Initial QSfera import

Server/vendor/github.com/crewjam/httperr/value.go

@@ -0,0 +1,67 @@
+// Package httperr implements an error object that speaks HTTP.
+package httperr
+
+import (
+	"fmt"
+	"net/http"
+)
+
+// Value is an Error that returns that status and code
+// provided, and reveals the underlying wrapper error to
+// the caller. The text of the error is rendered to the
+// client in the body of the response, as well as in
+// the X-Error header.
+type Value struct {
+	Err        error  // the underlying error
+	StatusCode int    // the HTTP status code. If not supplied, http.StatusInternalServerError is used.
+	Status     string // the HTTP status text. If not supplied, http.StatusText(http.StatusCode) is used.
+	Public     bool
+	Header     http.Header // extra headers to add to the response (optional)
+}
+
+// StatusCodeAndText returns the status code and text of the error
+func (e Value) StatusCodeAndText() (int, string) {
+	if e.StatusCode == 0 {
+		e.StatusCode = http.StatusInternalServerError
+	}
+
+	if e.Status == "" {
+		if e.Err != nil && e.Public {
+			e.Status = e.Err.Error()
+		} else {
+			e.Status = http.StatusText(e.StatusCode)
+		}
+	}
+
+	return e.StatusCode, e.Status
+}
+
+func (e Value) Error() string {
+	statusCode, statusText := StatusCodeAndText(e)
+	if e.Public {
+		return fmt.Sprintf("%d %s", statusCode, statusText)
+	}
+	return fmt.Sprintf("%d %s: %s", statusCode, statusText, e.Err.Error())
+}
+
+// WriteError writes an error response to w using the specified status code.
+func (e Value) WriteError(w http.ResponseWriter, r *http.Request) {
+	for key, values := range e.Header {
+		w.Header().Del(key) // overwrite headers already in the response with the ones specified
+		for _, value := range values {
+			w.Header().Add(key, value)
+		}
+	}
+
+	code, message := e.StatusCodeAndText()
+	http.Error(w, message, code)
+}
+
+// Unwrap unwraps the Value error and returns the underlying error`
+func (e Value) Unwrap() error {
+	return e.Err
+}
+
+var _ error = Value{}
+var _ Writer = Value{}
+var _ statusCodeAndTexter = Value{}