bundle qson lib in util (#1561)

* copy qson from https://github.com/joncalhoun/qson
  as author not want to maintain repo
* latest code contains our fix to proper decode strings
  with escaped & symbol
* replace package in api/handler/rpc

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

util/qson/qson_test.go

@@ -0,0 +1,170 @@
+package qson
+
+import (
+	"fmt"
+	"testing"
+)
+
+func ExampleUnmarshal() {
+	type Ex struct {
+		A string `json:"a"`
+		B struct {
+			C int `json:"c"`
+		} `json:"b"`
+	}
+	var ex Ex
+	if err := Unmarshal(&ex, "a=xyz&b[c]=456"); err != nil {
+		panic(err)
+	}
+	fmt.Printf("%+v\n", ex)
+	// Output: {A:xyz B:{C:456}}
+}
+
+type unmarshalT struct {
+	A string     `json:"a"`
+	B unmarshalB `json:"b"`
+}
+type unmarshalB struct {
+	C int    `json:"c"`
+	D string `json:"D"`
+}
+
+func TestUnmarshal(t *testing.T) {
+	query := "a=xyz&b[c]=456"
+	expected := unmarshalT{
+		A: "xyz",
+		B: unmarshalB{
+			C: 456,
+		},
+	}
+	var actual unmarshalT
+	err := Unmarshal(&actual, query)
+	if err != nil {
+		t.Error(err)
+	}
+	if expected != actual {
+		t.Errorf("Expected: %+v Actual: %+v", expected, actual)
+	}
+}
+
+func ExampleToJSON() {
+	b, err := ToJSON("a=xyz&b[c]=456")
+	if err != nil {
+		panic(err)
+	}
+	fmt.Printf(string(b))
+	// Output: {"a":"xyz","b":{"c":456}}
+}
+
+func TestToJSONNested(t *testing.T) {
+	query := "bar%5Bone%5D%5Btwo%5D=2&bar[one][red]=112"
+	expected := `{"bar":{"one":{"red":112,"two":2}}}`
+	actual, err := ToJSON(query)
+	if err != nil {
+		t.Error(err)
+	}
+	actualStr := string(actual)
+	if actualStr != expected {
+		t.Errorf("Expected: %s Actual: %s", expected, actualStr)
+	}
+}
+
+func TestToJSONPlain(t *testing.T) {
+	query := "cat=1&dog=2"
+	expected := `{"cat":1,"dog":2}`
+	actual, err := ToJSON(query)
+	if err != nil {
+		t.Error(err)
+	}
+	actualStr := string(actual)
+	if actualStr != expected {
+		t.Errorf("Expected: %s Actual: %s", expected, actualStr)
+	}
+}
+
+func TestToJSONSlice(t *testing.T) {
+	query := "cat[]=1&cat[]=34"
+	expected := `{"cat":[1,34]}`
+	actual, err := ToJSON(query)
+	if err != nil {
+		t.Error(err)
+	}
+	actualStr := string(actual)
+	if actualStr != expected {
+		t.Errorf("Expected: %s Actual: %s", expected, actualStr)
+	}
+}
+
+func TestToJSONBig(t *testing.T) {
+	query := "distinct_id=763_1495187301909_3495&timestamp=1495187523&event=product_add_cart&params%5BproductRefId%5D=8284563078&params%5Bapps%5D%5B%5D=precommend&params%5Bapps%5D%5B%5D=bsales&params%5Bsource%5D=item&params%5Boptions%5D%5Bsegment%5D=cart_recommendation&params%5Boptions%5D%5Btype%5D=up_sell&params%5BtimeExpire%5D=1495187599642&params%5Brecommend_system_product_source%5D=item&params%5Bproduct_id%5D=8284563078&params%5Bvariant_id%5D=27661944134&params%5Bsku%5D=00483332%20(black)&params%5Bsources%5D%5B%5D=product_recommendation&params%5Bcart_token%5D=dc2c336a009edf2762128e65806dfb1d&params%5Bquantity%5D=1&params%5Bnew_popup_upsell_mobile%5D=false&params%5BclientDevice%5D=desktop&params%5BclientIsMobile%5D=false&params%5BclientIsSmallScreen%5D=false&params%5Bnew_popup_crossell_mobile%5D=false&api_key=14c5b7dacea9157029265b174491d340"
+	expected := `{"api_key":"14c5b7dacea9157029265b174491d340","distinct_id":"763_1495187301909_3495","event":"product_add_cart","params":{"apps":["precommend","bsales"],"cart_token":"dc2c336a009edf2762128e65806dfb1d","clientDevice":"desktop","clientIsMobile":false,"clientIsSmallScreen":false,"new_popup_crossell_mobile":false,"new_popup_upsell_mobile":false,"options":{"segment":"cart_recommendation","type":"up_sell"},"productRefId":8284563078,"product_id":8284563078,"quantity":1,"recommend_system_product_source":"item","sku":"00483332 (black)","source":"item","sources":["product_recommendation"],"timeExpire":1495187599642,"variant_id":27661944134},"timestamp":1495187523}`
+	actual, err := ToJSON(query)
+	if err != nil {
+		t.Error(err)
+	}
+	actualStr := string(actual)
+	if actualStr != expected {
+		t.Errorf("Expected: %s Actual: %s", expected, actualStr)
+	}
+}
+
+func TestToJSONDuplicateKey(t *testing.T) {
+	query := "cat=1&cat=2"
+	expected := `{"cat":2}`
+	actual, err := ToJSON(query)
+	if err != nil {
+		t.Error(err)
+	}
+	actualStr := string(actual)
+	if actualStr != expected {
+		t.Errorf("Expected: %s Actual: %s", expected, actualStr)
+	}
+}
+
+func TestSplitKeyAndValue(t *testing.T) {
+	param := "a[dog][=cat]=123"
+	eKey, eValue := "a[dog][=cat]", "123"
+	aKey, aValue, err := splitKeyAndValue(param)
+	if err != nil {
+		t.Error(err)
+	}
+	if eKey != aKey {
+		t.Errorf("Keys do not match. Expected: %s Actual: %s", eKey, aKey)
+	}
+	if eValue != aValue {
+		t.Errorf("Values do not match. Expected: %s Actual: %s", eValue, aValue)
+	}
+}
+
+func TestEncodedAmpersand(t *testing.T) {
+	query := "a=xyz&b[d]=ben%26jerry"
+	expected := unmarshalT{
+		A: "xyz",
+		B: unmarshalB{
+			D: "ben&jerry",
+		},
+	}
+	var actual unmarshalT
+	err := Unmarshal(&actual, query)
+	if err != nil {
+		t.Error(err)
+	}
+	if expected != actual {
+		t.Errorf("Expected: %+v Actual: %+v", expected, actual)
+	}
+}
+
+func TestEncodedAmpersand2(t *testing.T) {
+	query := "filter=parent%3Dflow12345%26request%3Dreq12345&meta.limit=20&meta.offset=0"
+	expected := map[string]interface{}{"filter": "parent=flow12345&request=req12345", "meta.limit": float64(20), "meta.offset": float64(0)}
+	actual := make(map[string]interface{})
+	err := Unmarshal(&actual, query)
+	if err != nil {
+		t.Error(err)
+	}
+	for k, v := range actual {
+		if nv, ok := expected[k]; !ok || nv != v {
+			t.Errorf("Expected: %+v Actual: %+v", expected, actual)
+		}
+	}
+}