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package jsonutil
import (
"encoding/json"
"os"
"path/filepath"
"testing"
"github.com/ethereum-optimism/optimism/op-service/ioutil"
"github.com/stretchr/testify/require"
)
func TestRoundTripJSON(t *testing.T) {
dir := t.TempDir()
file := filepath.Join(dir, "test.json")
data := &jsonTestData{A: "yay", B: 3}
err := WriteJSON(data, ioutil.ToAtomicFile(file, 0o755))
require.NoError(t, err)
// Confirm the file is uncompressed
fileContent, err := os.ReadFile(file)
require.NoError(t, err)
err = json.Unmarshal(fileContent, &jsonTestData{})
require.NoError(t, err)
var result *jsonTestData
result, err = LoadJSON[jsonTestData](file)
require.NoError(t, err)
require.EqualValues(t, data, result)
}
func TestRoundTripJSONWithGzip(t *testing.T) {
dir := t.TempDir()
file := filepath.Join(dir, "test.json.gz")
data := &jsonTestData{A: "yay", B: 3}
err := WriteJSON(data, ioutil.ToAtomicFile(file, 0o755))
require.NoError(t, err)
// Confirm the file isn't raw JSON
fileContent, err := os.ReadFile(file)
require.NoError(t, err)
err = json.Unmarshal(fileContent, &jsonTestData{})
require.Error(t, err, "should not be able to decode without decompressing")
var result *jsonTestData
result, err = LoadJSON[jsonTestData](file)
require.NoError(t, err)
require.EqualValues(t, data, result)
}
func TestLoadJSONWithExtraDataAppended(t *testing.T) {
data := &jsonTestData{A: "yay", B: 3}
cases := []struct {
name string
extraData func() ([]byte, error)
}{
{
name: "duplicate json object",
extraData: func() ([]byte, error) {
return json.Marshal(data)
},
},
{
name: "duplicate comma-separated json object",
extraData: func() ([]byte, error) {
data, err := json.Marshal(data)
if err != nil {
return nil, err
}
return append([]byte(","), data...), nil
},
},
{
name: "additional characters",
extraData: func() ([]byte, error) {
return []byte("some text"), nil
},
},
}
for _, tc := range cases {
t.Run(tc.name, func(t *testing.T) {
dir := t.TempDir()
file := filepath.Join(dir, "test.json")
extraData, err := tc.extraData()
require.NoError(t, err)
// Write primary json payload + extra data to the file
err = WriteJSON(data, ioutil.ToAtomicFile(file, 0o755))
require.NoError(t, err)
err = appendDataToFile(file, extraData)
require.NoError(t, err)
var result *jsonTestData
result, err = LoadJSON[jsonTestData](file)
require.ErrorContains(t, err, "unexpected trailing data")
require.Nil(t, result)
})
}
}
func TestLoadJSONWithTrailingWhitespace(t *testing.T) {
cases := []struct {
name string
extraData []byte
}{
{
name: "space",
extraData: []byte(" "),
},
{
name: "tab",
extraData: []byte("\t"),
},
{
name: "new line",
extraData: []byte("\n"),
},
{
name: "multiple chars",
extraData: []byte(" \t\n"),
},
}
for _, tc := range cases {
t.Run(tc.name, func(t *testing.T) {
dir := t.TempDir()
file := filepath.Join(dir, "test.json")
data := &jsonTestData{A: "yay", B: 3}
// Write primary json payload + extra data to the file
err := WriteJSON(data, ioutil.ToAtomicFile(file, 0o755))
require.NoError(t, err)
err = appendDataToFile(file, tc.extraData)
require.NoError(t, err)
var result *jsonTestData
result, err = LoadJSON[jsonTestData](file)
require.NoError(t, err)
require.EqualValues(t, data, result)
})
}
}
type jsonTestData struct {
A string `json:"a"`
B int `json:"b"`
}
func appendDataToFile(outputPath string, data []byte) error {
file, err := os.OpenFile(outputPath, os.O_APPEND|os.O_WRONLY, 0644)
if err != nil {
return err
}
defer file.Close()
_, err = file.Write(data)
return err
}