Added load balancer (wip)

+ Added support for multiple upstreams
+ Added load balancer
+ Added upstream abstraction in endpoint
+ Added load balancer structure
+ Added breaking change auto-updater
+ Added uptime monitor proxy type definitions
+ Added upstream editor UI
+ Fixed charset bug in many snippets HTML files

src/mod/update/update.go

@@ -0,0 +1,44 @@
+package update
+
+/*
+	Update.go
+
+	This module handle cross version updates that contains breaking changes
+	update command should always exit after the update is completed
+*/
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+
+	v308 "imuslab.com/zoraxy/mod/update/v308"
+)
+
+// Run config update. Version numbers are int. For example
+// to update 3.0.7 to 3.0.8, use RunConfigUpdate(307, 308)
+// This function support cross versions updates (e.g. 307 -> 310)
+func RunConfigUpdate(fromVersion int, toVersion int) {
+	for i := fromVersion; i < toVersion; i++ {
+		oldVersion := fromVersion
+		newVersion := fromVersion + 1
+		fmt.Println("Updating from v", oldVersion, " to v", newVersion)
+		runUpdateRoutineWithVersion(oldVersion, newVersion)
+	}
+	fmt.Println("Update completed")
+}
+
+func GetVersionIntFromVersionNumber(version string) int {
+	versionNumberOnly := strings.ReplaceAll(version, ".", "")
+	versionInt, _ := strconv.Atoi(versionNumberOnly)
+	return versionInt
+}
+
+func runUpdateRoutineWithVersion(fromVersion int, toVersion int) {
+	if fromVersion == 307 && toVersion == 308 {
+		err := v308.UpdateFrom307To308()
+		if err != nil {
+			panic(err)
+		}
+	}
+}

src/mod/update/v308/typedef307.go

@@ -0,0 +1,138 @@
+package v308
+
+/*
+	v307 type definations
+
+	This file wrap up the self-contained data structure
+	for v3.0.7 structure and allow automatic updates
+	for future releases if required
+*/
+
+type v307PermissionsPolicy struct {
+	Accelerometer              []string `json:"accelerometer"`
+	AmbientLightSensor         []string `json:"ambient_light_sensor"`
+	Autoplay                   []string `json:"autoplay"`
+	Battery                    []string `json:"battery"`
+	Camera                     []string `json:"camera"`
+	CrossOriginIsolated        []string `json:"cross_origin_isolated"`
+	DisplayCapture             []string `json:"display_capture"`
+	DocumentDomain             []string `json:"document_domain"`
+	EncryptedMedia             []string `json:"encrypted_media"`
+	ExecutionWhileNotRendered  []string `json:"execution_while_not_rendered"`
+	ExecutionWhileOutOfView    []string `json:"execution_while_out_of_viewport"`
+	Fullscreen                 []string `json:"fullscreen"`
+	Geolocation                []string `json:"geolocation"`
+	Gyroscope                  []string `json:"gyroscope"`
+	KeyboardMap                []string `json:"keyboard_map"`
+	Magnetometer               []string `json:"magnetometer"`
+	Microphone                 []string `json:"microphone"`
+	Midi                       []string `json:"midi"`
+	NavigationOverride         []string `json:"navigation_override"`
+	Payment                    []string `json:"payment"`
+	PictureInPicture           []string `json:"picture_in_picture"`
+	PublicKeyCredentialsGet    []string `json:"publickey_credentials_get"`
+	ScreenWakeLock             []string `json:"screen_wake_lock"`
+	SyncXHR                    []string `json:"sync_xhr"`
+	USB                        []string `json:"usb"`
+	WebShare                   []string `json:"web_share"`
+	XRSpatialTracking          []string `json:"xr_spatial_tracking"`
+	ClipboardRead              []string `json:"clipboard_read"`
+	ClipboardWrite             []string `json:"clipboard_write"`
+	Gamepad                    []string `json:"gamepad"`
+	SpeakerSelection           []string `json:"speaker_selection"`
+	ConversionMeasurement      []string `json:"conversion_measurement"`
+	FocusWithoutUserActivation []string `json:"focus_without_user_activation"`
+	HID                        []string `json:"hid"`
+	IdleDetection              []string `json:"idle_detection"`
+	InterestCohort             []string `json:"interest_cohort"`
+	Serial                     []string `json:"serial"`
+	SyncScript                 []string `json:"sync_script"`
+	TrustTokenRedemption       []string `json:"trust_token_redemption"`
+	Unload                     []string `json:"unload"`
+	WindowPlacement            []string `json:"window_placement"`
+	VerticalScroll             []string `json:"vertical_scroll"`
+}
+
+// Auth credential for basic auth on certain endpoints
+type v307BasicAuthCredentials struct {
+	Username     string
+	PasswordHash string
+}
+
+// Auth credential for basic auth on certain endpoints
+type v307BasicAuthUnhashedCredentials struct {
+	Username string
+	Password string
+}
+
+// Paths to exclude in basic auth enabled proxy handler
+type v307BasicAuthExceptionRule struct {
+	PathPrefix string
+}
+
+// Header injection direction type
+type v307HeaderDirection int
+
+const (
+	HeaderDirection_ZoraxyToUpstream   v307HeaderDirection = 0 //Inject (or remove) header to request out-going from Zoraxy to backend server
+	HeaderDirection_ZoraxyToDownstream v307HeaderDirection = 1 //Inject (or remove) header to request out-going from Zoraxy to client (e.g. browser)
+)
+
+// User defined headers to add into a proxy endpoint
+type v307UserDefinedHeader struct {
+	Direction v307HeaderDirection
+	Key       string
+	Value     string
+	IsRemove  bool //Instead of set, remove this key instead
+}
+
+// The original proxy endpoint structure from v3.0.7
+type v307ProxyEndpoint struct {
+	ProxyType            int      //The type of this proxy, see const def
+	RootOrMatchingDomain string   //Matching domain for host, also act as key
+	MatchingDomainAlias  []string //A list of domains that alias to this rule
+	Domain               string   //Domain or IP to proxy to
+
+	//TLS/SSL Related
+	RequireTLS               bool //Target domain require TLS
+	BypassGlobalTLS          bool //Bypass global TLS setting options if TLS Listener enabled (parent.tlsListener != nil)
+	SkipCertValidations      bool //Set to true to accept self signed certs
+	SkipWebSocketOriginCheck bool //Skip origin check on websocket upgrade connections
+
+	//Virtual Directories
+	VirtualDirectories []*v307VirtualDirectoryEndpoint
+
+	//Custom Headers
+	UserDefinedHeaders           []*v307UserDefinedHeader //Custom headers to append when proxying requests from this endpoint
+	HSTSMaxAge                   int64                    //HSTS max age, set to 0 for disable HSTS headers
+	EnablePermissionPolicyHeader bool                     //Enable injection of permission policy header
+	PermissionPolicy             *v307PermissionsPolicy   //Permission policy header
+
+	//Authentication
+	RequireBasicAuth        bool                          //Set to true to request basic auth before proxy
+	BasicAuthCredentials    []*v307BasicAuthCredentials   //Basic auth credentials
+	BasicAuthExceptionRules []*v307BasicAuthExceptionRule //Path to exclude in a basic auth enabled proxy target
+
+	// Rate Limiting
+	RequireRateLimit bool
+	RateLimit        int64 // Rate limit in requests per second
+
+	//Access Control
+	AccessFilterUUID string //Access filter ID
+
+	Disabled bool //If the rule is disabled
+
+	//Fallback routing logic (Special Rule Sets Only)
+	DefaultSiteOption int    //Fallback routing logic options
+	DefaultSiteValue  string //Fallback routing target, optional
+}
+
+// A Virtual Directory endpoint, provide a subset of ProxyEndpoint for better
+// program structure than directly using ProxyEndpoint
+type v307VirtualDirectoryEndpoint struct {
+	MatchingPath        string //Matching prefix of the request path, also act as key
+	Domain              string //Domain or IP to proxy to
+	RequireTLS          bool   //Target domain require TLS
+	SkipCertValidations bool   //Set to true to accept self signed certs
+	Disabled            bool   //If the rule is enabled
+}

src/mod/update/v308/typedef308.go

@@ -0,0 +1,63 @@
+package v308
+
+/*
+	v308 type definations
+
+	This file wrap up the self-contained data structure
+	for v3.0.8 structure and allow automatic updates
+	for future releases if required
+
+	Some struct are identical as v307 and hence it is not redefined here
+*/
+
+/* Upstream or Origin Server */
+type v308Upstream struct {
+	//Upstream Proxy Configs
+	OriginIpOrDomain         string //Target IP address or domain name with port
+	RequireTLS               bool   //Require TLS connection
+	SkipCertValidations      bool   //Set to true to accept self signed certs
+	SkipWebSocketOriginCheck bool   //Skip origin check on websocket upgrade connections
+
+	//Load balancing configs
+	Weight  int //Prirotiy of fallback, set all to 0 for round robin
+	MaxConn int //Maxmium connection to this server
+}
+
+// A proxy endpoint record, a general interface for handling inbound routing
+type v308ProxyEndpoint struct {
+	ProxyType            int             //The type of this proxy, see const def
+	RootOrMatchingDomain string          //Matching domain for host, also act as key
+	MatchingDomainAlias  []string        //A list of domains that alias to this rule
+	ActiveOrigins        []*v308Upstream //Activated Upstream or origin servers IP or domain to proxy to
+	InactiveOrigins      []*v308Upstream //Disabled Upstream or origin servers IP or domain to proxy to
+	UseStickySession     bool            //Use stick session for load balancing
+	Disabled             bool            //If the rule is disabled
+
+	//Inbound TLS/SSL Related
+	BypassGlobalTLS bool //Bypass global TLS setting options if TLS Listener enabled (parent.tlsListener != nil)
+
+	//Virtual Directories
+	VirtualDirectories []*v307VirtualDirectoryEndpoint
+
+	//Custom Headers
+	UserDefinedHeaders           []*v307UserDefinedHeader //Custom headers to append when proxying requests from this endpoint
+	HSTSMaxAge                   int64                    //HSTS max age, set to 0 for disable HSTS headers
+	EnablePermissionPolicyHeader bool                     //Enable injection of permission policy header
+	PermissionPolicy             *v307PermissionsPolicy   //Permission policy header
+
+	//Authentication
+	RequireBasicAuth        bool                          //Set to true to request basic auth before proxy
+	BasicAuthCredentials    []*v307BasicAuthCredentials   //Basic auth credentials
+	BasicAuthExceptionRules []*v307BasicAuthExceptionRule //Path to exclude in a basic auth enabled proxy target
+
+	// Rate Limiting
+	RequireRateLimit bool
+	RateLimit        int64 // Rate limit in requests per second
+
+	//Access Control
+	AccessFilterUUID string //Access filter ID
+
+	//Fallback routing logic (Special Rule Sets Only)
+	DefaultSiteOption int    //Fallback routing logic options
+	DefaultSiteValue  string //Fallback routing target, optional
+}

src/mod/update/v308/v308.go

@@ -0,0 +1,132 @@
+package v308
+
+import (
+	"encoding/json"
+	"io"
+	"log"
+	"os"
+	"path/filepath"
+)
+
+/*
+
+	v3.0.7 update to v3.0.8
+
+	This update function
+*/
+
+// Update proxy config files from v3.0.7 to v3.0.8
+func UpdateFrom307To308() error {
+
+	//Load the configs
+	oldConfigFiles, err := filepath.Glob("./conf/proxy/*.config")
+	if err != nil {
+		return err
+	}
+
+	//Backup all the files
+	err = os.MkdirAll("./conf/proxy.old/", 0775)
+	if err != nil {
+		return err
+	}
+
+	for _, oldConfigFile := range oldConfigFiles {
+		// Extract the file name from the path
+		fileName := filepath.Base(oldConfigFile)
+		// Construct the backup file path
+		backupFile := filepath.Join("./conf/proxy.old/", fileName)
+
+		// Copy the file to the backup directory
+		err := copyFile(oldConfigFile, backupFile)
+		if err != nil {
+			return err
+		}
+	}
+
+	//read the config into the old struct
+	for _, oldConfigFile := range oldConfigFiles {
+		configContent, err := os.ReadFile(oldConfigFile)
+		if err != nil {
+			log.Println("Unable to read config file "+filepath.Base(oldConfigFile), err.Error())
+			continue
+		}
+
+		thisOldConfigStruct := v307ProxyEndpoint{}
+		err = json.Unmarshal(configContent, &thisOldConfigStruct)
+		if err != nil {
+			log.Println("Unable to parse file "+filepath.Base(oldConfigFile), err.Error())
+			continue
+		}
+
+		//Convert the old config to new config
+		newProxyStructure := convertV307ToV308(thisOldConfigStruct)
+		js, _ := json.MarshalIndent(newProxyStructure, "", "    ")
+		err = os.WriteFile(oldConfigFile, js, 0775)
+		if err != nil {
+			log.Println(err.Error())
+			continue
+		}
+	}
+
+	return nil
+}
+
+func convertV307ToV308(old v307ProxyEndpoint) v308ProxyEndpoint {
+	// Create a new v308ProxyEndpoint instance
+
+	matchingDomainsSlice := old.MatchingDomainAlias
+	if matchingDomainsSlice == nil {
+		matchingDomainsSlice = []string{}
+	}
+
+	newEndpoint := v308ProxyEndpoint{
+		ProxyType:            old.ProxyType,
+		RootOrMatchingDomain: old.RootOrMatchingDomain,
+		MatchingDomainAlias:  matchingDomainsSlice,
+		ActiveOrigins: []*v308Upstream{{ // Mapping Domain field to v308Upstream struct
+			OriginIpOrDomain:         old.Domain,
+			RequireTLS:               old.RequireTLS,
+			SkipCertValidations:      old.SkipCertValidations,
+			SkipWebSocketOriginCheck: old.SkipWebSocketOriginCheck,
+			Weight:                   1,
+			MaxConn:                  0,
+		}},
+		InactiveOrigins:              []*v308Upstream{},
+		UseStickySession:             false,
+		Disabled:                     old.Disabled,
+		BypassGlobalTLS:              old.BypassGlobalTLS,
+		VirtualDirectories:           old.VirtualDirectories,
+		UserDefinedHeaders:           old.UserDefinedHeaders,
+		HSTSMaxAge:                   old.HSTSMaxAge,
+		EnablePermissionPolicyHeader: old.EnablePermissionPolicyHeader,
+		PermissionPolicy:             old.PermissionPolicy,
+		RequireBasicAuth:             old.RequireBasicAuth,
+		BasicAuthCredentials:         old.BasicAuthCredentials,
+		BasicAuthExceptionRules:      old.BasicAuthExceptionRules,
+		RequireRateLimit:             old.RequireRateLimit,
+		RateLimit:                    old.RateLimit,
+		AccessFilterUUID:             old.AccessFilterUUID,
+		DefaultSiteOption:            old.DefaultSiteOption,
+		DefaultSiteValue:             old.DefaultSiteValue,
+	}
+
+	return newEndpoint
+}
+
+// Helper function to copy files
+func copyFile(src, dst string) error {
+	sourceFile, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer sourceFile.Close()
+
+	destinationFile, err := os.Create(dst)
+	if err != nil {
+		return err
+	}
+	defer destinationFile.Close()
+
+	_, err = io.Copy(destinationFile, sourceFile)
+	return err
+}