115 lines
2.7 KiB
Go
115 lines
2.7 KiB
Go
/*
|
|
* lrpc allows for clients to call functions on a server remotely.
|
|
* Copyright (C) 2022 Arsen Musayelyan
|
|
*
|
|
* This program is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
package server
|
|
|
|
import (
|
|
"context"
|
|
"time"
|
|
|
|
"go.arsenm.dev/lrpc/codec"
|
|
|
|
"github.com/gofrs/uuid"
|
|
)
|
|
|
|
// Context is a connection context for RPC calls
|
|
type Context struct {
|
|
isChannel bool
|
|
channelID string
|
|
channel chan any
|
|
|
|
codec codec.Codec
|
|
|
|
doneCh chan struct{}
|
|
canceled bool
|
|
|
|
ctx context.Context
|
|
}
|
|
|
|
func newContext(ctx context.Context, codec codec.Codec) *Context {
|
|
out := &Context{
|
|
doneCh: make(chan struct{}),
|
|
codec: codec,
|
|
ctx: ctx,
|
|
}
|
|
if ctx == nil {
|
|
out.ctx = context.Background()
|
|
}
|
|
go func() {
|
|
<-out.ctx.Done()
|
|
out.cancel()
|
|
}()
|
|
return out
|
|
}
|
|
|
|
// MakeChannel changes the function it's called in into a
|
|
// channel function, and returns a channel which can be used
|
|
// to send information to the client.
|
|
//
|
|
// This will ovewrite any return value of the function with
|
|
// a channel ID.
|
|
func (ctx *Context) MakeChannel() (chan<- any, error) {
|
|
ctx.isChannel = true
|
|
chID, err := uuid.NewV4()
|
|
ctx.channelID = chID.String()
|
|
ctx.channel = make(chan any, 5)
|
|
return ctx.channel, err
|
|
}
|
|
|
|
// GetCodec returns a codec bound to the connection
|
|
// that called this function
|
|
func (ctx *Context) GetCodec() codec.Codec {
|
|
return ctx.codec
|
|
}
|
|
|
|
// Deadline always returns the current time and false
|
|
// as this context does not support deadlines
|
|
func (ctx *Context) Deadline() (time.Time, bool) {
|
|
return time.Now(), false
|
|
}
|
|
|
|
// Value always returns nil as this context stores no values
|
|
func (ctx *Context) Value(key any) any {
|
|
return ctx.ctx.Value(key)
|
|
}
|
|
|
|
// Err returns context.Canceled if the context was canceled,
|
|
// otherwise nil
|
|
func (ctx *Context) Err() error {
|
|
if ctx.canceled {
|
|
return context.Canceled
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// Done returns a channel that will be closed when
|
|
// the context is canceled, such as when ChannelDone
|
|
// is called by the client
|
|
func (ctx *Context) Done() <-chan struct{} {
|
|
return ctx.doneCh
|
|
}
|
|
|
|
// Cancel cancels the context
|
|
func (ctx *Context) cancel() {
|
|
if ctx.canceled {
|
|
return
|
|
}
|
|
ctx.canceled = true
|
|
close(ctx.doneCh)
|
|
}
|