Hoist Field Transform#

The hoist transform allows you to lift a field from one object type to a 'parent' root or object type. It is currently only available as a wrap transform.

yarn add @graphql-mesh/transform-hoist-field

Underneath it leverages the HoistField transform from the @graphql-tools/wrap package.

How to use?#

Given the following schema:

type Query {
 users(limit: Int!, page: Int): UserSearchResult
}

type UserSearchResult {
 page: Int!
 results: [User!]!
}

type User {
 id: ID!
}

Simple hoisting#

transforms:
 - hoist:
 - typeName: Query
 pathConfig:
 - users
 - results
 newFieldName: users

Will transform the given schema to:

type Query {
 users(limit: Int!, page: Int): [User!]!
}

type User {
 id: ID!
}

Filtering args via a default for the entire path#

transforms:
 - hoist:
 - typeName: Query
 pathConfig:
 - users
 - results
 newFieldName: users
 filterArgsInPath: true # This flag sets the default for the entire path

Will transform the given schema to:

type Query {
 users: [User!]!
}

type User {
 id: ID!
}

Filtering args via on specific levels of the path#

transforms:
 - hoist:
 - typeName: Query
 pathConfig:
 - fieldName: users
 filterArgs:
 - limit
 - results
 newFieldName: users

Will transform the given schema to:

type Query {
 users(page: Int): [User!]!
}

type User {
 id: ID!
}

Config API Reference#

field (type: String, required) - The type and field to apply cache to, you can use wild cards as well, for example: Query.*
cacheKey (type: String) - Cache key to use to store your resolvers responses. The default is: {typeName}-{fieldName}-{argsHash}-{fieldNamesHash}

Available variables:

{args.argName} - use resolver argument
{typeName} - use name of the type
{fieldName} - use name of the field
{argsHash} - a hash based on the 'args' object
{fieldNamesHash} - a hash based on the field names selected by the client
{info} - the GraphQLResolveInfo of the resolver

Available interpolations:

{format|date} - returns the current date with a specific format

invalidate (type: Object) - Invalidation rules:
- effectingOperations (type: Array of Object, required) - Invalidate the cache when a specific operation is done without an error:
  - operation (type: String, required) - Path to the operation that could effect it. In a form: Mutation.something. Note that wildcard is not supported in this field.
  - matchKey (type: String) - Cache key to invalidate on successful resolver (no error), see cacheKey for list of available options in this field.
- ttl (type: Int) - Specified in seconds, the time-to-live (TTL) value limits the lifespan