20300: Merge similar test cases and fix query cache sensitivity.

[arvados.git] / services / keep-web / handler.go

diff --git a/services/keep-web/handler.go b/services/keep-web/handler.go
index 27981c487de0f1a8c6373c65fd4504bfe0042491..3af326a1ad451483da29bb6398624b508e0d1fe2 100644 (file)
--- a/services/keep-web/handler.go
+++ b/services/keep-web/handler.go
@@ -18,6 +18,7 @@ import (
        "strconv"
        "strings"
        "sync"
+       "time"
 
        "git.arvados.org/arvados.git/lib/cmd"
        "git.arvados.org/arvados.git/lib/webdavfs"
@@ -35,6 +36,10 @@ type handler struct {
        Cache     cache
        Cluster   *arvados.Cluster
        setupOnce sync.Once
+
+       lockMtx    sync.Mutex
+       lock       map[string]*sync.RWMutex
+       lockTidied time.Time
 }
 
 var urlPDHDecoder = strings.NewReplacer(" ", "+", "-", "+")
@@ -182,15 +187,7 @@ func (h *handler) ServeHTTP(wOrig http.ResponseWriter, r *http.Request) {
 
        w := httpserver.WrapResponseWriter(wOrig)
 
-       if method := r.Header.Get("Access-Control-Request-Method"); method != "" && r.Method == "OPTIONS" {
-               if !browserMethod[method] && !webdavMethod[method] {
-                       w.WriteHeader(http.StatusMethodNotAllowed)
-                       return
-               }
-               w.Header().Set("Access-Control-Allow-Headers", corsAllowHeadersHeader)
-               w.Header().Set("Access-Control-Allow-Methods", "COPY, DELETE, GET, LOCK, MKCOL, MOVE, OPTIONS, POST, PROPFIND, PROPPATCH, PUT, RMCOL, UNLOCK")
-               w.Header().Set("Access-Control-Allow-Origin", "*")
-               w.Header().Set("Access-Control-Max-Age", "86400")
+       if r.Method == "OPTIONS" && ServeCORSPreflight(w, r.Header) {
                return
        }
 
@@ -414,16 +411,20 @@ func (h *handler) ServeHTTP(wOrig http.ResponseWriter, r *http.Request) {
                        // collection id is outside scope of supplied
                        // token
                        tokenScopeProblem = true
+                       sess.Release()
                        continue
                } else if os.IsNotExist(err) {
                        // collection does not exist or is not
                        // readable using this token
+                       sess.Release()
                        continue
                } else if err != nil {
                        http.Error(w, err.Error(), http.StatusInternalServerError)
+                       sess.Release()
                        return
                }
                defer f.Close()
+               defer sess.Release()
 
                collectionDir, sessionFS, session, tokenUser = f, fs, sess, user
                break
@@ -538,7 +539,11 @@ func (h *handler) ServeHTTP(wOrig http.ResponseWriter, r *http.Request) {
        }
        h.logUploadOrDownload(r, session.arvadosclient, sessionFS, fsprefix+strings.Join(targetPath, "/"), nil, tokenUser)
 
-       if writeMethod[r.Method] {
+       writing := writeMethod[r.Method]
+       locker := h.collectionLock(collectionID, writing)
+       defer locker.Unlock()
+
+       if writing {
                // Save the collection only if/when all
                // webdav->filesystem operations succeed --
                // and send a 500 error if the modified
@@ -949,3 +954,54 @@ func (h *handler) determineCollection(fs arvados.CustomFileSystem, path string)
        }
        return nil, ""
 }
+
+var lockTidyInterval = time.Minute * 10
+
+// Lock the specified collection for reading or writing. Caller must
+// call Unlock() on the returned Locker when the operation is
+// finished.
+func (h *handler) collectionLock(collectionID string, writing bool) sync.Locker {
+       h.lockMtx.Lock()
+       defer h.lockMtx.Unlock()
+       if time.Since(h.lockTidied) > lockTidyInterval {
+               // Periodically delete all locks that aren't in use.
+               h.lockTidied = time.Now()
+               for id, locker := range h.lock {
+                       if locker.TryLock() {
+                               locker.Unlock()
+                               delete(h.lock, id)
+                       }
+               }
+       }
+       locker := h.lock[collectionID]
+       if locker == nil {
+               locker = new(sync.RWMutex)
+               if h.lock == nil {
+                       h.lock = map[string]*sync.RWMutex{}
+               }
+               h.lock[collectionID] = locker
+       }
+       if writing {
+               locker.Lock()
+               return locker
+       } else {
+               locker.RLock()
+               return locker.RLocker()
+       }
+}
+
+func ServeCORSPreflight(w http.ResponseWriter, header http.Header) bool {
+       method := header.Get("Access-Control-Request-Method")
+       if method == "" {
+               return false
+       }
+       if !browserMethod[method] && !webdavMethod[method] {
+               w.WriteHeader(http.StatusMethodNotAllowed)
+               return true
+       }
+       w.Header().Set("Access-Control-Allow-Headers", corsAllowHeadersHeader)
+       w.Header().Set("Access-Control-Allow-Methods", "COPY, DELETE, GET, LOCK, MKCOL, MOVE, OPTIONS, POST, PROPFIND, PROPPATCH, PUT, RMCOL, UNLOCK")
+       w.Header().Set("Access-Control-Allow-Origin", "*")
+       w.Header().Set("Access-Control-Max-Age", "86400")
+       return true
+}