Operation name

The identifier is the first argument to any graphql.* method. Mock Config checks it against three things from the incoming request — the operation name, the full query document, and the event name — in that order. The first match wins.

Operation Name

The most common way to match. Pass a string equal to the name declared after query, mutation, or subscription in the document:

graphql.query('GetUsers', { data: { users: [] } });

For the query:

query GetUsers {
  users {
    id
    name
  }
}

The operation name is GetUsers. This is what most clients send via the operationName field in the request payload.

Full Query Document

Pass the full query string as the identifier to match by the exact shape of the document, regardless of the operation name:

graphql.query(
  `query GetUsers {
    users { id name }
  }`,
  { data: { users: [] } }
);

Queries are normalized before comparison (whitespace stripped), so formatting differences do not affect matching. Useful when clients do not set an operationName.

Event Name

The identifier is also compared against the first field in the selection set — called the event name. This allows matching operations that share a root field even if their operation names differ:

graphql.query('users', { data: { users: [] } });

For this query:

query GetUsers {
  users {
    id
    name
  }
}

The event name is users. Useful when the client sends queries without an explicit operationName.

Regular Expressions

A RegExp identifier is tested against all three values — operation name, full query, and event name. The handler matches if the expression satisfies any of them:

graphql.query(/^Get/, { data: {} });
graphql.query(/users/, { data: { users: [] } });

Priority

A string identifier is always more specific than a RegExp. When multiple handlers match, the most specific wins:

graphql.query('GetUsers', { data: { users: [] } });
graphql.query(/^Get/, { data: {} });

A GetUsers request matches the first handler. Any other operation starting with Get matches the second.