path: root/swarm/network/stream/snapshot_retrieval_test.go

// Copyright 2018 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package stream

import (
    "context"
    crand "crypto/rand"
    "fmt"
    "math/rand"
    "strings"
    "sync"
    "testing"
    "time"

    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/p2p/discover"
    "github.com/ethereum/go-ethereum/p2p/simulations"
    "github.com/ethereum/go-ethereum/swarm/log"
    "github.com/ethereum/go-ethereum/swarm/network"
    streamTesting "github.com/ethereum/go-ethereum/swarm/network/stream/testing"
    "github.com/ethereum/go-ethereum/swarm/storage"
)

//constants for random file generation
const (
    minFileSize = 2
    maxFileSize = 40
)

func initRetrievalTest() {
    //global func to get overlay address from discover ID
    toAddr = func(id discover.NodeID) *network.BzzAddr {
        addr := network.NewAddrFromNodeID(id)
        return addr
    }
    //global func to create local store
    createStoreFunc = createTestLocalStorageForId
    //local stores
    stores = make(map[discover.NodeID]storage.ChunkStore)
    //data directories for each node and store
    datadirs = make(map[discover.NodeID]string)
    //deliveries for each node
    deliveries = make(map[discover.NodeID]*Delivery)
    //global retrieve func
    getRetrieveFunc = func(id discover.NodeID) func(chunk *storage.Chunk) error {
        return func(chunk *storage.Chunk) error {
            skipCheck := true
            return deliveries[id].RequestFromPeers(chunk.Addr[:], skipCheck)
        }
    }
    //registries, map of discover.NodeID to its streamer
    registries = make(map[discover.NodeID]*TestRegistry)
    //not needed for this test but required from common_test for NewStreamService
    waitPeerErrC = make(chan error)
    //also not needed for this test but required for NewStreamService
    peerCount = func(id discover.NodeID) int {
        if ids[0] == id || ids[len(ids)-1] == id {
            return 1
        }
        return 2
    }
}

//This test is a retrieval test for nodes.
//A configurable number of nodes can be
//provided to the test.
//Files are uploaded to nodes, other nodes try to retrieve the file
//Number of nodes can be provided via commandline too.
func TestFileRetrieval(t *testing.T) {
    if *nodes != 0 {
        fileRetrievalTest(t, *nodes)
    } else {
        nodeCnt := []int{16}
        //if the `longrunning` flag has been provided
        //run more test combinations
        if *longrunning {
            nodeCnt = append(nodeCnt, 32, 64, 128)
        }
        for _, n := range nodeCnt {
            fileRetrievalTest(t, n)
        }
    }
}

//This test is a retrieval test for nodes.
//One node is randomly selected to be the pivot node.
//A configurable number of chunks and nodes can be
//provided to the test, the number of chunks is uploaded
//to the pivot node and other nodes try to retrieve the chunk(s).
//Number of chunks and nodes can be provided via commandline too.
func TestRetrieval(t *testing.T) {
    //if nodes/chunks have been provided via commandline,
    //run the tests with these values
    if *nodes != 0 && *chunks != 0 {
        retrievalTest(t, *chunks, *nodes)
    } else {
        var nodeCnt []int
        var chnkCnt []int
        //if the `longrunning` flag has been provided
        //run more test combinations
        if *longrunning {
            nodeCnt = []int{16, 32, 128}
            chnkCnt = []int{4, 32, 256}
        } else {
            //default test
            nodeCnt = []int{16}
            chnkCnt = []int{32}
        }
        for _, n := range nodeCnt {
            for _, c := range chnkCnt {
                retrievalTest(t, c, n)
            }
        }
    }
}

//Every test runs 3 times, a live, a history, and a live AND history
func fileRetrievalTest(t *testing.T, nodeCount int) {
    //test live and NO history
    log.Info("Testing live and no history", "nodeCount", nodeCount)
    live = true
    history = false
    err := runFileRetrievalTest(nodeCount)
    if err != nil {
        t.Fatal(err)
    }
    //test history only
    log.Info("Testing history only", "nodeCount", nodeCount)
    live = false
    history = true
    err = runFileRetrievalTest(nodeCount)
    if err != nil {
        t.Fatal(err)
    }
    //finally test live and history
    log.Info("Testing live and history", "nodeCount", nodeCount)
    live = true
    err = runFileRetrievalTest(nodeCount)
    if err != nil {
        t.Fatal(err)
    }
}

//Every test runs 3 times, a live, a history, and a live AND history
func retrievalTest(t *testing.T, chunkCount int, nodeCount int) {
    //test live and NO history
    log.Info("Testing live and no history", "chunkCount", chunkCount, "nodeCount", nodeCount)
    live = true
    history = false
    err := runRetrievalTest(chunkCount, nodeCount)
    if err != nil {
        t.Fatal(err)
    }
    //test history only
    log.Info("Testing history only", "chunkCount", chunkCount, "nodeCount", nodeCount)
    live = false
    history = true
    err = runRetrievalTest(chunkCount, nodeCount)
    if err != nil {
        t.Fatal(err)
    }
    //finally test live and history
    log.Info("Testing live and history", "chunkCount", chunkCount, "nodeCount", nodeCount)
    live = true
    err = runRetrievalTest(chunkCount, nodeCount)
    if err != nil {
        t.Fatal(err)
    }
}

/*

The upload is done by dependency to the global
`live` and `history` variables;

If `live` is set, first stream subscriptions are established,
then files are uploaded to nodes.

If `history` is enabled, first upload files, then build up subscriptions.

The test loads a snapshot file to construct the swarm network,
assuming that the snapshot file identifies a healthy
kademlia network. Nevertheless a health check runs in the
simulation's `action` function.

The snapshot should have 'streamer' in its service list.
*/
func runFileRetrievalTest(nodeCount int) error {
    //for every run (live, history), int the variables
    initRetrievalTest()
    //the ids of the snapshot nodes, initiate only now as we need nodeCount
    ids = make([]discover.NodeID, nodeCount)
    //channel to check for disconnection errors
    disconnectC := make(chan error)
    //channel to close disconnection watcher routine
    quitC := make(chan struct{})
    //the test conf (using same as in `snapshot_sync_test`
    conf = &synctestConfig{}
    //map of overlay address to discover ID
    conf.addrToIdMap = make(map[string]discover.NodeID)
    //array where the generated chunk hashes will be stored
    conf.hashes = make([]storage.Address, 0)
    //load nodes from the snapshot file
    net, err := initNetWithSnapshot(nodeCount)
    if err != nil {
        return err
    }
    var rpcSubscriptionsWg sync.WaitGroup
    //do cleanup after test is terminated
    defer func() {
        //shutdown the snapshot network
        net.Shutdown()
        //after the test, clean up local stores initialized with createLocalStoreForId
        localStoreCleanup()
        //finally clear all data directories
        datadirsCleanup()
    }()
    //get the nodes of the network
    nodes := net.GetNodes()
    //iterate over all nodes...
    for c := 0; c < len(nodes); c++ {
        //create an array of discovery nodeIDS
        ids[c] = nodes[c].ID()
        a := network.ToOverlayAddr(ids[c].Bytes())
        //append it to the array of all overlay addresses
        conf.addrs = append(conf.addrs, a)
        conf.addrToIdMap[string(a)] = ids[c]
    }

    //needed for healthy call
    ppmap = network.NewPeerPotMap(testMinProxBinSize, conf.addrs)

    //an array for the random files
    var randomFiles []string
    //channel to signal when the upload has finished
    uploadFinished := make(chan struct{})
    //channel to trigger new node checks
    trigger := make(chan discover.NodeID)
    //simulation action
    action := func(ctx context.Context) error {
        //first run the health check on all nodes,
        //wait until nodes are all healthy
        ticker := time.NewTicker(200 * time.Millisecond)
        defer ticker.Stop()
        for range ticker.C {
            healthy := true
            for _, id := range ids {
                r := registries[id]
                //PeerPot for this node
                addr := common.Bytes2Hex(r.addr.OAddr)
                pp := ppmap[addr]
                //call Healthy RPC
                h := r.delivery.overlay.Healthy(pp)
                //print info
                log.Debug(r.delivery.overlay.String())
                log.Debug(fmt.Sprintf("IS HEALTHY: %t", h.GotNN && h.KnowNN && h.Full))
                if !h.GotNN || !h.Full {
                    healthy = false
                    break
                }
            }
            if healthy {
                break
            }
        }

        if history {
            log.Info("Uploading for history")
            //If testing only history, we upload the chunk(s) first
            conf.hashes, randomFiles, err = uploadFilesToNodes(nodes)
            if err != nil {
                return err
            }
        }

        //variables needed to wait for all subscriptions established before uploading
        errc := make(chan error)

        //now setup and start event watching in order to know when we can upload
        ctx, watchCancel := context.WithTimeout(context.Background(), MaxTimeout*time.Second)
        defer watchCancel()

        log.Info("Setting up stream subscription")
        //We need two iterations, one to subscribe to the subscription events
        //(so we know when setup phase is finished), and one to
        //actually run the stream subscriptions. We can't do it in the same iteration,
        //because while the first nodes in the loop are setting up subscriptions,
        //the latter ones have not subscribed to listen to peer events yet,
        //and then we miss events.

        //first iteration: setup disconnection watcher and subscribe to peer events
        for j, id := range ids {
            log.Trace(fmt.Sprintf("Subscribe to subscription events: %d", j))
            client, err := net.GetNode(id).Client()
            if err != nil {
                return err
            }
            wsDoneC := watchSubscriptionEvents(ctx, id, client, errc, quitC)
            // doneC is nil, the error happened which is sent to errc channel, already
            if wsDoneC == nil {
                continue
            }
            rpcSubscriptionsWg.Add(1)
            go func() {
                <-wsDoneC
                rpcSubscriptionsWg.Done()
            }()

            //watch for peers disconnecting
            wdDoneC, err := streamTesting.WatchDisconnections(id, client, disconnectC, quitC)
            if err != nil {
                return err
            }
            rpcSubscriptionsWg.Add(1)
            go func() {
                <-wdDoneC
                rpcSubscriptionsWg.Done()
            }()
        }

        //second iteration: start syncing and setup stream subscriptions
        for j, id := range ids {
            log.Trace(fmt.Sprintf("Start syncing and stream subscriptions: %d", j))
            client, err := net.GetNode(id).Client()
            if err != nil {
                return err
            }
            //start syncing!
            var cnt int
            err = client.CallContext(ctx, &cnt, "stream_startSyncing")
            if err != nil {
                return err
            }
            //increment the number of subscriptions we need to wait for
            //by the count returned from startSyncing (SYNC subscriptions)
            subscriptionCount += cnt
            //now also add the number of RETRIEVAL_REQUEST subscriptions
            for snid := range registries[id].peers {
                subscriptionCount++
                err = client.CallContext(ctx, nil, "stream_subscribeStream", snid, NewStream(swarmChunkServerStreamName, "", false), nil, Top)
                if err != nil {
                    return err
                }
            }
        }

        //now wait until the number of expected subscriptions has been finished
        //`watchSubscriptionEvents` will write with a `nil` value to errc
        //every time a `SubscriptionMsg` has been received
        for err := range errc {
            if err != nil {
                return err
            }
            //`nil` received, decrement count
            subscriptionCount--
            //all subscriptions received
            if subscriptionCount == 0 {
                break
            }
        }

        log.Info("Stream subscriptions successfully requested, action terminated")

        if live {
            //upload generated files to nodes
            var hashes []storage.Address
            var rfiles []string
            hashes, rfiles, err = uploadFilesToNodes(nodes)
            if err != nil {
                return err
            }
            conf.hashes = append(conf.hashes, hashes...)
            randomFiles = append(randomFiles, rfiles...)
            //signal to the trigger loop that the upload has finished
            uploadFinished <- struct{}{}
        }

        return nil
    }

    //check defines what will be checked during the test
    check := func(ctx context.Context, id discover.NodeID) (bool, error) {

        select {
        case <-ctx.Done():
            return false, ctx.Err()
        case e := <-disconnectC:
            log.Error(e.Error())
            return false, fmt.Errorf("Disconnect event detected, network unhealthy")
        default:
        }
        log.Trace(fmt.Sprintf("Checking node: %s", id))
        //if there are more than one chunk, test only succeeds if all expected chunks are found
        allSuccess := true

        //check on the node's FileStore (netstore)
        fileStore := registries[id].fileStore
        //check all chunks
        for i, hash := range conf.hashes {
            reader, _ := fileStore.Retrieve(context.TODO(), hash)
            //check that we can read the file size and that it corresponds to the generated file size
            if s, err := reader.Size(nil); err != nil || s != int64(len(randomFiles[i])) {
                allSuccess = false
                log.Warn("Retrieve error", "err", err, "hash", hash, "nodeId", id)
            } else {
                log.Debug(fmt.Sprintf("File with root hash %x successfully retrieved", hash))
            }
        }

        return allSuccess, nil
    }

    //for each tick, run the checks on all nodes
    timingTicker := time.NewTicker(5 * time.Second)
    defer timingTicker.Stop()
    go func() {
        //for live upload, we should wait for uploads to have finished
        //before starting to trigger the checks, due to file size
        if live {
            <-uploadFinished
        }
        for range timingTicker.C {
            for i := 0; i < len(ids); i++ {
                log.Trace(fmt.Sprintf("triggering step %d, id %s", i, ids[i]))
                trigger <- ids[i]
            }
        }
    }()

    log.Info("Starting simulation run...")

    timeout := MaxTimeout * time.Second
    ctx, cancel := context.WithTimeout(context.Background(), timeout)
    defer cancel()

    //run the simulation
    result := simulations.NewSimulation(net).Run(ctx, &simulations.Step{
        Action:  action,
        Trigger: trigger,
        Expect: &simulations.Expectation{
            Nodes: ids,
            Check: check,
        },
    })

    if result.Error != nil {
        return result.Error
    }

    return nil
}

/*
The test generates the given number of chunks.

The upload is done by dependency to the global
`live` and `history` variables;

If `live` is set, first stream subscriptions are established, then
upload to a random node.

If `history` is enabled, first upload then build up subscriptions.

The test loads a snapshot file to construct the swarm network,
assuming that the snapshot file identifies a healthy
kademlia network. Nevertheless a health check runs in the
simulation's `action` function.

The snapshot should have 'streamer' in its service list.
*/
func runRetrievalTest(chunkCount int, nodeCount int) error {
    //for every run (live, history), int the variables
    initRetrievalTest()
    //the ids of the snapshot nodes, initiate only now as we need nodeCount
    ids = make([]discover.NodeID, nodeCount)
    //channel to check for disconnection errors
    disconnectC := make(chan error)
    //channel to close disconnection watcher routine
    quitC := make(chan struct{})
    //the test conf (using same as in `snapshot_sync_test`
    conf = &synctestConfig{}
    //map of overlay address to discover ID
    conf.addrToIdMap = make(map[string]discover.NodeID)
    //array where the generated chunk hashes will be stored
    conf.hashes = make([]storage.Address, 0)
    //load nodes from the snapshot file
    net, err := initNetWithSnapshot(nodeCount)
    if err != nil {
        return err
    }
    var rpcSubscriptionsWg sync.WaitGroup
    //do cleanup after test is terminated
    defer func() {
        //shutdown the snapshot network
        net.Shutdown()
        //after the test, clean up local stores initialized with createLocalStoreForId
        localStoreCleanup()
        //finally clear all data directories
        datadirsCleanup()
    }()
    //get the nodes of the network
    nodes := net.GetNodes()
    //select one index at random...
    idx := rand.Intn(len(nodes))
    //...and get the the node at that index
    //this is the node selected for upload
    uploadNode := nodes[idx]
    //iterate over all nodes...
    for c := 0; c < len(nodes); c++ {
        //create an array of discovery nodeIDS
        ids[c] = nodes[c].ID()
        a := network.ToOverlayAddr(ids[c].Bytes())
        //append it to the array of all overlay addresses
        conf.addrs = append(conf.addrs, a)
        conf.addrToIdMap[string(a)] = ids[c]
    }

    //needed for healthy call
    ppmap = network.NewPeerPotMap(testMinProxBinSize, conf.addrs)

    trigger := make(chan discover.NodeID)
    //simulation action
    action := func(ctx context.Context) error {
        //first run the health check on all nodes,
        //wait until nodes are all healthy
        ticker := time.NewTicker(200 * time.Millisecond)
        defer ticker.Stop()
        for range ticker.C {
            healthy := true
            for _, id := range ids {
                r := registries[id]
                //PeerPot for this node
                addr := common.Bytes2Hex(network.ToOverlayAddr(id.Bytes()))
                pp := ppmap[addr]
                //call Healthy RPC
                h := r.delivery.overlay.Healthy(pp)
                //print info
                log.Debug(r.delivery.overlay.String())
                log.Debug(fmt.Sprintf("IS HEALTHY: %t", h.GotNN && h.KnowNN && h.Full))
                if !h.GotNN || !h.Full {
                    healthy = false
                    break
                }
            }
            if healthy {
                break
            }
        }

        if history {
            log.Info("Uploading for history")
            //If testing only history, we upload the chunk(s) first
            conf.hashes, err = uploadFileToSingleNodeStore(uploadNode.ID(), chunkCount)
            if err != nil {
                return err
            }
        }

        //variables needed to wait for all subscriptions established before uploading
        errc := make(chan error)

        //now setup and start event watching in order to know when we can upload
        ctx, watchCancel := context.WithTimeout(context.Background(), MaxTimeout*time.Second)
        defer watchCancel()

        log.Info("Setting up stream subscription")
        //We need two iterations, one to subscribe to the subscription events
        //(so we know when setup phase is finished), and one to
        //actually run the stream subscriptions. We can't do it in the same iteration,
        //because while the first nodes in the loop are setting up subscriptions,
        //the latter ones have not subscribed to listen to peer events yet,
        //and then we miss events.

        //first iteration: setup disconnection watcher and subscribe to peer events
        for j, id := range ids {
            log.Trace(fmt.Sprintf("Subscribe to subscription events: %d", j))
            client, err := net.GetNode(id).Client()
            if err != nil {
                return err
            }

            //check for `SubscribeMsg` events to know when setup phase is complete
            wsDoneC := watchSubscriptionEvents(ctx, id, client, errc, quitC)
            // doneC is nil, the error happened which is sent to errc channel, already
            if wsDoneC == nil {
                continue
            }
            rpcSubscriptionsWg.Add(1)
            go func() {
                <-wsDoneC
                rpcSubscriptionsWg.Done()
            }()

            //watch for peers disconnecting
            wdDoneC, err := streamTesting.WatchDisconnections(id, client, disconnectC, quitC)
            if err != nil {
                return err
            }
            rpcSubscriptionsWg.Add(1)
            go func() {
                <-wdDoneC
                rpcSubscriptionsWg.Done()
            }()
        }

        //second iteration: start syncing and setup stream subscriptions
        for j, id := range ids {
            log.Trace(fmt.Sprintf("Start syncing and stream subscriptions: %d", j))
            client, err := net.GetNode(id).Client()
            if err != nil {
                return err
            }
            //start syncing!
            var cnt int
            err = client.CallContext(ctx, &cnt, "stream_startSyncing")
            if err != nil {
                return err
            }
            //increment the number of subscriptions we need to wait for
            //by the count returned from startSyncing (SYNC subscriptions)
            subscriptionCount += cnt
            //now also add the number of RETRIEVAL_REQUEST subscriptions
            for snid := range registries[id].peers {
                subscriptionCount++
                err = client.CallContext(ctx, nil, "stream_subscribeStream", snid, NewStream(swarmChunkServerStreamName, "", false), nil, Top)
                if err != nil {
                    return err
                }
            }
        }

        //now wait until the number of expected subscriptions has been finished
        //`watchSubscriptionEvents` will write with a `nil` value to errc
        //every time a `SubscriptionMsg` has been received
        for err := range errc {
            if err != nil {
                return err
            }
            //`nil` received, decrement count
            subscriptionCount--
            //all subscriptions received
            if subscriptionCount == 0 {
                break
            }
        }

        log.Info("Stream subscriptions successfully requested, action terminated")

        if live {
            //now upload the chunks to the selected random single node
            chnks, err := uploadFileToSingleNodeStore(uploadNode.ID(), chunkCount)
            if err != nil {
                return err
            }
            conf.hashes = append(conf.hashes, chnks...)
        }

        return nil
    }

    chunkSize := storage.DefaultChunkSize

    //check defines what will be checked during the test
    check := func(ctx context.Context, id discover.NodeID) (bool, error) {

        //don't check the uploader node
        if id == uploadNode.ID() {
            return true, nil
        }

        select {
        case <-ctx.Done():
            return false, ctx.Err()
        case e := <-disconnectC:
            log.Error(e.Error())
            return false, fmt.Errorf("Disconnect event detected, network unhealthy")
        default:
        }
        log.Trace(fmt.Sprintf("Checking node: %s", id))
        //if there are more than one chunk, test only succeeds if all expected chunks are found
        allSuccess := true

        //check on the node's FileStore (netstore)
        fileStore := registries[id].fileStore
        //check all chunks
        for _, chnk := range conf.hashes {
            reader, _ := fileStore.Retrieve(context.TODO(), chnk)
            //assuming that reading the Size of the chunk is enough to know we found it
            if s, err := reader.Size(nil); err != nil || s != chunkSize {
                allSuccess = false
                log.Warn("Retrieve error", "err", err, "chunk", chnk, "nodeId", id)
            } else {
                log.Debug(fmt.Sprintf("Chunk %x found", chnk))
            }
        }
        return allSuccess, nil
    }

    //for each tick, run the checks on all nodes
    timingTicker := time.NewTicker(5 * time.Second)
    defer timingTicker.Stop()
    go func() {
        for range timingTicker.C {
            for i := 0; i < len(ids); i++ {
                log.Trace(fmt.Sprintf("triggering step %d, id %s", i, ids[i]))
                trigger <- ids[i]
            }
        }
    }()

    log.Info("Starting simulation run...")

    timeout := MaxTimeout * time.Second
    ctx, cancel := context.WithTimeout(context.Background(), timeout)
    defer cancel()

    //run the simulation
    result := simulations.NewSimulation(net).Run(ctx, &simulations.Step{
        Action:  action,
        Trigger: trigger,
        Expect: &simulations.Expectation{
            Nodes: ids,
            Check: check,
        },
    })

    if result.Error != nil {
        return result.Error
    }

    return nil
}

//upload generated files to nodes
//every node gets one file uploaded
func uploadFilesToNodes(nodes []*simulations.Node) ([]storage.Address, []string, error) {
    nodeCnt := len(nodes)
    log.Debug(fmt.Sprintf("Uploading %d files to nodes", nodeCnt))
    //array holding generated files
    rfiles := make([]string, nodeCnt)
    //array holding the root hashes of the files
    rootAddrs := make([]storage.Address, nodeCnt)

    var err error
    //for every node, generate a file and upload
    for i, n := range nodes {
        id := n.ID()
        fileStore := registries[id].fileStore
        //generate a file
        rfiles[i], err = generateRandomFile()
        if err != nil {
            return nil, nil, err
        }
        //store it (upload it) on the FileStore
        ctx := context.TODO()
        rk, wait, err := fileStore.Store(ctx, strings.NewReader(rfiles[i]), int64(len(rfiles[i])), false)
        log.Debug("Uploaded random string file to node")
        if err != nil {
            return nil, nil, err
        }
        err = wait(ctx)
        if err != nil {
            return nil, nil, err
        }
        rootAddrs[i] = rk
    }
    return rootAddrs, rfiles, nil
}

//generate a random file (string)
func generateRandomFile() (string, error) {
    //generate a random file size between minFileSize and maxFileSize
    fileSize := rand.Intn(maxFileSize-minFileSize) + minFileSize
    log.Debug(fmt.Sprintf("Generated file with filesize %d kB", fileSize))
    b := make([]byte, fileSize*1024)
    _, err := crand.Read(b)
    if err != nil {
        log.Error("Error generating random file.", "err", err)
        return "", err
    }
    return string(b), nil
}