add ability to load rulesets from directory

cmd/main.go

@@ -36,6 +36,11 @@ func main() {
 		Help:     "This will spawn multiple processes listening",
 	})
 
+	ruleset := parser.String("r", "ruleset", &argparse.Options{
+		Required: false,
+		Help:     "File, Directory or URL to a ruleset.yml. Overrides RULESET environment variable.",
+	})
+
 	err := parser.Parse(os.Args)
 	if err != nil {
 		fmt.Print(parser.Usage(err))
@@ -80,7 +85,7 @@ func main() {
 	app.Get("raw/*", handlers.Raw)
 	app.Get("api/*", handlers.Api)
 	app.Get("ruleset", handlers.Raw)
-	app.Get("/*", handlers.ProxySite)
+	app.Get("/*", handlers.ProxySite(*ruleset))
 
 	log.Fatal(app.Listen(":" + *port))
 }

handlers/proxy.go

@@ -10,19 +10,36 @@ import (
 	"regexp"
 	"strings"
 
+	"ladder/pkg/ruleset"
+
 	"github.com/PuerkitoBio/goquery"
 	"github.com/gofiber/fiber/v2"
-	"gopkg.in/yaml.v3"
 )
 
 var (
 	UserAgent      = getenv("USER_AGENT", "Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)")
 	ForwardedFor   = getenv("X_FORWARDED_FOR", "66.249.66.1")
-	rulesSet       = loadRules()
+	rulesSet       = ruleset.NewRulesetFromEnv()
-	allowedDomains = strings.Split(os.Getenv("ALLOWED_DOMAINS"), ",")
+	allowedDomains = []string{}
 )
 
-func ProxySite(c *fiber.Ctx) error {
+func init() {
+	allowedDomains = strings.Split(os.Getenv("ALLOWED_DOMAINS"), ",")
+	if os.Getenv("ALLOWED_DOMAINS_RULESET") == "true" {
+		allowedDomains = append(allowedDomains, rulesSet.Domains()...)
+	}
+}
+
+func ProxySite(rulesetPath string) fiber.Handler {
+	if rulesetPath != "" {
+		rs, err := ruleset.NewRuleset(rulesetPath)
+		if err != nil {
+			panic(err)
+		}
+		rulesSet = rs
+	}
+
+	return func(c *fiber.Ctx) error {
 		// Get the url from the URL
 		url := c.Params("*")
 
@@ -38,6 +55,7 @@ func ProxySite(c *fiber.Ctx) error {
 		c.Set("Content-Security-Policy", resp.Header.Get("Content-Security-Policy"))
 
 		return c.SendString(body)
+	}
 }
 
 func fetchSite(urlpath string, queries map[string]string) (string, *http.Request, *http.Response, error) {
@@ -122,7 +140,7 @@ func fetchSite(urlpath string, queries map[string]string) (string, *http.Request
 	return body, req, resp, nil
 }
 
-func rewriteHtml(bodyB []byte, u *url.URL, rule Rule) string {
+func rewriteHtml(bodyB []byte, u *url.URL, rule ruleset.Rule) string {
 	// Rewrite the HTML
 	body := string(bodyB)
 
@@ -156,63 +174,11 @@ func getenv(key, fallback string) string {
 	return value
 }
 
-func loadRules() RuleSet {
+func fetchRule(domain string, path string) ruleset.Rule {
-	rulesUrl := os.Getenv("RULESET")
-	if rulesUrl == "" {
-		RulesList := RuleSet{}
-		return RulesList
-	}
-	log.Println("Loading rules")
-
-	var ruleSet RuleSet
-	if strings.HasPrefix(rulesUrl, "http") {
-
-		resp, err := http.Get(rulesUrl)
-		if err != nil {
-			log.Println("ERROR:", err)
-		}
-		defer resp.Body.Close()
-
-		if resp.StatusCode >= 400 {
-			log.Println("ERROR:", resp.StatusCode, rulesUrl)
-		}
-
-		body, err := io.ReadAll(resp.Body)
-		if err != nil {
-			log.Println("ERROR:", err)
-		}
-		yaml.Unmarshal(body, &ruleSet)
-
-		if err != nil {
-			log.Println("ERROR:", err)
-		}
-	} else {
-		yamlFile, err := os.ReadFile(rulesUrl)
-		if err != nil {
-			log.Println("ERROR:", err)
-		}
-		yaml.Unmarshal(yamlFile, &ruleSet)
-	}
-
-	domains := []string{}
-	for _, rule := range ruleSet {
-
-		domains = append(domains, rule.Domain)
-		domains = append(domains, rule.Domains...)
-		if os.Getenv("ALLOWED_DOMAINS_RULESET") == "true" {
-			allowedDomains = append(allowedDomains, domains...)
-		}
-	}
-
-	log.Println("Loaded ", len(ruleSet), " rules for", len(domains), "Domains")
-	return ruleSet
-}
-
-func fetchRule(domain string, path string) Rule {
 	if len(rulesSet) == 0 {
-		return Rule{}
+		return ruleset.Rule{}
 	}
-	rule := Rule{}
+	rule := ruleset.Rule{}
 	for _, rule := range rulesSet {
 		domains := rule.Domains
 		if rule.Domain != "" {
@@ -231,7 +197,7 @@ func fetchRule(domain string, path string) Rule {
 	return rule
 }
 
-func applyRules(body string, rule Rule) string {
+func applyRules(body string, rule ruleset.Rule) string {
 	if len(rulesSet) == 0 {
 		return body
 	}

handlers/proxy.test.go

@@ -2,6 +2,7 @@
 package handlers
 
 import (
+	"ladder/pkg/ruleset"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
@@ -13,7 +14,7 @@ import (
 
 func TestProxySite(t *testing.T) {
 	app := fiber.New()
-	app.Get("/:url", ProxySite)
+	app.Get("/:url", ProxySite(""))
 
 	req := httptest.NewRequest("GET", "/https://example.com", nil)
 	resp, err := app.Test(req)
@@ -51,7 +52,7 @@ func TestRewriteHtml(t *testing.T) {
 		</html>
 	`
 
-	actual := rewriteHtml(bodyB, u, Rule{})
+	actual := rewriteHtml(bodyB, u, ruleset.Rule{})
 	assert.Equal(t, expected, actual)
 }
 

pkg/ruleset/ruleset.go

@@ -0,0 +1,274 @@
+package ruleset
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+
+	"compress/gzip"
+
+	"gopkg.in/yaml.v3"
+)
+
+type Regex struct {
+	Match   string `yaml:"match"`
+	Replace string `yaml:"replace"`
+}
+
+type RuleSet []Rule
+
+type Rule struct {
+	Domain  string   `yaml:"domain,omitempty"`
+	Domains []string `yaml:"domains,omitempty"`
+	Paths   []string `yaml:"paths,omitempty"`
+	Headers struct {
+		UserAgent     string `yaml:"user-agent,omitempty"`
+		XForwardedFor string `yaml:"x-forwarded-for,omitempty"`
+		Referer       string `yaml:"referer,omitempty"`
+		Cookie        string `yaml:"cookie,omitempty"`
+		CSP           string `yaml:"content-security-policy,omitempty"`
+	} `yaml:"headers,omitempty"`
+	GoogleCache bool    `yaml:"googleCache,omitempty"`
+	RegexRules  []Regex `yaml:"regexRules"`
+	Injections  []struct {
+		Position string `yaml:"position"`
+		Append   string `yaml:"append"`
+		Prepend  string `yaml:"prepend"`
+		Replace  string `yaml:"replace"`
+	} `yaml:"injections"`
+}
+
+// NewRulesetFromEnv creates a new RuleSet based on the RULESET environment variable.
+// It logs a warning and returns an empty RuleSet if the RULESET environment variable is not set.
+// If the RULESET is set but the rules cannot be loaded, it panics.
+func NewRulesetFromEnv() RuleSet {
+	rulesPath, ok := os.LookupEnv("RULESET")
+	if !ok {
+		log.Printf("WARN: No ruleset specified. Set the `RULESET` environment variable to load one for a better success rate.")
+		return RuleSet{}
+	}
+	ruleSet, err := NewRuleset(rulesPath)
+	if err != nil {
+		log.Panicln(ruleSet)
+	}
+	return ruleSet
+}
+
+// NewRuleset loads a RuleSet from a given string of rule paths, separated by semicolons.
+// It supports loading rules from both local file paths and remote URLs.
+// Returns a RuleSet and an error if any issues occur during loading.
+func NewRuleset(rulePaths string) (RuleSet, error) {
+	ruleSet := RuleSet{}
+	errs := []error{}
+
+	rp := strings.Split(rulePaths, ";")
+	for _, rule := range rp {
+		rulePath := strings.Trim(rule, " ")
+		var err error
+
+		isRemote, _ := regexp.MatchString(`^https?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()!@:%_\+.~#?&\/\/=]*)`, rulePath)
+		if isRemote {
+			err = ruleSet.loadRulesFromRemoteFile(rulePath)
+		} else {
+			err = ruleSet.loadRulesFromLocalDir(rulePath)
+		}
+
+		if err != nil {
+			e := errors.New(fmt.Sprintf("WARN: failed to load ruleset from ''%s", rulePath))
+			errs = append(errs, errors.Join(e, err))
+			continue
+		}
+	}
+
+	if len(errs) != 0 {
+		e := errors.New(fmt.Sprintf("WARN: failed to load %d rulesets", len(rp)))
+		errs = append(errs, e)
+		// panic if the user specified a local ruleset, but it wasn't found on disk
+		// don't fail silently
+		for _, err := range errs {
+			if errors.Is(os.ErrNotExist, err) {
+				e := fmt.Errorf("PANIC: ruleset '%s' not found", err)
+				panic(errors.Join(e, err))
+			}
+		}
+		// else, bubble up any errors, such as syntax or remote host issues
+		return ruleSet, errors.Join(errs...)
+	}
+	ruleSet.PrintStats()
+	return ruleSet, nil
+}
+
+// ================== RULESET loading logic ===================================
+
+// loadRulesFromLocalDir loads rules from a local directory specified by the path.
+// It walks through the directory, loading rules from YAML files.
+// Returns an error if the directory cannot be accessed
+// If there is an issue loading any file, it will be skipped
+func (rs *RuleSet) loadRulesFromLocalDir(path string) error {
+	_, err := os.Stat(path)
+	if err != nil {
+		return err
+	}
+
+	yamlRegex := regexp.MustCompile(`.*\.ya?ml`)
+
+	err = filepath.Walk(path, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if info.IsDir() {
+			return nil
+		}
+		if isYaml := yamlRegex.MatchString(path); !isYaml {
+			return nil
+		}
+
+		err = rs.loadRulesFromLocalFile(path)
+		if err != nil {
+			log.Printf("WARN: failed to load directory ruleset '%s': %s, skipping", path, err)
+			return nil
+		}
+		log.Printf("INFO: loaded ruleset %s\n", path)
+		return nil
+	})
+
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// loadRulesFromLocalFile loads rules from a local YAML file specified by the path.
+// Returns an error if the file cannot be read or if there's a syntax error in the YAML.
+func (rs *RuleSet) loadRulesFromLocalFile(path string) error {
+	yamlFile, err := os.ReadFile(path)
+	if err != nil {
+		e := errors.New(fmt.Sprintf("failed to read rules from local file: '%s'", path))
+		return errors.Join(e, err)
+	}
+
+	var r RuleSet
+	err = yaml.Unmarshal(yamlFile, &r)
+	if err != nil {
+		e := errors.New(fmt.Sprintf("failed to load rules from local file, possible syntax error in '%s'", path))
+		ee := errors.Join(e, err)
+		if _, ok := os.LookupEnv("DEBUG"); ok {
+			debugPrintRule(string(yamlFile), ee)
+		}
+		return ee
+	}
+	*rs = append(*rs, r...)
+	return nil
+}
+
+// loadRulesFromRemoteFile loads rules from a remote URL.
+// It supports plain and gzip compressed content.
+// Returns an error if there's an issue accessing the URL or if there's a syntax error in the YAML.
+func (rs *RuleSet) loadRulesFromRemoteFile(rulesUrl string) error {
+	var r RuleSet
+	resp, err := http.Get(rulesUrl)
+	if err != nil {
+		e := errors.New(fmt.Sprintf("failed to load rules from remote url '%s'", rulesUrl))
+		return errors.Join(e, err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode >= 400 {
+		e := errors.New(fmt.Sprintf("failed to load rules from remote url (%s) on '%s'", resp.Status, rulesUrl))
+		return errors.Join(e, err)
+	}
+
+	var reader io.Reader
+	isGzip := strings.HasSuffix(rulesUrl, ".gz") || strings.HasSuffix(rulesUrl, ".gzip") || resp.Header.Get("content-encoding") == "gzip"
+
+	if isGzip {
+		reader, err = gzip.NewReader(resp.Body)
+		if err != nil {
+			return fmt.Errorf("failed to create gzip reader for URL '%s' with status code '%s': %w", rulesUrl, resp.Status, err)
+		}
+	} else {
+		reader = resp.Body
+	}
+
+	err = yaml.NewDecoder(reader).Decode(&r)
+
+	if err != nil {
+		e := errors.New(fmt.Sprintf("failed to load rules from remote url '%s' with status code '%s' and possible syntax error", rulesUrl, resp.Status))
+		ee := errors.Join(e, err)
+		return ee
+	}
+
+	*rs = append(*rs, r...)
+	return nil
+}
+
+// ================= utility methods ==========================
+
+// Yaml returns the ruleset as a Yaml string
+func (rs *RuleSet) Yaml() (string, error) {
+	y, err := yaml.Marshal(rs)
+	if err != nil {
+		return "", err
+	}
+	return string(y), nil
+}
+
+// GzipYaml returns an io.Reader that streams the Gzip-compressed YAML representation of the RuleSet.
+func (rs *RuleSet) GzipYaml() (io.Reader, error) {
+	pr, pw := io.Pipe()
+
+	go func() {
+		defer pw.Close()
+
+		gw := gzip.NewWriter(pw)
+		defer gw.Close()
+
+		if err := yaml.NewEncoder(gw).Encode(rs); err != nil {
+			gw.Close() // Ensure to close the gzip writer
+			pw.CloseWithError(err)
+			return
+		}
+	}()
+
+	return pr, nil
+}
+
+// Domains extracts and returns a slice of all domains present in the RuleSet.
+func (rs *RuleSet) Domains() []string {
+	var domains []string
+	for _, rule := range *rs {
+		domains = append(domains, rule.Domain)
+		domains = append(domains, rule.Domains...)
+	}
+	return domains
+}
+
+// DomainCount returns the count of unique domains present in the RuleSet.
+func (rs *RuleSet) DomainCount() int {
+	return len(rs.Domains())
+}
+
+// Count returns the total number of rules in the RuleSet.
+func (rs *RuleSet) Count() int {
+	return len(*rs)
+}
+
+// PrintStats logs the number of rules and domains loaded in the RuleSet.
+func (rs *RuleSet) PrintStats() {
+	log.Printf("INFO: Loaded %d rules for %d domains\n", rs.Count(), rs.DomainCount())
+}
+
+// debugPrintRule is a utility function for printing a rule and associated error for debugging purposes.
+func debugPrintRule(rule string, err error) {
+	fmt.Println("------------------------------ BEGIN DEBUG RULESET -----------------------------")
+	fmt.Printf("%s\n", err.Error())
+	fmt.Println("--------------------------------------------------------------------------------")
+	fmt.Println(rule)
+	fmt.Println("------------------------------ END DEBUG RULESET -------------------------------")
+}

pkg/ruleset/ruleset_test.go

@@ -0,0 +1,153 @@
+package ruleset
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/gofiber/fiber/v2"
+	"github.com/stretchr/testify/assert"
+)
+
+var (
+	validYAML = `
+- domain: example.com
+  regexRules:
+    - match: "^http:"
+      replace: "https:"`
+
+	invalidYAML = `
+- domain: [thisIsATestYamlThatIsMeantToFail.example]
+  regexRules:
+    - match: "^http:"
+      replace: "https:"
+    - match: "[incomplete"`
+)
+
+func TestLoadRulesFromRemoteFile(t *testing.T) {
+	app := fiber.New()
+	defer app.Shutdown()
+
+	app.Get("/valid-config.yml", func(c *fiber.Ctx) error {
+		c.SendString(validYAML)
+		return nil
+	})
+	app.Get("/invalid-config.yml", func(c *fiber.Ctx) error {
+		c.SendString(invalidYAML)
+		return nil
+	})
+
+	app.Get("/valid-config.gz", func(c *fiber.Ctx) error {
+		c.Set("Content-Type", "application/octet-stream")
+		rs, err := loadRuleFromString(validYAML)
+		if err != nil {
+			t.Errorf("failed to load valid yaml from string: %s", err.Error())
+		}
+		s, err := rs.GzipYaml()
+		if err != nil {
+			t.Errorf("failed to load gzip serialize yaml: %s", err.Error())
+		}
+
+		err = c.SendStream(s)
+		if err != nil {
+			t.Errorf("failed to stream gzip serialized yaml: %s", err.Error())
+		}
+		return nil
+	})
+
+	// Start the server in a goroutine
+	go func() {
+		if err := app.Listen("127.0.0.1:9999"); err != nil {
+			t.Errorf("Server failed to start: %s", err.Error())
+		}
+	}()
+
+	// Wait for the server to start
+	time.Sleep(time.Second * 1)
+
+	rs, err := NewRuleset("http://127.0.0.1:9999/valid-config.yml")
+	if err != nil {
+		t.Errorf("failed to load plaintext ruleset from http server: %s", err.Error())
+	}
+	assert.Equal(t, rs[0].Domain, "example.com")
+
+	rs, err = NewRuleset("http://127.0.0.1:9999/valid-config.gz")
+	if err != nil {
+		t.Errorf("failed to load gzipped ruleset from http server: %s", err.Error())
+	}
+	assert.Equal(t, rs[0].Domain, "example.com")
+
+	os.Setenv("RULESET", "http://127.0.0.1:9999/valid-config.gz")
+	rs = NewRulesetFromEnv()
+	if !assert.Equal(t, rs[0].Domain, "example.com") {
+		t.Error("expected no errors loading ruleset from gzip url using environment variable, but got one")
+	}
+}
+
+func loadRuleFromString(yaml string) (RuleSet, error) {
+	// Create a temporary file and load it
+	tmpFile, _ := os.CreateTemp("", "ruleset*.yaml")
+	defer os.Remove(tmpFile.Name())
+	tmpFile.WriteString(yaml)
+	rs := RuleSet{}
+	err := rs.loadRulesFromLocalFile(tmpFile.Name())
+	return rs, err
+}
+
+// TestLoadRulesFromLocalFile tests the loading of rules from a local YAML file.
+func TestLoadRulesFromLocalFile(t *testing.T) {
+	rs, err := loadRuleFromString(validYAML)
+	if err != nil {
+		t.Errorf("Failed to load rules from valid YAML: %s", err)
+	}
+	assert.Equal(t, rs[0].Domain, "example.com")
+	assert.Equal(t, rs[0].RegexRules[0].Match, "^http:")
+	assert.Equal(t, rs[0].RegexRules[0].Replace, "https:")
+
+	_, err = loadRuleFromString(invalidYAML)
+	if err == nil {
+		t.Errorf("Expected an error when loading invalid YAML, but got none")
+	}
+}
+
+// TestLoadRulesFromLocalDir tests the loading of rules from a local nested directory full of yaml rulesets
+func TestLoadRulesFromLocalDir(t *testing.T) {
+	// Create a temporary directory
+	baseDir, err := os.MkdirTemp("", "ruleset_test")
+	if err != nil {
+		t.Fatalf("Failed to create temporary directory: %s", err)
+	}
+	defer os.RemoveAll(baseDir)
+
+	// Create a nested subdirectory
+	nestedDir := filepath.Join(baseDir, "nested")
+	err = os.Mkdir(nestedDir, 0755)
+	if err != nil {
+		t.Fatalf("Failed to create nested directory: %s", err)
+	}
+
+	// Create a nested subdirectory
+	nestedTwiceDir := filepath.Join(nestedDir, "nestedTwice")
+	err = os.Mkdir(nestedTwiceDir, 0755)
+
+	testCases := []string{"test.yaml", "test2.yaml", "test-3.yaml", "test 4.yaml", "1987.test.yaml.yml", "foobar.example.com.yaml", "foobar.com.yml"}
+	for _, fileName := range testCases {
+		filePath := filepath.Join(nestedDir, "2x-"+fileName)
+		os.WriteFile(filePath, []byte(validYAML), 0644)
+		filePath = filepath.Join(nestedDir, fileName)
+		os.WriteFile(filePath, []byte(validYAML), 0644)
+		filePath = filepath.Join(baseDir, "base-"+fileName)
+		os.WriteFile(filePath, []byte(validYAML), 0644)
+	}
+	rs := RuleSet{}
+	err = rs.loadRulesFromLocalDir(baseDir)
+	assert.NoError(t, err)
+	assert.Equal(t, rs.Count(), len(testCases)*3)
+
+	for _, rule := range rs {
+		assert.Equal(t, rule.Domain, "example.com")
+		assert.Equal(t, rule.RegexRules[0].Match, "^http:")
+		assert.Equal(t, rule.RegexRules[0].Replace, "https:")
+	}
+}