Documentation
¶
Overview ¶
Package grpcdatasource provides a GraphQL datasource implementation for gRPC services. It allows GraphQL servers to connect to gRPC backends and execute RPC calls as part of GraphQL query resolution.
The package includes tools for parsing Protobuf definitions, building execution plans, and converting GraphQL queries into gRPC requests.
Index ¶
- type DataSource
- type DataSourceConfig
- type DataType
- type Document
- func (d *Document) EnumByName(name string) (Enum, bool)
- func (d *Document) MessageByName(name string) Message
- func (d *Document) MessageByRef(ref int) Message
- func (d *Document) MessageRefByName(name string) int
- func (d *Document) MethodByName(name string) Method
- func (d *Document) MethodByRef(ref int) Method
- func (d *Document) MethodRefByName(name string) int
- func (d *Document) ServiceByName(name string) Service
- func (d *Document) ServiceByRef(ref int) Service
- type EntityRPCConfig
- type Enum
- type EnumValue
- type EnumValueMapping
- type Field
- type FieldArgumentMap
- type FieldMap
- type FieldMapData
- type GRPCConfiguration
- type GRPCMapping
- type Invocation
- type Message
- type Method
- type Planner
- type ProtoConfig
- type RPCCall
- type RPCCompiler
- type RPCConfig
- type RPCConfigMap
- type RPCExecutionPlan
- type RPCField
- type RPCFields
- type RPCMessage
- type Service
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type DataSource ¶
type DataSource struct {
// contains filtered or unexported fields
}
DataSource implements the resolve.DataSource interface for gRPC services. It handles the conversion of GraphQL queries to gRPC requests and transforms the responses back to GraphQL format.
func NewDataSource ¶
func NewDataSource(client grpc.ClientConnInterface, config DataSourceConfig) (*DataSource, error)
NewDataSource creates a new gRPC datasource
func (*DataSource) Load ¶
Load implements resolve.DataSource interface. It processes the input JSON data to make gRPC calls and writes the response to the output buffer.
The input is expected to contain the necessary information to make a gRPC call, including service name, method name, and request data.
func (*DataSource) LoadWithFiles ¶
func (d *DataSource) LoadWithFiles(ctx context.Context, input []byte, files []*httpclient.FileUpload, out *bytes.Buffer) (err error)
LoadWithFiles implements resolve.DataSource interface. Similar to Load, but handles file uploads if needed.
Note: File uploads are typically not part of gRPC, so this method might not be applicable for most gRPC use cases.
Currently unimplemented.
type DataSourceConfig ¶
type DataSourceConfig struct {
Operation *ast.Document
Definition *ast.Document
Compiler *RPCCompiler
SubgraphName string
Mapping *GRPCMapping
Disabled bool
}
type DataType ¶
type DataType string
DataType represents the different types of data that can be stored in a protobuf field.
const ( DataTypeString DataType = "string" // String type DataTypeInt32 DataType = "int32" // 32-bit integer type DataTypeInt64 DataType = "int64" // 64-bit integer type DataTypeUint32 DataType = "uint32" // 32-bit unsigned integer type DataTypeUint64 DataType = "uint64" // 64-bit unsigned integer type DataTypeFloat DataType = "float" // 32-bit floating point type DataTypeDouble DataType = "double" // 64-bit floating point type DataTypeBool DataType = "bool" // Boolean type DataTypeEnum DataType = "enum" // Enumeration type DataTypeMessage DataType = "message" // Nested message type DataTypeUnknown DataType = "<unknown>" // Represents an unknown or unsupported type DataTypeBytes DataType = "bytes" // Bytes type )
Protobuf data types supported by the compiler.
type Document ¶
type Document struct {
Package string // The package name of the protobuf document
Services []Service // All services defined in the document
Enums []Enum // All enums defined in the document
Messages []Message // All messages defined in the document
Methods []Method // All methods from all services in the document
}
Document represents a compiled protobuf document with all its services, messages, and methods.
func (*Document) MessageByName ¶
MessageByName returns a Message by its name. Returns an empty Message if no message with the given name exists.
func (*Document) MessageByRef ¶
MessageByRef returns a Message by its reference index.
func (*Document) MessageRefByName ¶
MessageRefByName returns the index of a Message in the Messages slice by its name. Returns -1 if no message with the given name exists.
func (*Document) MethodByName ¶
MethodByName returns a Method by its name. Returns an empty Method if no method with the given name exists.
func (*Document) MethodByRef ¶
MethodByRef returns a Method by its reference index.
func (*Document) MethodRefByName ¶
MethodRefByName returns the index of a Method in the Methods slice by its name. Returns -1 if no method with the given name exists.
func (*Document) ServiceByName ¶
ServiceByName returns a Service by its name. Returns an empty Service if no service with the given name exists.
func (*Document) ServiceByRef ¶
ServiceByRef returns a Service by its reference index.
type EntityRPCConfig ¶
type EntityRPCConfig struct {
// Key is a list of field names that uniquely identify the entity
Key string
// RPCConfig is the embedded configuration for the RPC operation
RPCConfig
}
EntityRPCConfig defines the configuration for entity lookups
type Enum ¶
type Enum struct {
Name string // The name of the enum
Values []EnumValue // The values in the enum
}
Enum represents a protobuf enum type with its values.
type EnumValue ¶
type EnumValue struct {
Name string // The name of the enum value
GraphqlValue string // The target value of the enum value
Number int32 // The numeric value of the enum value
}
EnumValue represents a single value in a protobuf enum.
type EnumValueMapping ¶
type Field ¶
type Field struct {
Name string // The name of the field
Type DataType // The data type of the field
Number int32 // The field number in the protobuf message
Ref int // Reference to the field (used for complex types)
Repeated bool // Whether the field is a repeated field (array/list)
Optional bool // Whether the field is optional
MessageRef int // If the field is a message type, this points to the message definition
}
Field represents a field in a protobuf message.
func (*Field) ResolveUnderlyingMessage ¶
type FieldArgumentMap ¶
FieldArgumentMap defines the mapping between a GraphQL field argument and a gRPC field
type FieldMap ¶
type FieldMap map[string]FieldMapData
FieldMap defines the mapping between a GraphQL field and a gRPC field
type FieldMapData ¶
type FieldMapData struct {
TargetName string
ArgumentMappings FieldArgumentMap
}
type GRPCConfiguration ¶
type GRPCConfiguration struct {
Disabled bool
Mapping *GRPCMapping
Compiler *RPCCompiler
}
type GRPCMapping ¶
type GRPCMapping struct {
// Service is the name of the gRPC service to use
Service string
// QueryRPCs maps GraphQL query fields to the corresponding gRPC RPC configurations
QueryRPCs RPCConfigMap
// MutationRPCs maps GraphQL mutation fields to the corresponding gRPC RPC configurations
MutationRPCs RPCConfigMap
// SubscriptionRPCs maps GraphQL subscription fields to the corresponding gRPC RPC configurations
SubscriptionRPCs RPCConfigMap
// EntityRPCs defines how GraphQL types are resolved as entities using specific RPCs
EntityRPCs map[string]EntityRPCConfig
// Fields defines the field mappings between GraphQL types and gRPC messages
Fields map[string]FieldMap
// EnumValues defines the enum values for each enum type
EnumValues map[string][]EnumValueMapping
}
func (*GRPCMapping) ResolveEnumValue ¶
func (g *GRPCMapping) ResolveEnumValue(enumName, enumValue string) (string, bool)
func (*GRPCMapping) ResolveFieldArgumentMapping ¶
func (g *GRPCMapping) ResolveFieldArgumentMapping(typeName, fieldName, argumentName string) (string, bool)
func (*GRPCMapping) ResolveFieldMapping ¶
func (g *GRPCMapping) ResolveFieldMapping(typeName string, fieldName string) (string, bool)
ResolveFieldMapping resolves the gRPC field name for a given GraphQL field name and type
type Invocation ¶
type Invocation struct {
ServiceName string
MethodName string
Input *dynamicpb.Message
Output *dynamicpb.Message
Call *RPCCall
}
Invocation represents a single gRPC invocation with its input and output messages.
type Message ¶
type Message struct {
Name string // The name of the message
Fields []Field // The fields in the message
Desc protoref.MessageDescriptor // The protobuf descriptor for the message
}
Message represents a protobuf message type with its fields.
type Method ¶
type Method struct {
Name string // The name of the method
InputName string // The name of the input message type
InputRef int // Reference to the input message in the Document.Messages slice
OutputName string // The name of the output message type
OutputRef int // Reference to the output message in the Document.Messages slice
}
Method represents a gRPC method with input and output message types.
type Planner ¶
type Planner struct {
// contains filtered or unexported fields
}
func NewPlanner ¶
func NewPlanner(subgraphName string, mapping *GRPCMapping) *Planner
NewPlanner returns a new Planner instance.
The planner is responsible for creating an RPCExecutionPlan from a given GraphQL operation. It is used by the engine to execute operations against gRPC services.
func (*Planner) PlanOperation ¶
func (p *Planner) PlanOperation(operation, definition *ast.Document) (*RPCExecutionPlan, error)
type ProtoConfig ¶
type ProtoConfig struct {
Schema string
}
type RPCCall ¶
type RPCCall struct {
// CallID is the unique identifier for the call
CallID int
// DependentCalls is a list of calls that must be executed before this call
DependentCalls []int
// ServiceName is the name of the gRPC service to call
ServiceName string
// MethodName is the name of the method on the service to call
MethodName string
// Request contains the message structure for the gRPC request
Request RPCMessage
// Response contains the message structure for the gRPC response
Response RPCMessage
}
RPCCall represents a single call to a gRPC service method. It contains all the information needed to make the call and process the response.
type RPCCompiler ¶
type RPCCompiler struct {
Ancestor []Message
// contains filtered or unexported fields
}
RPCCompiler compiles protobuf schema strings into a Document and can build protobuf messages from JSON data based on the schema.
func NewProtoCompiler ¶
func NewProtoCompiler(schema string, mapping *GRPCMapping) (*RPCCompiler, error)
NewProtoCompiler compiles the protobuf schema into a Document structure. It extracts information about services, methods, messages, and enums from the protobuf schema.
func (*RPCCompiler) Compile ¶
func (p *RPCCompiler) Compile(executionPlan *RPCExecutionPlan, inputData gjson.Result) ([]Invocation, error)
Compile processes an RPCExecutionPlan and builds protobuf messages from JSON data based on the compiled schema.
func (*RPCCompiler) ConstructExecutionPlan ¶
func (p *RPCCompiler) ConstructExecutionPlan(operation, schema *ast.Document) (*RPCExecutionPlan, error)
ConstructExecutionPlan constructs an RPCExecutionPlan from a parsed GraphQL operation and schema. It will return an error if the operation does not match the protobuf definition provided to the compiler.
type RPCConfig ¶
type RPCConfig struct {
// RPC is the name of the RPC method to call
RPC string
// Request is the name of the request message type
Request string
// Response is the name of the response message type
Response string
}
RPCConfig defines the configuration for a specific RPC operation
type RPCConfigMap ¶
RPCConfigMap is a map of RPC names to RPC configurations
type RPCExecutionPlan ¶
type RPCExecutionPlan struct {
// Calls is a list of gRPC calls that are executed in the same group
Calls []RPCCall
}
RPCExecutionPlan represents a plan for executing one or more RPC calls to gRPC services. It defines the sequence of calls and their dependencies.
func (*RPCExecutionPlan) String ¶
func (r *RPCExecutionPlan) String() string
type RPCField ¶
type RPCField struct {
// Alias can be used to rename the field in the request message
// This is needed to make sure that during the json composition,
// the field names match the GraphQL request naming.
// TODO implement alias handling
Alias string
// Repeated indicates if the field is a repeated field (array/list)
Repeated bool
// Name is the name of the field as defined in the protobuf message
Name string
// TypeName is the name of the type of the field in the protobuf definition
TypeName string
// JSONPath defines the path within the variables to provide the value for the field
// This is used to extract data from the GraphQL variables
JSONPath string
// EnumName is the name of the enum if the field is an enum type
EnumName string
// StaticValue is the static value of the field
StaticValue string
// Message is the message type if the field is a nested message type
// This allows for recursive construction of complex message types
Message *RPCMessage
}
RPCField represents a single field in a gRPC message. It contains all information required to extract data from GraphQL variables and construct the appropriate protobuf field.
type RPCFields ¶
type RPCFields []RPCField
RPCFields is a list of RPCFields that provides helper methods for working with collections of fields.
type RPCMessage ¶
type RPCMessage struct {
// Name is the name of the message type in the protobuf definition
Name string
// Fields is a list of fields in the message
Fields RPCFields
// OneOf indicates if the message is an interface
OneOf bool
}
RPCMessage represents a gRPC message structure for requests and responses. It defines the structure of the message including all its fields.