Add examples for an Primitive type array and Primitive type map.

As someone new to Avro it was not immediately apparent how to implement these use cases.

examples/arraySimpleField/arraySimpleField.go

@@ -0,0 +1,100 @@
+// Copyright 2015 LinkedIn Corp. Licensed under the Apache License,
+// Version 2.0 (the "License"); you may not use this file except in
+// compliance with the License.
 You may obtain a copy of the License
+// at http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// 
distributed under the License is distributed on an "AS IS" BASIS,
+// 
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+// implied.Copyright [201X] LinkedIn Corp. Licensed under the Apache
+// License, Version 2.0 (the "License"); you may not use this file
+// except in compliance with the License.
 You may obtain a copy of
+// the License at http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// 
distributed under the License is distributed on an "AS IS" BASIS,
+// 
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+// implied.
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+
+	"github.com/linkedin/goavro"
+)
+
+const schema = `{
+  "type": "record",
+  "name": "wordList",
+  "namespace": "com.example",
+  "doc:": "List of words",
+  "fields": [
+    {
+      "type": {
+        "items": "string",
+        "type": "array"
+      },
+      "name": "words"
+    }
+  ]
+}
+`
+
+var codec goavro.Codec
+
+func init() {
+	var err error
+	// If you want speed, create the codec one time for each
+	// schema and reuse it to create multiple Writer instances.
+	codec, err = goavro.NewCodec(schema)
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+func main() {
+	// Simple array's do not need to be enclosed in goavro.NewRecord
+	// but only passed in a slice of interface{}
+	innerRecords := []interface{}{
+		"Hello",
+		"World",
+	}
+
+	// Simply add the array directly to the record
+	record, err := goavro.NewRecord(goavro.RecordSchema(schema))
+	if err != nil {
+		log.Fatal(err)
+	}
+	record.Set("words", innerRecords)
+
+	// Encode the record into a bytes.Buffer
+	bb := new(bytes.Buffer)
+	if err = codec.Encode(bb, record); err != nil {
+		log.Fatal(err)
+	}
+
+	// Compare encoded bytes against the expected bytes.
+	actual := bb.Bytes()
+	expected := []byte(
+		"\x04" + // array of two elements
+			"\x0aHello" + // first element
+			"\x0aWorld\x00") // second element
+	if bytes.Compare(actual, expected) != 0 {
+		log.Printf("Actual: %#v; Expected: %#v", actual, expected)
+	}
+
+	// Let's decode the blob and print the output in JSON format
+	// using goavro.Record's String() method.
+	decoded, err := codec.Decode(bytes.NewReader(actual))
+	fmt.Println(decoded)
+	// we only need to perform type assertion if we want to access inside
+	result := decoded.(*goavro.Record)
+	fmt.Println("Record Name:", result.Name)
+	fmt.Println("Record Fields:")
+	for i, field := range result.Fields {
+		fmt.Println(" field", i, field.Name, ":", field.Datum)
+	}
+}

examples/mapSimpleField/mapSimpleField.go

@@ -0,0 +1,99 @@
+// Copyright 2015 LinkedIn Corp. Licensed under the Apache License,
+// Version 2.0 (the "License"); you may not use this file except in
+// compliance with the License.
 You may obtain a copy of the License
+// at http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// 
distributed under the License is distributed on an "AS IS" BASIS,
+// 
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+// implied.Copyright [201X] LinkedIn Corp. Licensed under the Apache
+// License, Version 2.0 (the "License"); you may not use this file
+// except in compliance with the License.
 You may obtain a copy of
+// the License at http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// 
distributed under the License is distributed on an "AS IS" BASIS,
+// 
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+// implied.
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+
+	"github.com/linkedin/goavro"
+)
+
+const schema = `{
+  "type": "record",
+  "name": "wordCount",
+  "namespace": "com.example",
+  "doc:": "Count of words",
+  "fields": [
+    {
+      "type": {
+        "values": "int",
+        "type": "map"
+      },
+      "name": "counts"
+    }
+  ]
+}
+`
+
+var codec goavro.Codec
+
+func init() {
+	var err error
+	// If you want speed, create the codec one time for each
+	// schema and reuse it to create multiple Writer instances.
+	codec, err = goavro.NewCodec(schema)
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+func main() {
+	// Map's do not need to be enclosed in goavro.NewRecord
+	// but only passed in as map[string]interface{}
+	// According Avro specification the key must be a string but
+	// the values can be any valid Avro type.
+	// Simple types do not need to be added as goavro.Record but
+	// Complex types do.
+	// Type Reference: https://avro.apache.org/docs/current/spec.html
+	innerRecords := map[string]interface{}{
+		"Hello": int32(3),
+		"World": int32(66),
+	}
+
+	// Simply add the map directly to the record
+	record, err := goavro.NewRecord(goavro.RecordSchema(schema))
+	if err != nil {
+		log.Fatal(err)
+	}
+	record.Set("counts", innerRecords)
+
+	// Encode the record into a bytes.Buffer
+	bb := new(bytes.Buffer)
+	if err = codec.Encode(bb, record); err != nil {
+		log.Fatal(err)
+	}
+
+	// We cannot compare encoded bytes against the expected bytes
+	// as we do in other examples due to Go's nondeterministic map ordering
+
+	// Let's decode the blob and print the output in JSON format
+	// using goavro.Record's String() method.
+	actual := bb.Bytes()
+	decoded, err := codec.Decode(bytes.NewReader(actual))
+	fmt.Println(decoded)
+	// we only need to perform type assertion if we want to access inside
+	result := decoded.(*goavro.Record)
+	fmt.Println("Record Name:", result.Name)
+	fmt.Println("Record Fields:")
+	for i, field := range result.Fields {
+		fmt.Println(" field", i, field.Name, ":", field.Datum)
+	}
+}