feat: initial tracing support (#1623)

1 files changed, 74 insertions, 0 deletions

diff --git a/vendor/google.golang.org/grpc/internal/resolver/unix/unix.go b/vendor/google.golang.org/grpc/internal/resolver/unix/unix.go
new file mode 100644
index 000000000..160911687
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/resolver/unix/unix.go
@@ -0,0 +1,74 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package unix implements a resolver for unix targets.
+package unix
+
+import (
+	"fmt"
+
+	"google.golang.org/grpc/internal/transport/networktype"
+	"google.golang.org/grpc/resolver"
+)
+
+const unixScheme = "unix"
+const unixAbstractScheme = "unix-abstract"
+
+type builder struct {
+	scheme string
+}
+
+func (b *builder) Build(target resolver.Target, cc resolver.ClientConn, _ resolver.BuildOptions) (resolver.Resolver, error) {
+	if target.URL.Host != "" {
+		return nil, fmt.Errorf("invalid (non-empty) authority: %v", target.URL.Host)
+	}
+
+	// gRPC was parsing the dial target manually before PR #4817, and we
+	// switched to using url.Parse() in that PR. To avoid breaking existing
+	// resolver implementations we ended up stripping the leading "/" from the
+	// endpoint. This obviously does not work for the "unix" scheme. Hence we
+	// end up using the parsed URL instead.
+	endpoint := target.URL.Path
+	if endpoint == "" {
+		endpoint = target.URL.Opaque
+	}
+	addr := resolver.Address{Addr: endpoint}
+	if b.scheme == unixAbstractScheme {
+		// We can not prepend \0 as c++ gRPC does, as in Golang '@' is used to signify we do
+		// not want trailing \0 in address.
+		addr.Addr = "@" + addr.Addr
+	}
+	cc.UpdateState(resolver.State{Addresses: []resolver.Address{networktype.Set(addr, "unix")}})
+	return &nopResolver{}, nil
+}
+
+func (b *builder) Scheme() string {
+	return b.scheme
+}
+
+type nopResolver struct {
+}
+
+func (*nopResolver) ResolveNow(resolver.ResolveNowOptions) {}
+
+func (*nopResolver) Close() {}
+
+func init() {
+	resolver.Register(&builder{scheme: unixScheme})
+	resolver.Register(&builder{scheme: unixAbstractScheme})
+}