feat: CacheDir is configurable (#18)

pkg/config/config.go

@@ -21,8 +21,8 @@ import (
 )
 
 const (
-	CacheDir = "/var/lib/yara-rule-server"
-	RulePath = "/var/lib/yara-rule-server/compiled"
+	CompiledRuleFileName = "compiled"
+	TempDirName          = "tmp"
 )
 
 type Config struct {
@@ -33,6 +33,7 @@ type Config struct {
 	RuleUpdateSchedule        string       `mapstructure:"rule_update_schedule"`
 	ServerAddress             string       `mapstructure:"server_address"`
 	HealthCheckAddressAddress string       `mapstructure:"health_check_address"`
+	CacheDir                  string       `mapstructure:"cache_dir"`
 }
 
 type RuleSource struct {
@@ -71,4 +72,5 @@ func setDefaults() {
 	viper.SetDefault("rule_update_schedule", "0 0 * * *")
 	viper.SetDefault("server_address", ":8080")
 	viper.SetDefault("health_check_address", ":8082")
+	viper.SetDefault("cache_dir", "/var/lib/yara-rule-server")
 }

pkg/fileserver/fileserver.go

@@ -18,16 +18,18 @@ package fileserver
 import (
 	"errors"
 	"net/http"
+	"path"
 
 	"github.com/sirupsen/logrus"
 
 	"github.com/openclarity/yara-rule-server/pkg/config"
 )
 
 func Start(cfg *config.Config, logger *logrus.Entry) *http.Server {
-	logger.Infof("Starting file server. Rule file: %s", config.RulePath)
+	compiledRulePath := path.Join(cfg.CacheDir, config.CompiledRuleFileName)
+	logger.Infof("Starting file server. Rule file: %s", compiledRulePath)
 	sFile := func(w http.ResponseWriter, req *http.Request) {
-		http.ServeFile(w, req, config.RulePath)
+		http.ServeFile(w, req, compiledRulePath)
 	}
 
 	http.HandleFunc("/", sFile)

pkg/rules/compile.go

@@ -20,6 +20,7 @@ import (
 	"io/fs"
 	"os"
 	"os/exec"
+	"path"
 	"path/filepath"
 	"regexp"
 	"strings"
@@ -56,7 +57,7 @@ func createYarFileListToIndex(sourceDir string, reg *regexp.Regexp) ([]string, e
 	return yarFilesToIndex, err
 }
 
-func generateIndexAndCompile(yaracPATH string, yarFilesToIndex []string, tempDir string) error {
+func generateIndexAndCompile(cfg *config.Config, yarFilesToIndex []string, tempDir string) error {
 	// Write index file so that we can pass it to yarac
 	tmpIndexFile, err := os.CreateTemp(tempDir, "index")
 	if err != nil {
@@ -73,7 +74,7 @@ func generateIndexAndCompile(yaracPATH string, yarFilesToIndex []string, tempDir
 	if err != nil {
 		return fmt.Errorf("failed to create temp file: %v", err)
 	}
-	err = compile(yaracPATH, tmpIndexFile.Name(), tmpCompiledFile.Name())
+	err = compile(cfg.YaracPath, tmpIndexFile.Name(), tmpCompiledFile.Name())
 	if err != nil {
 		return fmt.Errorf("failed to compile %s: %v", tmpIndexFile.Name(), err)
 	}
@@ -83,7 +84,8 @@ func generateIndexAndCompile(yaracPATH string, yarFilesToIndex []string, tempDir
 
 	// Now we have the compile rules atomically move
 	// it into the location to be served by the http server.
-	if err := os.Rename(tmpCompiledFile.Name(), config.RulePath); err != nil {
+	compiledRulePath := path.Join(cfg.CacheDir, config.CompiledRuleFileName)
+	if err := os.Rename(tmpCompiledFile.Name(), compiledRulePath); err != nil {
 		return fmt.Errorf("failed to move compiled yara rules: %v", err)
 	}
 

pkg/rules/rules.go

@@ -32,13 +32,13 @@ import (
 func DownloadAndCompile(cfg *config.Config, logger *logrus.Entry) error {
 	// First try to download new copies of all the sources
 	yarFilesToIndex := make([]string, 0)
-	tempDir := path.Join(config.CacheDir, "tmp")
+	tempDir := path.Join(cfg.CacheDir, config.TempDirName)
 	if err := os.MkdirAll(tempDir, 0755); err != nil {
 		return fmt.Errorf("failed to create yara rule server temp directory. tempDir=%s: %v", tempDir, err)
 	}
 	for _, source := range cfg.RuleSources {
 		// Create directory for this source if it doesn't exist
-		sourceDir := path.Join(config.CacheDir, "sources", source.Name)
+		sourceDir := path.Join(cfg.CacheDir, "sources", source.Name)
 		if err := os.MkdirAll(sourceDir, 0755); err != nil {
 			logger.WithError(err).Errorf("Failed to create directory %s. Using the last successful download if available", sourceDir)
 			continue
@@ -67,7 +67,7 @@ func DownloadAndCompile(cfg *config.Config, logger *logrus.Entry) error {
 		yarFilesToIndex = append(yarFilesToIndex, yarFiles...)
 	}
 
-	if err := generateIndexAndCompile(cfg.YaracPath, yarFilesToIndex, tempDir); err != nil {
+	if err := generateIndexAndCompile(cfg, yarFilesToIndex, tempDir); err != nil {
 		return fmt.Errorf("failed to create compiled rules: %v", err)
 	}