added godoc comments and license notes for the gocloud.dev vendored code

tools/filesystem/blob/hex.go

@@ -1,5 +1,10 @@
 package blob
 
+import (
+	"fmt"
+	"strconv"
+)
+
 // Copied from gocloud.dev/blob to avoid nuances around the specific
 // HEX escaping/unescaping rules.
 //
@@ -19,11 +24,6 @@ package blob
 // limitations under the License.
 // -------------------------------------------------------------------
 
-import (
-	"fmt"
-	"strconv"
-)
-
 // HexEscape returns s, with all runes for which shouldEscape returns true
 // escaped to "__0xXXX__", where XXX is the hex representation of the rune
 // value. For example, " " would escape to "__0x20__".

tools/filesystem/blob/reader.go

@@ -8,6 +8,24 @@ import (
 	"time"
 )
 
+// Largely copied from gocloud.dev/blob.Reader to minimize breaking changes.
+//
+// -------------------------------------------------------------------
+// Copyright 2019 The Go Cloud Development Kit 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
+//
+//     https://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.
+// -------------------------------------------------------------------
+
 var _ io.ReadSeekCloser = (*Reader)(nil)
 
 // Reader reads bytes from a blob.

tools/filesystem/blob/writer.go

@@ -9,6 +9,24 @@ import (
 	"net/http"
 )
 
+// Largely copied from gocloud.dev/blob.Writer to minimize breaking changes.
+//
+// -------------------------------------------------------------------
+// Copyright 2019 The Go Cloud Development Kit 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
+//
+//     https://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.
+// -------------------------------------------------------------------
+
 var _ io.WriteCloser = (*Writer)(nil)
 
 // Writer writes bytes to a blob.