rpc

package
v0.0.8 Latest Latest
Warning

This package is not in the latest version of its module.

 Go to latest Published: Apr 29, 2024 License: MIT Imports: 28 Imported by: 0

Documentation

Index

Constants

View Source 
const EngineApi = "engine"
View Source 
const MetadataApi = "rpc"

Variables

View Source 
var (
	ErrBadResult                 = errors.New("bad result in JSON-RPC response")
	ErrClientQuit                = errors.New("client is closed")
	ErrNoResult                  = errors.New("JSON-RPC response has no result")
	ErrMissingBatchResponse      = errors.New("response batch did not contain a response to this call")
	ErrSubscriptionQueueOverflow = errors.New("subscription queue overflow")
)
View Source 
var (
	// ErrNotificationsUnsupported is returned by the client when the connection doesn't
	// support notifications. You can use this error value to check for subscription
	// support like this:
	//
	//	sub, err := client.EthSubscribe(ctx, channel, "newHeads", true)
	//	if errors.Is(err, rpc.ErrNotificationsUnsupported) {
	//		// Server does not support subscriptions, fall back to polling.
	//	}
	//
	ErrNotificationsUnsupported = notificationsUnsupportedError{}

	// ErrSubscriptionNotFound is returned when the notification for the given id is not found
	ErrSubscriptionNotFound = errors.New("subscription not found")
)
View Source 
var DefaultHTTPTimeouts = HTTPTimeouts{
	ReadTimeout:       30 * time.Second,
	ReadHeaderTimeout: 30 * time.Second,
	WriteTimeout:      30 * time.Second,
	IdleTimeout:       120 * time.Second,
}

DefaultHTTPTimeouts represents the default timeout values used if further configuration is not provided.

Functions

func ContextRequestTimeout 

func ContextRequestTimeout(ctx context.Context) (time.Duration, bool)

ContextRequestTimeout returns the request timeout derived from the given context.

func NewContextWithHeaders 

func NewContextWithHeaders(ctx context.Context, h http.Header) context.Context

NewContextWithHeaders wraps the given context, adding HTTP headers. These headers will be applied by Client when making a request using the returned context.

Types

type BatchElem added in v0.0.3 

type BatchElem struct {
	Method string
	Args   []interface{}
	// The result is unmarshaled into this field. Result must be set to a
	// non-nil pointer value of the desired type, otherwise the response will be
	// discarded.
	Result interface{}
	// Error is set if the server returns an error for this request, or if
	// unmarshaling into Result fails. It is not set for I/O errors.
	Error error
}

BatchElem is an element in a batch request.

type Client 

type Client struct {
	IsDebug bool // debug rpc request
	// contains filtered or unexported fields
}

Client represents a connection to an RPC server.

func ClientFromContext 

func ClientFromContext(ctx context.Context) (*Client, bool)

ClientFromContext retrieves the client from the context, if any. This can be used to perform 'reverse calls' in a handler method.

func Dial 

func Dial(rawurl string) (*Client, error)

Dial creates a new client for the given URL.

The currently supported URL schemes are "http", "https", "ws" and "wss". If rawurl is a file name with no URL scheme, a local socket connection is established using UNIX domain sockets on supported platforms and named pipes on Windows.

If you want to further configure the transport, use DialOptions instead of this function.

For websocket connections, the origin is set to the local host name.

The client reconnects automatically when the connection is lost.

func DialContext 

func DialContext(ctx context.Context, rawurl string) (*Client, error)

DialContext creates a new RPC client, just like Dial.

The context is used to cancel or time out the initial connection establishment. It does not affect subsequent interactions with the client.

func DialHTTP added in v0.0.3 

func DialHTTP(endpoint string) (*Client, error)

DialHTTP creates a new RPC client that connects to an RPC server over HTTP.

func DialHTTPWithClient deprecated added in v0.0.3 

func DialHTTPWithClient(endpoint string, client *http.Client) (*Client, error)

DialHTTPWithClient creates a new RPC client that connects to an RPC server over HTTP using the provided HTTP Client.

Deprecated: use DialOptions and the WithHTTPClient option.

func DialOptions 

func DialOptions(ctx context.Context, rawurl string, options ...ClientOption) (*Client, error)

DialOptions creates a new RPC client for the given URL. You can supply any of the pre-defined client options to configure the underlying transport.

The context is used to cancel or time out the initial connection establishment. It does not affect subsequent interactions with the client.

The client reconnects automatically when the connection is lost.

func DialWebsocket added in v0.0.3 

func DialWebsocket(ctx context.Context, endpoint, origin string) (*Client, error)

DialWebsocket creates a new RPC client that communicates with a JSON-RPC server that is listening on the given endpoint.

The context is used for the initial connection establishment. It does not affect subsequent interactions with the client.

func DialWebsocketWithDialer deprecated added in v0.0.3 

func DialWebsocketWithDialer(ctx context.Context, endpoint, origin string, dialer websocket.Dialer) (*Client, error)

DialWebsocketWithDialer creates a new RPC client using WebSocket.

The context is used for the initial connection establishment. It does not affect subsequent interactions with the client.

Deprecated: use DialOptions and the WithWebsocketDialer option.

func (*Client) BatchCall added in v0.0.3 

func (c *Client) BatchCall(b []BatchElem) error

BatchCall sends all given requests as a single batch and waits for the server to return a response for all of them.

In contrast to Call, BatchCall only returns I/O errors. Any error specific to a request is reported through the Error field of the corresponding BatchElem.

Note that batch calls may not be executed atomically on the server side.

func (*Client) BatchCallContext added in v0.0.3 

func (c *Client) BatchCallContext(ctx context.Context, b []BatchElem) error

BatchCallContext sends all given requests as a single batch and waits for the server to return a response for all of them. The wait duration is bounded by the context's deadline.

In contrast to CallContext, BatchCallContext only returns errors that have occurred while sending the request. Any error specific to a request is reported through the Error field of the corresponding BatchElem.

Note that batch calls may not be executed atomically on the server side.

func (*Client) Call 

func (c *Client) Call(result interface{}, method string, args ...interface{}) error

Call performs a JSON-RPC call with the given arguments and unmarshals into result if no error occurred.

The result must be a pointer so that package json can unmarshal into it. You can also pass nil, in which case the result is ignored.

func (*Client) CallContext 

func (c *Client) CallContext(ctx context.Context, result interface{}, method string, args ...interface{}) error

CallContext performs a JSON-RPC call with the given arguments. If the context is canceled before the call has successfully returned, CallContext returns immediately.

The result must be a pointer so that package json can unmarshal into it. You can also pass nil, in which case the result is ignored.

func (*Client) Close 

func (c *Client) Close()

Close closes the client, aborting any in-flight requests.

func (*Client) Notify added in v0.0.3 

func (c *Client) Notify(ctx context.Context, method string, args ...interface{}) error

Notify sends a notification, i.e. a method call that doesn't expect a response.

func (*Client) RegisterName added in v0.0.3 

func (c *Client) RegisterName(name string, receiver interface{}) error

RegisterName creates a service for the given receiver type under the given name. When no methods on the given receiver match the criteria to be either a RPC method or a subscription an error is returned. Otherwise a new service is created and added to the service collection this client provides to the server.

func (*Client) SetHeader 

func (c *Client) SetHeader(key, value string)

SetHeader adds a custom HTTP header to the client's requests. This method only works for clients using HTTP, it doesn't have any effect for clients using another transport.

func (*Client) Subscribe added in v0.0.3 

func (c *Client) Subscribe(ctx context.Context, namespace string, channel interface{}, args ...interface{}) (*ClientSubscription, error)

Subscribe calls the "<namespace>_Subscribe" method with the given arguments, registering a subscription. Server notifications for the subscription are sent to the given channel. The element type of the channel must match the expected type of content returned by the subscription.

The context argument cancels the RPC request that sets up the subscription but has no effect on the subscription after Subscribe has returned.

Slow subscribers will be dropped eventually. Client buffers up to 20000 notifications before considering the subscriber dead. The subscription Err channel will receive ErrSubscriptionQueueOverflow. Use a sufficiently large buffer on the channel or ensure that the channel usually has at least one reader to prevent this issue.

func (*Client) SupportedModules added in v0.0.3 

func (c *Client) SupportedModules() (map[string]string, error)

SupportedModules calls the rpc_modules method, retrieving the list of APIs that are available on the server.

func (*Client) SupportsSubscriptions added in v0.0.3 

func (c *Client) SupportsSubscriptions() bool

SupportsSubscriptions reports whether subscriptions are supported by the client transport. When this returns false, Subscribe and related methods will return ErrNotificationsUnsupported.

type ClientOption 

type ClientOption interface {
	// contains filtered or unexported methods
}

ClientOption is a configuration option for the RPC client.

func WithBatchItemLimit 

func WithBatchItemLimit(limit int) ClientOption

WithBatchItemLimit changes the maximum number of items allowed in batch requests.

Note: this option applies when processing incoming batch requests. It does not affect batch requests sent by the client.

func WithBatchResponseSizeLimit 

func WithBatchResponseSizeLimit(sizeLimit int) ClientOption

WithBatchResponseSizeLimit changes the maximum number of response bytes that can be generated for batch requests. When this limit is reached, further calls in the batch will not be processed.

Note: this option applies when processing incoming batch requests. It does not affect batch requests sent by the client.

func WithHTTPAuth 

func WithHTTPAuth(a HTTPAuth) ClientOption

WithHTTPAuth configures HTTP request authentication. The given provider will be called whenever a request is made. Note that only one authentication provider can be active at any time.

func WithHTTPClient 

func WithHTTPClient(c *http.Client) ClientOption

WithHTTPClient configures the http.Client used by the RPC client.

func WithHeader 

func WithHeader(key, value string) ClientOption

WithHeader configures HTTP headers set by the RPC client. Headers set using this option will be used for both HTTP and WebSocket connections.

func WithHeaders 

func WithHeaders(headers http.Header) ClientOption

WithHeaders configures HTTP headers set by the RPC client. Headers set using this option will be used for both HTTP and WebSocket connections.

type ClientSubscription added in v0.0.3 

type ClientSubscription struct {
	// contains filtered or unexported fields
}

ClientSubscription is a subscription established through the Client's Subscribe or EthSubscribe methods.

func (*ClientSubscription) Err added in v0.0.3 

func (sub *ClientSubscription) Err() <-chan error

Err returns the subscription error channel. The intended use of Err is to schedule resubscription when the client connection is closed unexpectedly.

The error channel receives a value when the subscription has ended due to an error. The received error is nil if Close has been called on the underlying client and no other error has occurred.

The error channel is closed when Unsubscribe is called on the subscription.

func (*ClientSubscription) Unsubscribe added in v0.0.3 

func (sub *ClientSubscription) Unsubscribe()

Unsubscribe unsubscribes the notification and closes the error channel. It can safely be called more than once.

type CodecOption deprecated added in v0.0.3 

type CodecOption int

CodecOption specifies which type of messages a codec supports.

Deprecated: this option is no longer honored by Server. 

const (
	// OptionMethodInvocation is an indication that the codec supports RPC method calls
	OptionMethodInvocation CodecOption = 1 << iota

	// OptionSubscriptions is an indication that the codec supports RPC notifications
	OptionSubscriptions = 1 << iota // support pub sub
)

type Conn 

type Conn interface {
	io.ReadWriteCloser
	SetWriteDeadline(time.Time) error
}

Conn is a subset of the methods of net.Conn which are sufficient for ServerCodec.

type ConnRemoteAddr 

type ConnRemoteAddr interface {
	RemoteAddr() string
}

ConnRemoteAddr wraps the RemoteAddr operation, which returns a description of the peer address of a connection. If a Conn also implements ConnRemoteAddr, this description is used in log messages.

type DataError 

type DataError interface {
	Error() string          // returns the message
	ErrorData() interface{} // returns the error data
}

A DataError contains some data in addition to the error message.

type Error 

type Error interface {
	Error() string  // returns the message
	ErrorCode() int // returns the code
}

Error wraps RPC errors, which contain an error code in addition to the message.

type HTTPAuth 

type HTTPAuth func(h http.Header) error

A HTTPAuth function is called by the client whenever a HTTP request is sent. The function must be safe for concurrent use.

Usually, HTTPAuth functions will call h.Set("authorization", "...") to add auth information to the request.

type HTTPError 

type HTTPError struct {
	StatusCode int
	Status     string
	Body       []byte
}

HTTPError is returned by client operations when the HTTP status code of the response is not a 2xx status.

func (HTTPError) Error 

func (err HTTPError) Error() string

type HTTPTimeouts 

type HTTPTimeouts struct {
	// ReadTimeout is the maximum duration for reading the entire
	// request, including the body.
	//
	// Because ReadTimeout does not let Handlers make per-request
	// decisions on each request body's acceptable deadline or
	// upload rate, most users will prefer to use
	// ReadHeaderTimeout. It is valid to use them both.
	ReadTimeout time.Duration

	// ReadHeaderTimeout is the amount of time allowed to read
	// request headers. The connection's read deadline is reset
	// after reading the headers and the Handler can decide what
	// is considered too slow for the body. If ReadHeaderTimeout
	// is zero, the value of ReadTimeout is used. If both are
	// zero, there is no timeout.
	ReadHeaderTimeout time.Duration

	// WriteTimeout is the maximum duration before timing out
	// writes of the response. It is reset whenever a new
	// request's header is read. Like ReadTimeout, it does not
	// let Handlers make decisions on a per-request basis.
	WriteTimeout time.Duration

	// IdleTimeout is the maximum amount of time to wait for the
	// next request when keep-alives are enabled. If IdleTimeout
	// is zero, the value of ReadTimeout is used. If both are
	// zero, ReadHeaderTimeout is used.
	IdleTimeout time.Duration
}

HTTPTimeouts represents the configuration params for the HTTP RPC server.

type ID added in v0.0.3 

type ID string

ID defines a pseudo random number that is used to identify RPC subscriptions.

func NewID added in v0.0.3 

func NewID() ID

NewID returns a new, random ID.

type Notifier added in v0.0.3 

type Notifier struct {
	// contains filtered or unexported fields
}

Notifier is tied to a RPC connection that supports subscriptions. Server callbacks use the notifier to send notifications.

func NotifierFromContext added in v0.0.3 

func NotifierFromContext(ctx context.Context) (*Notifier, bool)

NotifierFromContext returns the Notifier value stored in ctx, if any.

func (*Notifier) Closed added in v0.0.3 

func (n *Notifier) Closed() <-chan interface{}

Closed returns a channel that is closed when the RPC connection is closed. Deprecated: use subscription error channel

func (*Notifier) CreateSubscription added in v0.0.3 

func (n *Notifier) CreateSubscription() *Subscription

CreateSubscription returns a new subscription that is coupled to the RPC connection. By default subscriptions are inactive and notifications are dropped until the subscription is marked as active. This is done by the RPC server after the subscription ID is send to the client.

func (*Notifier) Notify added in v0.0.3 

func (n *Notifier) Notify(id ID, data any) error

Notify sends a notification to the client with the given data as payload. If an error occurs the RPC connection is closed and the error is returned.

type PeerInfo added in v0.0.3 

type PeerInfo struct {
	// Transport is name of the protocol used by the client.
	// This can be "http", "ws" or "ipc".
	Transport string

	// Address of client. This will usually contain the IP address and port.
	RemoteAddr string

	// Additional information for HTTP and WebSocket connections.
	HTTP struct {
		// Protocol version, i.e. "HTTP/1.1". This is not set for WebSocket.
		Version string
		// Header values sent by the client.
		UserAgent string
		Origin    string
		Host      string
	}
}

PeerInfo contains information about the remote end of the network connection.

This is available within RPC method handlers through the context. Call PeerInfoFromContext to get information about the client connection related to the current method call.

func PeerInfoFromContext added in v0.0.3 

func PeerInfoFromContext(ctx context.Context) PeerInfo

PeerInfoFromContext returns information about the client's network connection. Use this with the context passed to RPC method handler functions.

The zero value is returned if no connection info is present in ctx.

type RPCService added in v0.0.3 

type RPCService struct {
	// contains filtered or unexported fields
}

RPCService gives meta information about the server. e.g. gives information about the loaded modules.

func (*RPCService) Modules added in v0.0.3 

func (s *RPCService) Modules() map[string]string

Modules returns the list of RPC services with their version number

type Server added in v0.0.3 

type Server struct {
	// contains filtered or unexported fields
}

Server is an RPC server.

func NewServer added in v0.0.3 

func NewServer() *Server

NewServer creates a new server instance with no registered handlers.

func (*Server) RegisterName added in v0.0.3 

func (s *Server) RegisterName(name string, receiver interface{}) error

RegisterName creates a service for the given receiver type under the given name. When no methods on the given receiver match the criteria to be either a RPC method or a subscription an error is returned. Otherwise a new service is created and added to the service collection this server provides to clients.

func (*Server) ServeCodec added in v0.0.3 

func (s *Server) ServeCodec(codec ServerCodec, options CodecOption)

ServeCodec reads incoming requests from codec, calls the appropriate callback and writes the response back using the given codec. It will block until the codec is closed or the server is stopped. In either case the codec is closed.

Note that codec options are no longer supported.

func (*Server) ServeHTTP added in v0.0.3 

func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request)

ServeHTTP serves JSON-RPC requests over HTTP.

func (*Server) SetBatchLimits added in v0.0.3 

func (s *Server) SetBatchLimits(itemLimit, maxResponseSize int)

SetBatchLimits sets limits applied to batch requests. There are two limits: 'itemLimit' is the maximum number of items in a batch. 'maxResponseSize' is the maximum number of response bytes across all requests in a batch.

This method should be called before processing any requests via ServeCodec, ServeHTTP, ServeListener etc.

func (*Server) SetHTTPBodyLimit added in v0.0.3 

func (s *Server) SetHTTPBodyLimit(limit int)

SetHTTPBodyLimit sets the size limit for HTTP requests.

This method should be called before processing any requests via ServeHTTP.

func (*Server) Stop added in v0.0.3 

func (s *Server) Stop()

Stop stops reading new requests, waits for stopPendingRequestTimeout to allow pending requests to finish, then closes all codecs which will cancel pending requests and subscriptions.

func (*Server) WebsocketHandler added in v0.0.3 

func (s *Server) WebsocketHandler(allowedOrigins []string) http.Handler

WebsocketHandler returns a handler that serves JSON-RPC to WebSocket connections.

allowedOrigins should be a comma-separated list of allowed origin URLs. To allow connections with any origin, pass "*".

type ServerCodec 

type ServerCodec interface {
	// contains filtered or unexported methods
}

ServerCodec implements reading, parsing and writing RPC messages for the server side of a RPC session. Implementations must be go-routine safe since the codec can be called in multiple go-routines concurrently.

func NewCodec 

func NewCodec(conn Conn) ServerCodec

NewCodec creates a codec on the given connection. If conn implements ConnRemoteAddr, log messages will use it to include the remote address of the connection.

func NewFuncCodec 

func NewFuncCodec(conn deadlineCloser, encode encodeFunc, decode decodeFunc) ServerCodec

NewFuncCodec creates a codec which uses the given functions to read and write. If conn implements ConnRemoteAddr, log messages will use it to include the remote address of the connection.

type Subscription added in v0.0.3 

type Subscription struct {
	ID ID
	// contains filtered or unexported fields
}

A Subscription is created by a notifier and tied to that notifier. The client can use this subscription to wait for an unsubscribe request for the client, see Err().

func (*Subscription) Err added in v0.0.3 

func (s *Subscription) Err() <-chan error

Err returns a channel that is closed when the client send an unsubscribe request.

func (*Subscription) MarshalJSON added in v0.0.3 

func (s *Subscription) MarshalJSON() ([]byte, error)

MarshalJSON marshals a subscription as its ID.

Source Files

View all Source files

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL
go.dev uses cookies from Google to deliver and enhance the quality of its services and to analyze traffic. Learn more.