Add Go CI.

.github/workflows/go.yml

@@ -0,0 +1,90 @@
+name: Go
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+  schedule:
+    - cron: "0 0 * * *"
+
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        go: ['1.16', '1.17', '1.18', '1.x']
+    steps:
+
+    - name: Set up Go ${{ matrix.go }}
+      uses: actions/setup-go@v2
+      with:
+        go-version: ${{ matrix.go }}
+      id: go
+
+    - name: Check out code into the Go module directory
+      uses: actions/checkout@v2
+
+    - name: Get dependencies
+      run: |
+        go get -v -t -d ./...
+
+    - name: Build
+      run: go build -v ./...
+
+    - name: Test
+      run: go test -v -coverprofile=profile.cov ./...
+
+  static_analysis:
+    name: Static Analysis
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.x'
+        id: go
+
+      - name: Install required static analysis tools
+        run: |
+          go install honnef.co/go/tools/cmd/staticcheck@latest
+
+      - name: Check out code
+        uses: actions/checkout@v2
+
+      - name: Go vet
+        run: go vet -composites=false ./...
+
+      - name: Check gofmt
+        run: diff -u <(echo -n) <(gofmt -d -s .)
+
+      - name: Staticcheck
+        run: |
+          staticcheck ./...
+
+  coverage:
+    name: Submit coverage
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: '1.x'
+        id: go
+
+      - name: Install required static analysis tools
+        run: |
+          go install honnef.co/go/tools/cmd/staticcheck@latest
+
+      - name: Check out code
+        uses: actions/checkout@v2
+
+      - name: Test
+        run: go test -v -coverprofile=profile.cov ./...
+
+      - name: Submit coverage
+        uses: shogo82148/actions-goveralls@v1
+        with:
+          path-to-profile: profile.cov

cache/cache.go

@@ -43,6 +43,10 @@ import (
 // int64 (nanoseconds since epoch).
 func T(n int64) time.Time { return time.Unix(0, n) }
 
+// Now is a function that can be overridden in tests to alter the timestamps
+// applied to deletes and metadata updates.
+var Now = time.Now
+
 // A Target hosts an indexed cache of state for a single target.
 type Target struct {
 	name   string             // name of the target
@@ -502,28 +506,49 @@ func (t *Target) gnmiUpdate(n *pb.Notification) (*ctree.Leaf, error) {
 	return t.t.GetLeaf(path), nil
 }
 
+func toDeleteNotification(n *pb.Notification, timestamp int64) *pb.Notification {
+	d := &pb.Notification{
+		Timestamp: timestamp,
+		Prefix: &pb.Path{
+			Target: n.GetPrefix().GetTarget(),
+			Origin: n.GetPrefix().GetOrigin(),
+		},
+	}
+	prefix := n.GetPrefix()
+	path := n.Update[0].GetPath()
+	// Set origin if the origin is in the update
+	if origin := path.GetOrigin(); n.GetPrefix().GetOrigin() == "" && origin != "" {
+		d.Prefix.Origin = origin
+	}
+	switch {
+	case n.GetAtomic():
+		d.Delete = []*pb.Path{{Elem: prefix.GetElem(), Element: prefix.GetElement()}}
+	case len(prefix.GetElem()) > 0 || len(path.GetElem()) > 0:
+		d.Delete = []*pb.Path{{Elem: append(prefix.GetElem(), path.GetElem()...)}}
+	default:
+		d.Delete = []*pb.Path{{Element: append(prefix.GetElement(), path.GetElement()...)}}
+	}
+	return d
+}
+
 func (t *Target) gnmiRemove(n *pb.Notification) []*ctree.Leaf {
 	path := joinPrefixAndPath(n.Prefix, n.Delete[0])
 	if path[0] == metadata.Root {
 		t.meta.ResetEntry(path[1])
 	}
-	leaves := t.t.DeleteConditional(path, func(v interface{}) bool { return v.(*pb.Notification).GetTimestamp() < n.GetTimestamp() })
+	var leaves []*ctree.Leaf
+	f := func(v interface{}) {
+		d := v.(*pb.Notification)
+		leaves = append(leaves, ctree.DetachedLeaf(toDeleteNotification(d, n.GetTimestamp())))
+	}
+	t.t.WalkDeleted(path, func(v interface{}) bool { return v.(*pb.Notification).GetTimestamp() < n.GetTimestamp() }, f)
 	if len(leaves) == 0 {
 		return nil
 	}
 	deleted := int64(len(leaves))
 	t.meta.AddInt(metadata.LeafCount, -deleted)
 	t.meta.AddInt(metadata.DelCount, deleted)
-	var ls []*ctree.Leaf
-	for _, l := range leaves {
-		noti := &pb.Notification{
-			Timestamp: n.GetTimestamp(),
-			Prefix:    &pb.Path{Target: n.GetPrefix().GetTarget()},
-			Delete:    []*pb.Path{{Element: l}},
-		}
-		ls = append(ls, ctree.DetachedLeaf(noti))
-	}
-	return ls
+	return leaves
 }
 
 // updateCache calls fn for each Target.
@@ -645,7 +670,7 @@ func deleteNoti(t, o string, p []string) *pb.Notification {
 		pe = append(pe, &pb.PathElem{Name: e})
 	}
 	return &pb.Notification{
-		Timestamp: time.Now().UnixNano(),
+		Timestamp: Now().UnixNano(),
 		Prefix:    &pb.Path{Target: t, Origin: o},
 		Delete:    []*pb.Path{&pb.Path{Elem: pe}},
 	}
@@ -658,7 +683,7 @@ func metaNoti(t, m string, v *pb.TypedValue) *pb.Notification {
 		pe = append(pe, &pb.PathElem{Name: p})
 	}
 	return &pb.Notification{
-		Timestamp: time.Now().UnixNano(),
+		Timestamp: Now().UnixNano(),
 		Prefix:    &pb.Path{Target: t},
 		Update: []*pb.Update{
 			&pb.Update{