1 files changed, 176 insertions, 0 deletions
diff --git a/go/vendor/google.golang.org/grpc/metadata/metadata.go b/go/vendor/google.golang.org/grpc/metadata/metadata.go
new file mode 100644
index 0000000..7ca4418
--- /dev/null
+++ b/go/vendor/google.golang.org/grpc/metadata/metadata.go
@@ -0,0 +1,176 @@
+/*
+ *
+ * Copyright 2014, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+// Package metadata define the structure of the metadata supported by gRPC library.
+// Please refer to http://www.grpc.io/docs/guides/wire.html for more information about custom-metadata.
+package metadata // import "google.golang.org/grpc/metadata"
+
+import (
+	"encoding/base64"
+	"fmt"
+	"strings"
+
+	"golang.org/x/net/context"
+)
+
+const (
+	binHdrSuffix = "-bin"
+)
+
+// encodeKeyValue encodes key and value qualified for transmission via gRPC.
+// Transmitting binary headers violates HTTP/2 spec.
+// TODO(zhaoq): Maybe check if k is ASCII also.
+func encodeKeyValue(k, v string) (string, string) {
+	k = strings.ToLower(k)
+	if strings.HasSuffix(k, binHdrSuffix) {
+		val := base64.StdEncoding.EncodeToString([]byte(v))
+		v = string(val)
+	}
+	return k, v
+}
+
+// DecodeKeyValue returns the original key and value corresponding to the
+// encoded data in k, v.
+// If k is a binary header and v contains comma, v is split on comma before decoded,
+// and the decoded v will be joined with comma before returned.
+func DecodeKeyValue(k, v string) (string, string, error) {
+	if !strings.HasSuffix(k, binHdrSuffix) {
+		return k, v, nil
+	}
+	vvs := strings.Split(v, ",")
+	for i, vv := range vvs {
+		val, err := base64.StdEncoding.DecodeString(vv)
+		if err != nil {
+			return "", "", err
+		}
+		vvs[i] = string(val)
+	}
+	return k, strings.Join(vvs, ","), nil
+}
+
+// MD is a mapping from metadata keys to values. Users should use the following
+// two convenience functions New and Pairs to generate MD.
+type MD map[string][]string
+
+// New creates a MD from given key-value map.
+// Keys are automatically converted to lowercase. And for keys having "-bin" as suffix, their values will be applied Base64 encoding.
+func New(m map[string]string) MD {
+	md := MD{}
+	for k, v := range m {
+		key, val := encodeKeyValue(k, v)
+		md[key] = append(md[key], val)
+	}
+	return md
+}
+
+// Pairs returns an MD formed by the mapping of key, value ...
+// Pairs panics if len(kv) is odd.
+// Keys are automatically converted to lowercase. And for keys having "-bin" as suffix, their values will be appplied Base64 encoding.
+func Pairs(kv ...string) MD {
+	if len(kv)%2 == 1 {
+		panic(fmt.Sprintf("metadata: Pairs got the odd number of input pairs for metadata: %d", len(kv)))
+	}
+	md := MD{}
+	var k string
+	for i, s := range kv {
+		if i%2 == 0 {
+			k = s
+			continue
+		}
+		key, val := encodeKeyValue(k, s)
+		md[key] = append(md[key], val)
+	}
+	return md
+}
+
+// Len returns the number of items in md.
+func (md MD) Len() int {
+	return len(md)
+}
+
+// Copy returns a copy of md.
+func (md MD) Copy() MD {
+	return Join(md)
+}
+
+// Join joins any number of MDs into a single MD.
+// The order of values for each key is determined by the order in which
+// the MDs containing those values are presented to Join.
+func Join(mds ...MD) MD {
+	out := MD{}
+	for _, md := range mds {
+		for k, v := range md {
+			out[k] = append(out[k], v...)
+		}
+	}
+	return out
+}
+
+type mdIncomingKey struct{}
+type mdOutgoingKey struct{}
+
+// NewContext is a wrapper for NewOutgoingContext(ctx, md).  Deprecated.
+func NewContext(ctx context.Context, md MD) context.Context {
+	return NewOutgoingContext(ctx, md)
+}
+
+// NewIncomingContext creates a new context with incoming md attached.
+func NewIncomingContext(ctx context.Context, md MD) context.Context {
+	return context.WithValue(ctx, mdIncomingKey{}, md)
+}
+
+// NewOutgoingContext creates a new context with outgoing md attached.
+func NewOutgoingContext(ctx context.Context, md MD) context.Context {
+	return context.WithValue(ctx, mdOutgoingKey{}, md)
+}
+
+// FromContext is a wrapper for FromIncomingContext(ctx).  Deprecated.
+func FromContext(ctx context.Context) (md MD, ok bool) {
+	return FromIncomingContext(ctx)
+}
+
+// FromIncomingContext returns the incoming MD in ctx if it exists.  The
+// returned md should be immutable, writing to it may cause races.
+// Modification should be made to the copies of the returned md.
+func FromIncomingContext(ctx context.Context) (md MD, ok bool) {
+	md, ok = ctx.Value(mdIncomingKey{}).(MD)
+	return
+}
+
+// FromOutgoingContext returns the outgoing MD in ctx if it exists.  The
+// returned md should be immutable, writing to it may cause races.
+// Modification should be made to the copies of the returned md.
+func FromOutgoingContext(ctx context.Context) (md MD, ok bool) {
+	md, ok = ctx.Value(mdOutgoingKey{}).(MD)
+	return
+}