Initial publication of ZFSSA CSI driver

pkg/utils/log_utils.go

@@ -0,0 +1,128 @@
+/*
+ * Copyright (c) 2021, Oracle and/or its affiliates.
+ * Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl/
+ */
+
+package utils
+
+import (
+	"flag"
+	"fmt"
+	"golang.org/x/net/context"
+	"io/ioutil"
+	"k8s.io/klog"
+	"log"
+	"os"
+	"strconv"
+	"sync/atomic"
+)
+
+const (
+	CSID int = iota	// CSI Driver
+	CTRL			// Controller Service
+	NODE			// Node Service
+	IDTY			// Identity Service
+	REST			// REST interface
+	UTIL			// Utilities that may be controller or node
+	SENTINEL
+)
+
+const MAX_LEVEL		int = 5
+
+type zLogger struct {
+	prefix	string
+	logger	[MAX_LEVEL]*log.Logger
+}
+
+// Type of the key being used to add the array of loggers to the context.
+type zLoggersKey	string
+
+var (
+	reqCounter			uint64
+	logLevelStr			string
+	logLevel			int
+	loggersPrefix		[SENTINEL]string
+	loggersTable		[MAX_LEVEL]*log.Logger
+	loggersKey			zLoggersKey = "zloggers"
+	loggerNOP			*log.Logger
+)
+
+// Log service initialization. The original loggers are created with a prefix identifying the
+// service (service, controller, node, indentifier, REST interface and utility), the node,
+// the driver and its version. These loggers will be clone for each request.
+func InitLogs(level, driverName, version, nodeID string) {
+
+	klog.InitFlags(nil)
+
+	logLevelStr = level
+	logLevel, _ = strconv.Atoi(level)
+	reqCounter = 0
+
+	_ = flag.Set("logtostderr", "true")
+	_ = flag.Set("v", logLevelStr)
+
+	loggersPrefix[CSID] = nodeID + "/" + driverName + "/" + version + "\n\t"
+	loggersPrefix[CTRL] = nodeID + "/" + driverName + "/" + version + "\n\t"
+	loggersPrefix[NODE] = nodeID + "/" + driverName + "/" + version + "\n\t"
+	loggersPrefix[IDTY] = nodeID + "/" + driverName + "/" + version + "\n\t"
+	loggersPrefix[REST] = nodeID + "/" + driverName + "/" + version + "\n\t"
+	loggersPrefix[UTIL] = nodeID + "/" + driverName + "/" + version + "\n\t"
+
+	for i := 0; i < MAX_LEVEL; i++ {
+		loggersTable[i] = log.New(os.Stdout, loggersPrefix[CSID] + "***  ",
+			log.Lmsgprefix|log.Ldate|log.Ltime|log.Lshortfile)
+	}
+
+	loggerNOP = log.New(ioutil.Discard, "NOP logger", log.LstdFlags)
+}
+
+// Creates a new context by duplicating the context passed in and adding a array of loggers
+// with a value added. The value is unique and is generated in this function. That value will
+// be systematically displayed each time any of the loggers in the array are called.
+func GetNewContext(ctx context.Context) context.Context {
+
+	loggers := new([SENTINEL]zLogger)
+	reqNum := fmt.Sprintf("%d", atomic.AddUint64(&reqCounter, 1))
+
+	for i := 0; i < SENTINEL; i++ {
+		loggers[i].prefix = loggersPrefix[i] + reqNum + "  "
+		for j := 0; j < MAX_LEVEL; j++ {
+			loggers[i].logger[j] = nil
+		}
+	}
+
+	return context.WithValue(ctx, loggersKey, loggers)
+}
+
+// Return the appropriate logger based on the service and level provided.
+func getLogger(ctx context.Context, sel int, level int) *log.Logger {
+
+	if level > logLevel {
+		return loggerNOP
+	}
+
+	level--
+
+	if ctx != nil {
+		loggers := ctx.Value(loggersKey).(*[SENTINEL]zLogger)
+		if loggers == nil {
+			panic("context without loggers")
+		}
+		if loggers[sel].logger[level] == nil {
+			// No logger has yet been created for this level
+			loggers[sel].logger[level] = log.New(os.Stdout, loggers[sel].prefix,
+				log.Lmsgprefix|log.Ldate|log.Ltime|log.Lshortfile)
+		}
+		return loggers[sel].logger[level]
+	}
+
+	return loggersTable[level]
+}
+
+// Public function returning the appropriate logger.
+func GetLogCSID(ctx context.Context, level int) *log.Logger {  return getLogger(ctx, CSID, level) }
+func GetLogCTRL(ctx context.Context, level int) *log.Logger {  return getLogger(ctx, CTRL, level) }
+func GetLogNODE(ctx context.Context, level int) *log.Logger {  return getLogger(ctx, NODE, level) }
+func GetLogIDTY(ctx context.Context, level int) *log.Logger {  return getLogger(ctx, IDTY, level) }
+func GetLogREST(ctx context.Context, level int) *log.Logger {  return getLogger(ctx, REST, level) }
+func GetLogUTIL(ctx context.Context, level int) *log.Logger {  return getLogger(ctx, UTIL, level) }