v1.5.0

Added structutils

logging/TODO

@@ -3,9 +3,14 @@
   https://golang.org/pkg/runtime/#Caller
   -- log.LlongFile and log.Lshortfile flags don't currently work properly for StdLogger/FileLogger; they refer to the file in logging package rather than the caller.
 
+- StdLogger2; where stdout and stderr are both logged to depending on severity level.
+  - make configurable via OR bitmask
+
 - Suport remote loggers? (eventlog, syslog, systemd)
 
 - JSON logger? YAML logger? XML logger?
 
 - DOCS.
 -- Done, but flesh out.
+
+- Implement io.Writer interfaces

logging/doc.go

@@ -3,18 +3,19 @@ Package logging implements and presents various loggers under a unified interfac
 
 These particular loggers (logging.Logger) available are:
 
+	NullLogger
 	StdLogger
 	FileLogger
 	SystemDLogger (Linux only)
 	SyslogLogger (Linux only)
 	WinLogger (Windows only)
 
-There is a sixth type of logging.Logger, MultiLogger, that allows for multiple loggers to be written to with a single call.
+There is a seventh type of logging.Logger, MultiLogger, that allows for multiple loggers to be written to with a single call.
+As you may have guessed, NullLogger doesn't actually log anything but is fully "functional" as a logging.Logger.
 
 Note that for some Loggers, the prefix may be modified - "literal" loggers (StdLogger and FileLogger) will append a space to the end of the prefix.
 If this is undesired (unlikely), you will need to modify (Logger).Prefix and run (Logger).Logger.SetPrefix(yourPrefixHere) for the respective logger.
 
-
 Every logging.Logger type has the following methods that correspond to certain "levels".
 
 	Alert(s string, v ...interface{}) (err error)
@@ -36,6 +37,7 @@ Note that in the case of a MultiLogger, err (if not nil) will be a (r00t2.io/gou
 logging.Logger types also have the following methods:
 
 	DoDebug(d bool) (err error)
+	GetDebug() (d bool)
 	SetPrefix(p string) (err error)
 	GetPrefix() (p string, err error)
 	Setup() (err error)

logging/funcs_file.go

@@ -1,12 +1,12 @@
 package logging
 
 import (
-	`errors`
+	"errors"
 	"fmt"
-	`io/fs`
+	"io/fs"
 	"log"
 	"os"
-	`strings`
+	"strings"
 )
 
 // Setup sets up/configures a FileLogger and prepares it for use.
@@ -65,6 +65,14 @@ func (l *FileLogger) DoDebug(d bool) (err error) {
 	return
 }
 
+// GetDebug returns the debug status of this FileLogger.
+func (l *FileLogger) GetDebug() (d bool) {
+
+	d = l.EnableDebug
+
+	return
+}
+
 /*
 SetPrefix sets the prefix for this FileLogger.
 err will always be nil; it's there for interface-compat.

logging/funcs_multilogger.go

@@ -1,11 +1,11 @@
 package logging
 
 import (
-	`errors`
+	"errors"
-	`fmt`
+	"fmt"
-	`sync`
+	"sync"
 
-	`r00t2.io/goutils/multierr`
+	"r00t2.io/goutils/multierr"
 )
 
 // Setup sets up/configures a MultiLogger (and all its MultiLogger.Loggers) and prepares it for use.
@@ -114,6 +114,14 @@ func (m *MultiLogger) DoDebug(d bool) (err error) {
 	return
 }
 
+// GetDebug returns the debug status of this MultiLogger.
+func (m *MultiLogger) GetDebug() (d bool) {
+
+	d = m.EnableDebug
+
+	return
+}
+
 /*
 SetPrefix sets the prefix for this MultiLogger (and all its MultiLogger.Loggers).
 

logging/funcs_multilogger_mgr.go

@@ -1,10 +1,10 @@
 package logging
 
 import (
-	`path`
+	"path"
 
-	`github.com/google/uuid`
+	"github.com/google/uuid"
-	`r00t2.io/sysutils/paths`
+	"r00t2.io/sysutils/paths"
 )
 
 /*
@@ -145,6 +145,40 @@ func (m *MultiLogger) AddFileLogger(identifier string, logFlags int, logfilePath
 	return
 }
 
+/*
+	AddNullLogger adds a NullLogger to a MultiLogger.
+
+	identifier is a string to use to identify the added NullLogger in MultiLogger.Loggers.
+	If empty, one will be automatically generated.
+*/
+func (m *MultiLogger) AddNullLogger(identifier string) (err error) {
+
+	var exists bool
+	var prefix string
+
+	if identifier == "" {
+		identifier = uuid.New().String()
+	}
+
+	if _, exists = m.Loggers[identifier]; exists {
+		err = ErrExistingLogger
+		return
+	}
+
+	m.Loggers[identifier] = &NullLogger{}
+	if err = m.Loggers[identifier].Setup(); err != nil {
+		return
+	}
+
+	if prefix, err = m.Loggers[identifier].GetPrefix(); err != nil {
+		return
+	}
+
+	m.Loggers[identifier].Debug("logger initialized of type %T with prefix %v", m.Loggers[identifier], prefix)
+
+	return
+}
+
 // RemoveLogger will let you remove a Logger from MultiLogger.Loggers.
 func (m *MultiLogger) RemoveLogger(identifier string) (err error) {
 

logging/funcs_nulllogger.go

@@ -0,0 +1,74 @@
+package logging
+
+// Setup does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) Setup() (err error) {
+	return
+}
+
+// DoDebug does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) DoDebug(d bool) (err error) {
+	return
+}
+
+// GetDebug returns the debug status of this NullLogger. It will always return true. 🙃
+func (n *NullLogger) GetDebug() (d bool) {
+
+	d = true
+
+	return
+}
+
+// SetPrefix does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) SetPrefix(p string) (err error) {
+	return
+}
+
+// GetPrefix does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) GetPrefix() (p string, err error) {
+	return
+}
+
+// Shutdown does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) Shutdown() (err error) {
+	return
+}
+
+// Alert does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) Alert(s string, v ...interface{}) (err error) {
+	return
+}
+
+// Crit does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) Crit(s string, v ...interface{}) (err error) {
+	return
+}
+
+// Debug does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) Debug(s string, v ...interface{}) (err error) {
+	return
+}
+
+// Emerg does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) Emerg(s string, v ...interface{}) (err error) {
+	return
+}
+
+// Err does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) Err(s string, v ...interface{}) (err error) {
+	return
+}
+
+// Info does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) Info(s string, v ...interface{}) (err error) {
+	return
+}
+
+// Notice does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) Notice(s string, v ...interface{}) (err error) {
+	return
+}
+
+// Warning does nothing at all; it's here for interface compat. 🙃
+func (l *NullLogger) Warning(s string, v ...interface{}) (err error) {
+	return
+}

logging/funcs_std.go

@@ -2,10 +2,10 @@ package logging
 
 import (
 	"fmt"
-	`io`
+	"io"
-	`log`
+	"log"
-	`os`
+	"os"
-	`strings`
+	"strings"
 )
 
 /*
@@ -80,6 +80,14 @@ func (l *StdLogger) DoDebug(d bool) (err error) {
 	return
 }
 
+// GetDebug returns the debug status of this StdLogger.
+func (l *StdLogger) GetDebug() (d bool) {
+
+	d = l.EnableDebug
+
+	return
+}
+
 /*
 SetPrefix sets the prefix for this StdLogger.
 err will always be nil; it's there for interface-compat.

logging/funcs_sysd_linux.go

@@ -52,6 +52,14 @@ func (l *SystemDLogger) DoDebug(d bool) (err error) {
 	return
 }
 
+// GetDebug returns the debug status of this SystemDLogger.
+func (l *SystemDLogger) GetDebug() (d bool) {
+
+	d = l.EnableDebug
+
+	return
+}
+
 /*
 SetPrefix sets the prefix for this SystemDLogger.
 err will always be nil; it's there for interface-compat.

logging/funcs_syslog_linux.go

@@ -5,7 +5,7 @@ import (
 	"log"
 	"log/syslog"
 
-	`r00t2.io/goutils/multierr`
+	"r00t2.io/goutils/multierr"
 )
 
 // Setup sets up/configures a SyslogLogger and prepares it for use.
@@ -95,6 +95,14 @@ func (l *SyslogLogger) DoDebug(d bool) (err error) {
 	return
 }
 
+// GetDebug returns the debug status of this SyslogLogger.
+func (l *SyslogLogger) GetDebug() (d bool) {
+
+	d = l.EnableDebug
+
+	return
+}
+
 // SetPrefix sets the prefix for this SyslogLogger.
 func (l *SyslogLogger) SetPrefix(prefix string) (err error) {
 

logging/funcs_winlogger_windows.go

@@ -1,15 +1,15 @@
 package logging
 
 import (
-	`errors`
+	"errors"
-	`fmt`
+	"fmt"
-	`os`
+	"os"
-	`os/exec`
+	"os/exec"
-	`syscall`
+	"syscall"
 
-	`golang.org/x/sys/windows/registry`
+	"golang.org/x/sys/windows/registry"
-	`golang.org/x/sys/windows/svc/eventlog`
+	"golang.org/x/sys/windows/svc/eventlog"
-	`r00t2.io/sysutils/paths`
+	"r00t2.io/sysutils/paths"
 )
 
 /*
@@ -150,6 +150,14 @@ func (l *WinLogger) DoDebug(d bool) (err error) {
 	return
 }
 
+// GetDebug returns the debug status of this WinLogger.
+func (l *WinLogger) GetDebug() (d bool) {
+
+	d = l.EnableDebug
+
+	return
+}
+
 // SetPrefix sets the prefix for this WinLogger.
 func (l *WinLogger) SetPrefix(prefix string) (err error) {
 

logging/types.go

@@ -2,7 +2,7 @@ package logging
 
 import (
 	"log"
-	`os`
+	"os"
 )
 
 /*
@@ -18,6 +18,7 @@ type Logger interface {
 	Notice(s string, v ...interface{}) (err error)
 	Warning(s string, v ...interface{}) (err error)
 	DoDebug(d bool) (err error)
+	GetDebug() (d bool)
 	SetPrefix(p string) (err error)
 	GetPrefix() (p string, err error)
 	Setup() (err error)
@@ -86,6 +87,9 @@ type FileLogger struct {
 	writer *os.File
 }
 
+// NullLogger is used mainly for test implementations, mockup code, etc. It does absolutely nothing with all messages sent to it.
+type NullLogger struct{}
+
 // MultiLogger is used to contain one or more Loggers and present them all as a single Logger.
 type MultiLogger struct {
 	/*

structutils/consts.go

@@ -0,0 +1,5 @@
+package structutils
+
+const (
+	TagMapTrim tagMapOpt = iota
+)

structutils/funcs.go

@@ -0,0 +1,362 @@
+/*
+   GoUtils - a library to assist with various Golang-related functions
+   Copyright (C) 2020  Brent Saner
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+package structutils
+
+import (
+	`reflect`
+	`strings`
+)
+
+/*
+	TagToBoolMap takes struct field `field` and tag name `tagName`,
+	 optionally with options `opts`, and returns a map of the tag values.
+	The tag value string is assumed to be in the form of:
+		option[,option,option...]
+	and returns a map[string]bool (map[option]true).
+
+	If field does not have tag tagName, m will be nil.
+
+	See the TagMap* constants for opts.
+*/
+func TagToBoolMap(field reflect.StructField, tagName string, opts ...tagMapOpt) (m map[string]bool) {
+
+	var s string
+	var optSplit []string
+	var tagOpts map[tagMapOpt]bool = getTagMapOpts(opts)
+
+	s = field.Tag.Get(tagName)
+
+	if strings.TrimSpace(s) == "" {
+		return
+	}
+
+	optSplit = strings.Split(s, ",")
+	if optSplit == nil || len(optSplit) == 0 {
+		return
+	}
+	m = make(map[string]bool)
+	for _, o := range optSplit {
+		if tagOpts[TagMapTrim] {
+			o = strings.TrimSpace(o)
+		}
+		m[o] = true
+	}
+
+	return
+}
+
+/*
+	TagToBoolMapWithValue is like TagToBoolMap but additionally assumes the first value is an "identifier".
+	The tag value string is assumed to be in the form of:
+		value,option[,option,option...]
+	and returns a map[string]bool (map[option]true) with the value.
+*/
+func TagToBoolMapWithValue(field reflect.StructField, tagName string, opts ...tagMapOpt) (value string, m map[string]bool) {
+
+	var s string
+	var optSplit []string
+	var tagOpts map[tagMapOpt]bool = getTagMapOpts(opts)
+
+	s = field.Tag.Get(tagName)
+
+	if strings.TrimSpace(s) == "" {
+		return
+	}
+
+	optSplit = strings.Split(s, ",")
+	if optSplit == nil || len(optSplit) == 0 {
+		return
+	}
+	m = make(map[string]bool)
+	for idx, o := range optSplit {
+		if idx == 0 {
+			if tagOpts[TagMapTrim] {
+				o = strings.TrimSpace(o)
+			}
+			value = o
+			continue
+		}
+		if tagOpts[TagMapTrim] {
+			o = strings.TrimSpace(o)
+		}
+		m[o] = true
+	}
+
+	return
+}
+
+/*
+	TagToMixedMap combines TagToBoolMap and TagToStringMap.
+	It takes struct field `field` and tag name `tagName`,
+	and returns all single-value options in mapBool, and all key/value options in mapString.
+
+	If field does not have tag tagName, m will be nil.
+
+	See the TagMap* constants for opts.
+*/
+func TagToMixedMap(field reflect.StructField, tagName string, opts ...tagMapOpt) (mapBool map[string]bool, mapString map[string]string) {
+
+	var s string
+	var valStr string
+	var split []string
+	var kvSplit []string
+	var valSplit []string
+	var k string
+	var v string
+	var tagOpts map[tagMapOpt]bool = getTagMapOpts(opts)
+
+	s = field.Tag.Get(tagName)
+
+	if strings.TrimSpace(s) == "" {
+		return
+	}
+
+	split = strings.Split(s, ",")
+	if split == nil || len(split) == 0 {
+		return
+	}
+	mapBool = make(map[string]bool)
+	mapString = make(map[string]string)
+	for _, valStr = range split {
+		if strings.Contains(valStr, "=") {
+			kvSplit = strings.SplitN(valStr, "=", 2)
+			if kvSplit == nil || len(kvSplit) == 0 {
+				continue
+			}
+			k = valSplit[0]
+			switch len(valSplit) {
+			case 1:
+				v = ""
+			case 2:
+				v = kvSplit[1]
+			}
+			if tagOpts[TagMapTrim] {
+				k = strings.TrimSpace(k)
+				v = strings.TrimSpace(v)
+			}
+			mapString[k] = v
+		} else {
+			if tagOpts[TagMapTrim] {
+				valStr = strings.TrimSpace(valStr)
+			}
+			mapBool[valStr] = true
+		}
+	}
+
+	return
+}
+
+/*
+	TagToMixedMapWithValue combines TagToBoolMapWithValue and TagToStringMapWithValue.
+	It takes struct field `field` and tag name `tagName`,
+	and returns all single-value options in mapBool, and all key/value options in mapString
+	along with the first single-value option as value..
+
+	If field does not have tag tagName, m will be nil.
+
+	See the TagMap* constants for opts.
+*/
+func TagToMixedMapWithValue(field reflect.StructField, tagName string, opts ...tagMapOpt) (value string, mapBool map[string]bool, mapString map[string]string) {
+
+	var s string
+	var idx int
+	var valStr string
+	var split []string
+	var kvSplit []string
+	var valSplit []string
+	var k string
+	var v string
+	var tagOpts map[tagMapOpt]bool = getTagMapOpts(opts)
+
+	s = field.Tag.Get(tagName)
+
+	if strings.TrimSpace(s) == "" {
+		return
+	}
+
+	split = strings.Split(s, ",")
+	if split == nil || len(split) == 0 {
+		return
+	}
+	mapBool = make(map[string]bool)
+	mapString = make(map[string]string)
+	for idx, valStr = range split {
+		if idx == 0 {
+			if tagOpts[TagMapTrim] {
+				valStr = strings.TrimSpace(valStr)
+			}
+			value = valStr
+			continue
+		}
+		if strings.Contains(valStr, "=") {
+			kvSplit = strings.SplitN(valStr, "=", 2)
+			if kvSplit == nil || len(kvSplit) == 0 {
+				continue
+			}
+			k = valSplit[0]
+			switch len(valSplit) {
+			case 1:
+				v = ""
+			case 2:
+				v = kvSplit[1]
+			}
+			if tagOpts[TagMapTrim] {
+				k = strings.TrimSpace(k)
+				v = strings.TrimSpace(v)
+			}
+			mapString[k] = v
+		} else {
+			if tagOpts[TagMapTrim] {
+				valStr = strings.TrimSpace(valStr)
+			}
+			mapBool[valStr] = true
+		}
+	}
+
+	return
+}
+
+/*
+	TagToStringMap takes struct field `field` and tag name `tagName`,
+	 optionally with options `opts`, and returns a map of the tag values.
+	The tag value string is assumed to be in the form of:
+		key=value[,key=value,key=value...]
+	and returns a map[string]string (map[key]value).
+	It is proccessed in order; later duplicate keys overwrite previous ones.
+
+	If field does not have tag tagName, m will be nil.
+
+	If only a key is provided with no value, the value in the map will be an empty string.
+	(e.g. "foo,bar=baz" => map[string]string{"foo": "", "bar: "baz"}
+
+	See the TagMap* constants for opts.
+*/
+func TagToStringMap(field reflect.StructField, tagName string, opts ...tagMapOpt) (m map[string]string) {
+
+	var s string
+	var kvSplit []string
+	var valSplit []string
+	var k string
+	var v string
+	var tagOpts map[tagMapOpt]bool = getTagMapOpts(opts)
+
+	s = field.Tag.Get(tagName)
+
+	if strings.TrimSpace(s) == "" {
+		return
+	}
+
+	kvSplit = strings.Split(s, ",")
+	if kvSplit == nil || len(kvSplit) == 0 {
+		return
+	}
+	for _, kv := range kvSplit {
+		valSplit = strings.SplitN(kv, "=", 2)
+		if valSplit == nil || len(valSplit) == 0 {
+			continue
+		}
+		k = valSplit[0]
+		switch len(valSplit) {
+		case 1:
+			v = ""
+		case 2:
+			v = valSplit[1]
+			// It's not possible to have more than 2.
+		}
+		if m == nil {
+			m = make(map[string]string)
+		}
+		if tagOpts[TagMapTrim] {
+			k = strings.TrimSpace(k)
+			v = strings.TrimSpace(v)
+		}
+		m[k] = v
+	}
+
+	return
+}
+
+/*
+	TagToStringMapWithValue is like TagToStringMap but additionally assumes the first value is an "identifier".
+	The tag value string is assumed to be in the form of:
+		value,key=value[,key=value,key=value...]
+	and returns a map[string]string (map[key]value) with the value.
+*/
+func TagToStringMapWithValue(field reflect.StructField, tagName string, opts ...tagMapOpt) (value string, m map[string]string) {
+
+	var s string
+	var kvSplit []string
+	var valSplit []string
+	var k string
+	var v string
+	var tagOpts map[tagMapOpt]bool = getTagMapOpts(opts)
+
+	s = field.Tag.Get(tagName)
+
+	if strings.TrimSpace(s) == "" {
+		return
+	}
+
+	kvSplit = strings.Split(s, ",")
+	if kvSplit == nil || len(kvSplit) == 0 {
+		return
+	}
+	for idx, kv := range kvSplit {
+		if idx == 0 {
+			if tagOpts[TagMapTrim] {
+				kv = strings.TrimSpace(kv)
+			}
+			value = kv
+			continue
+		}
+		valSplit = strings.SplitN(kv, "=", 2)
+		if valSplit == nil || len(valSplit) == 0 {
+			continue
+		}
+		k = valSplit[0]
+		switch len(valSplit) {
+		case 1:
+			v = ""
+		case 2:
+			v = valSplit[1]
+			// It's not possible to have more than 2.
+		}
+		if m == nil {
+			m = make(map[string]string)
+		}
+		if tagOpts[TagMapTrim] {
+			k = strings.TrimSpace(k)
+			v = strings.TrimSpace(v)
+		}
+		m[k] = v
+	}
+
+	return
+}
+
+func getTagMapOpts(opts []tagMapOpt) (optMap map[tagMapOpt]bool) {
+
+	optMap = make(map[tagMapOpt]bool)
+
+	if opts == nil {
+		return
+	}
+
+	return
+}

structutils/types.go

@@ -0,0 +1,5 @@
+package structutils
+
+type (
+	tagMapOpt uint8
+)