mirror of
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542b839ec7
This silences a go vet message about copying p2p.Server in package node.
534 lines
17 KiB
Go
534 lines
17 KiB
Go
// Copyright 2015 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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package p2p
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import (
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"encoding/binary"
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"net"
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"reflect"
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"testing"
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"time"
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"github.com/davecgh/go-spew/spew"
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"github.com/ethereum/go-ethereum/p2p/discover"
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)
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func init() {
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spew.Config.Indent = "\t"
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}
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type dialtest struct {
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init *dialstate // state before and after the test.
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rounds []round
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}
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type round struct {
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peers []*Peer // current peer set
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done []task // tasks that got done this round
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new []task // the result must match this one
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}
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func runDialTest(t *testing.T, test dialtest) {
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var (
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vtime time.Time
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running int
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)
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pm := func(ps []*Peer) map[discover.NodeID]*Peer {
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m := make(map[discover.NodeID]*Peer)
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for _, p := range ps {
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m[p.rw.id] = p
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}
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return m
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}
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for i, round := range test.rounds {
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for _, task := range round.done {
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running--
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if running < 0 {
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panic("running task counter underflow")
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}
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test.init.taskDone(task, vtime)
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}
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new := test.init.newTasks(running, pm(round.peers), vtime)
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if !sametasks(new, round.new) {
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t.Errorf("round %d: new tasks mismatch:\ngot %v\nwant %v\nstate: %v\nrunning: %v\n",
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i, spew.Sdump(new), spew.Sdump(round.new), spew.Sdump(test.init), spew.Sdump(running))
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}
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// Time advances by 16 seconds on every round.
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vtime = vtime.Add(16 * time.Second)
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running += len(new)
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}
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}
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type fakeTable []*discover.Node
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func (t fakeTable) Self() *discover.Node { return new(discover.Node) }
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func (t fakeTable) Close() {}
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func (t fakeTable) Lookup(discover.NodeID) []*discover.Node { return nil }
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func (t fakeTable) Resolve(discover.NodeID) *discover.Node { return nil }
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func (t fakeTable) ReadRandomNodes(buf []*discover.Node) int { return copy(buf, t) }
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// This test checks that dynamic dials are launched from discovery results.
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func TestDialStateDynDial(t *testing.T) {
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runDialTest(t, dialtest{
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init: newDialState(nil, fakeTable{}, 5),
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rounds: []round{
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// A discovery query is launched.
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{
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peers: []*Peer{
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{rw: &conn{flags: staticDialedConn, id: uintID(0)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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},
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new: []task{&discoverTask{}},
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},
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// Dynamic dials are launched when it completes.
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{
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peers: []*Peer{
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{rw: &conn{flags: staticDialedConn, id: uintID(0)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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},
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done: []task{
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&discoverTask{results: []*discover.Node{
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{ID: uintID(2)}, // this one is already connected and not dialed.
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{ID: uintID(3)},
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{ID: uintID(4)},
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{ID: uintID(5)},
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{ID: uintID(6)}, // these are not tried because max dyn dials is 5
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{ID: uintID(7)}, // ...
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}},
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},
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new: []task{
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(3)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(4)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(5)}},
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},
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},
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// Some of the dials complete but no new ones are launched yet because
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// the sum of active dial count and dynamic peer count is == maxDynDials.
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{
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peers: []*Peer{
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{rw: &conn{flags: staticDialedConn, id: uintID(0)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(3)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(4)}},
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},
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done: []task{
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(3)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(4)}},
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},
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},
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// No new dial tasks are launched in the this round because
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// maxDynDials has been reached.
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{
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peers: []*Peer{
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{rw: &conn{flags: staticDialedConn, id: uintID(0)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(3)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(4)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(5)}},
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},
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done: []task{
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(5)}},
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},
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new: []task{
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&waitExpireTask{Duration: 14 * time.Second},
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},
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},
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// In this round, the peer with id 2 drops off. The query
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// results from last discovery lookup are reused.
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{
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peers: []*Peer{
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{rw: &conn{flags: staticDialedConn, id: uintID(0)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(3)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(4)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(5)}},
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},
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new: []task{
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(6)}},
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},
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},
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// More peers (3,4) drop off and dial for ID 6 completes.
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// The last query result from the discovery lookup is reused
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// and a new one is spawned because more candidates are needed.
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{
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peers: []*Peer{
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{rw: &conn{flags: staticDialedConn, id: uintID(0)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(5)}},
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},
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done: []task{
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(6)}},
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},
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new: []task{
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(7)}},
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&discoverTask{},
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},
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},
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// Peer 7 is connected, but there still aren't enough dynamic peers
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// (4 out of 5). However, a discovery is already running, so ensure
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// no new is started.
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{
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peers: []*Peer{
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{rw: &conn{flags: staticDialedConn, id: uintID(0)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(5)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(7)}},
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},
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done: []task{
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(7)}},
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},
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},
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// Finish the running node discovery with an empty set. A new lookup
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// should be immediately requested.
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{
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peers: []*Peer{
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{rw: &conn{flags: staticDialedConn, id: uintID(0)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(5)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(7)}},
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},
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done: []task{
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&discoverTask{},
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},
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new: []task{
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&discoverTask{},
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},
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},
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},
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})
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}
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func TestDialStateDynDialFromTable(t *testing.T) {
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// This table always returns the same random nodes
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// in the order given below.
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table := fakeTable{
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{ID: uintID(1)},
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{ID: uintID(2)},
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{ID: uintID(3)},
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{ID: uintID(4)},
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{ID: uintID(5)},
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{ID: uintID(6)},
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{ID: uintID(7)},
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{ID: uintID(8)},
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}
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runDialTest(t, dialtest{
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init: newDialState(nil, table, 10),
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rounds: []round{
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// 5 out of 8 of the nodes returned by ReadRandomNodes are dialed.
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{
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new: []task{
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(1)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(2)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(3)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(4)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(5)}},
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&discoverTask{},
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},
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},
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// Dialing nodes 1,2 succeeds. Dials from the lookup are launched.
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{
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peers: []*Peer{
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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},
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done: []task{
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(1)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(2)}},
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&discoverTask{results: []*discover.Node{
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{ID: uintID(10)},
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{ID: uintID(11)},
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{ID: uintID(12)},
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}},
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},
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new: []task{
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(10)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(11)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(12)}},
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&discoverTask{},
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},
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},
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// Dialing nodes 3,4,5 fails. The dials from the lookup succeed.
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{
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peers: []*Peer{
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(10)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(11)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(12)}},
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},
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done: []task{
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(3)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(4)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(5)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(10)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(11)}},
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&dialTask{flags: dynDialedConn, dest: &discover.Node{ID: uintID(12)}},
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},
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},
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// Waiting for expiry. No waitExpireTask is launched because the
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// discovery query is still running.
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{
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peers: []*Peer{
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(10)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(11)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(12)}},
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},
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},
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// Nodes 3,4 are not tried again because only the first two
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// returned random nodes (nodes 1,2) are tried and they're
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// already connected.
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{
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peers: []*Peer{
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(10)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(11)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(12)}},
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},
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},
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},
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})
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}
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// This test checks that static dials are launched.
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func TestDialStateStaticDial(t *testing.T) {
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wantStatic := []*discover.Node{
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{ID: uintID(1)},
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{ID: uintID(2)},
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{ID: uintID(3)},
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{ID: uintID(4)},
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{ID: uintID(5)},
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}
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runDialTest(t, dialtest{
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init: newDialState(wantStatic, fakeTable{}, 0),
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rounds: []round{
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// Static dials are launched for the nodes that
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// aren't yet connected.
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{
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peers: []*Peer{
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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},
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new: []task{
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(3)}},
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(4)}},
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(5)}},
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},
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},
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// No new tasks are launched in this round because all static
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// nodes are either connected or still being dialed.
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{
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peers: []*Peer{
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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{rw: &conn{flags: staticDialedConn, id: uintID(3)}},
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},
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done: []task{
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(3)}},
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},
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},
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// No new dial tasks are launched because all static
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// nodes are now connected.
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{
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peers: []*Peer{
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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{rw: &conn{flags: staticDialedConn, id: uintID(3)}},
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{rw: &conn{flags: staticDialedConn, id: uintID(4)}},
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{rw: &conn{flags: staticDialedConn, id: uintID(5)}},
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},
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done: []task{
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(4)}},
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(5)}},
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},
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new: []task{
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&waitExpireTask{Duration: 14 * time.Second},
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},
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},
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// Wait a round for dial history to expire, no new tasks should spawn.
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{
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peers: []*Peer{
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
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{rw: &conn{flags: staticDialedConn, id: uintID(3)}},
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{rw: &conn{flags: staticDialedConn, id: uintID(4)}},
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{rw: &conn{flags: staticDialedConn, id: uintID(5)}},
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},
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},
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// If a static node is dropped, it should be immediately redialed,
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// irrespective whether it was originally static or dynamic.
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{
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peers: []*Peer{
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{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
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{rw: &conn{flags: staticDialedConn, id: uintID(3)}},
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{rw: &conn{flags: staticDialedConn, id: uintID(5)}},
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},
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new: []task{
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(2)}},
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(4)}},
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},
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},
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},
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})
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}
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// This test checks that past dials are not retried for some time.
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func TestDialStateCache(t *testing.T) {
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wantStatic := []*discover.Node{
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{ID: uintID(1)},
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{ID: uintID(2)},
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{ID: uintID(3)},
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}
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runDialTest(t, dialtest{
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init: newDialState(wantStatic, fakeTable{}, 0),
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rounds: []round{
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// Static dials are launched for the nodes that
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// aren't yet connected.
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{
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peers: nil,
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new: []task{
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(1)}},
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(2)}},
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(3)}},
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},
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},
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// No new tasks are launched in this round because all static
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// nodes are either connected or still being dialed.
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{
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peers: []*Peer{
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{rw: &conn{flags: staticDialedConn, id: uintID(1)}},
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{rw: &conn{flags: staticDialedConn, id: uintID(2)}},
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},
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done: []task{
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(1)}},
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&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(2)}},
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},
|
|
},
|
|
// A salvage task is launched to wait for node 3's history
|
|
// entry to expire.
|
|
{
|
|
peers: []*Peer{
|
|
{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
|
|
{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
|
|
},
|
|
done: []task{
|
|
&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(3)}},
|
|
},
|
|
new: []task{
|
|
&waitExpireTask{Duration: 14 * time.Second},
|
|
},
|
|
},
|
|
// Still waiting for node 3's entry to expire in the cache.
|
|
{
|
|
peers: []*Peer{
|
|
{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
|
|
{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
|
|
},
|
|
},
|
|
// The cache entry for node 3 has expired and is retried.
|
|
{
|
|
peers: []*Peer{
|
|
{rw: &conn{flags: dynDialedConn, id: uintID(1)}},
|
|
{rw: &conn{flags: dynDialedConn, id: uintID(2)}},
|
|
},
|
|
new: []task{
|
|
&dialTask{flags: staticDialedConn, dest: &discover.Node{ID: uintID(3)}},
|
|
},
|
|
},
|
|
},
|
|
})
|
|
}
|
|
|
|
func TestDialResolve(t *testing.T) {
|
|
resolved := discover.NewNode(uintID(1), net.IP{127, 0, 55, 234}, 3333, 4444)
|
|
table := &resolveMock{answer: resolved}
|
|
state := newDialState(nil, table, 0)
|
|
|
|
// Check that the task is generated with an incomplete ID.
|
|
dest := discover.NewNode(uintID(1), nil, 0, 0)
|
|
state.addStatic(dest)
|
|
tasks := state.newTasks(0, nil, time.Time{})
|
|
if !reflect.DeepEqual(tasks, []task{&dialTask{flags: staticDialedConn, dest: dest}}) {
|
|
t.Fatalf("expected dial task, got %#v", tasks)
|
|
}
|
|
|
|
// Now run the task, it should resolve the ID once.
|
|
config := Config{Dialer: &net.Dialer{Deadline: time.Now().Add(-5 * time.Minute)}}
|
|
srv := &Server{ntab: table, Config: config}
|
|
tasks[0].Do(srv)
|
|
if !reflect.DeepEqual(table.resolveCalls, []discover.NodeID{dest.ID}) {
|
|
t.Fatalf("wrong resolve calls, got %v", table.resolveCalls)
|
|
}
|
|
|
|
// Report it as done to the dialer, which should update the static node record.
|
|
state.taskDone(tasks[0], time.Now())
|
|
if state.static[uintID(1)].dest != resolved {
|
|
t.Fatalf("state.dest not updated")
|
|
}
|
|
}
|
|
|
|
// compares task lists but doesn't care about the order.
|
|
func sametasks(a, b []task) bool {
|
|
if len(a) != len(b) {
|
|
return false
|
|
}
|
|
next:
|
|
for _, ta := range a {
|
|
for _, tb := range b {
|
|
if reflect.DeepEqual(ta, tb) {
|
|
continue next
|
|
}
|
|
}
|
|
return false
|
|
}
|
|
return true
|
|
}
|
|
|
|
func uintID(i uint32) discover.NodeID {
|
|
var id discover.NodeID
|
|
binary.BigEndian.PutUint32(id[:], i)
|
|
return id
|
|
}
|
|
|
|
// implements discoverTable for TestDialResolve
|
|
type resolveMock struct {
|
|
resolveCalls []discover.NodeID
|
|
answer *discover.Node
|
|
}
|
|
|
|
func (t *resolveMock) Resolve(id discover.NodeID) *discover.Node {
|
|
t.resolveCalls = append(t.resolveCalls, id)
|
|
return t.answer
|
|
}
|
|
|
|
func (t *resolveMock) Self() *discover.Node { return new(discover.Node) }
|
|
func (t *resolveMock) Close() {}
|
|
func (t *resolveMock) Bootstrap([]*discover.Node) {}
|
|
func (t *resolveMock) Lookup(discover.NodeID) []*discover.Node { return nil }
|
|
func (t *resolveMock) ReadRandomNodes(buf []*discover.Node) int { return 0 }
|