Add end to end test for fault detector (#29)

* :WIP: Add e2e test

* :WIP: Mock client

* 🔨 Refactor code for e2e tests

* :WIP: Fix tests

* Update Makefile

* Resolve TODOs

* 👌 Applied suggestions

* Implement/expose functions

* 👌 Applied suggestions

* Update launch.json file

.vscode/launch.json

@@ -9,9 +9,10 @@
             "type": "go",
             "request": "launch",
             "mode": "auto",
-            "program": "${workspaceRoot}/cmd",
+            "cwd": "${workspaceFolder}",
+            "program": "${workspaceRoot}/cmd/faultdetector",
             "args": ["--config", "./config.yaml"],
             "showLog": true
         }
     ]
-}
+}

Makefile

@@ -34,6 +34,10 @@ test.coverage: test
 
 test.coverage.html: test
 	go tool cover -html=coverage.out
+
+test.e2e: # Runs e2e tests
+	@echo "Test e2e"
+	@go test -v ./cmd/$(APP_NAME)
 
 lint: # Runs golangci-lint on the repo
 	@go install github.com/golangci/golangci-lint/cmd/golangci-lint@latest

cmd/faultdetector/main_test.go

@@ -0,0 +1,301 @@
+package main
+
+import (
+	"context"
+	crand "crypto/rand"
+	"fmt"
+	"io"
+	"math/big"
+	"math/rand"
+	"net/http"
+	"strconv"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/LiskHQ/op-fault-detector/pkg/api"
+	"github.com/LiskHQ/op-fault-detector/pkg/chain"
+	"github.com/LiskHQ/op-fault-detector/pkg/config"
+	"github.com/LiskHQ/op-fault-detector/pkg/faultdetector"
+	"github.com/LiskHQ/op-fault-detector/pkg/log"
+	"github.com/LiskHQ/op-fault-detector/pkg/utils/notification"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/gin-gonic/gin"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+	promClient "github.com/prometheus/client_model/go"
+	"github.com/prometheus/common/expfmt"
+	slackClient "github.com/slack-go/slack"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/mock"
+)
+
+const (
+	host                                = "127.0.0.1"
+	port                                = 8088
+	faultProofWindow                    = 1000
+	currentOutputIndex                  = 1
+	l1RpcApi                            = "https://rpc.notadegen.com/eth"
+	l2RpcApi                            = "https://mainnet.optimism.io/"
+	faultDetectorStateMismatchMetricKey = "fault_detector_is_state_mismatch"
+	metricValue                         = "value"
+	postMessageContextFnName            = "PostMessageContext"
+	channelID                           = "TestChannelID"
+)
+
+type parsedMetricMap map[string]map[string]interface{}
+
+type mockContractOracleAccessor struct {
+	mock.Mock
+}
+
+type mockSlackClient struct {
+	mock.Mock
+}
+
+func (o *mockContractOracleAccessor) GetNextOutputIndex() (*big.Int, error) {
+	called := o.MethodCalled("GetNextOutputIndex")
+	return called.Get(0).(*big.Int), called.Error(1)
+}
+
+func (o *mockContractOracleAccessor) GetL2Output(index *big.Int) (chain.L2Output, error) {
+	called := o.MethodCalled("GetL2Output", index)
+	return called.Get(0).(chain.L2Output), called.Error(1)
+}
+
+func (o *mockContractOracleAccessor) FinalizationPeriodSeconds() (*big.Int, error) {
+	called := o.MethodCalled("FinalizationPeriodSeconds")
+	return called.Get(0).(*big.Int), called.Error(1)
+}
+
+func (o *mockSlackClient) PostMessageContext(ctx context.Context, channelID string, options ...slackClient.MsgOption) (string, string, error) {
+	called := o.MethodCalled(postMessageContextFnName)
+	return called.Get(0).(string), called.Get(1).(string), called.Error(2)
+}
+
+var slackNotificationClient *mockSlackClient = new(mockSlackClient)
+
+func randHash() (out common.Hash) {
+	_, _ = crand.Read(out[:])
+	return out
+}
+
+func randTimestamp() (out uint64) {
+	timestamp := uint64(rand.Int63n(time.Now().Unix()))
+	return timestamp
+}
+
+func prepareHTTPServer(t *testing.T, ctx context.Context, logger log.Logger, config *config.Config, wg *sync.WaitGroup, erroChan chan error) *api.HTTPServer {
+	testServer := api.NewHTTPServer(ctx, logger, wg, config, erroChan)
+	return testServer
+}
+
+func prepareNotification(t *testing.T, ctx context.Context, logger log.Logger, config *config.Config) *notification.Notification {
+	slackNotificationClient.On(postMessageContextFnName).Return(channelID, "1234569.1000", nil)
+	testNotificationService := notification.GetNotification(ctx, logger, slackNotificationClient, config.Notification)
+	return testNotificationService
+}
+
+func prepareFaultDetector(t *testing.T, ctx context.Context, logger log.Logger, testNotificationService *notification.Notification, wg *sync.WaitGroup, reg *prometheus.Registry, config *config.Config, erroChan chan error, mock bool) *faultdetector.FaultDetector {
+	var fd *faultdetector.FaultDetector
+	if !mock {
+		fd, _ = faultdetector.NewFaultDetector(ctx, logger, erroChan, wg, config.FaultDetectorConfig, reg, testNotificationService)
+	} else {
+		metrics := faultdetector.NewFaultDetectorMetrics(reg)
+
+		// Create chain API clients
+		l1RpcApi, err := chain.GetAPIClient(ctx, l1RpcApi, logger)
+		if err != nil {
+			panic(err)
+		}
+		l2RpcApi, err := chain.GetAPIClient(ctx, l2RpcApi, logger)
+		if err != nil {
+			panic(err)
+		}
+
+		latestL2BlockNumber, err := l2RpcApi.GetLatestBlockNumber(ctx)
+		if err != nil {
+			panic(err)
+		}
+
+		// Mock oracle contract accessor
+		var oracle *mockContractOracleAccessor = new(mockContractOracleAccessor)
+		oracle.On("GetNextOutputIndex").Return(big.NewInt(2), nil)
+		oracle.On("FinalizationPeriodSeconds").Return(faultProofWindow, nil)
+		oracle.On("GetL2Output", big.NewInt(0)).Return(chain.L2Output{
+			OutputRoot:    randHash().String(),
+			L1Timestamp:   randTimestamp(),
+			L2BlockNumber: latestL2BlockNumber,
+			L2OutputIndex: 2,
+		}, nil)
+		oracle.On("GetL2Output", big.NewInt(1)).Return(chain.L2Output{
+			OutputRoot:    randHash().String(),
+			L1Timestamp:   randTimestamp(),
+			L2BlockNumber: latestL2BlockNumber,
+			L2OutputIndex: 2,
+		}, nil)
+
+		fd = faultdetector.GetFaultDetector(ctx, logger, l1RpcApi, l2RpcApi, oracle, faultProofWindow, currentOutputIndex, metrics, testNotificationService, false, wg, erroChan)
+	}
+
+	return fd
+}
+
+func prepareConfig(t *testing.T) *config.Config {
+	serverPort, err := strconv.Atoi(fmt.Sprintf("%d", port))
+	if err != nil {
+		panic(err)
+	}
+
+	return &config.Config{
+		System: &config.System{
+			LogLevel: "info",
+		},
+		Api: &config.Api{
+			Server: &config.Server{
+				Host: host,
+				Port: uint(serverPort),
+			},
+			BasePath:         "/api",
+			RegisterVersions: []string{"v1"},
+		},
+		FaultDetectorConfig: &config.FaultDetectorConfig{
+			L1RPCEndpoint:                 l1RpcApi,
+			L2RPCEndpoint:                 l2RpcApi,
+			StartBatchIndex:               -1,
+			L2OutputOracleContractAddress: "0x0000000000000000000000000000000000000000",
+		},
+		Notification: &config.Notification{
+			Enable: true,
+			Slack: &config.SlackConfig{
+				ChannelID: channelID,
+			},
+		},
+	}
+}
+
+func parseMetricRes(input *strings.Reader) []parsedMetricMap {
+	parser := &expfmt.TextParser{}
+	metricFamilies, err := parser.TextToMetricFamilies(input)
+	if err != nil {
+		panic(err)
+	}
+
+	var parsedOutput []parsedMetricMap
+	for _, metricFamily := range metricFamilies {
+		for _, m := range metricFamily.GetMetric() {
+			metric := make(map[string]interface{})
+			for _, label := range m.GetLabel() {
+				metric[label.GetName()] = label.GetValue()
+			}
+			switch metricFamily.GetType() {
+			case promClient.MetricType_COUNTER:
+				metric[metricValue] = m.GetCounter().GetValue()
+			case promClient.MetricType_GAUGE:
+				metric[metricValue] = m.GetGauge().GetValue()
+			}
+			parsedOutput = append(parsedOutput, parsedMetricMap{
+				metricFamily.GetName(): metric,
+			})
+		}
+	}
+
+	return parsedOutput
+}
+
+func TestMain_E2E(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	client := http.DefaultClient
+
+	tests := []struct {
+		name      string
+		mock      bool
+		assertion func(float64, error)
+	}{
+		{
+			name: "should start application with no faults detected",
+			mock: false,
+			assertion: func(isStateMismatch float64, err error) {
+				const expected float64 = 0
+				assert.Equal(t, isStateMismatch, expected)
+				slackNotificationClient.AssertNotCalled(t, postMessageContextFnName)
+			},
+		},
+		{
+			name: "should start application with faults detected",
+			mock: true,
+			assertion: func(isStateMismatch float64, err error) {
+				const expected float64 = 1
+				assert.Equal(t, isStateMismatch, expected)
+				slackNotificationClient.AssertCalled(t, postMessageContextFnName)
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := context.Background()
+			wg := sync.WaitGroup{}
+			logger, err := log.NewDefaultProductionLogger()
+			if err != nil {
+				panic(err)
+			}
+
+			errorChan := make(chan error)
+			registry := prometheus.NewRegistry()
+			testConfig := prepareConfig(&testing.T{})
+			testServer := prepareHTTPServer(&testing.T{}, ctx, logger, testConfig, &wg, errorChan)
+			testNotificationService := prepareNotification(&testing.T{}, ctx, logger, testConfig)
+			testFaultDetector := prepareFaultDetector(&testing.T{}, ctx, logger, testNotificationService, &wg, registry, testConfig, errorChan, tt.mock)
+
+			testServer.RegisterHandler("GET", "/metrics", promhttp.HandlerFor(registry, promhttp.HandlerOpts{Registry: registry, ProcessStartTime: time.Now()}))
+
+			app := &App{
+				ctx:           ctx,
+				logger:        logger,
+				errChan:       errorChan,
+				config:        testConfig,
+				wg:            &wg,
+				apiServer:     testServer,
+				faultDetector: testFaultDetector,
+				notification:  testNotificationService,
+			}
+
+			time.AfterFunc(5*time.Second, func() {
+				statusEndpoint := fmt.Sprintf("http://%s:%d/api/v1/status", host, port)
+				req, err := http.NewRequest(http.MethodGet, statusEndpoint, nil)
+				assert.NoError(t, err)
+				res, err := client.Do(req)
+				assert.NoError(t, err)
+				assert.Equal(t, 200, res.StatusCode)
+
+				metricsEndpoint := fmt.Sprintf("http://%s:%d/metrics", host, port)
+				req, err = http.NewRequest(http.MethodGet, metricsEndpoint, nil)
+				assert.NoError(t, err)
+				assert.Equal(t, 200, res.StatusCode)
+
+				res, err = client.Do(req)
+				assert.NoError(t, err)
+				body, err := io.ReadAll(res.Body)
+				assert.NoError(t, err)
+				parsedMetric := parseMetricRes(strings.NewReader(string(body)))
+				for _, m := range parsedMetric {
+					if m[faultDetectorStateMismatchMetricKey] != nil {
+						isStateMismatch := m[faultDetectorStateMismatchMetricKey][metricValue].(float64)
+						tt.assertion(isStateMismatch, nil)
+					}
+				}
+
+				app.stop()
+				wg.Done()
+			})
+
+			wg.Add(1)
+			go func() {
+				app.Start()
+			}()
+			wg.Wait()
+		})
+	}
+}

go.mod

@@ -73,8 +73,8 @@ require (
 	github.com/pelletier/go-toml/v2 v2.1.1 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
-	github.com/prometheus/client_model v0.5.0 // indirect
-	github.com/prometheus/common v0.45.0 // indirect
+	github.com/prometheus/client_model v0.5.0
+	github.com/prometheus/common v0.45.0
 	github.com/prometheus/procfs v0.12.0 // indirect
 	github.com/rivo/uniseg v0.4.3 // indirect
 	github.com/rogpeppe/go-internal v1.10.0 // indirect

pkg/config/config.go

@@ -52,7 +52,7 @@ type Server struct {
 type FaultDetectorConfig struct {
 	L1RPCEndpoint                 string `mapstructure:"l1_rpc_endpoint"`
 	L2RPCEndpoint                 string `mapstructure:"l2_rpc_endpoint"`
-	Startbatchindex               int64  `mapstructure:"start_batch_index"`
+	StartBatchIndex               int64  `mapstructure:"start_batch_index"`
 	L2OutputOracleContractAddress string `mapstructure:"l2_output_oracle_contract_address"`
 }