[−][src]Crate juniper
GraphQL
GraphQL is a data query language developed by Facebook intended to serve mobile and web application frontends.
Juniper makes it possible to write GraphQL servers in Rust that are type-safe and blazingly fast. We also try to make declaring and resolving GraphQL schemas as convenient as possible as Rust will allow.
Juniper does not include a web server - instead it provides building blocks to make integration with existing servers straightforward. It optionally provides a pre-built integration for the Iron and Rocket frameworks, including embedded Graphiql for easy debugging.
- Cargo crate
- API Reference
- Book: Guides and Examples
Getting Started
The best place to get started is the Juniper Book, which contains guides with plenty of examples, covering all features of Juniper.
To get started quickly and get a feel for Juniper, check out the Quickstart section.
For specific information about macros, types and the Juniper api, the API Reference is the best place to look.
You can also check out src/tests/schema.rs to see a complex schema including polymorphism with traits and interfaces. For an example of web framework integration, see the rocket and iron examples folders.
Features
Juniper supports the full GraphQL query language according to the specification, including interfaces, unions, schema introspection, and validations. It does not, however, support the schema language.
As an exception to other GraphQL libraries for other languages, Juniper builds
non-null types by default. A field of type Vec<Episode>
will be converted into
[Episode!]!
. The corresponding Rust type for e.g. [Episode]
would be
Option<Vec<Option<Episode>>>
.
Integrations
Data types
Juniper has automatic integration with some very common Rust crates to make building schemas a breeze. The types from these crates will be usable in your Schemas automatically.
Web Frameworks
API Stability
Juniper has not reached 1.0 yet, thus some API instability should be expected.
Re-exports
pub use http::graphiql; |
Modules
http | Utilities for building HTTP endpoints in a library-agnostic manner |
integrations | Provides GraphQLType implementations for some external types |
meta | Types used to describe a |
parser | Query parser and language utilities |
Macros
graphql_interface | Expose GraphQL interfaces |
graphql_object | Expose GraphQL objects |
graphql_scalar | Expose GraphQL scalars |
graphql_union | Expose GraphQL unions |
graphql_value | Construct JSON-like values by using JSON syntax |
Structs
Arguments | Field argument container |
EmptyMutation | Utility type to define read-only schemas |
ExecutionError | Error type for errors that occur during query execution |
Executor | Query execution engine |
FieldError | Error type for errors that occur during field resolution |
ID | An ID as defined by the GraphQL specification |
LookAheadArgument | An argument passed into the query |
LookAheadSelection | A selection performed by a query |
Object | A Object value |
Registry | A type registry used to build schemas |
RootNode | Root query node of a schema |
RuleError | Query validation error |
Enums
Applies | An enum that describes if a field is available in all types of the interface or only in a certain subtype |
DefaultScalarValue | The default scalar value representation in juniper |
GraphQLError | An error that prevented query execution |
InputValue | A JSON-like value that can be passed into the query execution, either out-of-band, or in-band as default variable values. These are not constant and might contain variables. |
LookAheadValue | A JSON-like value that can is used as argument in the query execution |
Selection | Entry in a GraphQL selection set |
Type | A type literal in the syntax tree |
TypeKind | GraphQL type kind |
Value | Serializable value returned from query and field execution. |
Traits
Context | Marker trait for types that can act as context objects for |
FromContext | Conversion trait for context types |
FromInputValue | Parse an unstructured input value into a Rust data type. |
GraphQLType | Primary trait used to expose Rust types in a GraphQL schema |
IntoFieldError | Custom error handling trait to enable Error types other than |
LookAheadMethods | A set of common methods for |
ParseScalarValue | A trait used to convert a |
ScalarRefValue | A marker trait extending the |
ScalarValue | A trait marking a type that could be used as internal representation of scalar values in juniper |
ToInputValue | Losslessly clones a Rust data type into an InputValue. |
Functions
execute | Execute a query in a provided schema |
Type Definitions
ExecutionResult | The result of resolving an unspecified field |
FieldResult | The result of resolving the value of a field of type |
ParseScalarResult | The result of converting a string into a scalar value |
Variables | The map of variables used for substitution during query execution |