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package static
import (
"net/http"
"path"
"strings"
"github.com/spiral/errors"
"github.com/spiral/roadrunner/v2/plugins/config"
"github.com/spiral/roadrunner/v2/plugins/logger"
)
// PluginName contains default service name.
const PluginName = "static"
const RootPluginName = "http"
// Plugin serves static files. Potentially convert into middleware?
type Plugin struct {
// server configuration (location, forbidden files and etc)
cfg *Config
log logger.Logger
// root is initiated http directory
root http.Dir
// file extensions which are allowed to be served
allowedExtensions map[string]struct{}
// file extensions which are forbidden to be served
forbiddenExtensions map[string]struct{}
}
// Init must return configure service and return true if service hasStatus enabled. Must return error in case of
// misconfiguration. Services must not be used without proper configuration pushed first.
func (s *Plugin) Init(cfg config.Configurer, log logger.Logger) error {
const op = errors.Op("static_plugin_init")
if !cfg.Has(RootPluginName) {
return errors.E(op, errors.Disabled)
}
err := cfg.UnmarshalKey(RootPluginName, &s.cfg)
if err != nil {
return errors.E(op, errors.Disabled, err)
}
if s.cfg.Static == nil {
return errors.E(op, errors.Disabled)
}
s.log = log
s.root = http.Dir(s.cfg.Static.Dir)
err = s.cfg.Valid()
if err != nil {
return errors.E(op, err)
}
// create 2 hashmaps with the allowed and forbidden file extensions
s.allowedExtensions = make(map[string]struct{}, len(s.cfg.Static.Allow))
s.forbiddenExtensions = make(map[string]struct{}, len(s.cfg.Static.Forbid))
// init forbidden
for i := 0; i < len(s.cfg.Static.Forbid); i++ {
// skip empty lines
if s.cfg.Static.Forbid[i] == "" {
continue
}
s.forbiddenExtensions[s.cfg.Static.Forbid[i]] = struct{}{}
}
// init allowed
for i := 0; i < len(s.cfg.Static.Allow); i++ {
// skip empty lines
if s.cfg.Static.Allow[i] == "" {
continue
}
s.allowedExtensions[s.cfg.Static.Allow[i]] = struct{}{}
}
// check if any forbidden items presented in the allowed
// if presented, delete such items from allowed
for k := range s.forbiddenExtensions {
delete(s.allowedExtensions, k)
}
// at this point we have distinct allowed and forbidden hashmaps, also with alwaysServed
return nil
}
func (s *Plugin) Name() string {
return PluginName
}
// Middleware must return true if request/response pair is handled within the middleware.
func (s *Plugin) Middleware(next http.Handler) http.Handler {
// Define the http.HandlerFunc
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
// do not allow paths like ../../resource
// only specified folder and resources in it
// https://lgtm.com/rules/1510366186013/
if strings.Contains(r.URL.Path, "..") {
w.WriteHeader(http.StatusForbidden)
return
}
if s.cfg.Static.Request != nil {
for k, v := range s.cfg.Static.Request {
r.Header.Add(k, v)
}
}
if s.cfg.Static.Response != nil {
for k, v := range s.cfg.Static.Response {
w.Header().Set(k, v)
}
}
// first - create a proper file path
fPath := path.Clean(r.URL.Path)
ext := strings.ToLower(path.Ext(fPath))
// check that file extension in the forbidden list
if _, ok := s.forbiddenExtensions[ext]; ok {
s.log.Debug("file extension is forbidden", "ext", ext)
next.ServeHTTP(w, r)
return
}
// if we have some allowed extensions, we should check them
// if not - all extensions allowed except forbidden
if len(s.allowedExtensions) > 0 {
// not found in allowed
if _, ok := s.allowedExtensions[ext]; !ok {
next.ServeHTTP(w, r)
return
}
// file extension allowed
}
// ok, file is not in the forbidden list
// Stat it and get file info
f, err := s.root.Open(fPath)
if err != nil {
// else no such file, show error in logs only in debug mode
s.log.Debug("no such file or directory", "error", err)
// pass request to the worker
next.ServeHTTP(w, r)
return
}
// at high confidence there is should not be an error
// because we stat-ed the path previously and know, that that is file (not a dir), and it exists
finfo, err := f.Stat()
if err != nil {
// else no such file, show error in logs only in debug mode
s.log.Debug("no such file or directory", "error", err)
// pass request to the worker
next.ServeHTTP(w, r)
return
}
defer func() {
err = f.Close()
if err != nil {
s.log.Error("file close error", "error", err)
}
}()
// if provided path to the dir, do not serve the dir, but pass the request to the worker
if finfo.IsDir() {
s.log.Debug("possible path to dir provided")
// pass request to the worker
next.ServeHTTP(w, r)
return
}
// set etag
if s.cfg.Static.CalculateEtag {
SetEtag(s.cfg.Static.Weak, f, finfo.Name(), w)
}
// we passed all checks - serve the file
http.ServeContent(w, r, finfo.Name(), finfo.ModTime(), f)
})
}
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