32 lines
1016 B
Plaintext
32 lines
1016 B
Plaintext
// @flow strict
|
|
import type { DocumentNode, OperationDefinitionNode } from '../language/ast';
|
|
import { Kind } from '../language/kinds';
|
|
|
|
/**
|
|
* Returns an operation AST given a document AST and optionally an operation
|
|
* name. If a name is not provided, an operation is only returned if only one is
|
|
* provided in the document.
|
|
*/
|
|
export function getOperationAST(
|
|
documentAST: DocumentNode,
|
|
operationName?: ?string,
|
|
): ?OperationDefinitionNode {
|
|
let operation = null;
|
|
for (const definition of documentAST.definitions) {
|
|
if (definition.kind === Kind.OPERATION_DEFINITION) {
|
|
if (operationName == null) {
|
|
// If no operation name was provided, only return an Operation if there
|
|
// is one defined in the document. Upon encountering the second, return
|
|
// null.
|
|
if (operation) {
|
|
return null;
|
|
}
|
|
operation = definition;
|
|
} else if (definition.name?.value === operationName) {
|
|
return definition;
|
|
}
|
|
}
|
|
}
|
|
return operation;
|
|
}
|