feat(archive): add concurrency control for archive operations

Introduce a new `archiveWorkers` channel to limit the number of concurrent archive operations. When the limit is reached, new requests will receive a 429 Too Many Requests response. This prevents resource exhaustion and improves system stability. The maximum number of workers can be configured via the `--max-archive-workers` CLI option.

README.md

@@ -28,7 +28,7 @@ Will generate executable file "main" in current directory.
 Start server on port 8080, root directory is current working directory:
 ```sh
 ghfs -l 8080
-``` 
+```
 
 Start server on port 8080, root directory is /usr/share/doc:
 ```sh
@@ -258,7 +258,10 @@ ghfs [options]
 -A|--global-archive
  Allow user to download the whole contents of current directory for all url paths.
  A download link will appear on top part of the page.
- Make sure there is no circular symbol links.
+--max-archive-workers <number>
+ Maximum number of concurrent archive operations.
+ Set to -1 for unlimited (default).
+ When the limit is reached, new archive requests will receive 429 Too Many Requests.
 --archive <url-path> ...
 --archive-user <separator><url-path>[<separator><allowed-username>...] ...
  Allow user to download the whole contents of current directory for specific url paths(and sub paths).
@@ -304,7 +307,7 @@ ghfs [options]
 -S|--show <wildcard> ...
 -SD|--show-dir <wildcard> ...
 -SF|--show-file <wildcard> ...
- If specified, files or directories match wildcards(except hidden by hide option) will be shown. 
+ If specified, files or directories match wildcards(except hidden by hide option) will be shown.
 
 -H|--hide <wildcard> ...
 -HD|--hide-dir <wildcard> ...

src/param/cli.go

@@ -2,12 +2,13 @@ package param
 
 import (
 "errors"
-"mjpclab.dev/ghfs/src/goNixArgParser"
-"mjpclab.dev/ghfs/src/goVirtualHost"
-"mjpclab.dev/ghfs/src/serverError"
 "net/http"
 "os"
 "strings"
+
+"mjpclab.dev/ghfs/src/goNixArgParser"
+"mjpclab.dev/ghfs/src/goVirtualHost"
+"mjpclab.dev/ghfs/src/serverError"
 )
 
 var cliCmd = NewCliCmd()
@@ -147,6 +148,9 @@ func NewCliCmd() *goNixArgParser.Command {
 err = options.AddFlagValues("archivedirsusers", "--archive-dir-user", "", nil, "file system path that allow archive files for specific users, <sep><fs-path>[<sep><user>...]")
 serverError.CheckFatal(err)
 
+err = options.AddFlagValue("maxarchiveworkers", "--max-archive-workers", "", "-1", "maximum number of concurrent archive operations (-1 for unlimited)")
+serverError.CheckFatal(err)
+
 err = options.AddFlag("globalcors", "--global-cors", "GHFS_GLOBAL_CORS", "enable CORS headers for all directories")
 serverError.CheckFatal(err)
 
@@ -436,6 +440,8 @@ func CmdResultsToParams(results []*goNixArgParser.ParseResult) (params Params, e
 archiveDirsUsers, _ := result.GetStrings("archivedirsusers")
 param.ArchiveDirsUsers = SplitAllKeyValues(archiveDirsUsers)
 
+param.ArchiveMaxWorkers, _ = result.GetInt("maxarchiveworkers")
+
 // global restrict access
 if result.HasKey("globalrestrictaccess") {
 param.GlobalRestrictAccess, _ = result.GetStrings("globalrestrictaccess")
@@ -464,7 +470,7 @@ func CmdResultsToParams(results []*goNixArgParser.ParseResult) (params Params, e
 // certificate
 certFiles, _ := result.GetStrings("certs")
 keyFiles, _ := result.GetStrings("keys")
-param.CertKeyPaths, es = goVirtualHost.CertsKeysToPairs(certFiles, keyFiles)
+param.CertKeyPaths, _ = goVirtualHost.CertsKeysToPairs(certFiles, keyFiles)
 
 // listen
 listens, _ := result.GetStrings("listens")

src/param/main.go

@@ -1,11 +1,12 @@
 package param
 
 import (
+"os"
+"path/filepath"
+
 "mjpclab.dev/ghfs/src/middleware"
 "mjpclab.dev/ghfs/src/serverError"
 "mjpclab.dev/ghfs/src/util"
-"os"
-"path/filepath"
 )
 
 type Param struct {
@@ -56,11 +57,13 @@ type Param struct {
 DeleteDirs []string
 DeleteDirsUsers [][]string // [][path, user...]
 
-GlobalArchive bool
-ArchiveUrls []string
-ArchiveUrlsUsers [][]string // [][path, user...]
-ArchiveDirs []string
-ArchiveDirsUsers [][]string // [][path, user...]
+GlobalArchive bool
+ArchiveUrls []string
+ArchiveUrlsUsers [][]string // [][path, user...]
+ArchiveDirs []string
+ArchiveDirsUsers [][]string // [][path, user...]
+ArchiveMaxWorkers int
+ArchivationsSem chan struct{}
 
 GlobalCors bool
 CorsUrls []string
@@ -163,6 +166,10 @@ func (param *Param) Normalize() (errs []error) {
 param.DeleteDirs = NormalizeFsPaths(param.DeleteDirs)
 param.ArchiveUrls = NormalizeUrlPaths(param.ArchiveUrls)
 param.ArchiveDirs = NormalizeFsPaths(param.ArchiveDirs)
+if param.ArchiveMaxWorkers > 0 {
+param.ArchivationsSem = make(chan struct{}, param.ArchiveMaxWorkers)
+}
+
 param.CorsUrls = NormalizeUrlPaths(param.CorsUrls)
 param.CorsDirs = NormalizeFsPaths(param.CorsDirs)
 

src/serverHandler/aliasHandler.go

@@ -1,16 +1,17 @@
 package serverHandler
 
 import (
+"net/http"
+"regexp"
+"strconv"
+"strings"
+
 "mjpclab.dev/ghfs/src/middleware"
 "mjpclab.dev/ghfs/src/param"
 "mjpclab.dev/ghfs/src/serverLog"
 "mjpclab.dev/ghfs/src/tpl/theme"
 "mjpclab.dev/ghfs/src/user"
 "mjpclab.dev/ghfs/src/util"
-"net/http"
-"regexp"
-"strconv"
-"strings"
 )
 
 var defaultHandler = http.NotFoundHandler()
@@ -48,6 +49,8 @@ type aliasHandler struct {
 archive *hierarchyAvailability
 cors *hierarchyAvailability
 
+archiveWorkers chan struct{}
+
 globalRestrictAccess []string
 restrictAccessUrls pathStringsList
 restrictAccessDirs pathStringsList
@@ -120,21 +123,8 @@ func (h *aliasHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
 if session.isMutate && h.mutate(w, r, session, data) {
 return
-} else if session.isArchive {
-switch session.archiveFormat {
-case tarFmt:
-if h.tar(w, r, session, data) {
-return
-}
-case tgzFmt:
-if h.tgz(w, r, session, data) {
-return
-}
-case zipFmt:
-if h.zip(w, r, session, data) {
-return
-}
-}
+} else if session.isArchive && h.createArchive(w, r, session, data) {
+return
 }
 }
 
@@ -152,6 +142,29 @@ func (h *aliasHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 }
 }
 
+func (h *aliasHandler) createArchive(w http.ResponseWriter, r *http.Request, session *sessionContext, data *responseData) bool {
+if h.archiveWorkers != nil {
+select {
+case h.archiveWorkers <- struct{}{}:
+defer func() { <-h.archiveWorkers }()
+default:
+data.Status = http.StatusTooManyRequests
+return false
+}
+}
+
+switch session.archiveFormat {
+case tarFmt:
+return h.tar(w, r, session, data)
+case tgzFmt:
+return h.tgz(w, r, session, data)
+case zipFmt:
+return h.zip(w, r, session, data)
+}
+
+return false
+}
+
 func newAliasHandler(
 p *param.Param,
 vhostCtx *vhostContext,
@@ -179,6 +192,8 @@ func newAliasHandler(
 toHttpsPort: p.ToHttpsPort,
 defaultSort: p.DefaultSort,
 
+archiveWorkers: p.ArchivationsSem,
+
 users: vhostCtx.users,
 theme: vhostCtx.theme,
 logger: vhostCtx.logger,