func TestJsonFileRead(t *testing.T) {
wd, err := os.Getwd()
if err != nil {
t.Fatal(err)
}
filename := filepath.Join(wd, test_jsonfile)
// Read non-existent file
err = os.Remove(filename)
if err != nil && !os.IsNotExist(err) {
t.Fatal(err)
}
var foo fooStruct = fooStruct{60}
err = util.ReadJsonFromFile(filename, &foo)
if !os.IsNotExist(err) {
t.Fatal(err)
}
if foo.BarBaz != 60 {
t.Fatal(foo)
}
// Read bad file
var data []byte = []byte("BAD-JSON")
err = ioutil.WriteFile(filename, data, 0666)
if err != nil {
t.Fatal(err)
}
err = util.ReadJsonFromFile(filename, &foo)
if err.Error() != "invalid character 'B' looking for beginning of value" {
t.Fatal(err)
}
if foo.BarBaz != 60 {
t.Fatal(foo)
}
// Read good file
data = []byte("{\"barBaz\": 201}")
err = ioutil.WriteFile(filename, data, 0666)
if err != nil {
t.Fatal(err)
}
err = util.ReadJsonFromFile(filename, &foo)
if err != nil {
t.Fatal(err)
}
if foo.BarBaz != 201 {
t.Fatal(foo)
}
}
// Json file implementation of RaftPersistentState.
//
// The returned instance is safe for access from multiple goroutines.
//
// The file access is NOT concurrency safe (from this or from another process).
//
// Writes to "filename" and also "filename.bak" using SafeWriteJsonToFile().
func NewJsonFileRaftPersistentState(filename string) (RaftPersistentState, error) {
jfrps := &JsonFileRaftPersistentState{
&sync.Mutex{}, filename, rps{0, ""},
}
err := util.ReadJsonFromFile(filename, &jfrps.rps)
if err != nil {
if os.IsNotExist(err) {
jfrps.rps.CurrentTerm = 0
jfrps.rps.VotedFor = ""
} else {
return nil, err
}
}
return jfrps, nil
}