11925: Fix flaky tests in test_computenode_dispatch_slurm.

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

diff --git a/services/keep-web/handler.go b/services/keep-web/handler.go
index ecc698256a2e8d4b3f815f5ba73b92c5077f900f..16df210fe83cc12096549f5609fafeecdcc09340 100644 (file)
--- a/services/keep-web/handler.go
+++ b/services/keep-web/handler.go
@@ -1,3 +1,7 @@
+// Copyright (C) The Arvados Authors. All rights reserved.
+//
+// SPDX-License-Identifier: AGPL-3.0
+
 package main
 
 import (
@@ -17,14 +21,16 @@ import (
        "git.curoverse.com/arvados.git/sdk/go/arvados"
        "git.curoverse.com/arvados.git/sdk/go/arvadosclient"
        "git.curoverse.com/arvados.git/sdk/go/auth"
+       "git.curoverse.com/arvados.git/sdk/go/health"
        "git.curoverse.com/arvados.git/sdk/go/httpserver"
        "git.curoverse.com/arvados.git/sdk/go/keepclient"
 )
 
 type handler struct {
-       Config     *Config
-       clientPool *arvadosclient.ClientPool
-       setupOnce  sync.Once
+       Config        *Config
+       clientPool    *arvadosclient.ClientPool
+       setupOnce     sync.Once
+       healthHandler http.Handler
 }
 
 // parseCollectionIDFromDNSName returns a UUID or PDH if s begins with
@@ -66,7 +72,13 @@ func parseCollectionIDFromURL(s string) string {
 
 func (h *handler) setup() {
        h.clientPool = arvadosclient.MakeClientPool()
+
        keepclient.RefreshServiceDiscoveryOnSIGHUP()
+
+       h.healthHandler = &health.Handler{
+               Token:  h.Config.ManagementToken,
+               Prefix: "/_health/",
+       }
 }
 
 func (h *handler) serveStatus(w http.ResponseWriter, r *http.Request) {
@@ -106,6 +118,11 @@ func (h *handler) ServeHTTP(wOrig http.ResponseWriter, r *http.Request) {
                httpserver.Log(remoteAddr, statusCode, statusText, w.WroteBodyBytes(), r.Method, r.Host, r.URL.Path, r.URL.RawQuery)
        }()
 
+       if strings.HasPrefix(r.URL.Path, "/_health/") && r.Method == "GET" {
+               h.healthHandler.ServeHTTP(w, r)
+               return
+       }
+
        if r.Method == "OPTIONS" {
                method := r.Header.Get("Access-Control-Request-Method")
                if method != "GET" && method != "POST" {
@@ -165,7 +182,7 @@ func (h *handler) ServeHTTP(wOrig http.ResponseWriter, r *http.Request) {
                h.serveStatus(w, r)
                return
        } else if len(pathParts) >= 1 && strings.HasPrefix(pathParts[0], "c=") {
-               // /c=ID/PATH...
+               // /c=ID[/PATH...]
                targetID = parseCollectionIDFromURL(pathParts[0][2:])
                stripParts = 1
        } else if len(pathParts) >= 2 && pathParts[0] == "collections" {
@@ -321,18 +338,30 @@ func (h *handler) ServeHTTP(wOrig http.ResponseWriter, r *http.Request) {
        }, kc)
        openPath := "/" + strings.Join(targetPath, "/")
        if f, err := fs.Open(openPath); os.IsNotExist(err) {
+               // Requested non-existent path
                statusCode = http.StatusNotFound
        } else if err != nil {
+               // Some other (unexpected) error
                statusCode, statusText = http.StatusInternalServerError, err.Error()
        } else if stat, err := f.Stat(); err != nil {
+               // Can't get Size/IsDir (shouldn't happen with a collectionFS!)
                statusCode, statusText = http.StatusInternalServerError, err.Error()
        } else if stat.IsDir() && !strings.HasSuffix(r.URL.Path, "/") {
+               // If client requests ".../dirname", redirect to
+               // ".../dirname/". This way, relative links in the
+               // listing for "dirname" can always be "fnm", never
+               // "dirname/fnm".
                h.seeOtherWithCookie(w, r, basename+"/", credentialsOK)
        } else if stat.IsDir() {
                h.serveDirectory(w, r, collection.Name, fs, openPath, stripParts)
        } else {
                http.ServeContent(w, r, basename, stat.ModTime(), f)
-               if int64(w.WroteBodyBytes()) != stat.Size() {
+               if r.Header.Get("Range") == "" && int64(w.WroteBodyBytes()) != stat.Size() {
+                       // If we wrote fewer bytes than expected, it's
+                       // too late to change the real response code
+                       // or send an error message to the client, but
+                       // at least we can try to put some useful
+                       // debugging info in the logs.
                        n, err := f.Read(make([]byte, 1024))
                        statusCode, statusText = http.StatusInternalServerError, fmt.Sprintf("f.Size()==%d but only wrote %d bytes; read(1024) returns %d, %s", stat.Size(), w.WroteBodyBytes(), n, err)
 
@@ -377,9 +406,13 @@ the entire collection with wget, try:</P>
 
 <H2>File Listing</H2>
 
+{{if .Files}}
 <UL>
 {{range .Files}}  <LI>{{.Size | printf "%15d  " | nbsp}}<A href="{{.Name}}">{{.Name}}</A></LI>{{end}}
 </UL>
+{{else}}
+<P>(No files; this collection is empty.)</P>
+{{end}}
 
 <HR noshade>
 <DIV class="footer">