VOL-1967 move api-server to separate repository

Current with voltha-go acf0adaf2d91ae72b55192cc8a939e0485918d16

Change-Id: I000ea6be0789e20c922bd671562b58a7120892ae
diff --git a/vendor/go.uber.org/zap/http_handler.go b/vendor/go.uber.org/zap/http_handler.go
new file mode 100644
index 0000000..1b0ecac
--- /dev/null
+++ b/vendor/go.uber.org/zap/http_handler.go
@@ -0,0 +1,81 @@
+// Copyright (c) 2016 Uber Technologies, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package zap
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"go.uber.org/zap/zapcore"
+)
+
+// ServeHTTP is a simple JSON endpoint that can report on or change the current
+// logging level.
+//
+// GET requests return a JSON description of the current logging level. PUT
+// requests change the logging level and expect a payload like:
+//   {"level":"info"}
+//
+// It's perfectly safe to change the logging level while a program is running.
+func (lvl AtomicLevel) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	type errorResponse struct {
+		Error string `json:"error"`
+	}
+	type payload struct {
+		Level *zapcore.Level `json:"level"`
+	}
+
+	enc := json.NewEncoder(w)
+
+	switch r.Method {
+
+	case http.MethodGet:
+		current := lvl.Level()
+		enc.Encode(payload{Level: &current})
+
+	case http.MethodPut:
+		var req payload
+
+		if errmess := func() string {
+			if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+				return fmt.Sprintf("Request body must be well-formed JSON: %v", err)
+			}
+			if req.Level == nil {
+				return "Must specify a logging level."
+			}
+			return ""
+		}(); errmess != "" {
+			w.WriteHeader(http.StatusBadRequest)
+			enc.Encode(errorResponse{Error: errmess})
+			return
+		}
+
+		lvl.SetLevel(*req.Level)
+		enc.Encode(req)
+
+	default:
+		w.WriteHeader(http.StatusMethodNotAllowed)
+		enc.Encode(errorResponse{
+			Error: "Only GET and PUT are supported.",
+		})
+	}
+}