package zlog

import "zgo.at/zlog"

Package zlog is a logging library.

Index ¶

• Constants
• func Error(err error)
• func Errorf(f string, v ...interface{})
• func Print(v ...interface{})
• func Printf(f string, v ...interface{})
• func ProfileCPU(path string) func()
• func ProfileHeap(path string)
• func Recover(cb ...func(Log) Log)
• type ConfigT
• func (c ConfigT) RunOutputs(l Log)
• type F
• type Log
• func Field(k string, v interface{}) Log
• func Fields(f F) Log
• func FieldsLocation() Log
• func FieldsRequest(r *http.Request) Log
• func Module(m string) Log
• func SetDebug(m ...string) Log
• func (l Log) Context(ctx context.Context)
• func (l Log) Debug(v ...interface{})
• func (l Log) Debugf(f string, v ...interface{})
• func (l Log) Error(err error)
• func (l Log) Errorf(f string, v ...interface{})
• func (l Log) Field(k string, v interface{}) Log
• func (l Log) Fields(f F) Log
• func (l Log) FieldsLocation() Log
• func (l Log) FieldsRequest(r *http.Request) Log
• func (l Log) FieldsSince() Log
• func (l Log) Module(m string) Log
• func (l Log) Print(v ...interface{})
• func (l Log) Printf(f string, v ...interface{})
• func (l Log) ResetTrace()
• func (l Log) SetDebug(m ...string) Log
• func (l Log) Since(msg string) Log
• func (l Log) Trace(v ...interface{}) Log
• func (l Log) Tracef(f string, v ...interface{}) Log
• type OutputFunc

Constants ¶

const (
	LevelInfo  = 0
	LevelErr   = 1
	LevelDbg   = 2
	LevelTrace = 3
)

Log levels.

Functions ¶

func Error ¶

func Error(err error)

func Errorf ¶

func Errorf(f string, v ...interface{})

func Print ¶

func Print(v ...interface{})

func Printf ¶

func Printf(f string, v ...interface{})

func ProfileCPU ¶

func ProfileCPU(path string) func()

ProfileCPU writes a memory if the path is non-empty.

This should be called on start and the returned function on end (e.g. defer).

func ProfileHeap ¶

func ProfileHeap(path string)

ProfileHeap writes a memory if the path is non-empty. This is usually called just before the program exits.

func Recover ¶

func Recover(cb ...func(Log) Log)

Recover from a panic.

Any panics will be recover()'d and reported with Error():

go func() {
    defer zlog.Recover()
    // ... do work...
}()

The first callback will be called before the Error() call, and can be used to modify the Log instance, for example to add fields:

defer zlog.Recover(func(l Log) Log {
    return l.Fields(zlog.F{"id": id})
})

Any other callbacks will be called after the Error() call. Modifying the Log instance has no real use.

Types ¶

type ConfigT ¶

type ConfigT struct {
	// Outputs for a Log entry.
	//
	// The default is to print to stderr for errors, and stdout for everything
	// else. Generally you want to keep this as a backup and add other
	// additional outputs, for example:
	//
	//    zlog.Config.Outputs = append(zlog.Config.Outputs, func(l Log) {
	//        if l.Level != LevelErr { // Only process errors.
	//            return
	//        }
	//
	//        // .. send to external error notification service ..
	//    })
	//
	//    zlog.Config.Outputs = append(zlog.Config.Outputs, func(l Log) {
	//        if l.Level == LevelErr { // Only process non-errors.
	//            return
	//        }
	//
	//        // .. send to external logging service ..
	//    })
	Outputs []OutputFunc

	// Filter stack traces, only used if the error is a github.com/pkg/errors
	// with a stack trace.
	// Useful to filter out HTTP middleware and other useless stuff.
	StackFilter *errorutil.Patterns

	// Global debug modules; always print debug information for these.
	Debug []string

	// Format function used by the default stdout/stderr output. This takes a
	// Log entry and formats it for output.
	Format func(Log) string

	// Time/date format as accepted by time.Format(); used in the default
	// Format() function.
	//
	// The default is to just print the time, which works well in development.
	// For production you probably want to use time.RFC3339 or some such.
	//
	// This is used in the standard format() function, not not elsewhere.
	FmtTime string
}

ConfigT is the configuration struct.

var Config ConfigT

Config for this package.

func (ConfigT) RunOutputs ¶

func (c ConfigT) RunOutputs(l Log)

type F ¶

type F map[string]interface{}

F are log fields.

type Log ¶

type Log struct {
	Ctx          context.Context
	Msg          string   // Log message; set with Print(), Debug(), etc.
	Err          error    // Original error, set with Error().
	Level        int      // 0: print, 1: err, 2: debug, 3: trace
	Modules      []string // Modules added to the logger.
	Data         F        // Fields added to the logger.
	DebugModules []string // List of modules to debug.
	Traces       []string // Traces added to the logger.
	// contains filtered or unexported fields
}

Log module.

func Field ¶

func Field(k string, v interface{}) Log

func Fields ¶

func Fields(f F) Log

func FieldsLocation ¶

func FieldsLocation() Log

FieldsLocation records the caller location.

func FieldsRequest ¶

func FieldsRequest(r *http.Request) Log

FieldsRequest adds information from a HTTP request as fields.

func Module ¶

func Module(m string) Log

Module adds a module to this Log entry.

You can add multiple Modules.

func SetDebug ¶

func SetDebug(m ...string) Log

func (Log) Context ¶

func (l Log) Context(ctx context.Context)

Context adds a context to the Log entry.

This isn't used by zlog, and mostly so that outputs can use it if needed.

func (Log) Debug ¶

func (l Log) Debug(v ...interface{})

Debug records debugging information. This won't do anything if the current module isn't beind debugged.

func (Log) Debugf ¶

func (l Log) Debugf(f string, v ...interface{})

Debugf records debugging information. This won't do anything if the current module isn't beind debugged.

func (Log) Error ¶

func (l Log) Error(err error)

Error prints an error.

func (Log) Errorf ¶

func (l Log) Errorf(f string, v ...interface{})

Errorf prints an error.

func (Log) Field ¶

func (l Log) Field(k string, v interface{}) Log

Field sets one data field.

func (Log) Fields ¶

func (l Log) Fields(f F) Log

Fields append data to the Log object.

func (Log) FieldsLocation ¶

func (l Log) FieldsLocation() Log

FieldsLocation records the caller location.

func (Log) FieldsRequest ¶

func (l Log) FieldsRequest(r *http.Request) Log

FieldsRequest adds information from a HTTP request as fields.

func (Log) FieldsSince ¶

func (l Log) FieldsSince() Log

FieldsSince adds timing information recorded with Since as fields.

func (Log) Module ¶

func (l Log) Module(m string) Log

func (Log) Print ¶

func (l Log) Print(v ...interface{})

Print an informational error.

func (Log) Printf ¶

func (l Log) Printf(f string, v ...interface{})

Printf an informational error.

func (Log) ResetTrace ¶

func (l Log) ResetTrace()

ResetTrace removes all trace logs added with Trace() and Tracef().

func (Log) SetDebug ¶

func (l Log) SetDebug(m ...string) Log

func (Log) Since ¶

func (l Log) Since(msg string) Log

Since records the duration since the last Since() or Module() call with the given message.

The result will be printed to stderr if this module is in the debug list. It can also be added to a Log with FieldsSince().

func (Log) Trace ¶

func (l Log) Trace(v ...interface{}) Log

func (Log) Tracef ¶

func (l Log) Tracef(f string, v ...interface{}) Log

type OutputFunc ¶

type OutputFunc func(Log)

OutputFunc is an output function, used in Config.Outputs.

Source Files ¶

output_std.go zlog.go