adding the glide Vendor Package Management support

vendor/github.com/docker/distribution/registry/client/errors.go

@@ -0,0 +1,103 @@
+package client
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+
+	"github.com/docker/distribution/registry/api/errcode"
+)
+
+// ErrNoErrorsInBody is returned when a HTTP response body parses to an empty
+// errcode.Errors slice.
+var ErrNoErrorsInBody = errors.New("no error details found in HTTP response body")
+
+// UnexpectedHTTPStatusError is returned when an unexpected HTTP status is
+// returned when making a registry api call.
+type UnexpectedHTTPStatusError struct {
+	Status string
+}
+
+func (e *UnexpectedHTTPStatusError) Error() string {
+	return fmt.Sprintf("received unexpected HTTP status: %s", e.Status)
+}
+
+// UnexpectedHTTPResponseError is returned when an expected HTTP status code
+// is returned, but the content was unexpected and failed to be parsed.
+type UnexpectedHTTPResponseError struct {
+	ParseErr   error
+	StatusCode int
+	Response   []byte
+}
+
+func (e *UnexpectedHTTPResponseError) Error() string {
+	return fmt.Sprintf("error parsing HTTP %d response body: %s: %q", e.StatusCode, e.ParseErr.Error(), string(e.Response))
+}
+
+func parseHTTPErrorResponse(statusCode int, r io.Reader) error {
+	var errors errcode.Errors
+	body, err := ioutil.ReadAll(r)
+	if err != nil {
+		return err
+	}
+
+	// For backward compatibility, handle irregularly formatted
+	// messages that contain a "details" field.
+	var detailsErr struct {
+		Details string `json:"details"`
+	}
+	err = json.Unmarshal(body, &detailsErr)
+	if err == nil && detailsErr.Details != "" {
+		if statusCode == http.StatusUnauthorized {
+			return errcode.ErrorCodeUnauthorized.WithMessage(detailsErr.Details)
+		}
+		return errcode.ErrorCodeUnknown.WithMessage(detailsErr.Details)
+	}
+
+	if err := json.Unmarshal(body, &errors); err != nil {
+		return &UnexpectedHTTPResponseError{
+			ParseErr:   err,
+			StatusCode: statusCode,
+			Response:   body,
+		}
+	}
+
+	if len(errors) == 0 {
+		// If there was no error specified in the body, return
+		// UnexpectedHTTPResponseError.
+		return &UnexpectedHTTPResponseError{
+			ParseErr:   ErrNoErrorsInBody,
+			StatusCode: statusCode,
+			Response:   body,
+		}
+	}
+
+	return errors
+}
+
+// HandleErrorResponse returns error parsed from HTTP response for an
+// unsuccessful HTTP response code (in the range 400 - 499 inclusive). An
+// UnexpectedHTTPStatusError returned for response code outside of expected
+// range.
+func HandleErrorResponse(resp *http.Response) error {
+	if resp.StatusCode == 401 {
+		err := parseHTTPErrorResponse(resp.StatusCode, resp.Body)
+		if uErr, ok := err.(*UnexpectedHTTPResponseError); ok {
+			return errcode.ErrorCodeUnauthorized.WithDetail(uErr.Response)
+		}
+		return err
+	}
+	if resp.StatusCode >= 400 && resp.StatusCode < 500 {
+		return parseHTTPErrorResponse(resp.StatusCode, resp.Body)
+	}
+	return &UnexpectedHTTPStatusError{Status: resp.Status}
+}
+
+// SuccessStatus returns true if the argument is a successful HTTP response
+// code (in the range 200 - 399 inclusive).
+func SuccessStatus(status int) bool {
+	return status >= 200 && status <= 399
+}