| // @flow strict |
| |
| import { Kind } from '../language/kinds'; |
| import { |
| type DocumentNode, |
| type OperationDefinitionNode, |
| } from '../language/ast'; |
| |
| /** |
| * 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; |
| } |