This commit is contained in:
crusader 2018-04-03 17:58:26 +09:00
commit 8587e2e369
20 changed files with 1074 additions and 0 deletions

68
.gitignore vendored Normal file
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# Created by .ignore support plugin (hsz.mobi)
### JetBrains template
# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and Webstorm
# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
# User-specific stuff:
.idea/**/workspace.xml
.idea/**/tasks.xml
.idea/dictionaries
# Sensitive or high-churn files:
.idea/**/dataSources/
.idea/**/dataSources.ids
.idea/**/dataSources.xml
.idea/**/dataSources.local.xml
.idea/**/sqlDataSources.xml
.idea/**/dynamic.xml
.idea/**/uiDesigner.xml
# Gradle:
.idea/**/gradle.xml
.idea/**/libraries
# Mongo Explorer plugin:
.idea/**/mongoSettings.xml
## File-based project format:
*.iws
## Plugin-specific files:
# IntelliJ
/out/
# mpeltonen/sbt-idea plugin
.idea_modules/
# JIRA plugin
atlassian-ide-plugin.xml
# Crashlytics plugin (for Android Studio and IntelliJ)
com_crashlytics_export_strings.xml
crashlytics.properties
crashlytics-build.properties
fabric.properties
### Go template
# Binaries for programs and plugins
*.exe
*.dll
*.so
*.dylib
# Test binary, build with `go test -c`
*.test
# Output of the go coverage tool, specifically when used with LiteIDE
*.out
# Project-local glide cache, RE: https://github.com/Masterminds/glide/issues/736
.glide/
.idea/
*.iml
vendor/
glide.lock
.DS_Store
dist/
debug

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.vscode/launch.json vendored Normal file
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{
"version": "0.2.0",
"configurations": [
{
"name": "Debug",
"type": "go",
"request": "launch",
"mode": "debug",
"remotePath": "",
"port": 2345,
"host": "127.0.0.1",
"program": "${workspaceRoot}/main.go",
"env": {},
"args": [],
"showLog": true
},
{
"name": "File Debug",
"type": "go",
"request": "launch",
"mode": "debug",
"remotePath": "",
"port": 2345,
"host": "127.0.0.1",
"program": "${fileDirname}",
"env": {},
"args": [],
"showLog": true
}
]
}

6
glide.yaml Normal file
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package: git.loafle.net/commons/rpc-go
import:
- package: git.loafle.net/commons/util-go
subpackages:
- encoding/json
- reflect

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protocol/client_codec.go Normal file
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package protocol
// ClientCodec creates a ClientCodecRequest to process each request.
type ClientCodec interface {
NewRequest(method string, args []interface{}, id interface{}) ([]byte, error)
NewResponse(buf []byte) (ClientResponseCodec, error)
}
type ClientResponseCodec interface {
Notification() (ClientNotificationCodec, error)
Result(result interface{}) error
Error() *Error
ID() interface{}
}
type ClientNotificationCodec interface {
RegistryCodec
}

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protocol/error.go Normal file
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package protocol
import (
"errors"
"fmt"
)
type ErrorCode int
const (
E_PARSE ErrorCode = -32700
E_INVALID_REQ ErrorCode = -32600
E_NO_METHOD ErrorCode = -32601
E_BAD_PARAMS ErrorCode = -32602
E_INTERNAL ErrorCode = -32603
E_SERVER ErrorCode = -32000
)
var ErrNullResult = errors.New("result is null")
type Error struct {
// A Number that indicates the error type that occurred.
Code ErrorCode `json:"code"` /* required */
// A String providing a short description of the error.
// The message SHOULD be limited to a concise single sentence.
Message string `json:"message"` /* required */
// A Primitive or Structured value that contains additional information about the error.
Data interface{} `json:"data"` /* optional */
}
func (e Error) Error() string {
return fmt.Sprintf("Code[%d] Message[%s] Data[%v]", e.Code, e.Message, e.Data)
}

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protocol/json/client.go Normal file
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package json
import (
"encoding/json"
"git.loafle.net/commons/rpc-go/protocol"
)
// ----------------------------------------------------------------------------
// Codec
// ----------------------------------------------------------------------------
// NewClientCodec returns a new JSON Codec.
func NewClientCodec() protocol.ClientCodec {
return &ClientCodec{}
}
// ClientCodec creates a ClientCodecRequest to process each request.
type ClientCodec struct {
}
func (cc *ClientCodec) NewRequest(method string, args []interface{}, id interface{}) ([]byte, error) {
params, err := convertParamsToStringArray(args)
if nil != err {
return nil, err
}
req := &clientRequest{
Version: Version,
Method: method,
Params: params,
ID: id,
}
return json.Marshal(req)
}
func (cc *ClientCodec) NewResponse(buf []byte) (protocol.ClientResponseCodec, error) {
return newClientResponseCodec(buf)
}

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package json
import (
"encoding/json"
crp "git.loafle.net/commons/rpc-go/protocol"
cuej "git.loafle.net/commons/util-go/encoding/json"
)
// ----------------------------------------------------------------------------
// ClientNotificationCodec
// ----------------------------------------------------------------------------
// clientRequest represents a JSON-RPC notification sent to a client.
type clientNotification struct {
// A String containing the name of the method to be invoked.
Method string `json:"method"`
// Object to pass as request parameter to the method.
Params *json.RawMessage `json:"params,omitempty"`
}
// ClientNotificationCodec decodes and encodes a single notification.
type ClientNotificationCodec struct {
noti *clientNotification
err error
}
func (cnc *ClientNotificationCodec) HasResponse() bool {
return false
}
func (cnc *ClientNotificationCodec) Method() string {
return cnc.noti.Method
}
func (cnc *ClientNotificationCodec) ReadParams(args []interface{}) error {
if cnc.err == nil && cnc.noti.Params != nil {
// Note: if scr.request.Params is nil it's not an error, it's an optional member.
// JSON params structured object. Unmarshal to the args object.
if err := cuej.SetValueWithJSONStringArray(*cnc.noti.Params, args); nil != err {
cnc.err = &crp.Error{
Code: crp.E_INVALID_REQ,
Message: err.Error(),
Data: cnc.noti.Params,
}
return cnc.err
}
return nil
}
return cnc.err
}
func (cnc *ClientNotificationCodec) Params() ([]string, error) {
if cnc.err == nil && cnc.noti.Params != nil {
var values []string
if err := json.Unmarshal(*cnc.noti.Params, &values); err != nil {
cnc.err = &crp.Error{
Code: crp.E_INVALID_REQ,
Message: err.Error(),
Data: cnc.noti.Params,
}
return nil, cnc.err
}
return values, nil
}
return nil, cnc.err
}

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package json
// ----------------------------------------------------------------------------
// Request and Response
// ----------------------------------------------------------------------------
// clientRequest represents a JSON-RPC request sent by a client.
type clientRequest struct {
// JSON-RPC protocol.
Version string `json:"jsonrpc"`
// A String containing the name of the method to be invoked.
Method string `json:"method"`
// Object to pass as request parameter to the method.
Params interface{} `json:"params"`
// The request id. This can be of any type. It is used to match the
// response with the request that it is replying to.
ID interface{} `json:"id"`
}

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package json
import (
"encoding/json"
"fmt"
"git.loafle.net/commons/rpc-go/protocol"
)
// ----------------------------------------------------------------------------
// ClientResponseCodec
// ----------------------------------------------------------------------------
// clientResponse represents a JSON-RPC response returned to a client.
type clientResponse struct {
Version string `json:"jsonrpc"`
Result *json.RawMessage `json:"result,omitempty"`
Error *json.RawMessage `json:"error,omitempty"`
ID interface{} `json:"id,omitempty"`
}
// ClientResponseCodec decodes and encodes a single request.
type ClientResponseCodec struct {
res *clientResponse
err error
}
func (crc *ClientResponseCodec) ID() interface{} {
return crc.res.ID
}
func (crc *ClientResponseCodec) Result(result interface{}) error {
if nil == crc.err && nil != crc.res.Result {
if err := json.Unmarshal(*crc.res.Result, result); nil != err {
crc.err = &protocol.Error{
Code: protocol.E_PARSE,
Message: err.Error(),
Data: crc.res.Result,
}
}
}
return crc.err
}
func (crc *ClientResponseCodec) Error() *protocol.Error {
if nil == crc.res.Error {
return nil
}
protocolError := &protocol.Error{}
err := json.Unmarshal(*crc.res.Error, protocolError)
if nil != err {
return &protocol.Error{
Code: protocol.E_PARSE,
Message: err.Error(),
Data: crc.res.Error,
}
}
return protocolError
}
func (crc *ClientResponseCodec) Notification() (protocol.ClientNotificationCodec, error) {
if nil != crc.res.ID || nil == crc.res.Result {
return nil, fmt.Errorf("RPC[JSON]: This is not notification")
}
noti := &clientNotification{}
err := json.Unmarshal(*crc.res.Result, noti)
if nil != err {
return nil, err
}
return &ClientNotificationCodec{noti: noti, err: err}, nil
}
// newClientMessageCodec returns a new ClientMessageCodec.
func newClientResponseCodec(buf []byte) (protocol.ClientResponseCodec, error) {
res := &clientResponse{}
err := json.Unmarshal(buf, res)
if err != nil {
err = &protocol.Error{
Code: protocol.E_PARSE,
Message: err.Error(),
Data: res,
}
}
if res.Version != Version {
err = &protocol.Error{
Code: protocol.E_INVALID_REQ,
Message: "jsonrpc must be " + Version,
Data: res,
}
}
return &ClientResponseCodec{res: res, err: err}, nil
}

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package json
const (
Name = "jsonrpc"
Version = "2.0"
)

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protocol/json/server.go Normal file
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package json
import (
"encoding/json"
"git.loafle.net/commons/rpc-go/protocol"
)
var null = json.RawMessage([]byte("null"))
// ----------------------------------------------------------------------------
// Codec
// ----------------------------------------------------------------------------
// NewServerCodec returns a new JSON Codec.
func NewServerCodec() protocol.ServerCodec {
return &ServerCodec{}
}
// ServerCodec creates a ServerRequestCodec to process each request.
type ServerCodec struct {
}
func (sc *ServerCodec) NewRequest(buf []byte) (protocol.ServerRequestCodec, error) {
return newServerRequestCodec(buf)
}
func (sc *ServerCodec) NewNotification(method string, args []interface{}) ([]byte, error) {
params, err := convertParamsToStringArray(args)
if nil != err {
return nil, err
}
noti := &serverNotification{Method: method, Params: params}
res := &serverResponse{Version: Version, Result: noti}
return json.Marshal(res)
}

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package json
// clientRequest represents a JSON-RPC request sent by a client.
type serverNotification struct {
// A String containing the name of the method to be invoked.
Method string `json:"method"`
// Object to pass as request parameter to the method.
Params interface{} `json:"params"`
}

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package json
import (
"encoding/json"
"git.loafle.net/commons/rpc-go/protocol"
cuej "git.loafle.net/commons/util-go/encoding/json"
)
// ----------------------------------------------------------------------------
// Request
// ----------------------------------------------------------------------------
// serverRequest represents a JSON-RPC request received by the server.
type serverRequest struct {
// JSON-RPC protocol.
Version string `json:"jsonrpc"`
// A String containing the name of the method to be invoked.
Method string `json:"method"`
// A Structured value to pass as arguments to the method.
Params *json.RawMessage `json:"params,omitempty"`
// The request id. MUST be a string, number or null.
// Our implementation will not do type checking for id.
// It will be copied as it is.
ID *json.RawMessage `json:"id,omitempty"`
}
// ----------------------------------------------------------------------------
// ServerRequestCodec
// ----------------------------------------------------------------------------
// newRequestCodec returns a new ServerRequestCodec.
func newServerRequestCodec(buf []byte) (protocol.ServerRequestCodec, error) {
req := &serverRequest{}
err := json.Unmarshal(buf, req)
if err != nil {
err = &protocol.Error{
Code: protocol.E_PARSE,
Message: err.Error(),
Data: req,
}
}
if req.Version != Version {
err = &protocol.Error{
Code: protocol.E_INVALID_REQ,
Message: "jsonrpc must be " + Version,
Data: req,
}
}
return &ServerRequestCodec{req: req, err: err}, nil
}
// ServerRequestCodec decodes and encodes a single request.
type ServerRequestCodec struct {
req *serverRequest
err error
}
func (src *ServerRequestCodec) HasResponse() bool {
return src.req.ID != nil
}
// Method returns the RPC method for the current request.
//
// The method uses a dotted notation as in "Service.Method".
func (src *ServerRequestCodec) Method() string {
return src.req.Method
}
// ReadRequest fills the request object for the RPC method.
//
// ReadRequest parses request parameters in two supported forms in
// accordance with http://www.jsonrpc.org/specification#parameter_structures
//
// by-position: params MUST be an Array, containing the
// values in the Server expected order.
//
// by-name: params MUST be an Object, with member names
// that match the Server expected parameter names. The
// absence of expected names MAY result in an error being
// generated. The names MUST match exactly, including
// case, to the method's expected parameters.
func (src *ServerRequestCodec) ReadParams(args []interface{}) error {
if src.err == nil && src.req.Params != nil {
// Note: if scr.request.Params is nil it's not an error, it's an optional member.
// JSON params structured object. Unmarshal to the args object.
if err := cuej.SetValueWithJSONStringArray(*src.req.Params, args); nil != err {
src.err = &protocol.Error{
Code: protocol.E_INVALID_REQ,
Message: err.Error(),
Data: src.req.Params,
}
return src.err
}
return nil
}
return src.err
}
func (src *ServerRequestCodec) Params() ([]string, error) {
if src.err == nil && src.req.Params != nil {
var values []string
if err := json.Unmarshal(*src.req.Params, &values); err != nil {
src.err = &protocol.Error{
Code: protocol.E_INVALID_REQ,
Message: err.Error(),
Data: src.req.Params,
}
return nil, src.err
}
return values, nil
}
return nil, src.err
}
func (src *ServerRequestCodec) NewResponse(reply interface{}) ([]byte, error) {
res := &serverResponse{Version: Version, Result: reply, ID: src.req.ID}
return src.newServerResponse(res)
}
func (src *ServerRequestCodec) NewError(status int, err error) ([]byte, error) {
jsonErr, ok := err.(*protocol.Error)
if !ok {
jsonErr = &protocol.Error{
Code: protocol.E_SERVER,
Message: err.Error(),
}
}
res := &serverResponse{Version: Version, Error: jsonErr, ID: src.req.ID}
return src.newServerResponse(res)
}
func (src *ServerRequestCodec) newServerResponse(res *serverResponse) ([]byte, error) {
return json.Marshal(res)
}

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package json
import (
"encoding/json"
"git.loafle.net/commons/rpc-go/protocol"
)
// ----------------------------------------------------------------------------
// Response
// ----------------------------------------------------------------------------
// serverResponse represents a JSON-RPC response returned by the server.
type serverResponse struct {
// JSON-RPC protocol.
Version string `json:"jsonrpc"`
// The Object that was returned by the invoked method. This must be null
// in case there was an error invoking the method.
// As per spec the member will be omitted if there was an error.
Result interface{} `json:"result,omitempty"`
// An Error object if there was an error invoking the method. It must be
// null if there was no error.
// As per spec the member will be omitted if there was no error.
Error *protocol.Error `json:"error,omitempty"`
// This must be the same id as the request it is responding to.
ID *json.RawMessage `json:"id,omitempty"`
}

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protocol/json/util.go Normal file
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package json
import (
"encoding/json"
"fmt"
"reflect"
cur "git.loafle.net/commons/util-go/reflect"
)
func convertParamsToStringArray(params []interface{}) ([]string, error) {
var values []string
if nil == params || 0 == len(params) {
return values, nil
}
for i, param := range params {
t := reflect.TypeOf(param)
switch t.Kind() {
case reflect.String:
values = append(values, param.(string))
case reflect.Array, reflect.Slice, reflect.Map, reflect.Struct:
b, err := json.Marshal(param)
if nil != err {
return nil, err
}
values = append(values, string(b))
case reflect.Ptr:
if t.Elem().Kind() != reflect.Struct {
return nil, fmt.Errorf("Pointer of param[%d] is permitted only Struct type", i)
}
b, err := json.Marshal(param)
if nil != err {
return nil, err
}
values = append(values, string(b))
default:
s, err := cur.ConvertToString(param)
if nil != err {
return nil, fmt.Errorf("String conversion of param[%d] has been failed [%v]", i, err)
}
values = append(values, s)
}
}
return values, nil
}

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package protocol
// ----------------------------------------------------------------------------
// Codec
// ----------------------------------------------------------------------------
// RegistryCodec creates a RegistryCodecRequest to process each request.
type RegistryCodec interface {
// Reads the request and returns the RPC method name.
Method() string
// Reads the request filling the RPC method args.
ReadParams(args []interface{}) error
Params() ([]string, error)
HasResponse() bool
}

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protocol/server_codec.go Normal file
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package protocol
// ServerCodec creates a ServerRequestCodec to process each request.
type ServerCodec interface {
NewRequest(buf []byte) (ServerRequestCodec, error)
NewNotification(method string, args []interface{}) ([]byte, error)
}
// ServerRequestCodec decodes a request and encodes a response using a specific
// serialization scheme.
type ServerRequestCodec interface {
RegistryCodec
NewResponse(reply interface{}) ([]byte, error)
NewError(status int, err error) ([]byte, error)
}

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registry/registry.go Normal file
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package registry
import (
"git.loafle.net/commons/rpc-go/protocol"
)
type RPCInvoker interface {
HasMethod(method string) bool
Invoke(codec protocol.RegistryCodec) (result interface{}, err error)
}

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registry/rpc_registry.go Normal file
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package registry
import (
"reflect"
"git.loafle.net/commons/rpc-go/protocol"
)
// NewRPCRegistry returns a new RPC registry.
func NewRPCRegistry() RPCRegistry {
return &rpcRegistry{
services: new(serviceMap),
}
}
type RPCRegistry interface {
RPCInvoker
GetService(name string) interface{}
RegisterService(receiver interface{}, name string) error
}
// RPCRegistry serves registered RPC services using registered codecs.
type rpcRegistry struct {
services *serviceMap
}
// RegisterService adds a new service to the server.
//
// The name parameter is optional: if empty it will be inferred from
// the receiver type name.
//
// Methods from the receiver will be extracted if these rules are satisfied:
//
// - The receiver is exported (begins with an upper case letter) or local
// (defined in the package registering the service).
// - The method name is exported.
// - The method has two arguments: *args, *reply.
// - All two arguments are pointers.
// - The first and second arguments are exported or local.
// - The method has return type error.
//
// All other methods are ignored.
func (rr *rpcRegistry) RegisterService(receiver interface{}, name string) error {
return rr.services.register(receiver, name)
}
func (rr *rpcRegistry) GetService(name string) interface{} {
return rr.services.getService(name)
}
// HasMethod returns true if the given method is registered.
//
// The method uses a dotted notation as in "Service.Method".
func (rr *rpcRegistry) HasMethod(method string) bool {
if _, _, err := rr.services.get(method); err == nil {
return true
}
return false
}
// Invoke execute a method.
//
// Codecs are defined to process a given serialization scheme, e.g., JSON or
// XML. A codec is chosen based on the "Content-Type" header from the request,
// excluding the charset definition.
func (rr *rpcRegistry) Invoke(codec protocol.RegistryCodec) (result interface{}, err error) {
serviceSpec, methodSpec, errGet := rr.services.get(codec.Method())
if errGet != nil {
return nil, errGet
}
// Decode the args.
var in []reflect.Value
pValues, pInstances := methodSpec.getParamValues()
if nil != pInstances && 0 < len(pInstances) {
if errRead := codec.ReadParams(pInstances); errRead != nil {
return nil, errRead
}
pCount := len(pInstances)
in = make([]reflect.Value, pCount+1)
for indexI := 0; indexI < pCount; indexI++ {
if pValues[indexI].Type().Kind() == reflect.Ptr && pValues[indexI].Type().Elem().Kind() != reflect.Struct {
in[indexI+1] = reflect.Indirect(pValues[indexI])
} else {
in[indexI+1] = pValues[indexI]
}
}
} else {
in = make([]reflect.Value, 1)
}
in[0] = serviceSpec.rcvrV
// Call the service method.
returnValues := methodSpec.method.Func.Call(in)
if nil != methodSpec.returnType {
result = returnValues[0].Interface()
if nil != returnValues[1].Interface() {
err = returnValues[1].Interface().(error)
}
} else {
if nil != returnValues[0].Interface() {
err = returnValues[0].Interface().(error)
}
}
return
}
// func convertValues(values []interface{}, types []reflect.Type) []reflect.Value {
// c := len(values)
// vs := make([]reflect.Value, c)
// for indexI := 0; indexI < c; indexI++ {
// vs[indexI] = convertValue(&values[indexI], types[indexI])
// }
// return vs
// }
// func convertValue(v *interface{}, t reflect.Type) reflect.Value {
// switch t.Kind() {
// case reflect.Bool:
// return reflect.ValueOf(*v).Convert(t)
// case reflect.Float32, reflect.Float64:
// return reflect.ValueOf(*v).Convert(t)
// case reflect.Int, reflect.Int32, reflect.Int64:
// return reflect.ValueOf(*v).Convert(t)
// case reflect.Interface:
// // When we see an interface, we make our own thing
// return reflect.ValueOf(*v).Convert(t)
// case reflect.Map:
// return reflect.ValueOf(*v).M
// return d.decodeMap(name, node, result)
// case reflect.Ptr:
// return d.decodePtr(name, node, result)
// case reflect.Slice:
// return d.decodeSlice(name, node, result)
// case reflect.String:
// return d.decodeString(name, node, result)
// case reflect.Struct:
// return d.decodeStruct(name, node, result)
// default:
// return &parser.PosError{
// Pos: node.Pos(),
// Err: fmt.Errorf("%s: unknown kind to decode into: %s", name, k.Kind()),
// }
// }
// }

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registry/service_map.go Normal file
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package registry
import (
"fmt"
"reflect"
"strings"
"sync"
"unicode"
"unicode/utf8"
)
var (
// Precompute the reflect.Type of error and http.Request
typeOfError = reflect.TypeOf((*error)(nil)).Elem()
)
// ----------------------------------------------------------------------------
// service
// ----------------------------------------------------------------------------
type service struct {
name string // name of service
rcvrV reflect.Value // receiver of methods for the service
rcvrT reflect.Type // type of the receiver
methods map[string]*serviceMethod // registered methods
}
type serviceMethod struct {
method reflect.Method // receiver method
paramTypes []reflect.Type // type of the request argument
returnType reflect.Type // type of the response argument
}
func (sm *serviceMethod) getParamValues() (values []reflect.Value, instances []interface{}) {
if nil == sm.paramTypes || 0 == len(sm.paramTypes) {
return nil, nil
}
pCount := len(sm.paramTypes)
values = make([]reflect.Value, pCount)
instances = make([]interface{}, pCount)
for indexI := 0; indexI < pCount; indexI++ {
values[indexI] = getValue(sm.paramTypes[indexI])
instances[indexI] = values[indexI].Interface()
}
return
}
func getValue(t reflect.Type) reflect.Value {
rt := t
if rt.Kind() == reflect.Ptr {
rt = rt.Elem()
}
// rv := reflect.New(rt)
// if rt.Kind() != reflect.Struct {
// rv = reflect.Indirect(rv)
// }
// var rv reflect.Value
// switch rt.Kind() {
// case reflect.Slice:
// rv = reflect.New(reflect.SliceOf(rt.Elem()))
// default:
// rv = reflect.New(rt)
// }
return reflect.New(rt)
}
// ----------------------------------------------------------------------------
// serviceMap
// ----------------------------------------------------------------------------
// serviceMap is a registry for services.
type serviceMap struct {
mutex sync.RWMutex
services map[string]*service
}
func (sm *serviceMap) getService(name string) interface{} {
sm.mutex.RLock()
defer sm.mutex.RUnlock()
if sm.services == nil {
return nil
}
return sm.services[name]
}
// register adds a new service using reflection to extract its methods.
func (sm *serviceMap) register(rcvr interface{}, name string) error {
// Setup service.
s := &service{
name: name,
rcvrV: reflect.ValueOf(rcvr),
rcvrT: reflect.TypeOf(rcvr),
methods: make(map[string]*serviceMethod),
}
if name == "" {
s.name = reflect.Indirect(s.rcvrV).Type().Name()
if !isExported(s.name) {
return fmt.Errorf("rpc: type %q is not exported", s.name)
}
}
if s.name == "" {
return fmt.Errorf("rpc: no service name for type %q",
s.rcvrT.String())
}
var err error
// Setup methods.
Loop:
for i := 0; i < s.rcvrT.NumMethod(); i++ {
m := s.rcvrT.Method(i)
mt := m.Type
// Method must be exported.
if m.PkgPath != "" {
continue
}
var paramTypes []reflect.Type
var returnType reflect.Type
pCount := mt.NumIn() - 1
if 0 < pCount {
paramTypes = make([]reflect.Type, pCount)
for indexI := 0; indexI < pCount; indexI++ {
pt := mt.In(indexI + 1)
if err = validateType(mt.In(indexI + 1)); nil != err {
return err
}
paramTypes[indexI] = pt
}
}
switch mt.NumOut() {
case 1:
if t := mt.Out(0); t != typeOfError {
continue Loop
}
case 2:
if t := mt.Out(0); !isExportedOrBuiltin(t) {
continue Loop
}
if t := mt.Out(1); t != typeOfError {
continue Loop
}
rt := mt.Out(0)
if err = validateType(rt); nil != err {
return err
}
returnType = rt
default:
continue
}
s.methods[m.Name] = &serviceMethod{
method: m,
paramTypes: paramTypes,
returnType: returnType,
}
}
if len(s.methods) == 0 {
return fmt.Errorf("rpc: %q has no exported methods of suitable type", s.name)
}
// Add to the map.
sm.mutex.Lock()
defer sm.mutex.Unlock()
if sm.services == nil {
sm.services = make(map[string]*service)
} else if _, ok := sm.services[s.name]; ok {
return fmt.Errorf("rpc: service already defined: %q", s.name)
}
sm.services[s.name] = s
return nil
}
func validateType(t reflect.Type) error {
if t.Kind() == reflect.Struct {
return fmt.Errorf("Type is Struct. Pass by reference, i.e. *%s", t)
}
return nil
}
// get returns a registered service given a method name.
//
// The method name uses a dotted notation as in "Service.Method".
func (sm *serviceMap) get(method string) (*service, *serviceMethod, error) {
parts := strings.Split(method, ".")
if len(parts) != 2 {
err := fmt.Errorf("rpc: service/method request ill-formed: %q", method)
return nil, nil, err
}
sm.mutex.Lock()
service := sm.services[parts[0]]
sm.mutex.Unlock()
if service == nil {
err := fmt.Errorf("rpc: can't find service %q", method)
return nil, nil, err
}
serviceMethod := service.methods[parts[1]]
if serviceMethod == nil {
err := fmt.Errorf("rpc: can't find method %q", method)
return nil, nil, err
}
return service, serviceMethod, nil
}
// isExported returns true of a string is an exported (upper case) name.
func isExported(name string) bool {
rune, _ := utf8.DecodeRuneInString(name)
return unicode.IsUpper(rune)
}
// isExportedOrBuiltin returns true if a type is exported or a builtin.
func isExportedOrBuiltin(t reflect.Type) bool {
for t.Kind() == reflect.Ptr {
t = t.Elem()
}
// PkgPath will be non-empty even for an exported type,
// so we need to check the type name as well.
return isExported(t.Name()) || t.PkgPath() == ""
}