1 files changed, 188 insertions, 0 deletions
diff --git a/internal/log.go b/internal/log.go
new file mode 100644
index 00000000..fd2b84ab
--- /dev/null
+++ b/internal/log.go
@@ -0,0 +1,188 @@
+// Copyright 2017 Vector Creations Ltd
+//
+// 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 internal
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"path"
+	"path/filepath"
+	"runtime"
+	"strings"
+
+	"github.com/matrix-org/util"
+
+	"github.com/matrix-org/dendrite/internal/config"
+	"github.com/matrix-org/dugong"
+	"github.com/sirupsen/logrus"
+)
+
+type utcFormatter struct {
+	logrus.Formatter
+}
+
+func (f utcFormatter) Format(entry *logrus.Entry) ([]byte, error) {
+	entry.Time = entry.Time.UTC()
+	return f.Formatter.Format(entry)
+}
+
+// Logrus hook which wraps another hook and filters log entries according to their level.
+// (Note that we cannot use solely logrus.SetLevel, because Dendrite supports multiple
+// levels of logging at the same time.)
+type logLevelHook struct {
+	level logrus.Level
+	logrus.Hook
+}
+
+// Levels returns all the levels supported by this hook.
+func (h *logLevelHook) Levels() []logrus.Level {
+	levels := make([]logrus.Level, 0)
+
+	for _, level := range logrus.AllLevels {
+		if level <= h.level {
+			levels = append(levels, level)
+		}
+	}
+
+	return levels
+}
+
+// callerPrettyfier is a function that given a runtime.Frame object, will
+// extract the calling function's name and file, and return them in a nicely
+// formatted way
+func callerPrettyfier(f *runtime.Frame) (string, string) {
+	// Retrieve just the function name
+	s := strings.Split(f.Function, ".")
+	funcname := s[len(s)-1]
+
+	// Append a newline + tab to it to move the actual log content to its own line
+	funcname += "\n\t"
+
+	// Surround the filepath in brackets and append line number so IDEs can quickly
+	// navigate
+	filename := fmt.Sprintf(" [%s:%d]", f.File, f.Line)
+
+	return funcname, filename
+}
+
+// SetupPprof starts a pprof listener. We use the DefaultServeMux here because it is
+// simplest, and it gives us the freedom to run pprof on a separate port.
+func SetupPprof() {
+	if hostPort := os.Getenv("PPROFLISTEN"); hostPort != "" {
+		logrus.Warn("Starting pprof on ", hostPort)
+		go func() {
+			logrus.WithError(http.ListenAndServe(hostPort, nil)).Error("Failed to setup pprof listener")
+		}()
+	}
+}
+
+// SetupStdLogging configures the logging format to standard output. Typically, it is called when the config is not yet loaded.
+func SetupStdLogging() {
+	logrus.SetReportCaller(true)
+	logrus.SetFormatter(&utcFormatter{
+		&logrus.TextFormatter{
+			TimestampFormat:  "2006-01-02T15:04:05.000000000Z07:00",
+			FullTimestamp:    true,
+			DisableColors:    false,
+			DisableTimestamp: false,
+			QuoteEmptyFields: true,
+			CallerPrettyfier: callerPrettyfier,
+		},
+	})
+}
+
+// SetupHookLogging configures the logging hooks defined in the configuration.
+// If something fails here it means that the logging was improperly configured,
+// so we just exit with the error
+func SetupHookLogging(hooks []config.LogrusHook, componentName string) {
+	logrus.SetReportCaller(true)
+	for _, hook := range hooks {
+		// Check we received a proper logging level
+		level, err := logrus.ParseLevel(hook.Level)
+		if err != nil {
+			logrus.Fatalf("Unrecognised logging level %s: %q", hook.Level, err)
+		}
+
+		// Perform a first filter on the logs according to the lowest level of all
+		// (Eg: If we have hook for info and above, prevent logrus from processing debug logs)
+		if logrus.GetLevel() < level {
+			logrus.SetLevel(level)
+		}
+
+		switch hook.Type {
+		case "file":
+			checkFileHookParams(hook.Params)
+			setupFileHook(hook, level, componentName)
+		default:
+			logrus.Fatalf("Unrecognised logging hook type: %s", hook.Type)
+		}
+	}
+}
+
+// File type hooks should be provided a path to a directory to store log files
+func checkFileHookParams(params map[string]interface{}) {
+	path, ok := params["path"]
+	if !ok {
+		logrus.Fatalf("Expecting a parameter \"path\" for logging hook of type \"file\"")
+	}
+
+	if _, ok := path.(string); !ok {
+		logrus.Fatalf("Parameter \"path\" for logging hook of type \"file\" should be a string")
+	}
+}
+
+// Add a new FSHook to the logger. Each component will log in its own file
+func setupFileHook(hook config.LogrusHook, level logrus.Level, componentName string) {
+	dirPath := (hook.Params["path"]).(string)
+	fullPath := filepath.Join(dirPath, componentName+".log")
+
+	if err := os.MkdirAll(path.Dir(fullPath), os.ModePerm); err != nil {
+		logrus.Fatalf("Couldn't create directory %s: %q", path.Dir(fullPath), err)
+	}
+
+	logrus.AddHook(&logLevelHook{
+		level,
+		dugong.NewFSHook(
+			fullPath,
+			&utcFormatter{
+				&logrus.TextFormatter{
+					TimestampFormat:  "2006-01-02T15:04:05.000000000Z07:00",
+					DisableColors:    true,
+					DisableTimestamp: false,
+					DisableSorting:   false,
+					QuoteEmptyFields: true,
+				},
+			},
+			&dugong.DailyRotationSchedule{GZip: true},
+		),
+	})
+}
+
+//CloseAndLogIfError Closes io.Closer and logs the error if any
+func CloseAndLogIfError(ctx context.Context, closer io.Closer, message string) {
+	if closer == nil {
+		return
+	}
+	err := closer.Close()
+	if ctx == nil {
+		ctx = context.TODO()
+	}
+	if err != nil {
+		util.GetLogger(ctx).WithError(err).Error(message)
+	}
+}