rpc/grpcclientidentity: remove hard-coded deadline in listener adatper causing crash

Verified once again that grpc.DialContext is indeed non-blocking.
However, it checks in a defer stmt that the passed dial is not ctx.Done().
That is highly unusual if the dial is non-blocking.
But it might still happen, maybe because of machine suspend during the function call and before the defer stmt is executed.

panic:
context deadline exceeded
goroutine 49 [running]:
github.com/zrepl/zrepl/rpc/grpcclientidentity/grpchelper.ClientConn(0x1906ea0, 0xc0003ea1e0, 0x1921620, 0xc0002da660, 0x0)
        /gopath/src/github.com/zrepl/zrepl/rpc/grpcclientidentity/grpchelper/authlistener_grpc_adaptor_wrapper.go:49 +0x38c
github.com/zrepl/zrepl/rpc.NewClient(0x1906f00, 0xc0002d60f0, 0x1921620, 0xc0002da640, 0x1921620, 0xc0002da660, 0x1921620, 0xc0002da6a0, 0x1921620)
        /gopath/src/github.com/zrepl/zrepl/rpc/rpc_client.go:53 +0x199
github.com/zrepl/zrepl/daemon/job.(*modePush).ConnectEndpoints(0xc0000d1e90, 0x1921620, 0xc0002da640, 0x1921620, 0xc0002da660, 0x1921620, 0xc0002da6a0, 0x1906f00, 0xc0002d60f0)
        /gopath/src/github.com/zrepl/zrepl/daemon/job/active.go:105 +0x15d
github.com/zrepl/zrepl/daemon/job.(*ActiveSide).do(0xc0000d6120, 0x1918720, 0xc00020f170)
        /gopath/src/github.com/zrepl/zrepl/daemon/job/active.go:356 +0x236
github.com/zrepl/zrepl/daemon/job.(*ActiveSide).Run(0xc0000d6120, 0x1918720, 0xc00009c660)
        /gopath/src/github.com/zrepl/zrepl/daemon/job/active.go:347 +0x289
github.com/zrepl/zrepl/daemon.(*jobs).start.func1(0xc0000fc880, 0x1921620, 0xc0002da120, 0x191a320, 0xc0000d6120, 0x1918720, 0xc0002d6a80)

config/samples/local.yml

@@ -26,7 +26,6 @@ jobs:
       - type: last_n
         count: 10
       keep_receiver:
-      - type: most_recent_common_snapshot
       - type: grid
         grid: 1x1h(keep=all) | 24x1h | 35x1d | 6x30d
         regex: "zrepl_.*"

dist/systemd/zrepl.service

@@ -21,8 +21,10 @@ RestrictRealtime=yes
 SystemCallArchitectures=native
 
 # BEGIN ProtectHome
-ProtectHome=read-only   # DEBIAN STRETCH
-# ProtectHome=tmpfs     # FEDORA 28 / 29
+# DEBIAN STRETCH
+ProtectHome=read-only
+# FEDORA 28 / 29
+# ProtectHome=tmpfs
 # END ProtectHome
 
 # BEGIN SystemCallFilter

docs/installation.rst

@@ -37,6 +37,9 @@ The following list may be incomplete, feel free to submit a PR with an update:
     * - MacOS
       - ``brew install zrepl``
       - Available on `homebrew <https://brew.sh>`_
+    * - Arch Linux
+      - ``yay install zrepl-bin``
+      - Available on `AUR <https://aur.archlinux.org/packages/zrepl-bin>`_
     * - Others
       -
       - Use `binary releases`_ or build from source.

pruning/keep_most_recent_common_ancestor.go

@@ -1,29 +0,0 @@
-package pruning
-
-import "sort"
-
-type KeepMostRecentCommonAncestor struct {
-	_opaque struct{}
-}
-
-func NewKeepMostRecentCommonAncestor() *KeepMostRecentCommonAncestor {
-	return &KeepMostRecentCommonAncestor{}
-}
-
-func (k *KeepMostRecentCommonAncestor) KeepRule(snaps []Snapshot) (destroyList []Snapshot) {
-	var bothSides []Snapshot
-	for _, s := range snaps {
-		if s.PresentOnBothSides() {
-			bothSides = append(bothSides, s)
-		}
-	}
-	if len(bothSides) == 0 {
-		return []Snapshot{}
-	}
-
-	sort.Slice(bothSides, func(i, j int) bool {
-		return bothSides[i].Date().After(bothSides[j].Date())
-	})
-
-	return []Snapshot{bothSides[0]}
-}

pruning/keep_most_recent_common_ancestor_test.go

@@ -1,31 +0,0 @@
-package pruning
-
-import "testing"
-
-func TestKeppMostRecentCommonAncestor(t *testing.T) {
-
-	o := func(minutes int) time.Time {
-		return time.Unix(123, 0).Add(time.Duration(minutes) * time.Minute)
-	}
-
-	tcs := map[string]testCase{
-		"empty": {
-			inputs:     []Snapshot{},
-			rules:      []KeepRule{NewKeepMostRecentCommonAncestor()},
-			expDestroy: map[string]bool{},
-		},
-		"nil": {
-			inputs:     nil,
-			rules:      []KeepRule{NewKeepMostRecentCommonAncestor()},
-			expDestroy: map[string]bool{},
-		},
-		"": {
-			inputs: []Snapshot{
-				stubSnap{name: "s1", date: o(5), bothSides: }
-			},
-		}
-	}
-
-	testTable(tcs, t)
-
-}

pruning/pruning.go

@@ -17,7 +17,6 @@ type Snapshot interface {
 	Name() string
 	Replicated() bool
 	Date() time.Time
-	PresentOnBothSides() bool
 }
 
 // The returned snapshot list is guaranteed to only contains elements of input parameter snaps

pruning/pruning_test.go

@@ -9,7 +9,6 @@ type stubSnap struct {
 	name       string
 	replicated bool
 	date       time.Time
-	bothSides bool
 }
 
 func (s stubSnap) Name() string { return s.name }

rpc/grpcclientidentity/grpchelper/authlistener_grpc_adaptor_wrapper.go

@@ -36,9 +36,7 @@ func ClientConn(cn transport.Connecter, log Logger) *grpc.ClientConn {
 	})
 	dialerOption := grpc.WithDialer(grpcclientidentity.NewDialer(log, cn))
 	cred := grpc.WithTransportCredentials(grpcclientidentity.NewTransportCredentials(log))
-	ctx, cancel := context.WithTimeout(context.TODO(), 5*time.Second) // FIXME constant
-	defer cancel()
-	cc, err := grpc.DialContext(ctx, "doesn't matter done by dialer", dialerOption, cred, ka)
+	cc, err := grpc.DialContext(context.Background(), "doesn't matter done by dialer", dialerOption, cred, ka)
 	if err != nil {
 		log.WithError(err).Error("cannot create gRPC client conn (non-blocking)")
 		// It's ok to panic here: the we call grpc.DialContext without the