[open-telemetryGH-16344] spanmetricsconnector added tests and fixed s…

…pelling after review

connector/spanmetricsconnector/README.md

@@ -75,7 +75,7 @@ The following settings can be optionally configured:
 
 - `histogram` (default: `explicit`): Use to configure the type of histogram to record
   calculated from spans duration measurements. Must be either `explicit` or `exponential`.
-  - `disable` (default: `false`): Use to disable histogram metrics at all.
+  - `disable` (default: `false`): Disable all histogram metrics.
   - `unit` (default: `ms`): The time unit for recording duration measurements.
   calculated from spans duration measurements. One of either: `ms` or `s`.
   - `explicit`:
@@ -91,7 +91,7 @@ The following settings can be optionally configured:
   If the `name`d attribute is missing in the span, the optional provided `default` is used.
 
   If no `default` is provided, this dimension will be **omitted** from the metric.
-- `exclude_dimensions`: the list of dimensions to be excluded from default. Use to exclude unneeded data from metrics. 
+- `exclude_dimensions`: the list of dimensions to be excluded from the default set of dimensions. Use to exclude unneeded data from metrics. 
 - `dimensions_cache_size` (default: `1000`): the size of cache for storing Dimensions to improve collectors memory usage. Must be a positive number. 
 - `aggregation_temporality` (default: `AGGREGATION_TEMPORALITY_CUMULATIVE`): Defines the aggregation temporality of the generated metrics. 
   One of either `AGGREGATION_TEMPORALITY_CUMULATIVE` or `AGGREGATION_TEMPORALITY_DELTA`.

connector/spanmetricsconnector/connector.go

@@ -387,10 +387,18 @@ func concatDimensionValue(dest *bytes.Buffer, value string, prefixSep bool) {
 // The metric key is a simple concatenation of dimension values, delimited by a null character.
 func (p *connectorImp) buildKey(serviceName string, span ptrace.Span, optionalDims []dimension, resourceAttrs pcommon.Map) metrics.Key {
 	p.keyBuf.Reset()
-	concatDimensionValue(p.keyBuf, serviceName, false)
-	concatDimensionValue(p.keyBuf, span.Name(), true)
-	concatDimensionValue(p.keyBuf, traceutil.SpanKindStr(span.Kind()), true)
-	concatDimensionValue(p.keyBuf, traceutil.StatusCodeStr(span.Status().Code()), true)
+	if !contains(p.config.ExcludeDimensions, serviceNameKey) {
+		concatDimensionValue(p.keyBuf, serviceName, false)
+	}
+	if !contains(p.config.ExcludeDimensions, spanNameKey) {
+		concatDimensionValue(p.keyBuf, span.Name(), true)
+	}
+	if !contains(p.config.ExcludeDimensions, spanKindKey) {
+		concatDimensionValue(p.keyBuf, traceutil.SpanKindStr(span.Kind()), true)
+	}
+	if !contains(p.config.ExcludeDimensions, statusCodeKey) {
+		concatDimensionValue(p.keyBuf, traceutil.StatusCodeStr(span.Status().Code()), true)
+	}
 
 	for _, d := range optionalDims {
 		if v, ok := getDimensionValue(d, span.Attributes(), resourceAttrs); ok {

connector/spanmetricsconnector/connector_test.go

@@ -390,6 +390,32 @@ func TestBuildKeySameServiceNameCharSequence(t *testing.T) {
 	assert.Equal(t, metrics.Key("a\u0000bc\u0000SPAN_KIND_UNSPECIFIED\u0000STATUS_CODE_UNSET"), k1)
 }
 
+func TestBuildKeyExcludeDimensionsAll(t *testing.T) {
+	factory := NewFactory()
+	cfg := factory.CreateDefaultConfig().(*Config)
+	cfg.ExcludeDimensions = []string{"span.kind", "service.name", "span.name", "status.code"}
+	c, err := newConnector(zaptest.NewLogger(t), cfg, nil)
+	require.NoError(t, err)
+
+	span0 := ptrace.NewSpan()
+	span0.SetName("spanName")
+	k0 := c.buildKey("serviceName", span0, nil, pcommon.NewMap())
+	assert.Equal(t, metrics.Key(""), k0)
+}
+
+func TestBuildKeyExcludeWrongDimensions(t *testing.T) {
+	factory := NewFactory()
+	cfg := factory.CreateDefaultConfig().(*Config)
+	cfg.ExcludeDimensions = []string{"span.kind", "service.name.wrong.name", "span.name", "status.code"}
+	c, err := newConnector(zaptest.NewLogger(t), cfg, nil)
+	require.NoError(t, err)
+
+	span0 := ptrace.NewSpan()
+	span0.SetName("spanName")
+	k0 := c.buildKey("serviceName", span0, nil, pcommon.NewMap())
+	assert.Equal(t, metrics.Key("serviceName"), k0)
+}
+
 func TestBuildKeyWithDimensions(t *testing.T) {
 	factory := NewFactory()
 	cfg := factory.CreateDefaultConfig().(*Config)