First version of the tracing library

[ric-plt/tracelibgo.git] / README.md

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+# Tracing helper library
+
+The library creates a configured tracer instance.
+
+ToDO: configuration...
+
+## Usage
+
+Create a tracer instance and set it as a global tracer:
+
+```go
+import (
+               "github.com/opentracing/opentracing-go"
+        "gerrit.o-ran-sc.org/ric-plt/tracelibgo/pkg/tracelibgo"
+        ...
+)
+
+tracer, closer := tracelibgo.CreateTracer("my-service-name")
+defer closer.Close()
+opentracing.SetGlobalTracer(tracer)
+```
+
+Serialize span context to a byte array that can be sent
+to another component via some messaging. For example, using
+the RMR library. The serialization uses JSON format.
+
+```go
+       carrier := make(map[string]string)
+       opentracing.GlobalTracer().Inject(
+                       span.Context(),
+                       opentracing.TextMap,
+                       opentracing.TextMapCarrier(carrier))
+       b, err := json.Marshal(carrier) // b is a []byte and contains serilized span context
+```
+
+Extract a span context from byte array and create a new child span from it.
+The serialized span context is got, for example, from the RMR library.
+
+```go
+       var carrier map[string]string
+       err = json.Unmarshal(data, &carrier) // data is []byte containing serialized span context
+       if err != nil {
+               ...
+       }
+       context, err := opentracing.GlobalTracer().Extract(opentracing.TextMap, opentracing.TextMapCarrier(carrier))
+       if err != nil {
+               ...
+       }
+       span := opentracing.GlobalTracer().StartSpan("go test span", opentracing.ChildOf(context))
+```
+
+## Unit testing
+
+ GO111MODULE=on go mod download
+ go test ./pkg/tracelibgo
+
+## License
+
+See [LICENSES.txt](LICENSES.txt) file.