2018-06-20 12:06:27 +00:00
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// Copyright 2018 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 swarm
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import (
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"context"
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"flag"
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"fmt"
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"io/ioutil"
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"math/rand"
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"os"
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"sync"
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"sync/atomic"
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"testing"
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"time"
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"github.com/ethereum/go-ethereum/crypto"
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"github.com/ethereum/go-ethereum/log"
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"github.com/ethereum/go-ethereum/node"
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"github.com/ethereum/go-ethereum/p2p/discover"
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"github.com/ethereum/go-ethereum/p2p/simulations/adapters"
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"github.com/ethereum/go-ethereum/swarm/api"
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"github.com/ethereum/go-ethereum/swarm/network"
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2018-07-17 05:08:34 +00:00
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"github.com/ethereum/go-ethereum/swarm/network/simulation"
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2018-06-20 12:06:27 +00:00
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"github.com/ethereum/go-ethereum/swarm/storage"
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colorable "github.com/mattn/go-colorable"
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)
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var (
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loglevel = flag.Int("loglevel", 2, "verbosity of logs")
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longrunning = flag.Bool("longrunning", false, "do run long-running tests")
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waitKademlia = flag.Bool("waitkademlia", false, "wait for healthy kademlia before checking files availability")
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)
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func init() {
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rand.Seed(time.Now().UnixNano())
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flag.Parse()
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log.Root().SetHandler(log.LvlFilterHandler(log.Lvl(*loglevel), log.StreamHandler(colorable.NewColorableStderr(), log.TerminalFormat(true))))
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}
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// TestSwarmNetwork runs a series of test simulations with
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// static and dynamic Swarm nodes in network simulation, by
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// uploading files to every node and retrieving them.
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func TestSwarmNetwork(t *testing.T) {
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for _, tc := range []struct {
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name string
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steps []testSwarmNetworkStep
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options *testSwarmNetworkOptions
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disabled bool
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}{
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{
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name: "10_nodes",
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steps: []testSwarmNetworkStep{
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{
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nodeCount: 10,
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},
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},
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options: &testSwarmNetworkOptions{
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Timeout: 45 * time.Second,
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},
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},
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{
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name: "10_nodes_skip_check",
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steps: []testSwarmNetworkStep{
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{
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nodeCount: 10,
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},
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},
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options: &testSwarmNetworkOptions{
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Timeout: 45 * time.Second,
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SkipCheck: true,
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},
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},
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{
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name: "100_nodes",
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steps: []testSwarmNetworkStep{
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{
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nodeCount: 100,
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},
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},
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options: &testSwarmNetworkOptions{
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Timeout: 3 * time.Minute,
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},
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disabled: !*longrunning,
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},
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{
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name: "100_nodes_skip_check",
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steps: []testSwarmNetworkStep{
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{
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nodeCount: 100,
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},
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},
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options: &testSwarmNetworkOptions{
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Timeout: 3 * time.Minute,
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SkipCheck: true,
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},
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disabled: !*longrunning,
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},
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{
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name: "inc_node_count",
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steps: []testSwarmNetworkStep{
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{
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nodeCount: 2,
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},
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{
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nodeCount: 5,
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},
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{
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nodeCount: 10,
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},
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},
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options: &testSwarmNetworkOptions{
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Timeout: 90 * time.Second,
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},
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disabled: !*longrunning,
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},
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{
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name: "dec_node_count",
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steps: []testSwarmNetworkStep{
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{
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nodeCount: 10,
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},
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{
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nodeCount: 6,
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},
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{
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nodeCount: 3,
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},
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},
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options: &testSwarmNetworkOptions{
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Timeout: 90 * time.Second,
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},
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disabled: !*longrunning,
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},
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{
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name: "dec_inc_node_count",
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steps: []testSwarmNetworkStep{
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{
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nodeCount: 5,
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},
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{
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nodeCount: 3,
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},
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{
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nodeCount: 10,
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},
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},
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options: &testSwarmNetworkOptions{
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Timeout: 90 * time.Second,
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},
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},
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{
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name: "inc_dec_node_count",
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steps: []testSwarmNetworkStep{
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{
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nodeCount: 3,
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},
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{
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nodeCount: 5,
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},
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{
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nodeCount: 25,
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},
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{
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nodeCount: 10,
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},
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{
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nodeCount: 4,
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},
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},
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options: &testSwarmNetworkOptions{
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Timeout: 5 * time.Minute,
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},
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disabled: !*longrunning,
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},
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{
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name: "inc_dec_node_count_skip_check",
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steps: []testSwarmNetworkStep{
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{
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nodeCount: 3,
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},
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{
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nodeCount: 5,
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},
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{
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nodeCount: 25,
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},
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{
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nodeCount: 10,
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},
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{
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nodeCount: 4,
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},
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},
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options: &testSwarmNetworkOptions{
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Timeout: 5 * time.Minute,
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SkipCheck: true,
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},
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disabled: !*longrunning,
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},
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} {
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if tc.disabled {
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continue
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}
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t.Run(tc.name, func(t *testing.T) {
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testSwarmNetwork(t, tc.options, tc.steps...)
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})
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}
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}
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// testSwarmNetworkStep is the configuration
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// for the state of the simulation network.
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type testSwarmNetworkStep struct {
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// number of swarm nodes that must be in the Up state
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nodeCount int
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}
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// file represents the file uploaded on a particular node.
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type file struct {
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addr storage.Address
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data string
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nodeID discover.NodeID
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}
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// check represents a reference to a file that is retrieved
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// from a particular node.
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type check struct {
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key string
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nodeID discover.NodeID
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}
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// testSwarmNetworkOptions contains optional parameters for running
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// testSwarmNetwork.
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type testSwarmNetworkOptions struct {
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Timeout time.Duration
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SkipCheck bool
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}
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// testSwarmNetwork is a helper function used for testing different
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// static and dynamic Swarm network simulations.
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// It is responsible for:
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// - Setting up a Swarm network simulation, and updates the number of nodes within the network on every step according to steps.
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// - Uploading a unique file to every node on every step.
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// - May wait for Kademlia on every node to be healthy.
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// - Checking if a file is retrievable from all nodes.
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func testSwarmNetwork(t *testing.T, o *testSwarmNetworkOptions, steps ...testSwarmNetworkStep) {
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if o == nil {
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o = new(testSwarmNetworkOptions)
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}
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2018-07-17 05:08:34 +00:00
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sim := simulation.New(map[string]simulation.ServiceFunc{
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"swarm": func(ctx *adapters.ServiceContext, bucket *sync.Map) (s node.Service, cleanup func(), err error) {
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config := api.NewConfig()
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2018-07-17 05:08:34 +00:00
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dir, err := ioutil.TempDir("", "swarm-network-test-node")
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if err != nil {
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return nil, nil, err
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}
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cleanup = func() {
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err := os.RemoveAll(dir)
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if err != nil {
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log.Error("cleaning up swarm temp dir", "err", err)
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}
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}
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config.Path = dir
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privkey, err := crypto.GenerateKey()
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if err != nil {
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return nil, cleanup, err
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}
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config.Init(privkey)
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config.DeliverySkipCheck = o.SkipCheck
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swarm, err := NewSwarm(config, nil)
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if err != nil {
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return nil, cleanup, err
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}
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bucket.Store(simulation.BucketKeyKademlia, swarm.bzz.Hive.Overlay.(*network.Kademlia))
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log.Info("new swarm", "bzzKey", config.BzzKey, "baseAddr", fmt.Sprintf("%x", swarm.bzz.BaseAddr()))
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return swarm, cleanup, nil
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},
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})
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defer sim.Close()
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ctx := context.Background()
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if o.Timeout > 0 {
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var cancel context.CancelFunc
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ctx, cancel = context.WithTimeout(ctx, o.Timeout)
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defer cancel()
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}
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files := make([]file, 0)
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for i, step := range steps {
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log.Debug("test sync step", "n", i+1, "nodes", step.nodeCount)
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change := step.nodeCount - len(sim.UpNodeIDs())
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if change > 0 {
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_, err := sim.AddNodesAndConnectChain(change)
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if err != nil {
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t.Fatal(err)
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}
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} else if change < 0 {
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_, err := sim.StopRandomNodes(-change)
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if err != nil {
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t.Fatal(err)
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}
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} else {
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t.Logf("step %v: no change in nodes", i)
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continue
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}
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var checkStatusM sync.Map
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var nodeStatusM sync.Map
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var totalFoundCount uint64
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2018-07-17 05:08:34 +00:00
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result := sim.Run(ctx, func(ctx context.Context, sim *simulation.Simulation) error {
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nodeIDs := sim.UpNodeIDs()
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shuffle(len(nodeIDs), func(i, j int) {
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nodeIDs[i], nodeIDs[j] = nodeIDs[j], nodeIDs[i]
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})
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for _, id := range nodeIDs {
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key, data, err := uploadFile(sim.Service("swarm", id).(*Swarm))
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if err != nil {
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return err
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}
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log.Trace("file uploaded", "node", id, "key", key.String())
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files = append(files, file{
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addr: key,
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data: data,
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nodeID: id,
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})
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}
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2018-07-17 05:08:34 +00:00
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if *waitKademlia {
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if _, err := sim.WaitTillHealthy(ctx, 2); err != nil {
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return err
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}
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}
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// File retrieval check is repeated until all uploaded files are retrieved from all nodes
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// or until the timeout is reached.
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for {
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if retrieve(sim, files, &checkStatusM, &nodeStatusM, &totalFoundCount) == 0 {
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return nil
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}
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}
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})
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if result.Error != nil {
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t.Fatal(result.Error)
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}
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log.Debug("done: test sync step", "n", i+1, "nodes", step.nodeCount)
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}
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}
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// uploadFile, uploads a short file to the swarm instance
|
|
|
|
// using the api.Put method.
|
|
|
|
func uploadFile(swarm *Swarm) (storage.Address, string, error) {
|
|
|
|
b := make([]byte, 8)
|
|
|
|
_, err := rand.Read(b)
|
|
|
|
if err != nil {
|
|
|
|
return nil, "", err
|
|
|
|
}
|
|
|
|
// File data is very short, but it is ensured that its
|
|
|
|
// uniqueness is very certain.
|
|
|
|
data := fmt.Sprintf("test content %s %x", time.Now().Round(0), b)
|
2018-07-09 12:11:49 +00:00
|
|
|
ctx := context.TODO()
|
|
|
|
k, wait, err := swarm.api.Put(ctx, data, "text/plain", false)
|
2018-06-20 12:06:27 +00:00
|
|
|
if err != nil {
|
|
|
|
return nil, "", err
|
|
|
|
}
|
|
|
|
if wait != nil {
|
2018-07-09 12:11:49 +00:00
|
|
|
err = wait(ctx)
|
2018-06-20 12:06:27 +00:00
|
|
|
}
|
2018-07-09 12:11:49 +00:00
|
|
|
return k, data, err
|
2018-06-20 12:06:27 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
// retrieve is the function that is used for checking the availability of
|
|
|
|
// uploaded files in testSwarmNetwork test helper function.
|
|
|
|
func retrieve(
|
2018-07-17 05:08:34 +00:00
|
|
|
sim *simulation.Simulation,
|
2018-06-20 12:06:27 +00:00
|
|
|
files []file,
|
|
|
|
checkStatusM *sync.Map,
|
|
|
|
nodeStatusM *sync.Map,
|
|
|
|
totalFoundCount *uint64,
|
|
|
|
) (missing uint64) {
|
|
|
|
shuffle(len(files), func(i, j int) {
|
|
|
|
files[i], files[j] = files[j], files[i]
|
|
|
|
})
|
|
|
|
|
|
|
|
var totalWg sync.WaitGroup
|
|
|
|
errc := make(chan error)
|
|
|
|
|
2018-07-17 05:08:34 +00:00
|
|
|
nodeIDs := sim.UpNodeIDs()
|
2018-06-20 12:06:27 +00:00
|
|
|
|
|
|
|
totalCheckCount := len(nodeIDs) * len(files)
|
|
|
|
|
|
|
|
for _, id := range nodeIDs {
|
|
|
|
if _, ok := nodeStatusM.Load(id); ok {
|
|
|
|
continue
|
|
|
|
}
|
|
|
|
start := time.Now()
|
|
|
|
var checkCount uint64
|
|
|
|
var foundCount uint64
|
|
|
|
|
|
|
|
totalWg.Add(1)
|
|
|
|
|
|
|
|
var wg sync.WaitGroup
|
|
|
|
|
2018-07-17 05:08:34 +00:00
|
|
|
swarm := sim.Service("swarm", id).(*Swarm)
|
2018-06-20 12:06:27 +00:00
|
|
|
for _, f := range files {
|
|
|
|
|
|
|
|
checkKey := check{
|
|
|
|
key: f.addr.String(),
|
|
|
|
nodeID: id,
|
|
|
|
}
|
|
|
|
if n, ok := checkStatusM.Load(checkKey); ok && n.(int) == 0 {
|
|
|
|
continue
|
|
|
|
}
|
|
|
|
|
|
|
|
checkCount++
|
|
|
|
wg.Add(1)
|
|
|
|
go func(f file, id discover.NodeID) {
|
|
|
|
defer wg.Done()
|
|
|
|
|
|
|
|
log.Debug("api get: check file", "node", id.String(), "key", f.addr.String(), "total files found", atomic.LoadUint64(totalFoundCount))
|
|
|
|
|
2018-07-09 12:11:49 +00:00
|
|
|
r, _, _, _, err := swarm.api.Get(context.TODO(), f.addr, "/")
|
2018-06-20 12:06:27 +00:00
|
|
|
if err != nil {
|
|
|
|
errc <- fmt.Errorf("api get: node %s, key %s, kademlia %s: %v", id, f.addr, swarm.bzz.Hive, err)
|
|
|
|
return
|
|
|
|
}
|
|
|
|
d, err := ioutil.ReadAll(r)
|
|
|
|
if err != nil {
|
|
|
|
errc <- fmt.Errorf("api get: read response: node %s, key %s: kademlia %s: %v", id, f.addr, swarm.bzz.Hive, err)
|
|
|
|
return
|
|
|
|
}
|
|
|
|
data := string(d)
|
|
|
|
if data != f.data {
|
|
|
|
errc <- fmt.Errorf("file contend missmatch: node %s, key %s, expected %q, got %q", id, f.addr, f.data, data)
|
|
|
|
return
|
|
|
|
}
|
|
|
|
checkStatusM.Store(checkKey, 0)
|
|
|
|
atomic.AddUint64(&foundCount, 1)
|
|
|
|
log.Info("api get: file found", "node", id.String(), "key", f.addr.String(), "content", data, "files found", atomic.LoadUint64(&foundCount))
|
|
|
|
}(f, id)
|
|
|
|
}
|
|
|
|
|
|
|
|
go func(id discover.NodeID) {
|
|
|
|
defer totalWg.Done()
|
|
|
|
wg.Wait()
|
|
|
|
|
|
|
|
atomic.AddUint64(totalFoundCount, foundCount)
|
|
|
|
|
|
|
|
if foundCount == checkCount {
|
|
|
|
log.Info("all files are found for node", "id", id.String(), "duration", time.Since(start))
|
|
|
|
nodeStatusM.Store(id, 0)
|
|
|
|
return
|
|
|
|
}
|
|
|
|
log.Debug("files missing for node", "id", id.String(), "check", checkCount, "found", foundCount)
|
|
|
|
}(id)
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
go func() {
|
|
|
|
totalWg.Wait()
|
|
|
|
close(errc)
|
|
|
|
}()
|
|
|
|
|
|
|
|
var errCount int
|
|
|
|
for err := range errc {
|
|
|
|
if err != nil {
|
|
|
|
errCount++
|
|
|
|
}
|
|
|
|
log.Warn(err.Error())
|
|
|
|
}
|
|
|
|
|
|
|
|
log.Info("check stats", "total check count", totalCheckCount, "total files found", atomic.LoadUint64(totalFoundCount), "total errors", errCount)
|
|
|
|
|
|
|
|
return uint64(totalCheckCount) - atomic.LoadUint64(totalFoundCount)
|
|
|
|
}
|
|
|
|
|
|
|
|
// Backported from stdlib https://golang.org/src/math/rand/rand.go?s=11175:11215#L333
|
|
|
|
//
|
|
|
|
// Replace with rand.Shuffle from go 1.10 when go 1.9 support is dropped.
|
|
|
|
//
|
|
|
|
// shuffle pseudo-randomizes the order of elements.
|
|
|
|
// n is the number of elements. Shuffle panics if n < 0.
|
|
|
|
// swap swaps the elements with indexes i and j.
|
|
|
|
func shuffle(n int, swap func(i, j int)) {
|
|
|
|
if n < 0 {
|
|
|
|
panic("invalid argument to Shuffle")
|
|
|
|
}
|
|
|
|
|
|
|
|
// Fisher-Yates shuffle: https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle
|
|
|
|
// Shuffle really ought not be called with n that doesn't fit in 32 bits.
|
|
|
|
// Not only will it take a very long time, but with 2³¹! possible permutations,
|
|
|
|
// there's no way that any PRNG can have a big enough internal state to
|
|
|
|
// generate even a minuscule percentage of the possible permutations.
|
|
|
|
// Nevertheless, the right API signature accepts an int n, so handle it as best we can.
|
|
|
|
i := n - 1
|
|
|
|
for ; i > 1<<31-1-1; i-- {
|
|
|
|
j := int(rand.Int63n(int64(i + 1)))
|
|
|
|
swap(i, j)
|
|
|
|
}
|
|
|
|
for ; i > 0; i-- {
|
|
|
|
j := int(rand.Int31n(int32(i + 1)))
|
|
|
|
swap(i, j)
|
|
|
|
}
|
|
|
|
}
|