First commit

Signed-off-by: Remy Chantenay <[email protected]>

.github/workflows/main.yaml

@@ -16,10 +16,10 @@ jobs:
     - name: Set up Go
       uses: actions/setup-go@v4
       with:
-        go-version: '1.21'
+        go-version: '1.23'
 
     - name: Install golangci-lint
-      run: go install github.com/golangci/golangci-lint/cmd/golangci-lint@v1.54.2
+      run: go install github.com/golangci/golangci-lint/cmd/golangci-lint@v1.61.0
 
     - name: Install govulncheck
       run: go install golang.org/x/vuln/cmd/govulncheck@latest
@@ -33,7 +33,3 @@ jobs:
     - name: Testing
       run: make test
 
-    - name: Upload coverage reports to Codecov
-      uses: codecov/codecov-action@v3
-      env:
-        CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}

README.md

@@ -2,12 +2,66 @@
 Simple package that extracts OpenTelemetry span attributes from a struct based on tags.
 
 ## Shortcomings
-- Do not support embedded structs.
+- Does not support embedded structs.
+
+## Usage
+### Span Attributes
+```go
+package main
+
+import (
+	"context"
+
+	"go.opentelemetry.io/otel/trace"
+
+	oteltag "github.com/remychantenay/otel-tag"
+)
+
+type User struct {
+	ID        string `otel:"app.user.id"`
+	Username  string `otel:"app.user.username"`
+	IsPremium bool   `otel:"app.user.premium"`
+	Website   string `otel:"app.user.website,omitempty"`
+	Bio       string `otel:"-"`
+}
+
+func main() {
+	_, span := tracer.Start(context.Background(), "someOperation",
+		trace.WithAttributes(oteltag.SpanAttributes(m)...),
+	)
+	defer span.End()
+}
+```
+
+### Baggage Members
+```go
+package main
+
+import (
+	"context"
+
+	"go.opentelemetry.io/otel/baggage"
+
+	oteltag "github.com/remychantenay/otel-tag"
+)
+
+type User struct {
+	ID        string `otel:"app.user.id"`
+	Username  string `otel:"app.user.username"`
+	IsPremium bool   `otel:"app.user.premium"`
+	Website   string `otel:"app.user.website,omitempty"`
+	Bio       string `otel:"-"`
+}
+
+func main() {
+	members := oteltag.BaggageMembers(m)
+	bag, _ := baggage.New(members...)
+	ctx := baggage.ContextWithBaggage(context.Background(), bag)
+
+	_, span := tracer.Start(ctx, "someOperation")
+	defer span.End()
+}
+```
 
 ## License
 Apache License Version 2.0
-
-TODO
-- Shit! What about attribute name prefix???! Init?
-- Remove t.Log() calls in tests
-- Complete README.md with example

baggage.go

@@ -24,15 +24,15 @@ func BaggageMembers(res any) []baggage.Member {
 	for i := 0; i < fieldCount; i++ {
 		tag := internal.ExtractTag(structValue, i)
 
-		if len(tag) == 0 || tag == valIgnore {
+		if len(tag) == 0 || tag == flagIgnore {
 			continue
 		}
 
 		var omitEmpty bool
 		before, after, found := strings.Cut(tag, ",")
 		if found {
 			tag = before
-			if after == valOmitEmpty {
+			if after == flagOmitEmpty {
 				omitEmpty = true
 			}
 		}

baggage_test.go

@@ -37,10 +37,6 @@ func TestBaggageMembers(t *testing.T) {
 		if memberCount != wantMemberCount {
 			t.Errorf("\ngot %d members\nwant %d", memberCount, wantMemberCount)
 		}
-
-		for i := range bag.Members() {
-			t.Log(bag.Members()[i].Key())
-		}
 	})
 
 	t.Run("when zero values and omitted - should not add members to baggage", func(t *testing.T) {
@@ -77,9 +73,25 @@ func TestBaggageMembers(t *testing.T) {
 		if memberCount != wantMemberCount {
 			t.Errorf("\ngot %d members\nwant %d", memberCount, wantMemberCount)
 		}
+	})
+
+	t.Run("when fields are ignored - should not add members to baggage", func(t *testing.T) {
+		const wantMemberCount = 0
+
+		m := struct {
+			ValStrIgnored string `otel:"-"`
+		}{
+			ValStrIgnored: "a_string",
+		}
 
-		for i := range bag.Members() {
-			t.Log(bag.Members()[i].Key())
+		members := oteltag.BaggageMembers(m)
+		bag, _ := baggage.New(members...)
+		ctx := baggage.ContextWithBaggage(context.Background(), bag)
+		bag = baggage.FromContext(ctx)
+
+		memberCount := len(bag.Members())
+		if memberCount != wantMemberCount {
+			t.Errorf("\ngot %d members\nwant %d", memberCount, wantMemberCount)
 		}
 	})
 }

main.go

@@ -1,6 +1,6 @@
 package oteltag
 
 const (
-	valIgnore    = "-"
-	valOmitEmpty = "omitempty"
+	flagIgnore    = "-"
+	flagOmitEmpty = "omitempty"
 )

span.go

@@ -24,15 +24,15 @@ func SpanAttributes(res any) []attribute.KeyValue {
 	for i := 0; i < fieldCount; i++ {
 		tag := internal.ExtractTag(structValue, i)
 
-		if len(tag) == 0 || tag == valIgnore {
+		if len(tag) == 0 || tag == flagIgnore {
 			continue
 		}
 
 		var omitEmpty bool
 		before, after, found := strings.Cut(tag, ",")
 		if found {
 			tag = before
-			if after == valOmitEmpty {
+			if after == flagOmitEmpty {
 				omitEmpty = true
 			}
 		}

span_test.go

@@ -63,10 +63,6 @@ func TestSpanAttributes(t *testing.T) {
 		if attrCount != expectedAttributeCount {
 			t.Errorf("\ngot %d attributes\nwant %d", attrCount, expectedAttributeCount)
 		}
-
-		// for i := range spans[0].Attributes() {
-		// 	t.Log(spans[0].Attributes()[i].Value)
-		// }
 	})
 
 	t.Run("when zero values and omitted - should not add attributes to span", func(t *testing.T) {
@@ -131,9 +127,39 @@ func TestSpanAttributes(t *testing.T) {
 		if attrCount != expectedAttributeCount {
 			t.Errorf("\ngot %d attributes\nwant %d", attrCount, expectedAttributeCount)
 		}
+	})
+
+	t.Run("when fields are ignored - should not add attributes to span", func(t *testing.T) {
+		const (
+			wantSpanCount          = 1
+			expectedAttributeCount = 0
+		)
+
+		spanRecorder, tracer := setupTracer()
 
-		for i := range spans[0].Attributes() {
-			t.Log(spans[0].Attributes()[i].Key)
+		m := struct {
+			ValStrIgnored string `otel:"-"`
+		}{
+			ValStrIgnored: "a_string",
+		}
+
+		func() {
+			_, span := tracer.Start(
+				context.Background(),
+				testOperationName,
+				trace.WithAttributes(oteltag.SpanAttributes(m)...),
+			)
+			defer span.End()
+		}()
+
+		spans := spanRecorder.Ended()
+		if len(spans) != wantSpanCount {
+			t.Errorf("\ngot %d spans\nwant %d", len(spans), wantSpanCount)
+		}
+
+		attrCount := len(spans[0].Attributes())
+		if attrCount != expectedAttributeCount {
+			t.Errorf("\ngot %d attributes\nwant %d", attrCount, expectedAttributeCount)
 		}
 	})
 }