Merge pull request #4 from SoulKa/feature/add-examples

Move examples to root

examples/example_test.go → example_test.go

@@ -1,15 +1,15 @@
-package examples
+package golymorph_test
 
 import (
 	"encoding/json"
 	"fmt"
 	"github.com/SoulKa/golymorph"
 	"github.com/mitchellh/mapstructure"
 	"reflect"
-	"testing"
 )
 
-func TestBasicPolymorphismFromJson(t *testing.T) {
+// ExampleUnmarshalJSON demonstrates how to use the polymorpher to unmarshal a JSON into a struct with a polymorphic field.
+func ExampleUnmarshalJSON() {
 
 	// get a JSON that contains a payload with a type field that determines the type of the payload
 	alertEventJson := `{ "timestamp": "2023-11-27T22:14:09+00:00", "payload": { "type": "alert", "message": "something is broken!" } }`
@@ -55,9 +55,15 @@ func TestBasicPolymorphismFromJson(t *testing.T) {
 	// continue to work with the event
 	fmt.Printf("event: %+v\n", event)
 	fmt.Printf("event payload: %T %+v\n", event.Payload, event.Payload.(AlertPayload))
+
+	// Output:
+	// event: {Timestamp:2023-11-27T22:14:09+00:00 Payload:{Type:alert Message:something is broken!}}
+	// event payload: golymorph_test.AlertPayload {Type:alert Message:something is broken!}
 }
 
-func TestBasicPolymorphismWithManualParsing(t *testing.T) {
+// ExampleTypeMapPolymorphism_AssignTargetType demonstrates how to use the polymorpher to assign the
+// type of a polymorphic field in an existing struct instance.
+func ExampleTypeMapPolymorphism_AssignTargetType() {
 
 	// get a JSON that contains a payload with a type field that determines the type of the payload
 	alertEventJson := `{ "timestamp": "2023-11-27T22:14:09+00:00", "payload": { "type": "alert", "message": "something is broken!" } }`
@@ -85,7 +91,7 @@ func TestBasicPolymorphismWithManualParsing(t *testing.T) {
 	// parse the JSON into a map
 	var jsonMap map[string]any
 	if err := json.Unmarshal([]byte(alertEventJson), &jsonMap); err != nil {
-		t.Fatalf("error unmarshalling JSON: %s", err)
+		panic(fmt.Sprintf("error unmarshalling JSON: %s", err))
 	}
 
 	// create a polymorpher that assigns the type of the payload based on the type field
@@ -95,21 +101,25 @@ func TestBasicPolymorphismWithManualParsing(t *testing.T) {
 		WithDiscriminatorAt("type").
 		Build()
 	if err != nil {
-		t.Fatalf("error building polymorpher: %s", err)
+		panic(fmt.Sprintf("error building polymorpher: %s", err))
 	}
 
 	// create a new event
 	var event Event
 	if err := polymorpher.AssignTargetType(&jsonMap, &event); err != nil {
-		t.Fatalf("error assigning target type: %s", err)
+		panic(fmt.Sprintf("error assigning target type: %s", err))
 	}
 
 	// use mapstructure to unmarshal the payload into the event
 	if err := mapstructure.Decode(jsonMap, &event); err != nil {
-		t.Fatalf("error decoding JSON map: %s", err)
+		panic(fmt.Sprintf("error decoding JSON map: %s", err))
 	}
 
 	// continue to work with the event
 	fmt.Printf("event: %+v\n", event)
 	fmt.Printf("event payload: %T %+v\n", event.Payload, event.Payload.(AlertPayload))
+
+	// Output:
+	// event: {Timestamp:2023-11-27T22:14:09+00:00 Payload:{Type:alert Message:something is broken!}}
+	// event payload: golymorph_test.AlertPayload {Type:alert Message:something is broken!}
 }