Move all backends into backend directory

backend/yandex/api/error.go

@@ -0,0 +1,84 @@
+package src
+
+//from yadisk
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+)
+
+// ErrorResponse represents erroneous API response.
+// Implements go's built in `error`.
+type ErrorResponse struct {
+	ErrorName   string `json:"error"`
+	Description string `json:"description"`
+	Message     string `json:"message"`
+
+	StatusCode int `json:""`
+}
+
+func (e *ErrorResponse) Error() string {
+	return fmt.Sprintf("[%d - %s] %s (%s)", e.StatusCode, e.ErrorName, e.Description, e.Message)
+}
+
+// ProccessErrorResponse tries to represent data passed as
+// an ErrorResponse object.
+func ProccessErrorResponse(data io.Reader) (*ErrorResponse, error) {
+	dec := json.NewDecoder(data)
+	var errorResponse ErrorResponse
+
+	if err := dec.Decode(&errorResponse); err == io.EOF {
+		// ok
+	} else if err != nil {
+		return nil, err
+	}
+
+	// TODO: check if there is any trash data after JSON and crash if there is.
+
+	return &errorResponse, nil
+}
+
+// CheckAPIError is a convenient function to turn erroneous
+// API response into go error.  It closes the Body on error.
+func CheckAPIError(resp *http.Response) (err error) {
+	if resp.StatusCode >= 200 && resp.StatusCode < 400 {
+		return nil
+	}
+
+	defer CheckClose(resp.Body, &err)
+
+	errorResponse, err := ProccessErrorResponse(resp.Body)
+	if err != nil {
+		return err
+	}
+	errorResponse.StatusCode = resp.StatusCode
+
+	return errorResponse
+}
+
+// ProccessErrorString tries to represent data passed as
+// an ErrorResponse object.
+func ProccessErrorString(data string) (*ErrorResponse, error) {
+	var errorResponse ErrorResponse
+	if err := json.Unmarshal([]byte(data), &errorResponse); err == nil {
+		// ok
+	} else if err != nil {
+		return nil, err
+	}
+
+	// TODO: check if there is any trash data after JSON and crash if there is.
+
+	return &errorResponse, nil
+}
+
+// ParseAPIError Parse json error response from API
+func (c *Client) ParseAPIError(jsonErr string) (string, error) { //ErrorName
+	errorResponse, err := ProccessErrorString(jsonErr)
+	if err != nil {
+		return err.Error(), err
+	}
+
+	return errorResponse.ErrorName, nil
+}