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GraphQL API (Beta)¶
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Overview¶
Version Requirement
GraphQL requires MongoDB version 4.0 or greater.
The Stitch GraphQL API (Beta Release) allows client applications to access data stored in a linked MongoDB cluster using any standard GraphQL client. Stitch automatically creates GraphQL types for every linked collection that has a defined document schema and evaluates role-based permissions for all GraphQL requests.
Create an Atlas Cluster for Free
The GraphQL API lets you access data that you have stored in a MongoDB Atlas cluster. To get started, create a free cluster and link it to your Stitch application.
If you don’t have any data yet but you still want to explore the GraphQL API, consider adding a sample data set to your cluster.
To learn how to make data available through the GraphQL API, see Expose Data in a Collection.
To learn how to connect to the GraphQL API from a client application, see Connect from a Client Application.
To learn how to run queries and mutations from your preferred client, see Execute a GraphQL Operation.
To learn how to define custom queries and mutations, see Define a Custom Query or Mutation.
To learn about the types and operations that you can use with the Stitch GraphQL API, see GraphQL Types & Resolvers.
Why GraphQL?¶
GraphQL is a declarative, strongly-typed query language for client applications. Clients define the exact data shape and contents that they need in a single request which eliminates overfetching problems and circumvents the need for multiple costly round trips to the server.
To learn more about GraphQL, check out the official GraphQL tutorial.
Limitations¶
- The GraphQL API can process a maximum of ten resolvers for a given query or
mutation. If an operation specifies more than ten resolvers, the entire
operation will fail with the error message
"max number of queries reached"
. - The GraphQL API is in a public beta and does not currently support GraphQL subscriptions. We plan to include support for subscriptions and other GraphQL features in future releases.
GraphQL Operations¶
Stitch automatically generates types and resolvers for data that you expose to the GraphQL API. The generated types and operations are all named after the base type name for each exposed collection. If you don’t define a type name, Stitch uses the collection name instead.
For more information on how to expose a collection and name its data type, see Expose Data in a Collection.
Queries¶
A GraphQL query is a read operation that requests specific fields from one or more types. Stitch automatically generates query types for documents in each collection that has a defined schema.
For more information and examples, including a list of all automatically generated query types, see Query Resolvers.
For an example of how to run a query from a client application, see Run a GraphQL Query.
Mutations¶
A GraphQL mutation is a write operation that creates, modifies, or deletes one or more documents. Stitch automatically generates mutation types for documents in each collection that has a defined schema. Stitch uses transactions to ensure safe writes via mutations.
For more information and examples, including a list of all automatically generated mutation types, see Mutation Resolvers.
For an example of how to run a mutation from a client application, see Run a GraphQL Mutation.