README
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Federation plugin
Add support for graphql federation in your graphql Go server!
TODO(miguel): add details.
Tests
There are several different tests. Some will process the configuration file directly. You can see those in the federation_test.go. There are also tests for entity resolvers, which will simulate requests from a federation server like Apollo Federation.
Running entity resolver tests.
- Go to
plugin/federation - Run the command
go generate - Run the tests with
go test ./....
Architecture
TODO(miguel): add details.
Entity resolvers - GetMany entities
The federation plugin implements GetMany semantics in which entity resolvers get the entire list of representations that need to be resolved. This functionality is currently option tho, and to enable it you need to specify the directive @entityResolver in the federated entity you want this feature for. E.g.
directive @entityResolver(multi: Boolean) on OBJECT
type MultiHello @key(fields: "name") @entityResolver(multi: true) {
name: String!
}
That allows the federation plugin to generate GetMany resolver function that can take a list of representations to be resolved.
From that entity type, the resolver function would be
func (r *entityResolver) FindManyMultiHellosByName(ctx context.Context, reps []*generated.ManyMultiHellosByNameInput) ([]*generated.MultiHello, error) {
/// <Your code to resolve the list of items>
}
Note:
If you are using omit_slice_element_pointers: true option in your config yaml, your GetMany resolver will still generate in the example above the same signature FindManyMultiHellosByName(ctx context.Context, reps []*generated.ManyMultiHellosByNameInput) ([]*generated.MultiHello, error). But all other instances will continue to honor omit_slice_element_pointers: true
Documentation
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Index ¶
- Constants
- type Entity
- type EntityResolver
- type Federation
- func (f *Federation) GenerateCode(data *codegen.Data) error
- func (f *Federation) InjectSourcesEarly() ([]*ast.Source, error)
- func (f *Federation) InjectSourcesLate(schema *ast.Schema) ([]*ast.Source, error)
- func (f *Federation) MutateConfig(cfg *config.Config) error
- func (f *Federation) Name() string
- type KeyField
- type PackageOptions
- type Requires
Constants ¶
const DirArgFields = "fields"
The fields arguments must be provided to both key and requires directives.
const DirArgType = "type"
Tells the code generator what type the directive is referencing
const DirNameEntityReference = "entityReference"
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Entity ¶
type Entity struct {
Name string // The same name as the type declaration
Def *ast.Definition
Resolvers []*EntityResolver
Requires []*Requires
Multi bool
Type types.Type
// ImplDirectives are the resolved non-federation OBJECT-level directives
// with full type information, populated in GenerateCode for use in the
// federation template to wrap entity resolver calls.
ImplDirectives []*codegen.Directive
}
Entity represents a federated type that was declared in the GQL schema.
func (Entity) GetTypeInfo ¶ added in v0.17.45
GetTypeInfo - get the imported package & type name combo. package.TypeName
func (*Entity) HasObjectDirectives ¶ added in v0.17.87
HasObjectDirectives reports whether this entity's type definition carries any non-federation user-defined directives that should be applied at runtime when the entity is resolved through the _entities query.
func (*Entity) NonFederationDirectives ¶ added in v0.17.87
func (e *Entity) NonFederationDirectives() ast.DirectiveList
NonFederationDirectives returns the AST directives applied to this entity, excluding federation-internal and gqlgen-internal directives.
type EntityResolver ¶ added in v0.15.0
type EntityResolver struct {
ResolverName string // The resolver name, such as FindUserByID
KeyFields []*KeyField // The fields declared in @key.
InputType types.Type // The Go generated input type for multi entity resolvers
InputTypeName string
ReturnType types.Type // The Go generated return type for the entity
ReturnTypeName string
}
func (*EntityResolver) IsPointerReturnType ¶ added in v0.17.87
func (e *EntityResolver) IsPointerReturnType() bool
IsPointerReturnType returns true if the resolver's return type is a pointer
func (*EntityResolver) LookupInputType ¶ added in v0.17.28
func (e *EntityResolver) LookupInputType() string
func (*EntityResolver) LookupReturnType ¶ added in v0.17.87
func (e *EntityResolver) LookupReturnType() string
type Federation ¶ added in v0.17.54
type Federation struct {
Entities []*Entity
RequiresEntities map[string]*Entity
PackageOptions PackageOptions
// contains filtered or unexported fields
}
func New ¶
func New(version int, cfg *config.Config) (*Federation, error)
New returns a federation plugin that injects federated directives and types into the schema
func (*Federation) GenerateCode ¶ added in v0.17.54
func (f *Federation) GenerateCode(data *codegen.Data) error
func (*Federation) InjectSourcesEarly ¶ added in v0.17.54
func (f *Federation) InjectSourcesEarly() ([]*ast.Source, error)
func (*Federation) InjectSourcesLate ¶ added in v0.17.54
InjectSourcesLate creates a GraphQL Entity type with all the fields that had the @key directive
func (*Federation) MutateConfig ¶ added in v0.17.54
func (f *Federation) MutateConfig(cfg *config.Config) error
MutateConfig mutates the configuration
func (*Federation) Name ¶ added in v0.17.54
func (f *Federation) Name() string
Name returns the plugin name
type KeyField ¶
type KeyField struct {
Definition *ast.FieldDefinition
Field fieldset.Field // len > 1 for nested fields
Type *config.TypeReference // The Go representation of that field type
}
type PackageOptions ¶ added in v0.17.54
type PackageOptions struct {
// ExplicitRequires will generate a function in the execution context
// to populate fields using the @required directive into the entity.
//
// You can only set one of ExplicitRequires or ComputedRequires to true.
ExplicitRequires bool
// ComputedRequires generates resolver functions to compute values for
// fields using the @required directive.
ComputedRequires bool
// EntityResolverMulti is default engine for entityResolver generation.
// This can be overriding by @entityResolver(multi: Boolean) directive.
// false by default.
EntityResolverMulti bool
}
Source Files
Directories