chore: increase test coverage (#2349)

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## Overview

This pr adds some error case testing in order to meet the minimum of 80%
code coverage

ref #2256 


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

- **Tests**
- Added extensive new tests to improve error handling verification in
the store and node components.
  - Introduced tests for instrumentation server startup and validation.
- Enhanced test configuration to explicitly initialize instrumentation
settings.
- **Chores**
- Updated configuration to exclude additional directories from code
coverage reporting.
- **Refactor**
  - Simplified process exit logic by removing internal helper functions.
- **Bug Fixes**
- Clarified error messages related to state serialization to accurately
reflect protobuf usage.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: tac0turtle <you@example.com>
Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

Author: 3 people

codecov.yml

@@ -11,4 +11,7 @@ ignore:
   - "types/pb"
   - "scripts/"
   - "pkg/rpc/example/"
+  - "apps"
   - "da/internal/mocks"
+  - "da/cmd"
+  - "execution/evm" # EVM is covered in e2e/integration tests

node/full_node_test.go

@@ -0,0 +1,78 @@
+package node
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"testing"
+	"time"
+
+	"cosmossdk.io/log"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/rollkit/rollkit/pkg/service"
+)
+
+func TestStartInstrumentationServer(t *testing.T) {
+	t.Parallel()
+	require := require.New(t)
+	assert := assert.New(t)
+
+	var config = getTestConfig(t, 1)
+	config.Instrumentation.Prometheus = true
+	config.Instrumentation.PrometheusListenAddr = "127.0.0.1:26660"
+	config.Instrumentation.Pprof = true
+	config.Instrumentation.PprofListenAddr = "127.0.0.1:26661"
+
+	node := &FullNode{
+		nodeConfig:  config,
+		BaseService: *service.NewBaseService(log.NewTestLogger(t), "TestNode", nil),
+	}
+
+	prometheusSrv, pprofSrv := node.startInstrumentationServer()
+
+	require.NotNil(prometheusSrv, "Prometheus server should be initialized")
+	require.NotNil(pprofSrv, "Pprof server should be initialized")
+
+	time.Sleep(100 * time.Millisecond)
+
+	resp, err := http.Get(fmt.Sprintf("http://%s/metrics", config.Instrumentation.PrometheusListenAddr))
+	require.NoError(err, "Failed to get Prometheus metrics")
+	defer func() {
+		err := resp.Body.Close()
+		if err != nil {
+			t.Logf("Error closing response body: %v", err)
+		}
+	}()
+	assert.Equal(http.StatusOK, resp.StatusCode, "Prometheus metrics endpoint should return 200 OK")
+	body, err := io.ReadAll(resp.Body)
+	require.NoError(err)
+	assert.Contains(string(body), "# HELP", "Prometheus metrics body should contain HELP lines") // Check for typical metrics content
+
+	resp, err = http.Get(fmt.Sprintf("http://%s/debug/pprof/", config.Instrumentation.PprofListenAddr))
+	require.NoError(err, "Failed to get Pprof index")
+	defer func() {
+		err := resp.Body.Close()
+		if err != nil {
+			t.Logf("Error closing response body: %v", err)
+		}
+	}()
+	assert.Equal(http.StatusOK, resp.StatusCode, "Pprof index endpoint should return 200 OK")
+	body, err = io.ReadAll(resp.Body)
+	require.NoError(err)
+	assert.Contains(string(body), "Types of profiles available", "Pprof index body should contain expected text")
+
+	shutdownCtx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
+	defer cancel()
+
+	if prometheusSrv != nil {
+		err = prometheusSrv.Shutdown(shutdownCtx)
+		assert.NoError(err, "Prometheus server shutdown should not return error")
+	}
+	if pprofSrv != nil {
+		err = pprofSrv.Shutdown(shutdownCtx)
+		assert.NoError(err, "Pprof server shutdown should not return error")
+	}
+}

node/helpers_test.go

@@ -88,7 +88,8 @@ func getTestConfig(t *testing.T, n int) rollkitconfig.Config {
 		RPC: rollkitconfig.RPCConfig{
 			Address: fmt.Sprintf("127.0.0.1:%d", 8000+n),
 		},
-		ChainID: "test-chain",
+		ChainID:         "test-chain",
+		Instrumentation: &rollkitconfig.InstrumentationConfig{},
 	}
 }
 

pkg/os/os.go

@@ -29,21 +29,6 @@ func TrapSignal(logger logger, cb func()) {
 	}()
 }
 
-// Kill the running process by sending itself SIGTERM.
-func Kill() error {
-	p, err := os.FindProcess(os.Getpid())
-	if err != nil {
-		return err
-	}
-	return p.Signal(syscall.SIGTERM)
-}
-
-// Exit exits the program with a message and a status code of 1.
-func Exit(s string) {
-	fmt.Println(s)
-	os.Exit(1)
-}
-
 // EnsureDir ensures the given directory exists, creating it if necessary.
 // Errors if the path already exists as a non-directory.
 func EnsureDir(dir string, mode os.FileMode) error {
@@ -69,7 +54,8 @@ func ReadFile(filePath string) ([]byte, error) {
 func MustReadFile(filePath string) []byte {
 	fileBytes, err := os.ReadFile(filePath) //nolint:gosec
 	if err != nil {
-		Exit(fmt.Sprintf("MustReadFile failed: %v", err))
+		fmt.Printf("MustReadFile failed: %v", err)
+		os.Exit(1)
 		return nil
 	}
 	return fileBytes
@@ -84,7 +70,8 @@ func WriteFile(filePath string, contents []byte, mode os.FileMode) error {
 func MustWriteFile(filePath string, contents []byte, mode os.FileMode) {
 	err := WriteFile(filePath, contents, mode)
 	if err != nil {
-		Exit(fmt.Sprintf("MustWriteFile failed: %v", err))
+		fmt.Printf("MustWriteFile failed: %v", err)
+		os.Exit(1)
 	}
 }
 

pkg/store/store.go

@@ -184,11 +184,11 @@ func (s *DefaultStore) GetSignature(ctx context.Context, height uint64) (*types.
 func (s *DefaultStore) UpdateState(ctx context.Context, state types.State) error {
 	pbState, err := state.ToProto()
 	if err != nil {
-		return fmt.Errorf("failed to marshal state to JSON: %w", err)
+		return fmt.Errorf("failed to convert type state to protobuf type: %w", err)
 	}
 	data, err := proto.Marshal(pbState)
 	if err != nil {
-		return err
+		return fmt.Errorf("failed to marshal state to protobuf: %w", err)
 	}
 	return s.db.Put(ctx, ds.NewKey(getStateKey()), data)
 }
@@ -202,7 +202,7 @@ func (s *DefaultStore) GetState(ctx context.Context) (types.State, error) {
 	var pbState pb.State
 	err = proto.Unmarshal(blob, &pbState)
 	if err != nil {
-		return types.State{}, fmt.Errorf("failed to unmarshal state from JSON: %w", err)
+		return types.State{}, fmt.Errorf("failed to unmarshal state from protobuf: %w", err)
 	}
 
 	var state types.State