path: root/core/bloombits/matcher_test.go

// Copyright 2017 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 bloombits

import (
    "context"
    "math/rand"
    "sync/atomic"
    "testing"
    "time"

    "github.com/ethereum/go-ethereum/common"
)

const testSectionSize = 4096

// Tests that wildcard filter rules (nil) can be specified and are handled well.
func TestMatcherWildcards(t *testing.T) {
    matcher := NewMatcher(testSectionSize, [][][]byte{
        {common.Address{}.Bytes(), common.Address{0x01}.Bytes()}, // Default address is not a wildcard
        {common.Hash{}.Bytes(), common.Hash{0x01}.Bytes()},       // Default hash is not a wildcard
        {common.Hash{0x01}.Bytes()},                              // Plain rule, sanity check
        {common.Hash{0x01}.Bytes(), nil},                         // Wildcard suffix, drop rule
        {nil, common.Hash{0x01}.Bytes()},                         // Wildcard prefix, drop rule
        {nil, nil},                                               // Wildcard combo, drop rule
        {},                                                       // Inited wildcard rule, drop rule
        nil,                                                      // Proper wildcard rule, drop rule
    })
    if len(matcher.filters) != 3 {
        t.Fatalf("filter system size mismatch: have %d, want %d", len(matcher.filters), 3)
    }
    if len(matcher.filters[0]) != 2 {
        t.Fatalf("address clause size mismatch: have %d, want %d", len(matcher.filters[0]), 2)
    }
    if len(matcher.filters[1]) != 2 {
        t.Fatalf("combo topic clause size mismatch: have %d, want %d", len(matcher.filters[1]), 2)
    }
    if len(matcher.filters[2]) != 1 {
        t.Fatalf("singletone topic clause size mismatch: have %d, want %d", len(matcher.filters[2]), 1)
    }
}

// Tests the matcher pipeline on a single continuous workflow without interrupts.
func TestMatcherContinuous(t *testing.T) {
    testMatcherDiffBatches(t, [][]bloomIndexes{{{10, 20, 30}}}, 0, 100000, false, 75)
    testMatcherDiffBatches(t, [][]bloomIndexes{{{32, 3125, 100}}, {{40, 50, 10}}}, 0, 100000, false, 81)
    testMatcherDiffBatches(t, [][]bloomIndexes{{{4, 8, 11}, {7, 8, 17}}, {{9, 9, 12}, {15, 20, 13}}, {{18, 15, 15}, {12, 10, 4}}}, 0, 10000, false, 36)
}

// Tests the matcher pipeline on a constantly interrupted and resumed work pattern
// with the aim of ensuring data items are requested only once.
func TestMatcherIntermittent(t *testing.T) {
    testMatcherDiffBatches(t, [][]bloomIndexes{{{10, 20, 30}}}, 0, 100000, true, 75)
    testMatcherDiffBatches(t, [][]bloomIndexes{{{32, 3125, 100}}, {{40, 50, 10}}}, 0, 100000, true, 81)
    testMatcherDiffBatches(t, [][]bloomIndexes{{{4, 8, 11}, {7, 8, 17}}, {{9, 9, 12}, {15, 20, 13}}, {{18, 15, 15}, {12, 10, 4}}}, 0, 10000, true, 36)
}

// Tests the matcher pipeline on random input to hopefully catch anomalies.
func TestMatcherRandom(t *testing.T) {
    for i := 0; i < 10; i++ {
        testMatcherBothModes(t, makeRandomIndexes([]int{1}, 50), 0, 10000, 0)
        testMatcherBothModes(t, makeRandomIndexes([]int{3}, 50), 0, 10000, 0)
        testMatcherBothModes(t, makeRandomIndexes([]int{2, 2, 2}, 20), 0, 10000, 0)
        testMatcherBothModes(t, makeRandomIndexes([]int{5, 5, 5}, 50), 0, 10000, 0)
        testMatcherBothModes(t, makeRandomIndexes([]int{4, 4, 4}, 20), 0, 10000, 0)
    }
}

// Tests that the matcher can properly find matches if the starting block is
// shifter from a multiple of 8. This is needed to cover an optimisation with
// bitset matching https://github.com/ethereum/go-ethereum/issues/15309.
func TestMatcherShifted(t *testing.T) {
    // Block 0 always matches in the tests, skip ahead of first 8 blocks with the
    // start to get a potential zero byte in the matcher bitset.

    // To keep the second bitset byte zero, the filter must only match for the first
    // time in block 16, so doing an all-16 bit filter should suffice.

    // To keep the starting block non divisible by 8, block number 9 is the first
    // that would introduce a shift and not match block 0.
    testMatcherBothModes(t, [][]bloomIndexes{{{16, 16, 16}}}, 9, 64, 0)
}

// Tests that matching on everything doesn't crash (special case internally).
func TestWildcardMatcher(t *testing.T) {
    testMatcherBothModes(t, nil, 0, 10000, 0)
}

// makeRandomIndexes generates a random filter system, composed on multiple filter
// criteria, each having one bloom list component for the address and arbitrarily
// many topic bloom list components.
func makeRandomIndexes(lengths []int, max int) [][]bloomIndexes {
    res := make([][]bloomIndexes, len(lengths))
    for i, topics := range lengths {
        res[i] = make([]bloomIndexes, topics)
        for j := 0; j < topics; j++ {
            for k := 0; k < len(res[i][j]); k++ {
                res[i][j][k] = uint(rand.Intn(max-1) + 2)
            }
        }
    }
    return res
}

// testMatcherDiffBatches runs the given matches test in single-delivery and also
// in batches delivery mode, verifying that all kinds of deliveries are handled
// correctly withn.
func testMatcherDiffBatches(t *testing.T, filter [][]bloomIndexes, start, blocks uint64, intermittent bool, retrievals uint32) {
    singleton := testMatcher(t, filter, start, blocks, intermittent, retrievals, 1)
    batched := testMatcher(t, filter, start, blocks, intermittent, retrievals, 16)

    if singleton != batched {
        t.Errorf("filter = %v blocks = %v intermittent = %v: request count mismatch, %v in signleton vs. %v in batched mode", filter, blocks, intermittent, singleton, batched)
    }
}

// testMatcherBothModes runs the given matcher test in both continuous as well as
// in intermittent mode, verifying that the request counts match each other.
func testMatcherBothModes(t *testing.T, filter [][]bloomIndexes, start, blocks uint64, retrievals uint32) {
    continuous := testMatcher(t, filter, start, blocks, false, retrievals, 16)
    intermittent := testMatcher(t, filter, start, blocks, true, retrievals, 16)

    if continuous != intermittent {
        t.Errorf("filter = %v blocks = %v: request count mismatch, %v in continuous vs. %v in intermittent mode", filter, blocks, continuous, intermittent)
    }
}

// testMatcher is a generic tester to run the given matcher test and return the
// number of requests made for cross validation between different modes.
func testMatcher(t *testing.T, filter [][]bloomIndexes, start, blocks uint64, intermittent bool, retrievals uint32, maxReqCount int) uint32 {
    // Create a new matcher an simulate our explicit random bitsets
    matcher := NewMatcher(testSectionSize, nil)
    matcher.filters = filter

    for _, rule := range filter {
        for _, topic := range rule {
            for _, bit := range topic {
                matcher.addScheduler(bit)
            }
        }
    }
    // Track the number of retrieval requests made
    var requested uint32

    // Start the matching session for the filter and the retriever goroutines
    quit := make(chan struct{})
    matches := make(chan uint64, 16)

    session, err := matcher.Start(context.Background(), start, blocks-1, matches)
    if err != nil {
        t.Fatalf("failed to stat matcher session: %v", err)
    }
    startRetrievers(session, quit, &requested, maxReqCount)

    // Iterate over all the blocks and verify that the pipeline produces the correct matches
    for i := start; i < blocks; i++ {
        if expMatch3(filter, i) {
            match, ok := <-matches
            if !ok {
                t.Errorf("filter = %v  blocks = %v  intermittent = %v: expected #%v, results channel closed", filter, blocks, intermittent, i)
                return 0
            }
            if match != i {
                t.Errorf("filter = %v  blocks = %v  intermittent = %v: expected #%v, got #%v", filter, blocks, intermittent, i, match)
            }
            // If we're testing intermittent mode, abort and restart the pipeline
            if intermittent {
                session.Close()
                close(quit)

                quit = make(chan struct{})
                matches = make(chan uint64, 16)

                session, err = matcher.Start(context.Background(), i+1, blocks-1, matches)
                if err != nil {
                    t.Fatalf("failed to stat matcher session: %v", err)
                }
                startRetrievers(session, quit, &requested, maxReqCount)
            }
        }
    }
    // Ensure the result channel is torn down after the last block
    match, ok := <-matches
    if ok {
        t.Errorf("filter = %v  blocks = %v  intermittent = %v: expected closed channel, got #%v", filter, blocks, intermittent, match)
    }
    // Clean up the session and ensure we match the expected retrieval count
    session.Close()
    close(quit)

    if retrievals != 0 && requested != retrievals {
        t.Errorf("filter = %v  blocks = %v  intermittent = %v: request count mismatch, have #%v, want #%v", filter, blocks, intermittent, requested, retrievals)
    }
    return requested
}

// startRetrievers starts a batch of goroutines listening for section requests
// and serving them.
func startRetrievers(session *MatcherSession, quit chan struct{}, retrievals *uint32, batch int) {
    requests := make(chan chan *Retrieval)

    for i := 0; i < 10; i++ {
        // Start a multiplexer to test multiple threaded execution
        go session.Multiplex(batch, 100*time.Microsecond, requests)

        // Start a services to match the above multiplexer
        go func() {
            for {
                // Wait for a service request or a shutdown
                select {
                case <-quit:
                    return

                case request := <-requests:
                    task := <-request

                    task.Bitsets = make([][]byte, len(task.Sections))
                    for i, section := range task.Sections {
                        if rand.Int()%4 != 0 { // Handle occasional missing deliveries
                            task.Bitsets[i] = generateBitset(task.Bit, section)
                            atomic.AddUint32(retrievals, 1)
                        }
                    }
                    request <- task
                }
            }
        }()
    }
}

// generateBitset generates the rotated bitset for the given bloom bit and section
// numbers.
func generateBitset(bit uint, section uint64) []byte {
    bitset := make([]byte, testSectionSize/8)
    for i := 0; i < len(bitset); i++ {
        for b := 0; b < 8; b++ {
            blockIdx := section*testSectionSize + uint64(i*8+b)
            bitset[i] += bitset[i]
            if (blockIdx % uint64(bit)) == 0 {
                bitset[i]++
            }
        }
    }
    return bitset
}

func expMatch1(filter bloomIndexes, i uint64) bool {
    for _, ii := range filter {
        if (i % uint64(ii)) != 0 {
            return false
        }
    }
    return true
}

func expMatch2(filter []bloomIndexes, i uint64) bool {
    for _, ii := range filter {
        if expMatch1(ii, i) {
            return true
        }
    }
    return false
}

func expMatch3(filter [][]bloomIndexes, i uint64) bool {
    for _, ii := range filter {
        if !expMatch2(ii, i) {
            return false
        }
    }
    return true
}