Adding log levels to kit/server.Log*Msg funcs (#220)

* adding log levels to kit/server.Log*Msg funcs. resolves #13

* adding warn and debug loggers, updating docs

* adding tests

server/kit/kitserver_test.go

@@ -13,6 +13,7 @@ import (
 
 	"github.com/go-kit/kit/endpoint"
 	httptransport "github.com/go-kit/kit/transport/http"
+	"github.com/pkg/errors"
 	ocontext "golang.org/x/net/context"
 	"google.golang.org/grpc"
 
@@ -52,6 +53,22 @@ func TestKitServerHTTPMiddleware(t *testing.T) {
 	}
 }
 
+func TestKitServerHTTPError(t *testing.T) {
+	svr := kit.NewServer(&server{})
+
+	r := httptest.NewRequest(http.MethodGet, "http://localhost:8080/svc/error", nil)
+	w := httptest.NewRecorder()
+
+	// hit the server, expect error
+	svr.ServeHTTP(w, r)
+
+	resp := w.Result()
+
+	if resp.StatusCode != http.StatusInternalServerError {
+		t.Errorf("expected status code of 500, got %d", resp.StatusCode)
+	}
+}
+
 func TestKitServer(t *testing.T) {
 	shutdownErrChan := make(chan error)
 	go func() {
@@ -134,7 +151,13 @@ type server struct{}
 func (s *server) Middleware(e endpoint.Endpoint) endpoint.Endpoint {
 	return endpoint.Endpoint(func(ctx context.Context, r interface{}) (interface{}, error) {
 		kit.LogMsg(ctx, "kit middleware!")
-		return e(ctx, r)
+		kit.LogDebug(ctx, "debug: kit middleware!")
+		res, err := e(ctx, r)
+		if err != nil {
+			kit.LogWarning(ctx, "error found in middleware")
+			kit.LogErrorMsg(ctx, err, "the actual error")
+		}
+		return res, err
 	})
 }
 
@@ -158,6 +181,11 @@ func (s *server) HTTPEndpoints() map[string]map[string]kit.HTTPEndpoint {
 				Decoder:  catNameDecoder,
 			},
 		},
+		"/svc/error": {
+			"GET": {
+				Endpoint: s.error,
+			},
+		},
 	}
 }
 
@@ -197,3 +225,7 @@ func (s *server) getCatByName(ctx context.Context, _ interface{}) (interface{},
 	kit.Logger(ctx).Log("message", "getting ziggy")
 	return testCat, nil
 }
+
+func (s *server) error(ctx context.Context, _ interface{}) (interface{}, error) {
+	return nil, errors.New("doh!")
+}

server/kit/log.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/NYTimes/gizmo/observe"
 	"github.com/go-kit/kit/log"
+	"github.com/go-kit/kit/log/level"
 	"github.com/go-kit/kit/transport/http"
 	"google.golang.org/grpc/metadata"
 )
@@ -98,12 +99,28 @@ func AddLogKeyVals(ctx context.Context, l log.Logger) log.Logger {
 
 // LogMsg will log the given message to the server logger
 // with the key "message" along with all the common request headers or gRPC metadata.
+// This message will have an "info" log level associated with it.
 func LogMsg(ctx context.Context, message string) error {
-	return Logger(ctx).Log("message", message)
+	return level.Info(Logger(ctx)).Log("message", message)
+}
+
+// LogDebug will log the given message to the server logger
+// with the key "message" along with all the common request headers or gRPC metadata.
+// This message will have a "debug" log level associated with it.
+func LogDebug(ctx context.Context, message string) error {
+	return level.Debug(Logger(ctx)).Log("message", message)
+}
+
+// LogWarning will log the given message to the server logger
+// with the key "message" along with all the common request headers or gRPC metadata.
+// This message will have a "warn" log level associated with it.
+func LogWarning(ctx context.Context, message string) error {
+	return level.Warn(Logger(ctx)).Log("message", message)
 }
 
 // LogErrorMsg will log the given error under the key "error", the given message under
 // the key "message" along with all the common request headers or gRPC metadata.
+// This message will have an "error" log level associated with it.
 func LogErrorMsg(ctx context.Context, err error, message string) error {
-	return Logger(ctx).Log("error", err, "message", message)
+	return level.Error(Logger(ctx)).Log("error", err, "message", message)
 }