added timeout error

pkg/http/api_errors.go

@@ -22,6 +22,14 @@ func (err *ErrResourceNotFoundError) Error() string {
 	return "resource not found"
 }
 
+// ErrTimeout will be sent if the request took too long
+type ErrTimeout string
+
+// Implement Error interface
+func (err ErrTimeout) Error() string {
+	return string(err)
+}
+
 // Variables
 var (
 	ErrSourceNotFound = &ErrResourceNotFoundError{}
@@ -50,6 +58,7 @@ const (
 	StatusError            = http.StatusInternalServerError
 	StatusResourceNotFound = http.StatusNotFound
 	StatusValidationError  = http.StatusBadRequest
+	TimeoutError           = http.StatusGatewayTimeout
 )
 
 // Handle an error and create a error API response
@@ -63,6 +72,10 @@ func apiErrorResponse(
 	status := StatusError
 
 	switch e := err.(type) {
+	case ErrTimeout:
+		tag = TagConnectionTimeout
+		code = CodeConnectionTimeout
+		status = TimeoutError
 	case *ErrResourceNotFoundError:
 		tag = TagResourceNotFound
 		code = CodeResourceNotFound

pkg/http/api_validators.go

@@ -48,7 +48,7 @@ func NewErrEmptyParam(key string) *ErrValidationFailed {
 
 var (
 	// ErrQueryTooShort will be returned when the query
-	// is less than 2 characters.
+	// is too short.
 	ErrQueryTooShort = &ErrValidationFailed{
 		"q", "the query is too short",
 	}
@@ -106,10 +106,10 @@ func validatePrefixQuery(value string) (string, error) {
 // Helper: Validate neighbors query. A valid query should have
 // at least 4 chars.
 func validateNeighborsQuery(value string) (string, error) {
-	if len(value) < 3 {
-		// Maybe make configurable,
-		// A length of 3 would be sufficient for "DFN" and
-		// other shorthands.
+	if len(value) < 4 {
+		// TODO: Maybe make configurable
+		// Three letters tend to result in queries with too
+		// many results, which then leads to gateway timeouts.
 		return "", ErrQueryTooShort
 	}
 	return value, nil