66 lines
1.6 KiB
Go
66 lines
1.6 KiB
Go
// Copyright (C) 2019 Storj Labs, Inc.
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// See LICENSE for copying information.
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package rpc
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import (
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"net"
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"time"
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"github.com/zeebo/errs"
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"gopkg.in/spacemonkeygo/monkit.v2"
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"storj.io/storj/private/memory"
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)
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//go:generate go run gen.go ../pb drpc compat_drpc.go
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//go:generate go run gen.go ../pb grpc compat_grpc.go
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var mon = monkit.Package()
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// Error wraps all of the errors returned by this package.
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var Error = errs.Class("rpccompat")
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// timedConn wraps a net.Conn so that all reads and writes get the specified timeout and
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// return bytes no faster than the rate. If the timeout or rate are zero, they are
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// ignored.
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type timedConn struct {
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net.Conn
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rate memory.Size
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}
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// now returns time.Now if there's a nonzero rate.
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func (t *timedConn) now() (now time.Time) {
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if t.rate > 0 {
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now = time.Now()
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}
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return now
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}
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// delay ensures that we sleep to keep the rate if it is nonzero. n is the number of
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// bytes in the read or write operation we need to delay.
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func (t *timedConn) delay(start time.Time, n int) {
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if t.rate > 0 {
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expected := time.Duration(n * int(time.Second) / t.rate.Int())
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if actual := time.Since(start); expected > actual {
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time.Sleep(expected - actual)
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}
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}
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}
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// Read wraps the connection read and adds sleeping to ensure the rate.
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func (t *timedConn) Read(p []byte) (int, error) {
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start := t.now()
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n, err := t.Conn.Read(p)
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t.delay(start, n)
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return n, err
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}
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// Write wraps the connection write and adds sleeping to ensure the rate.
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func (t *timedConn) Write(p []byte) (int, error) {
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start := t.now()
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n, err := t.Conn.Write(p)
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t.delay(start, n)
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return n, err
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}
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