feat(goavro) Adding method to return typename associated with Codec

**Overview:**
In order to identify the kafka topic name from a stream of topics, we
need to identify the underlying type associated with the provided Codec
data
The `Codec.typeName` field already contains this information but is
currently package private and cannot be used outside of the package

This PR adds the `TypeName` method to `Codec` to expose the underlying
type name outside the goavro package scope
This also adds the `ShortName` method to `Name` to expose the short
name (i.e. record name excluding classpath) as a public method

codec.go

@@ -604,6 +604,12 @@ func (c *Codec) SchemaCRC64Avro() int64 {
 	return int64(c.Rabin)
 }
 
+// TypeName returns the name of the type described by the
+// schema used to create the Codec.
+func (c *Codec) TypeName() name {
+	return *c.typeName
+}
+
 // convert a schema data structure to a codec, prefixing with specified
 // namespace
 func buildCodec(st map[string]*Codec, enclosingNamespace string, schema interface{}, cb *codecBuilder) (*Codec, error) {

codec_test.go

@@ -145,6 +145,89 @@ func TestCodecRabin(t *testing.T) {
 	}
 }
 
+func TestTypeName(t* testing.T) {
+	cases := []struct {
+		Schema string
+		expectedFullName string
+		expectedNamespace string
+	}{
+		{
+			Schema: `"null"`,
+			expectedFullName: "null",
+			expectedNamespace: "",
+		},
+		{
+			Schema: `"boolean"`,
+			expectedFullName: "boolean",
+			expectedNamespace: "",
+		},
+		{
+			Schema: `"int"`,
+			expectedFullName: "int",
+			expectedNamespace: "",
+		},
+		{
+			Schema: `"long"`,
+			expectedFullName: "long",
+			expectedNamespace: "",
+		},
+		{
+			Schema: `"float"`,
+			expectedFullName: "float",
+			expectedNamespace: "",
+		},
+		{
+			Schema: `[ "int"  ]`,
+			expectedFullName: "union",
+			expectedNamespace: "",
+		},
+		{
+			Schema: `[ "int" , {"type":"boolean"} ]`,
+			expectedFullName: "union",
+			expectedNamespace: "",
+		},
+		{
+			Schema: `{"fields":[], "type":"record", "name":"foo"}`,
+			expectedFullName: "foo",
+			expectedNamespace: "",
+		},
+		{
+			Schema: `{"type":"enum", "name":"foo", "symbols":["A1"]}`,
+			expectedFullName: "foo",
+			expectedNamespace: "",
+		},
+		{
+			Schema: `{"name":"foo","type":"fixed","size":15}`,
+			expectedFullName: "foo",
+			expectedNamespace: "",
+		},
+		{
+			Schema: `{"fields":[], "type":"record", "name":"foo", "namespace":"x.y"}`,
+			expectedFullName: "foo",
+			expectedNamespace: "x.y",
+		},
+		{
+			Schema: `{"namespace":"x.y.z", "type":"enum", "name":"foo", "doc":"foo bar", "symbols":["A1", "A2"]}`,
+			expectedFullName: "foo",
+			expectedNamespace: "x.y.z",
+		},
+	}
+
+	for _, c := range cases {
+		codec, err := NewCodec(c.Schema)
+		if err != nil {
+			t.Fatalf("CASE: %s; cannot create codec: %s", c.Schema, err)
+		}
+		typeName := codec.TypeName()
+		expected, _ := newName(c.expectedFullName, c.expectedNamespace, "")
+		if typeName != *expected {
+			t.Errorf("CASE: %s; GOT: %s; WANT: %s", c.Schema, codec.TypeName(), *expected)
+		}
+	}
+}
+
+
+
 func TestSingleObjectEncoding(t *testing.T) {
 	t.Run("int", func(*testing.T) {
 		schema := `"int"`

name.go

@@ -141,3 +141,9 @@ func (n *name) short() string {
 	}
 	return n.fullName
 }
+
+// Shortname returns the name without the prefixed namespace.
+// This uses the short method underneath but is visible outside the package.
+func (n *name) ShortName() string {
+	return n.short()
+}

name_test.go

@@ -12,6 +12,7 @@ package goavro
 // NOTE: part of goavro package because it tests private functionality
 
 import (
+	"fmt"
 	"testing"
 )
 
@@ -98,3 +99,27 @@ func TestNewNameFromSchemaMap(t *testing.T) {
 		t.Errorf("GOT: %q; WANT: %q", got, want)
 	}
 }
+
+
+func TestShortName(t *testing.T) {
+	cases := []struct {
+		name     string
+		namespace string
+		want     string
+	}{
+		{"bar", "", "bar"},
+		{"foo", "org.bar", "foo"},
+		{"bar.foo", "org", "foo"},
+	}
+
+	for _, c := range cases {
+		n, err := newName(c.name, c.namespace, nullNamespace)
+		if err != nil {
+			t.Fatal(err)
+		}
+		fmt.Printf("n: %#v fullName: %v shortName: %v\n", n, n.String(), n.ShortName())
+		if actual, expected := n.ShortName(), c.want; actual != expected {
+			t.Errorf("GOT: %#v; WANT: %#v", actual, expected)
+		}
+	}
+}