// Given a variable definition, and any value of input, return a value which
// adheres to the variable definition, or throw an error.
func getVariableValue(schema Schema, definitionAST *ast.VariableDefinition, input interface{}) (interface{}, error) {
ttype, err := typeFromAST(schema, definitionAST.Type)
if err != nil {
return nil, err
}
variable := definitionAST.Variable
if ttype == nil || !IsInputType(ttype) {
return "", gqlerrors.NewError(
fmt.Sprintf(`Variable "$%v" expected value of type `+
`"%v" which cannot be used as an input type.`, variable.Name.Value, printer.Print(definitionAST.Type)),
[]ast.Node{definitionAST},
"",
nil,
[]int{},
)
}
if isValidInputValue(input, ttype) {
if isNullish(input) {
defaultValue := definitionAST.DefaultValue
if defaultValue != nil {
variables := map[string]interface{}{}
val := valueFromAST(defaultValue, ttype, variables)
return val, nil
}
}
return coerceValue(ttype, input), nil
}
if isNullish(input) {
return "", gqlerrors.NewError(
fmt.Sprintf(`Variable "$%v" of required type `+
`"%v" was not provided.`, variable.Name.Value, printer.Print(definitionAST.Type)),
[]ast.Node{definitionAST},
"",
nil,
[]int{},
)
}
inputStr := ""
b, err := json.Marshal(input)
if err == nil {
inputStr = string(b)
}
return "", gqlerrors.NewError(
fmt.Sprintf(`Variable "$%v" expected value of type `+
`"%v" but got: %v.`, variable.Name.Value, printer.Print(definitionAST.Type), inputStr),
[]ast.Node{definitionAST},
"",
nil,
[]int{},
)
}
// Extracts the root type of the operation from the schema.
func getOperationRootType(schema Schema, operation ast.Definition) (*Object, error) {
if operation == nil {
return nil, errors.New("Can only execute queries and mutations")
}
switch operation.GetOperation() {
case ast.OperationTypeQuery:
return schema.QueryType(), nil
case ast.OperationTypeMutation:
mutationType := schema.MutationType()
if mutationType.PrivateName == "" {
return nil, gqlerrors.NewError(
"Schema is not configured for mutations",
[]ast.Node{operation},
"",
nil,
[]int{},
nil,
)
}
return mutationType, nil
case ast.OperationTypeSubscription:
subscriptionType := schema.SubscriptionType()
if subscriptionType.PrivateName == "" {
return nil, gqlerrors.NewError(
"Schema is not configured for subscriptions",
[]ast.Node{operation},
"",
nil,
[]int{},
nil,
)
}
return subscriptionType, nil
default:
return nil, gqlerrors.NewError(
"Can only execute queries, mutations and subscription",
[]ast.Node{operation},
"",
nil,
[]int{},
nil,
)
}
}
func NewLocatedError(err interface{}, nodes []ast.Node) *gqlerrors.Error {
message := "An unknown error occurred."
if err, ok := err.(error); ok {
message = err.Error()
}
if err, ok := err.(string); ok {
message = err
}
stack := message
return gqlerrors.NewError(
message,
nodes,
stack,
nil,
[]int{},
)
}