Merge branch 'master' into 6260-test-datamanager
[arvados.git] / sdk / go / keepclient / keepclient_test.go
index 04be03baa415e3f294b921f7d59d1f65c8bb9ccb..e4e459e83a51c408141c7127a098f69e955a005e 100644 (file)
@@ -1,11 +1,12 @@
 package keepclient
 
 import (
-       "git.curoverse.com/arvados.git/sdk/go/arvadosclient"
-       "git.curoverse.com/arvados.git/sdk/go/streamer"
        "crypto/md5"
        "flag"
        "fmt"
+       "git.curoverse.com/arvados.git/sdk/go/arvadosclient"
+       "git.curoverse.com/arvados.git/sdk/go/arvadostest"
+       "git.curoverse.com/arvados.git/sdk/go/streamer"
        . "gopkg.in/check.v1"
        "io"
        "io/ioutil"
@@ -13,7 +14,6 @@ import (
        "net"
        "net/http"
        "os"
-       "os/exec"
        "testing"
 )
 
@@ -44,64 +44,29 @@ func (s *ServerRequiredSuite) SetUpSuite(c *C) {
                c.Skip("Skipping tests that require server")
                return
        }
-       os.Chdir(pythonDir())
-       {
-               cmd := exec.Command("python", "run_test_server.py", "start")
-               stderr, err := cmd.StderrPipe()
-               if err != nil {
-                       log.Fatalf("Setting up stderr pipe: %s", err)
-               }
-               go io.Copy(os.Stderr, stderr)
-               if err := cmd.Run(); err != nil {
-                       panic(fmt.Sprintf("'python run_test_server.py start' returned error %s", err))
-               }
-       }
-       {
-               cmd := exec.Command("python", "run_test_server.py", "start_keep")
-               stderr, err := cmd.StderrPipe()
-               if err != nil {
-                       log.Fatalf("Setting up stderr pipe: %s", err)
-               }
-               go io.Copy(os.Stderr, stderr)
-               if err := cmd.Run(); err != nil {
-                       panic(fmt.Sprintf("'python run_test_server.py start_keep' returned error %s", err))
-               }
-       }
+       arvadostest.StartAPI()
+       arvadostest.StartKeep()
 }
 
 func (s *ServerRequiredSuite) TearDownSuite(c *C) {
-       os.Chdir(pythonDir())
-       exec.Command("python", "run_test_server.py", "stop_keep").Run()
-       exec.Command("python", "run_test_server.py", "stop").Run()
+       if *no_server {
+               return
+       }
+       arvadostest.StopKeep()
+       arvadostest.StopAPI()
 }
 
 func (s *ServerRequiredSuite) TestMakeKeepClient(c *C) {
-       os.Setenv("ARVADOS_API_HOST", "localhost:3000")
-       os.Setenv("ARVADOS_API_TOKEN", "4axaw8zxe0qm22wa6urpp5nskcne8z88cvbupv653y1njyi05h")
-       os.Setenv("ARVADOS_API_HOST_INSECURE", "true")
-
        arv, err := arvadosclient.MakeArvadosClient()
        c.Assert(err, Equals, nil)
 
        kc, err := MakeKeepClient(&arv)
 
        c.Assert(err, Equals, nil)
-       c.Check(len(kc.ServiceRoots()), Equals, 2)
-       c.Check(kc.ServiceRoots()[0], Equals, "http://localhost:25107")
-       c.Check(kc.ServiceRoots()[1], Equals, "http://localhost:25108")
-}
-
-func (s *StandaloneSuite) TestShuffleServiceRoots(c *C) {
-       kc := KeepClient{}
-       kc.SetServiceRoots([]string{"http://localhost:25107", "http://localhost:25108", "http://localhost:25109", "http://localhost:25110", "http://localhost:25111", "http://localhost:25112", "http://localhost:25113", "http://localhost:25114", "http://localhost:25115", "http://localhost:25116", "http://localhost:25117", "http://localhost:25118", "http://localhost:25119", "http://localhost:25120", "http://localhost:25121", "http://localhost:25122", "http://localhost:25123"})
-
-       // "foo" acbd18db4cc2f85cedef654fccc4a4d8
-       foo_shuffle := []string{"http://localhost:25116", "http://localhost:25120", "http://localhost:25119", "http://localhost:25122", "http://localhost:25108", "http://localhost:25114", "http://localhost:25112", "http://localhost:25107", "http://localhost:25118", "http://localhost:25111", "http://localhost:25113", "http://localhost:25121", "http://localhost:25110", "http://localhost:25117", "http://localhost:25109", "http://localhost:25115", "http://localhost:25123"}
-       c.Check(kc.shuffledServiceRoots("acbd18db4cc2f85cedef654fccc4a4d8"), DeepEquals, foo_shuffle)
-
-       // "bar" 37b51d194a7513e45b56f6524f2d51f2
-       bar_shuffle := []string{"http://localhost:25108", "http://localhost:25112", "http://localhost:25119", "http://localhost:25107", "http://localhost:25110", "http://localhost:25116", "http://localhost:25122", "http://localhost:25120", "http://localhost:25121", "http://localhost:25117", "http://localhost:25111", "http://localhost:25123", "http://localhost:25118", "http://localhost:25113", "http://localhost:25114", "http://localhost:25115", "http://localhost:25109"}
-       c.Check(kc.shuffledServiceRoots("37b51d194a7513e45b56f6524f2d51f2"), DeepEquals, bar_shuffle)
+       c.Check(len(kc.LocalRoots()), Equals, 2)
+       for _, root := range kc.LocalRoots() {
+               c.Check(root, Matches, "http://localhost:\\d+")
+       }
 }
 
 type StubPutHandler struct {
@@ -112,34 +77,32 @@ type StubPutHandler struct {
        handled        chan string
 }
 
-func (this StubPutHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
-       this.c.Check(req.URL.Path, Equals, "/"+this.expectPath)
-       this.c.Check(req.Header.Get("Authorization"), Equals, fmt.Sprintf("OAuth2 %s", this.expectApiToken))
+func (sph StubPutHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
+       sph.c.Check(req.URL.Path, Equals, "/"+sph.expectPath)
+       sph.c.Check(req.Header.Get("Authorization"), Equals, fmt.Sprintf("OAuth2 %s", sph.expectApiToken))
        body, err := ioutil.ReadAll(req.Body)
-       this.c.Check(err, Equals, nil)
-       this.c.Check(body, DeepEquals, []byte(this.expectBody))
+       sph.c.Check(err, Equals, nil)
+       sph.c.Check(body, DeepEquals, []byte(sph.expectBody))
        resp.WriteHeader(200)
-       this.handled <- fmt.Sprintf("http://%s", req.Host)
+       sph.handled <- fmt.Sprintf("http://%s", req.Host)
 }
 
-func RunBogusKeepServer(st http.Handler, port int) (listener net.Listener, url string) {
+func RunFakeKeepServer(st http.Handler) (ks KeepServer) {
        var err error
-       listener, err = net.ListenTCP("tcp", &net.TCPAddr{Port: port})
+       ks.listener, err = net.ListenTCP("tcp", &net.TCPAddr{Port: 0})
        if err != nil {
-               panic(fmt.Sprintf("Could not listen on tcp port %v", port))
+               panic(fmt.Sprintf("Could not listen on any port"))
        }
-
-       url = fmt.Sprintf("http://localhost:%d", port)
-
-       go http.Serve(listener, st)
-       return listener, url
+       ks.url = fmt.Sprintf("http://%s", ks.listener.Addr().String())
+       go http.Serve(ks.listener, st)
+       return
 }
 
-func UploadToStubHelper(c *C, st http.Handler, f func(KeepClient, string,
+func UploadToStubHelper(c *C, st http.Handler, f func(*KeepClient, string,
        io.ReadCloser, io.WriteCloser, chan uploadStatus)) {
 
-       listener, url := RunBogusKeepServer(st, 2990)
-       defer listener.Close()
+       ks := RunFakeKeepServer(st)
+       defer ks.listener.Close()
 
        arv, _ := arvadosclient.MakeArvadosClient()
        arv.ApiToken = "abc123"
@@ -149,7 +112,7 @@ func UploadToStubHelper(c *C, st http.Handler, f func(KeepClient, string,
        reader, writer := io.Pipe()
        upload_status := make(chan uploadStatus)
 
-       f(kc, url, reader, writer, upload_status)
+       f(kc, ks.url, reader, writer, upload_status)
 }
 
 func (s *StandaloneSuite) TestUploadToStubKeepServer(c *C) {
@@ -163,10 +126,10 @@ func (s *StandaloneSuite) TestUploadToStubKeepServer(c *C) {
                make(chan string)}
 
        UploadToStubHelper(c, st,
-               func(kc KeepClient, url string, reader io.ReadCloser,
+               func(kc *KeepClient, url string, reader io.ReadCloser,
                        writer io.WriteCloser, upload_status chan uploadStatus) {
 
-                       go kc.uploadToKeepServer(url, st.expectPath, reader, upload_status, int64(len("foo")))
+                       go kc.uploadToKeepServer(url, st.expectPath, reader, upload_status, int64(len("foo")), "TestUploadToStubKeepServer")
 
                        writer.Write([]byte("foo"))
                        writer.Close()
@@ -190,7 +153,7 @@ func (s *StandaloneSuite) TestUploadToStubKeepServerBufferReader(c *C) {
                make(chan string)}
 
        UploadToStubHelper(c, st,
-               func(kc KeepClient, url string, reader io.ReadCloser,
+               func(kc *KeepClient, url string, reader io.ReadCloser,
                        writer io.WriteCloser, upload_status chan uploadStatus) {
 
                        tr := streamer.AsyncStreamFromReader(512, reader)
@@ -198,7 +161,7 @@ func (s *StandaloneSuite) TestUploadToStubKeepServerBufferReader(c *C) {
 
                        br1 := tr.MakeStreamReader()
 
-                       go kc.uploadToKeepServer(url, st.expectPath, br1, upload_status, 3)
+                       go kc.uploadToKeepServer(url, st.expectPath, br1, upload_status, 3, "TestUploadToStubKeepServerBufferReader")
 
                        writer.Write([]byte("foo"))
                        writer.Close()
@@ -216,9 +179,9 @@ type FailHandler struct {
        handled chan string
 }
 
-func (this FailHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
+func (fh FailHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
        resp.WriteHeader(500)
-       this.handled <- fmt.Sprintf("http://%s", req.Host)
+       fh.handled <- fmt.Sprintf("http://%s", req.Host)
 }
 
 func (s *StandaloneSuite) TestFailedUploadToStubKeepServer(c *C) {
@@ -230,10 +193,10 @@ func (s *StandaloneSuite) TestFailedUploadToStubKeepServer(c *C) {
        hash := "acbd18db4cc2f85cedef654fccc4a4d8"
 
        UploadToStubHelper(c, st,
-               func(kc KeepClient, url string, reader io.ReadCloser,
+               func(kc *KeepClient, url string, reader io.ReadCloser,
                        writer io.WriteCloser, upload_status chan uploadStatus) {
 
-                       go kc.uploadToKeepServer(url, hash, reader, upload_status, 3)
+                       go kc.uploadToKeepServer(url, hash, reader, upload_status, 3, "TestFailedUploadToStubKeepServer")
 
                        writer.Write([]byte("foo"))
                        writer.Close()
@@ -252,12 +215,11 @@ type KeepServer struct {
        url      string
 }
 
-func RunSomeFakeKeepServers(st http.Handler, n int, port int) (ks []KeepServer) {
+func RunSomeFakeKeepServers(st http.Handler, n int) (ks []KeepServer) {
        ks = make([]KeepServer, n)
 
        for i := 0; i < n; i += 1 {
-               boguslistener, bogusurl := RunBogusKeepServer(st, port+i)
-               ks[i] = KeepServer{boguslistener, bogusurl}
+               ks[i] = RunFakeKeepServer(st)
        }
 
        return ks
@@ -266,34 +228,37 @@ func RunSomeFakeKeepServers(st http.Handler, n int, port int) (ks []KeepServer)
 func (s *StandaloneSuite) TestPutB(c *C) {
        log.Printf("TestPutB")
 
-       hash := fmt.Sprintf("%x", md5.Sum([]byte("foo")))
+       hash := Md5String("foo")
 
        st := StubPutHandler{
                c,
                hash,
                "abc123",
                "foo",
-               make(chan string, 2)}
+               make(chan string, 5)}
 
        arv, _ := arvadosclient.MakeArvadosClient()
        kc, _ := MakeKeepClient(&arv)
 
        kc.Want_replicas = 2
        arv.ApiToken = "abc123"
-       service_roots := make([]string, 5)
+       localRoots := make(map[string]string)
+       writableLocalRoots := make(map[string]string)
 
-       ks := RunSomeFakeKeepServers(st, 5, 2990)
+       ks := RunSomeFakeKeepServers(st, 5)
 
-       for i := 0; i < len(ks); i += 1 {
-               service_roots[i] = ks[i].url
-               defer ks[i].listener.Close()
+       for i, k := range ks {
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               writableLocalRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               defer k.listener.Close()
        }
 
-       kc.SetServiceRoots(service_roots)
+       kc.SetServiceRoots(localRoots, writableLocalRoots, nil)
 
        kc.PutB([]byte("foo"))
 
-       shuff := kc.shuffledServiceRoots(fmt.Sprintf("%x", md5.Sum([]byte("foo"))))
+       shuff := NewRootSorter(
+               kc.LocalRoots(), Md5String("foo")).GetSortedRoots()
 
        s1 := <-st.handled
        s2 := <-st.handled
@@ -315,23 +280,25 @@ func (s *StandaloneSuite) TestPutHR(c *C) {
                hash,
                "abc123",
                "foo",
-               make(chan string, 2)}
+               make(chan string, 5)}
 
        arv, _ := arvadosclient.MakeArvadosClient()
        kc, _ := MakeKeepClient(&arv)
 
        kc.Want_replicas = 2
        arv.ApiToken = "abc123"
-       service_roots := make([]string, 5)
+       localRoots := make(map[string]string)
+       writableLocalRoots := make(map[string]string)
 
-       ks := RunSomeFakeKeepServers(st, 5, 2990)
+       ks := RunSomeFakeKeepServers(st, 5)
 
-       for i := 0; i < len(ks); i += 1 {
-               service_roots[i] = ks[i].url
-               defer ks[i].listener.Close()
+       for i, k := range ks {
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               writableLocalRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               defer k.listener.Close()
        }
 
-       kc.SetServiceRoots(service_roots)
+       kc.SetServiceRoots(localRoots, writableLocalRoots, nil)
 
        reader, writer := io.Pipe()
 
@@ -342,7 +309,7 @@ func (s *StandaloneSuite) TestPutHR(c *C) {
 
        kc.PutHR(hash, reader, 3)
 
-       shuff := kc.shuffledServiceRoots(hash)
+       shuff := NewRootSorter(kc.LocalRoots(), hash).GetSortedRoots()
        log.Print(shuff)
 
        s1 := <-st.handled
@@ -366,7 +333,7 @@ func (s *StandaloneSuite) TestPutWithFail(c *C) {
                hash,
                "abc123",
                "foo",
-               make(chan string, 2)}
+               make(chan string, 4)}
 
        fh := FailHandler{
                make(chan string, 1)}
@@ -376,23 +343,27 @@ func (s *StandaloneSuite) TestPutWithFail(c *C) {
 
        kc.Want_replicas = 2
        arv.ApiToken = "abc123"
-       service_roots := make([]string, 5)
+       localRoots := make(map[string]string)
+       writableLocalRoots := make(map[string]string)
 
-       ks1 := RunSomeFakeKeepServers(st, 4, 2990)
-       ks2 := RunSomeFakeKeepServers(fh, 1, 2995)
+       ks1 := RunSomeFakeKeepServers(st, 4)
+       ks2 := RunSomeFakeKeepServers(fh, 1)
 
        for i, k := range ks1 {
-               service_roots[i] = k.url
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               writableLocalRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
                defer k.listener.Close()
        }
        for i, k := range ks2 {
-               service_roots[len(ks1)+i] = k.url
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i+len(ks1))] = k.url
+               writableLocalRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i+len(ks1))] = k.url
                defer k.listener.Close()
        }
 
-       kc.SetServiceRoots(service_roots)
+       kc.SetServiceRoots(localRoots, writableLocalRoots, nil)
 
-       shuff := kc.shuffledServiceRoots(fmt.Sprintf("%x", md5.Sum([]byte("foo"))))
+       shuff := NewRootSorter(
+               kc.LocalRoots(), Md5String("foo")).GetSortedRoots()
 
        phash, replicas, err := kc.PutB([]byte("foo"))
 
@@ -401,8 +372,14 @@ func (s *StandaloneSuite) TestPutWithFail(c *C) {
        c.Check(err, Equals, nil)
        c.Check(phash, Equals, "")
        c.Check(replicas, Equals, 2)
-       c.Check(<-st.handled, Equals, shuff[1])
-       c.Check(<-st.handled, Equals, shuff[2])
+
+       s1 := <-st.handled
+       s2 := <-st.handled
+
+       c.Check((s1 == shuff[1] && s2 == shuff[2]) ||
+               (s1 == shuff[2] && s2 == shuff[1]),
+               Equals,
+               true)
 }
 
 func (s *StandaloneSuite) TestPutWithTooManyFail(c *C) {
@@ -425,29 +402,30 @@ func (s *StandaloneSuite) TestPutWithTooManyFail(c *C) {
 
        kc.Want_replicas = 2
        arv.ApiToken = "abc123"
-       service_roots := make([]string, 5)
+       localRoots := make(map[string]string)
+       writableLocalRoots := make(map[string]string)
 
-       ks1 := RunSomeFakeKeepServers(st, 1, 2990)
-       ks2 := RunSomeFakeKeepServers(fh, 4, 2991)
+       ks1 := RunSomeFakeKeepServers(st, 1)
+       ks2 := RunSomeFakeKeepServers(fh, 4)
 
        for i, k := range ks1 {
-               service_roots[i] = k.url
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               writableLocalRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
                defer k.listener.Close()
        }
        for i, k := range ks2 {
-               service_roots[len(ks1)+i] = k.url
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i+len(ks1))] = k.url
+               writableLocalRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i+len(ks1))] = k.url
                defer k.listener.Close()
        }
 
-       kc.SetServiceRoots(service_roots)
-
-       shuff := kc.shuffledServiceRoots(fmt.Sprintf("%x", md5.Sum([]byte("foo"))))
+       kc.SetServiceRoots(localRoots, writableLocalRoots, nil)
 
        _, replicas, err := kc.PutB([]byte("foo"))
 
        c.Check(err, Equals, InsufficientReplicasError)
        c.Check(replicas, Equals, 1)
-       c.Check(<-st.handled, Equals, shuff[1])
+       c.Check(<-st.handled, Equals, ks1[0].url)
 
        log.Printf("TestPutWithTooManyFail done")
 }
@@ -456,14 +434,16 @@ type StubGetHandler struct {
        c              *C
        expectPath     string
        expectApiToken string
-       returnBody     []byte
+       httpStatus     int
+       body           []byte
 }
 
-func (this StubGetHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
-       this.c.Check(req.URL.Path, Equals, "/"+this.expectPath)
-       this.c.Check(req.Header.Get("Authorization"), Equals, fmt.Sprintf("OAuth2 %s", this.expectApiToken))
-       resp.Header().Set("Content-Length", fmt.Sprintf("%d", len(this.returnBody)))
-       resp.Write(this.returnBody)
+func (sgh StubGetHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) {
+       sgh.c.Check(req.URL.Path, Equals, "/"+sgh.expectPath)
+       sgh.c.Check(req.Header.Get("Authorization"), Equals, fmt.Sprintf("OAuth2 %s", sgh.expectApiToken))
+       resp.WriteHeader(sgh.httpStatus)
+       resp.Header().Set("Content-Length", fmt.Sprintf("%d", len(sgh.body)))
+       resp.Write(sgh.body)
 }
 
 func (s *StandaloneSuite) TestGet(c *C) {
@@ -475,21 +455,22 @@ func (s *StandaloneSuite) TestGet(c *C) {
                c,
                hash,
                "abc123",
+               http.StatusOK,
                []byte("foo")}
 
-       listener, url := RunBogusKeepServer(st, 2990)
-       defer listener.Close()
+       ks := RunFakeKeepServer(st)
+       defer ks.listener.Close()
 
        arv, err := arvadosclient.MakeArvadosClient()
        kc, _ := MakeKeepClient(&arv)
        arv.ApiToken = "abc123"
-       kc.SetServiceRoots([]string{url})
+       kc.SetServiceRoots(map[string]string{"x": ks.url}, map[string]string{ks.url: ""}, nil)
 
        r, n, url2, err := kc.Get(hash)
        defer r.Close()
        c.Check(err, Equals, nil)
        c.Check(n, Equals, int64(3))
-       c.Check(url2, Equals, fmt.Sprintf("%s/%s", url, hash))
+       c.Check(url2, Equals, fmt.Sprintf("%s/%s", ks.url, hash))
 
        content, err2 := ioutil.ReadAll(r)
        c.Check(err2, Equals, nil)
@@ -503,13 +484,13 @@ func (s *StandaloneSuite) TestGetFail(c *C) {
 
        st := FailHandler{make(chan string, 1)}
 
-       listener, url := RunBogusKeepServer(st, 2990)
-       defer listener.Close()
+       ks := RunFakeKeepServer(st)
+       defer ks.listener.Close()
 
        arv, err := arvadosclient.MakeArvadosClient()
        kc, _ := MakeKeepClient(&arv)
        arv.ApiToken = "abc123"
-       kc.SetServiceRoots([]string{url})
+       kc.SetServiceRoots(map[string]string{"x": ks.url}, map[string]string{ks.url: ""}, nil)
 
        r, n, url2, err := kc.Get(hash)
        c.Check(err, Equals, BlockNotFound)
@@ -518,6 +499,140 @@ func (s *StandaloneSuite) TestGetFail(c *C) {
        c.Check(r, Equals, nil)
 }
 
+func (s *StandaloneSuite) TestGetWithServiceHint(c *C) {
+       uuid := "zzzzz-bi6l4-123451234512345"
+       hash := fmt.Sprintf("%x", md5.Sum([]byte("foo")))
+
+       // This one shouldn't be used:
+       ks0 := RunFakeKeepServer(StubGetHandler{
+               c,
+               "error if used",
+               "abc123",
+               http.StatusOK,
+               []byte("foo")})
+       defer ks0.listener.Close()
+       // This one should be used:
+       ks := RunFakeKeepServer(StubGetHandler{
+               c,
+               hash + "+K@" + uuid,
+               "abc123",
+               http.StatusOK,
+               []byte("foo")})
+       defer ks.listener.Close()
+
+       arv, err := arvadosclient.MakeArvadosClient()
+       kc, _ := MakeKeepClient(&arv)
+       arv.ApiToken = "abc123"
+       kc.SetServiceRoots(
+               map[string]string{"x": ks0.url},
+               map[string]string{"x": ks0.url},
+               map[string]string{uuid: ks.url})
+
+       r, n, uri, err := kc.Get(hash + "+K@" + uuid)
+       defer r.Close()
+       c.Check(err, Equals, nil)
+       c.Check(n, Equals, int64(3))
+       c.Check(uri, Equals, fmt.Sprintf("%s/%s", ks.url, hash+"+K@"+uuid))
+
+       content, err := ioutil.ReadAll(r)
+       c.Check(err, Equals, nil)
+       c.Check(content, DeepEquals, []byte("foo"))
+}
+
+// Use a service hint to fetch from a local disk service, overriding
+// rendezvous probe order.
+func (s *StandaloneSuite) TestGetWithLocalServiceHint(c *C) {
+       uuid := "zzzzz-bi6l4-zzzzzzzzzzzzzzz"
+       hash := fmt.Sprintf("%x", md5.Sum([]byte("foo")))
+
+       // This one shouldn't be used, although it appears first in
+       // rendezvous probe order:
+       ks0 := RunFakeKeepServer(StubGetHandler{
+               c,
+               "error if used",
+               "abc123",
+               http.StatusOK,
+               []byte("foo")})
+       defer ks0.listener.Close()
+       // This one should be used:
+       ks := RunFakeKeepServer(StubGetHandler{
+               c,
+               hash + "+K@" + uuid,
+               "abc123",
+               http.StatusOK,
+               []byte("foo")})
+       defer ks.listener.Close()
+
+       arv, err := arvadosclient.MakeArvadosClient()
+       kc, _ := MakeKeepClient(&arv)
+       arv.ApiToken = "abc123"
+       kc.SetServiceRoots(
+               map[string]string{
+                       "zzzzz-bi6l4-yyyyyyyyyyyyyyy": ks0.url,
+                       "zzzzz-bi6l4-xxxxxxxxxxxxxxx": ks0.url,
+                       "zzzzz-bi6l4-wwwwwwwwwwwwwww": ks0.url,
+                       uuid: ks.url},
+               map[string]string{
+                       "zzzzz-bi6l4-yyyyyyyyyyyyyyy": ks0.url,
+                       "zzzzz-bi6l4-xxxxxxxxxxxxxxx": ks0.url,
+                       "zzzzz-bi6l4-wwwwwwwwwwwwwww": ks0.url,
+                       uuid: ks.url},
+               map[string]string{
+                       "zzzzz-bi6l4-yyyyyyyyyyyyyyy": ks0.url,
+                       "zzzzz-bi6l4-xxxxxxxxxxxxxxx": ks0.url,
+                       "zzzzz-bi6l4-wwwwwwwwwwwwwww": ks0.url,
+                       uuid: ks.url},
+       )
+
+       r, n, uri, err := kc.Get(hash + "+K@" + uuid)
+       defer r.Close()
+       c.Check(err, Equals, nil)
+       c.Check(n, Equals, int64(3))
+       c.Check(uri, Equals, fmt.Sprintf("%s/%s", ks.url, hash+"+K@"+uuid))
+
+       content, err := ioutil.ReadAll(r)
+       c.Check(err, Equals, nil)
+       c.Check(content, DeepEquals, []byte("foo"))
+}
+
+func (s *StandaloneSuite) TestGetWithServiceHintFailoverToLocals(c *C) {
+       uuid := "zzzzz-bi6l4-123451234512345"
+       hash := fmt.Sprintf("%x", md5.Sum([]byte("foo")))
+
+       ksLocal := RunFakeKeepServer(StubGetHandler{
+               c,
+               hash + "+K@" + uuid,
+               "abc123",
+               http.StatusOK,
+               []byte("foo")})
+       defer ksLocal.listener.Close()
+       ksGateway := RunFakeKeepServer(StubGetHandler{
+               c,
+               hash + "+K@" + uuid,
+               "abc123",
+               http.StatusInternalServerError,
+               []byte("Error")})
+       defer ksGateway.listener.Close()
+
+       arv, err := arvadosclient.MakeArvadosClient()
+       kc, _ := MakeKeepClient(&arv)
+       arv.ApiToken = "abc123"
+       kc.SetServiceRoots(
+               map[string]string{"zzzzz-bi6l4-keepdisk0000000": ksLocal.url},
+               map[string]string{"zzzzz-bi6l4-keepdisk0000000": ksLocal.url},
+               map[string]string{uuid: ksGateway.url})
+
+       r, n, uri, err := kc.Get(hash + "+K@" + uuid)
+       c.Assert(err, Equals, nil)
+       defer r.Close()
+       c.Check(n, Equals, int64(3))
+       c.Check(uri, Equals, fmt.Sprintf("%s/%s", ksLocal.url, hash+"+K@"+uuid))
+
+       content, err := ioutil.ReadAll(r)
+       c.Check(err, Equals, nil)
+       c.Check(content, DeepEquals, []byte("foo"))
+}
+
 type BarHandler struct {
        handled chan string
 }
@@ -533,13 +648,13 @@ func (s *StandaloneSuite) TestChecksum(c *C) {
 
        st := BarHandler{make(chan string, 1)}
 
-       listener, url := RunBogusKeepServer(st, 2990)
-       defer listener.Close()
+       ks := RunFakeKeepServer(st)
+       defer ks.listener.Close()
 
        arv, err := arvadosclient.MakeArvadosClient()
        kc, _ := MakeKeepClient(&arv)
        arv.ApiToken = "abc123"
-       kc.SetServiceRoots([]string{url})
+       kc.SetServiceRoots(map[string]string{"x": ks.url}, map[string]string{ks.url: ""}, nil)
 
        r, n, _, err := kc.Get(barhash)
        _, err = ioutil.ReadAll(r)
@@ -557,58 +672,69 @@ func (s *StandaloneSuite) TestChecksum(c *C) {
 }
 
 func (s *StandaloneSuite) TestGetWithFailures(c *C) {
-
-       hash := fmt.Sprintf("%x", md5.Sum([]byte("foo")))
+       content := []byte("waz")
+       hash := fmt.Sprintf("%x", md5.Sum(content))
 
        fh := FailHandler{
-               make(chan string, 1)}
+               make(chan string, 4)}
 
        st := StubGetHandler{
                c,
                hash,
                "abc123",
-               []byte("foo")}
+               http.StatusOK,
+               content}
 
        arv, err := arvadosclient.MakeArvadosClient()
        kc, _ := MakeKeepClient(&arv)
        arv.ApiToken = "abc123"
-       service_roots := make([]string, 5)
+       localRoots := make(map[string]string)
+       writableLocalRoots := make(map[string]string)
 
-       ks1 := RunSomeFakeKeepServers(st, 1, 2990)
-       ks2 := RunSomeFakeKeepServers(fh, 4, 2991)
+       ks1 := RunSomeFakeKeepServers(st, 1)
+       ks2 := RunSomeFakeKeepServers(fh, 4)
 
        for i, k := range ks1 {
-               service_roots[i] = k.url
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               writableLocalRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
                defer k.listener.Close()
        }
        for i, k := range ks2 {
-               service_roots[len(ks1)+i] = k.url
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i+len(ks1))] = k.url
+               writableLocalRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i+len(ks1))] = k.url
                defer k.listener.Close()
        }
 
-       kc.SetServiceRoots(service_roots)
+       kc.SetServiceRoots(localRoots, writableLocalRoots, nil)
+
+       // This test works only if one of the failing services is
+       // attempted before the succeeding service. Otherwise,
+       // <-fh.handled below will just hang! (Probe order depends on
+       // the choice of block content "waz" and the UUIDs of the fake
+       // servers, so we just tried different strings until we found
+       // an example that passes this Assert.)
+       c.Assert(NewRootSorter(localRoots, hash).GetSortedRoots()[0], Not(Equals), ks1[0].url)
 
        r, n, url2, err := kc.Get(hash)
+
        <-fh.handled
        c.Check(err, Equals, nil)
        c.Check(n, Equals, int64(3))
        c.Check(url2, Equals, fmt.Sprintf("%s/%s", ks1[0].url, hash))
 
-       content, err2 := ioutil.ReadAll(r)
+       read_content, err2 := ioutil.ReadAll(r)
        c.Check(err2, Equals, nil)
-       c.Check(content, DeepEquals, []byte("foo"))
+       c.Check(read_content, DeepEquals, content)
 }
 
 func (s *ServerRequiredSuite) TestPutGetHead(c *C) {
-       os.Setenv("ARVADOS_API_HOST", "localhost:3000")
-       os.Setenv("ARVADOS_API_TOKEN", "4axaw8zxe0qm22wa6urpp5nskcne8z88cvbupv653y1njyi05h")
-       os.Setenv("ARVADOS_API_HOST_INSECURE", "true")
+       content := []byte("TestPutGetHead")
 
        arv, err := arvadosclient.MakeArvadosClient()
        kc, err := MakeKeepClient(&arv)
        c.Assert(err, Equals, nil)
 
-       hash := fmt.Sprintf("%x", md5.Sum([]byte("foo")))
+       hash := fmt.Sprintf("%x", md5.Sum(content))
 
        {
                n, _, err := kc.Ask(hash)
@@ -616,26 +742,26 @@ func (s *ServerRequiredSuite) TestPutGetHead(c *C) {
                c.Check(n, Equals, int64(0))
        }
        {
-               hash2, replicas, err := kc.PutB([]byte("foo"))
-               c.Check(hash2, Equals, fmt.Sprintf("%s+%v", hash, 3))
+               hash2, replicas, err := kc.PutB(content)
+               c.Check(hash2, Matches, fmt.Sprintf(`%s\+%d\b.*`, hash, len(content)))
                c.Check(replicas, Equals, 2)
                c.Check(err, Equals, nil)
        }
        {
                r, n, url2, err := kc.Get(hash)
                c.Check(err, Equals, nil)
-               c.Check(n, Equals, int64(3))
-               c.Check(url2, Equals, fmt.Sprintf("http://localhost:25108/%s", hash))
+               c.Check(n, Equals, int64(len(content)))
+               c.Check(url2, Matches, fmt.Sprintf("http://localhost:\\d+/%s", hash))
 
-               content, err2 := ioutil.ReadAll(r)
+               read_content, err2 := ioutil.ReadAll(r)
                c.Check(err2, Equals, nil)
-               c.Check(content, DeepEquals, []byte("foo"))
+               c.Check(read_content, DeepEquals, content)
        }
        {
                n, url2, err := kc.Ask(hash)
                c.Check(err, Equals, nil)
-               c.Check(n, Equals, int64(3))
-               c.Check(url2, Equals, fmt.Sprintf("http://localhost:25108/%s", hash))
+               c.Check(n, Equals, int64(len(content)))
+               c.Check(url2, Matches, fmt.Sprintf("http://localhost:\\d+/%s", hash))
        }
 }
 
@@ -659,16 +785,18 @@ func (s *StandaloneSuite) TestPutProxy(c *C) {
        kc.Want_replicas = 2
        kc.Using_proxy = true
        arv.ApiToken = "abc123"
-       service_roots := make([]string, 1)
+       localRoots := make(map[string]string)
+       writableLocalRoots := make(map[string]string)
 
-       ks1 := RunSomeFakeKeepServers(st, 1, 2990)
+       ks1 := RunSomeFakeKeepServers(st, 1)
 
        for i, k := range ks1 {
-               service_roots[i] = k.url
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               writableLocalRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
                defer k.listener.Close()
        }
 
-       kc.SetServiceRoots(service_roots)
+       kc.SetServiceRoots(localRoots, writableLocalRoots, nil)
 
        _, replicas, err := kc.PutB([]byte("foo"))
        <-st.handled
@@ -690,15 +818,17 @@ func (s *StandaloneSuite) TestPutProxyInsufficientReplicas(c *C) {
        kc.Want_replicas = 3
        kc.Using_proxy = true
        arv.ApiToken = "abc123"
-       service_roots := make([]string, 1)
+       localRoots := make(map[string]string)
+       writableLocalRoots := make(map[string]string)
 
-       ks1 := RunSomeFakeKeepServers(st, 1, 2990)
+       ks1 := RunSomeFakeKeepServers(st, 1)
 
        for i, k := range ks1 {
-               service_roots[i] = k.url
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               writableLocalRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
                defer k.listener.Close()
        }
-       kc.SetServiceRoots(service_roots)
+       kc.SetServiceRoots(localRoots, writableLocalRoots, nil)
 
        _, replicas, err := kc.PutB([]byte("foo"))
        <-st.handled
@@ -710,10 +840,111 @@ func (s *StandaloneSuite) TestPutProxyInsufficientReplicas(c *C) {
 }
 
 func (s *StandaloneSuite) TestMakeLocator(c *C) {
-       l := MakeLocator("91f372a266fe2bf2823cb8ec7fda31ce+3+Aabcde@12345678")
+       l, err := MakeLocator("91f372a266fe2bf2823cb8ec7fda31ce+3+Aabcde@12345678")
+       c.Check(err, Equals, nil)
+       c.Check(l.Hash, Equals, "91f372a266fe2bf2823cb8ec7fda31ce")
+       c.Check(l.Size, Equals, 3)
+       c.Check(l.Hints, DeepEquals, []string{"3", "Aabcde@12345678"})
+}
+
+func (s *StandaloneSuite) TestMakeLocatorNoHints(c *C) {
+       l, err := MakeLocator("91f372a266fe2bf2823cb8ec7fda31ce")
+       c.Check(err, Equals, nil)
+       c.Check(l.Hash, Equals, "91f372a266fe2bf2823cb8ec7fda31ce")
+       c.Check(l.Size, Equals, -1)
+       c.Check(l.Hints, DeepEquals, []string{})
+}
 
+func (s *StandaloneSuite) TestMakeLocatorNoSizeHint(c *C) {
+       l, err := MakeLocator("91f372a266fe2bf2823cb8ec7fda31ce+Aabcde@12345678")
+       c.Check(err, Equals, nil)
+       c.Check(l.Hash, Equals, "91f372a266fe2bf2823cb8ec7fda31ce")
+       c.Check(l.Size, Equals, -1)
+       c.Check(l.Hints, DeepEquals, []string{"Aabcde@12345678"})
+}
+
+func (s *StandaloneSuite) TestMakeLocatorPreservesUnrecognizedHints(c *C) {
+       str := "91f372a266fe2bf2823cb8ec7fda31ce+3+Unknown+Kzzzzz+Afoobar"
+       l, err := MakeLocator(str)
+       c.Check(err, Equals, nil)
        c.Check(l.Hash, Equals, "91f372a266fe2bf2823cb8ec7fda31ce")
        c.Check(l.Size, Equals, 3)
-       c.Check(l.Signature, Equals, "abcde")
-       c.Check(l.Timestamp, Equals, "12345678")
+       c.Check(l.Hints, DeepEquals, []string{"3", "Unknown", "Kzzzzz", "Afoobar"})
+       c.Check(l.String(), Equals, str)
+}
+
+func (s *StandaloneSuite) TestMakeLocatorInvalidInput(c *C) {
+       _, err := MakeLocator("91f372a266fe2bf2823cb8ec7fda31c")
+       c.Check(err, Equals, InvalidLocatorError)
+}
+
+func (s *StandaloneSuite) TestPutBWant2ReplicasWithOnlyOneWritableLocalRoot(c *C) {
+       hash := Md5String("foo")
+
+       st := StubPutHandler{
+               c,
+               hash,
+               "abc123",
+               "foo",
+               make(chan string, 5)}
+
+       arv, _ := arvadosclient.MakeArvadosClient()
+       kc, _ := MakeKeepClient(&arv)
+
+       kc.Want_replicas = 2
+       arv.ApiToken = "abc123"
+       localRoots := make(map[string]string)
+       writableLocalRoots := make(map[string]string)
+
+       ks := RunSomeFakeKeepServers(st, 5)
+
+       for i, k := range ks {
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               if i == 0 {
+                       writableLocalRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               }
+               defer k.listener.Close()
+       }
+
+       kc.SetServiceRoots(localRoots, writableLocalRoots, nil)
+
+       _, replicas, err := kc.PutB([]byte("foo"))
+
+       c.Check(err, Equals, InsufficientReplicasError)
+       c.Check(replicas, Equals, 1)
+
+       c.Check(<-st.handled, Equals, localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", 0)])
+}
+
+func (s *StandaloneSuite) TestPutBWithNoWritableLocalRoots(c *C) {
+       hash := Md5String("foo")
+
+       st := StubPutHandler{
+               c,
+               hash,
+               "abc123",
+               "foo",
+               make(chan string, 5)}
+
+       arv, _ := arvadosclient.MakeArvadosClient()
+       kc, _ := MakeKeepClient(&arv)
+
+       kc.Want_replicas = 2
+       arv.ApiToken = "abc123"
+       localRoots := make(map[string]string)
+       writableLocalRoots := make(map[string]string)
+
+       ks := RunSomeFakeKeepServers(st, 5)
+
+       for i, k := range ks {
+               localRoots[fmt.Sprintf("zzzzz-bi6l4-fakefakefake%03d", i)] = k.url
+               defer k.listener.Close()
+       }
+
+       kc.SetServiceRoots(localRoots, writableLocalRoots, nil)
+
+       _, replicas, err := kc.PutB([]byte("foo"))
+
+       c.Check(err, Equals, InsufficientReplicasError)
+       c.Check(replicas, Equals, 0)
 }