add cnf/json set() + tests pass

This commit is contained in:
xdrm-brackets 2018-11-07 15:51:54 +01:00
parent ad7c79d2f9
commit fa647530ea
2 changed files with 179 additions and 10 deletions

View File

@ -2,6 +2,7 @@ package cnf
import (
"encoding/json"
"fmt"
"io"
"strings"
)
@ -26,29 +27,100 @@ func (d *Json) Parse(_reader io.Reader) error {
}
// Get returns the value of a dot-separated path, and if it exists
func (d *Json) Get(_path string) (string, bool) {
// browse returns the target of a dot-separated path (as an interface{} chain where the last is the target if found)
func (d *Json) browse(_path string) ([]interface{}, bool) {
// 1. extract path
path := strings.Split(_path, ".")
// 2. Iterate over path / nested fields
// 2. init output chain
current := d.data
chain := make([]interface{}, 0, len(path)+1)
chain = append(chain, current)
// 3. iterate over path / nested fields
for _, field := range path {
fmap, ok := current.(map[string]interface{})
if !ok { // incomplete path
return "", false
return chain, false
}
child, ok := fmap[field]
if !ok { // incomplete path
return "", false
return chain, false
}
current = child
chain = append(chain, current)
}
// 3. Only return if string value
value, ok := current.(string)
return value, ok
return chain, true
}
// Get returns the value of a dot-separated path, and if it exists
func (d *Json) Get(_path string) (string, bool) {
// 1. browse path
chain, found := d.browse(_path)
if !found {
return "", false
}
// 2. return if string value
value, ok := chain[len(chain)-1].(string)
return value, ok
}
// Set the value of a dot-separated path, and creates it if not found
func (d *Json) Set(_path, _value string) bool {
// 1. browse path + create it if does not exist
path := strings.Split(_path, ".")
chain, found := d.browse(_path)
// 2. if found -> set value
if found {
mapWrapper, ok := chain[len(chain)-2].(map[string]interface{})
if !ok { // impossible
return false
}
key := path[len(path)-1]
mapWrapper[key] = _value
return true
}
// 3. create path until the end to set value
root := make(map[string]interface{})
current := root
// create children until second to last
fmt.Printf("%d / %d\n", len(chain)-1, len(path))
for i, l := len(chain)-1, len(path)-1; i < l; i++ {
child := make(map[string]interface{})
fmt.Printf("add '%s'\n", path[i])
current[path[i]] = child
current = child
}
// set value
current[path[len(path)-1]] = _value
// replace whole object if empty
if len(chain) < 2 {
d.data = root
return true
}
// update last found object to add the value
wrapper, ok := chain[len(chain)-2].(map[string]interface{})
if !ok { // impossible
return false
}
key := path[len(chain)-2]
wrapper[key] = root
return true
}

View File

@ -5,7 +5,7 @@ import (
"testing"
)
func TestSimpleJson(t *testing.T) {
func TestGet(t *testing.T) {
tests := []struct {
raw string
@ -45,7 +45,7 @@ func TestSimpleJson(t *testing.T) {
}
func TestNotString(t *testing.T) {
func TestGetNotString(t *testing.T) {
tests := []struct {
raw string
@ -79,3 +79,100 @@ func TestNotString(t *testing.T) {
}
}
func TestSetPathExistsAndIsString(t *testing.T) {
tests := []struct {
raw string
key string
value string
}{
{`{ "key": "value" }`, "key", "newvalue"},
{`{ "ignore": "xxx", "key": "value" }`, "key", "newvalue"},
{`{ "parent": { "child": "value" } }`, "parent.child", "newvalue"},
{`{ "ignore": "xxx", "parent": { "child": "value" } }`, "parent.child", "newvalue"},
}
for _, test := range tests {
parser := new(Json)
reader := bytes.NewBufferString(test.raw)
// try to extract value
err := parser.Parse(reader)
if err != nil {
t.Errorf("parse error: %s", err)
continue
}
// update value
if !parser.Set(test.key, test.value) {
t.Errorf("cannot set '%s' to '%s'", test.key, test.value)
continue
}
// check new value
value, found := parser.Get(test.key)
if !found {
t.Errorf("expected a result, got none")
continue
}
// check value
if value != test.value {
t.Errorf("expected '%s' got '%s'", test.value, value)
}
}
}
func TestSetCreatePath(t *testing.T) {
tests := []struct {
raw string
key string
value string
}{
{`{ }`, "key", "newvalue"},
{`{ }`, "parent.child", "newvalue"},
{`{ }`, "parent.child.subchild", "newvalue"},
{`{ "ignore": "xxx" }`, "key", "newvalue"},
{`{ "parent": { } }`, "parent.child", "newvalue"},
{`{ "ignore": "xxx", "parent": { } }`, "parent.child", "newvalue"},
}
for i, test := range tests {
parser := new(Json)
reader := bytes.NewBufferString(test.raw)
// try to extract value
err := parser.Parse(reader)
if err != nil {
t.Errorf("[%d] parse error: %s", i, err)
continue
}
// update value
if !parser.Set(test.key, test.value) {
t.Errorf("[%d] cannot set '%s' to '%s'", i, test.key, test.value)
continue
}
// check new value
value, found := parser.Get(test.key)
if !found {
t.Errorf("[%d] expected a result, got none", i)
continue
}
// check value
if value != test.value {
t.Errorf("[%d] expected '%s' got '%s'", i, test.value, value)
}
}
}