dispatch-host01.name.dispatcher.*.*.*
+  labels:
+    name: "host_dispatch_events"
+    processor: "$1"
+    action: "$2"
+    result: "$3"
+    job: "test_dispatcher"
+- match: "*.*"
+  labels:
+    name: "catchall"
+    first: "$1"
+    second: "$2"
+    third: "$3"
+    job: "$1-$2-$3"
+  `,
+			mappings: map[string]map[string]string{
+				"test.dispatcher.FooProcessor.send.succeeded": map[string]string{
+					"name":      "dispatch_events",
+					"processor": "FooProcessor",
+					"action":    "send",
+					"result":    "succeeded",
+					"job":       "test_dispatcher",
+				},
+				"test.my-dispatch-host01.name.dispatcher.FooProcessor.send.succeeded": map[string]string{
+					"name":      "host_dispatch_events",
+					"processor": "FooProcessor",
+					"action":    "send",
+					"result":    "succeeded",
+					"job":       "test_dispatcher",
+				},
+				"foo.bar": map[string]string{
+					"name":   "catchall",
+					"first":  "foo",
+					"second": "bar",
+					"third":  "",
+					"job":    "foo-bar-",
+				},
+				"foo.bar.baz": map[string]string{},
+			},
+		},
+		// Config with bad regex reference.
+		{
+			config: `---
+mappings:
+- match: test.*
+  labels:
+    name: "name"
+    label: "$1_foo"
+  `,
+			mappings: map[string]map[string]string{
+				"test.a": map[string]string{
+					"name":  "name",
+					"label": "",
+				},
+			},
+		},
+		// Config with good regex reference.
+		{
+			config: `
+mappings:
+- match: test.*
+  labels:
+    name: "name"
+    label: "${1}_foo"
+  `,
+			mappings: map[string]map[string]string{
+				"test.a": map[string]string{
+					"name":  "name",
+					"label": "a_foo",
+				},
+			},
+		},
+		// Config with bad metric line.
+		{
+			config: `---
+mappings:
+- match: bad--metric-line.*.*
+  labels:
+    name: "foo"
+  `,
+			configBad: true,
+		},
+		// Config with bad metric name.
+		{
+			config: `---
+mappings:
+- match: test.*.*
+  labels:
+    name: "0foo"
+  `,
+			configBad: true,
+		},
+		// Config with no metric name.
+		{
+			config: `---
+mappings:
+- match: test.*.*
+  labels:
+    this: "$1"
+  `,
+			configBad: true,
+		},
+		// Config with no mappings.
+		{
+			config:   ``,
+			mappings: map[string]map[string]string{},
+		},
+	}
+
+	mapper := metricMapper{}
+	for i, scenario := range scenarios {
+		err := mapper.initFromYAMLString(scenario.config)
+		if err != nil && !scenario.configBad {
+			t.Fatalf("%d. Config load error: %s %s", i, scenario.config, err)
+		}
+		if err == nil && scenario.configBad {
+			t.Fatalf("%d. Expected bad config, but loaded ok: %s", i, scenario.config)
+		}
+
+		for metric, mapping := range scenario.mappings {
+			_, labels, present := mapper.getMapping(metric)
+			if len(labels) == 0 && present {
+				t.Fatalf("%d.%q: Expected metric to not be present", i, metric)
+			}
+			if len(labels) != len(mapping) {
+				t.Fatalf("%d.%q: Expected %d labels, got %d", i, metric, len(mapping), len(labels))
+			}
+			for label, value := range labels {
+				if mapping[label] != value {
+					t.Fatalf("%d.%q: Expected labels %v, got %v", i, metric, mapping, labels)
+				}
+			}
+		}
+	}
+}