graphql
Version:
A Query Language and Runtime which can target any service.
58 lines (52 loc) • 1.67 kB
Flow
/**
* Copyright (c) 2015-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @flow strict
*/
import type { ValidationContext } from '../ValidationContext';
import { GraphQLError } from '../../error/GraphQLError';
import type { ASTVisitor } from '../../language/visitor';
export function undefinedVarMessage(varName: string, opName: ?string): string {
return opName
? `Variable "$${varName}" is not defined by operation "${opName}".`
: `Variable "$${varName}" is not defined.`;
}
/**
* No undefined variables
*
* A GraphQL operation is only valid if all variables encountered, both directly
* and via fragment spreads, are defined by that operation.
*/
export function NoUndefinedVariables(context: ValidationContext): ASTVisitor {
let variableNameDefined = Object.create(null);
return {
OperationDefinition: {
enter() {
variableNameDefined = Object.create(null);
},
leave(operation) {
const usages = context.getRecursiveVariableUsages(operation);
for (const { node } of usages) {
const varName = node.name.value;
if (variableNameDefined[varName] !== true) {
context.reportError(
new GraphQLError(
undefinedVarMessage(
varName,
operation.name && operation.name.value,
),
[node, operation],
),
);
}
}
},
},
VariableDefinition(node) {
variableNameDefined[node.variable.name.value] = true;
},
};
}