Merge pull request #11 from tuan78/chore/handle-newline-delimited-jso…

…narray

chore: handle newline delimited JSON array

.github/workflows/codecov.yml

@@ -3,21 +3,21 @@ name: Test and coverage
 on:
   push:
     branches:
-      - 'main'
+      - "main"
   pull_request:
 
 jobs:
   build:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout current branch
-        uses: actions/checkout@v2
+        uses: actions/checkout@master
 
       - name: Setup Golang
         uses: actions/setup-go@v2
         with:
-          go-version: '1.18'
-      
+          go-version: "1.18"
+
       - name: Load cached dependencies
         uses: actions/cache@v3
         with:
@@ -35,7 +35,7 @@ jobs:
           (cd benchmarks && go mod download)
 
       - name: Run coverage
-        run: | 
+        run: |
           make cover
           (cd cmd && make cover)
 
@@ -57,4 +57,4 @@ jobs:
           flags: cmd
           name: cmd
           fail_ci_if_error: true
-          verbose: true
+          verbose: true

json_reader.go

@@ -3,15 +3,17 @@ package jsonconv
 import (
 	"encoding/json"
 	"io"
+	"reflect"
+	"strings"
 )
 
 // A JsonReader reads and decodes JSON values from an input stream.
 type JsonReader struct {
-	reader io.Reader
+	reader io.ReadSeeker
 }
 
 // NewJsonReader returns a new JsonReader that reads from r.
-func NewJsonReader(r io.Reader) *JsonReader {
+func NewJsonReader(r io.ReadSeeker) *JsonReader {
 	return &JsonReader{
 		reader: r,
 	}
@@ -21,11 +23,40 @@ func NewJsonReader(r io.Reader) *JsonReader {
 // input and stores it in the value pointed to by v.
 func (r *JsonReader) Read(v interface{}) error {
 	decoder := json.NewDecoder(r.reader)
-	for decoder.More() {
-		err := decoder.Decode(v)
-		if err != nil {
+	err := decoder.Decode(v)
+	if err != nil {
+		if !strings.Contains(err.Error(), "cannot unmarshal object into Go value of type") {
 			return err
 		}
+
+		// The JSON data is a valid JSON array. However, we will try to decode it line by line.
+		// Reset reader and decoder.
+		r.reader.Seek(0, io.SeekStart)
+		decoder = json.NewDecoder(r.reader)
+
+		// Check if v is a pointer to a slice or an array. If not, return an error.
+		refval := reflect.ValueOf(v)
+		if refval.Kind() == reflect.Pointer {
+			refval = refval.Elem()
+		}
+		if refval.Kind() != reflect.Slice && refval.Kind() != reflect.Array {
+			return err
+		}
+
+		// Decode JSON array into v.
+		for {
+			obj := reflect.New(refval.Type().Elem())
+			objInterface := obj.Interface()
+			err := decoder.Decode(objInterface)
+			if err != nil {
+				if err == io.EOF {
+					reflect.ValueOf(v).Elem().Set(refval)
+					return nil
+				}
+				return err
+			}
+			refval.Set(reflect.Append(refval, reflect.ValueOf(objInterface).Elem()))
+		}
 	}
 	return nil
 }

json_reader_test.go

@@ -80,7 +80,46 @@ func TestJsonReader_JsonArray(t *testing.T) {
 	}
 
 	// Check
-	if len(arr) == 0 {
+	if len(arr) != 3 {
+		t.Fatalf("failed to read json array")
+	}
+	if arr[0]["id"] != "ce06f5b1-5721-42c0-91e1-9f72a09c250a" ||
+		arr[0]["user"] != "Tuấn" ||
+		arr[0]["score"] != "1.5" ||
+		arr[0]["is active"] != "true" {
+		t.Fatalf("failed to read json array")
+	}
+	if arr[1]["id"] != "b042ab5c-ca73-4460-b739-96410ea9d3a6" ||
+		arr[1]["user"] != "Jon Doe" ||
+		arr[1]["score"] != "-100" ||
+		arr[1]["is active"] != "false" {
+		t.Fatalf("failed to read json array")
+	}
+	if arr[2]["id"] != "4e01b638-44e5-4079-8043-baabbff21cc8" ||
+		arr[2]["user"] != "高橋" ||
+		arr[2]["score"] != "100000000000000000000000" ||
+		arr[2]["is active"] != "true" {
+		t.Fatalf("failed to read json array")
+	}
+}
+
+func TestJsonReader_JsonArray_NewlineDelimited(t *testing.T) {
+	// Prepare
+	raw := `
+		{"id": "ce06f5b1-5721-42c0-91e1-9f72a09c250a","user": "Tuấn","score": "1.5","is active": "true"}
+		{"id": "b042ab5c-ca73-4460-b739-96410ea9d3a6","user": "Jon Doe","score": "-100","is active": "false"}
+		{"id": "4e01b638-44e5-4079-8043-baabbff21cc8","user": "高橋","score": "100000000000000000000000","is active": "true"}`
+	arr := make(JsonArray, 0)
+	re := NewJsonReader(strings.NewReader(raw))
+
+	// Process
+	err := re.Read(&arr)
+	if err != nil {
+		t.Fatalf("failed to read file %v", err)
+	}
+
+	// Check
+	if len(arr) != 3 {
 		t.Fatalf("failed to read json array")
 	}
 	if arr[0]["id"] != "ce06f5b1-5721-42c0-91e1-9f72a09c250a" ||