chore: import upstream snapshot with attribution

debug/log/log.go

@@ -0,0 +1,58 @@
+// Package log provides debug logging
+package log
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+)
+
+var (
+	// Default buffer size if any.
+	DefaultSize = 1024
+	// DefaultLog logger.
+	DefaultLog = NewLog()
+	// Default formatter.
+	DefaultFormat = TextFormat
+)
+
+// Log is debug log interface for reading and writing logs.
+type Log interface {
+	// Read reads log entries from the logger
+	Read(...ReadOption) ([]Record, error)
+	// Write writes records to log
+	Write(Record) error
+	// Stream log records
+	Stream() (Stream, error)
+}
+
+// Record is log record entry.
+type Record struct {
+	// Timestamp of logged event
+	Timestamp time.Time `json:"timestamp"`
+	// Metadata to enrich log record
+	Metadata map[string]string `json:"metadata"`
+	// Value contains log entry
+	Message interface{} `json:"message"`
+}
+
+// Stream returns a log stream.
+type Stream interface {
+	Chan() <-chan Record
+	Stop() error
+}
+
+// Format is a function which formats the output.
+type FormatFunc func(Record) string
+
+// TextFormat returns text format.
+func TextFormat(r Record) string {
+	t := r.Timestamp.Format("2006-01-02 15:04:05")
+	return fmt.Sprintf("%s %v", t, r.Message)
+}
+
+// JSONFormat is a json Format func.
+func JSONFormat(r Record) string {
+	b, _ := json.Marshal(r)
+	return string(b)
+}

debug/log/memory/memory.go

@@ -0,0 +1,119 @@
+// Package memory provides an in memory log buffer
+package memory
+
+import (
+	"fmt"
+
+	"go-micro.dev/v6/debug/log"
+	"go-micro.dev/v6/internal/util/ring"
+)
+
+var (
+	// DefaultSize of the logger buffer.
+	DefaultSize = 1024
+)
+
+// memoryLog is default micro log.
+type memoryLog struct {
+	*ring.Buffer
+}
+
+// NewLog returns default Logger with.
+func NewLog(opts ...log.Option) log.Log {
+	// get default options
+	options := log.DefaultOptions()
+
+	// apply requested options
+	for _, o := range opts {
+		o(&options)
+	}
+
+	return &memoryLog{
+		Buffer: ring.New(options.Size),
+	}
+}
+
+// Write writes logs into logger.
+func (l *memoryLog) Write(r log.Record) error {
+	l.Put(fmt.Sprint(r.Message))
+	return nil
+}
+
+// Read reads logs and returns them.
+func (l *memoryLog) Read(opts ...log.ReadOption) ([]log.Record, error) {
+	options := log.ReadOptions{}
+	// initialize the read options
+	for _, o := range opts {
+		o(&options)
+	}
+
+	var entries []*ring.Entry
+	// if Since options ha sbeen specified we honor it
+	if !options.Since.IsZero() {
+		entries = l.Since(options.Since)
+	}
+
+	// only if we specified valid count constraint
+	// do we end up doing some serious if-else kung-fu
+	// if since constraint has been provided
+	// we return *count* number of logs since the given timestamp;
+	// otherwise we return last count number of logs
+	if options.Count > 0 {
+		switch len(entries) > 0 {
+		case true:
+			// if we request fewer logs than what since constraint gives us
+			if options.Count < len(entries) {
+				entries = entries[0:options.Count]
+			}
+		default:
+			entries = l.Get(options.Count)
+		}
+	}
+
+	records := make([]log.Record, 0, len(entries))
+	for _, entry := range entries {
+		record := log.Record{
+			Timestamp: entry.Timestamp,
+			Message:   entry.Value,
+		}
+		records = append(records, record)
+	}
+
+	return records, nil
+}
+
+// Stream returns channel for reading log records
+// along with a stop channel, close it when done.
+func (l *memoryLog) Stream() (log.Stream, error) {
+	// get stream channel from ring buffer
+	stream, stop := l.Buffer.Stream()
+	// make a buffered channel
+	records := make(chan log.Record, 128)
+	// get last 10 records
+	last10 := l.Get(10)
+
+	// stream the log records
+	go func() {
+		// first send last 10 records
+		for _, entry := range last10 {
+			records <- log.Record{
+				Timestamp: entry.Timestamp,
+				Message:   entry.Value,
+				Metadata:  make(map[string]string),
+			}
+		}
+		// now stream continuously
+		for entry := range stream {
+			records <- log.Record{
+				Timestamp: entry.Timestamp,
+				Message:   entry.Value,
+				Metadata:  make(map[string]string),
+			}
+		}
+	}()
+
+	return &logStream{
+		stream: records,
+		stop:   stop,
+	}, nil
+}

debug/log/memory/memory_test.go

@@ -0,0 +1,32 @@
+package memory
+
+import (
+	"reflect"
+	"testing"
+
+	"go-micro.dev/v6/debug/log"
+)
+
+func TestLogger(t *testing.T) {
+	// set size to some value
+	size := 100
+	// override the global logger
+	lg := NewLog(log.Size(size))
+	// make sure we have the right size of the logger ring buffer
+	if lg.(*memoryLog).Size() != size {
+		t.Errorf("expected buffer size: %d, got: %d", size, lg.(*memoryLog).Size())
+	}
+
+	// Log some cruft
+	lg.Write(log.Record{Message: "foobar"})
+	lg.Write(log.Record{Message: "foo bar"})
+
+	// Check if the logs are stored in the logger ring buffer
+	expected := []string{"foobar", "foo bar"}
+	entries, _ := lg.Read(log.Count(len(expected)))
+	for i, entry := range entries {
+		if !reflect.DeepEqual(entry.Message, expected[i]) {
+			t.Errorf("expected %s, got %s", expected[i], entry.Message)
+		}
+	}
+}

debug/log/memory/stream.go

@@ -0,0 +1,24 @@
+package memory
+
+import (
+	"go-micro.dev/v6/debug/log"
+)
+
+type logStream struct {
+	stream <-chan log.Record
+	stop   chan bool
+}
+
+func (l *logStream) Chan() <-chan log.Record {
+	return l.stream
+}
+
+func (l *logStream) Stop() error {
+	select {
+	case <-l.stop:
+		return nil
+	default:
+		close(l.stop)
+	}
+	return nil
+}

debug/log/noop/noop.go

@@ -0,0 +1,23 @@
+package noop
+
+import (
+	"go-micro.dev/v6/debug/log"
+)
+
+type noop struct{}
+
+func (n *noop) Read(...log.ReadOption) ([]log.Record, error) {
+	return nil, nil
+}
+
+func (n *noop) Write(log.Record) error {
+	return nil
+}
+
+func (n *noop) Stream() (log.Stream, error) {
+	return nil, nil
+}
+
+func NewLog(opts ...log.Option) log.Log {
+	return new(noop)
+}

debug/log/options.go

@@ -0,0 +1,70 @@
+package log
+
+import "time"
+
+// Option used by the logger.
+type Option func(*Options)
+
+// Options are logger options.
+type Options struct {
+	// Format specifies the output format
+	Format FormatFunc
+	// Name of the log
+	Name string
+	// Size is the size of ring buffer
+	Size int
+}
+
+// Name of the log.
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
+	}
+}
+
+// Size sets the size of the ring buffer.
+func Size(s int) Option {
+	return func(o *Options) {
+		o.Size = s
+	}
+}
+
+func Format(f FormatFunc) Option {
+	return func(o *Options) {
+		o.Format = f
+	}
+}
+
+// DefaultOptions returns default options.
+func DefaultOptions() Options {
+	return Options{
+		Size: DefaultSize,
+	}
+}
+
+// ReadOptions for querying the logs.
+type ReadOptions struct {
+	// Since what time in past to return the logs
+	Since time.Time
+	// Count specifies number of logs to return
+	Count int
+	// Stream requests continuous log stream
+	Stream bool
+}
+
+// ReadOption used for reading the logs.
+type ReadOption func(*ReadOptions)
+
+// Since sets the time since which to return the log records.
+func Since(s time.Time) ReadOption {
+	return func(o *ReadOptions) {
+		o.Since = s
+	}
+}
+
+// Count sets the number of log records to return.
+func Count(c int) ReadOption {
+	return func(o *ReadOptions) {
+		o.Count = c
+	}
+}

debug/log/os.go

@@ -0,0 +1,80 @@
+package log
+
+import (
+	"sync"
+
+	"github.com/google/uuid"
+	"go-micro.dev/v6/internal/util/ring"
+)
+
+// Should stream from OS.
+type osLog struct {
+	format FormatFunc
+	buffer *ring.Buffer
+	subs   map[string]*osStream
+
+	sync.RWMutex
+}
+
+type osStream struct {
+	stream chan Record
+}
+
+// Read reads log entries from the logger.
+func (o *osLog) Read(...ReadOption) ([]Record, error) {
+	var records []Record
+
+	// read the last 100 records
+	for _, v := range o.buffer.Get(100) {
+		records = append(records, v.Value.(Record))
+	}
+
+	return records, nil
+}
+
+// Write writes records to log.
+func (o *osLog) Write(r Record) error {
+	o.buffer.Put(r)
+	return nil
+}
+
+// Stream log records.
+func (o *osLog) Stream() (Stream, error) {
+	o.Lock()
+	defer o.Unlock()
+
+	// create stream
+	st := &osStream{
+		stream: make(chan Record, 128),
+	}
+
+	// save stream
+	o.subs[uuid.New().String()] = st
+
+	return st, nil
+}
+
+func (o *osStream) Chan() <-chan Record {
+	return o.stream
+}
+
+func (o *osStream) Stop() error {
+	return nil
+}
+
+func NewLog(opts ...Option) Log {
+	options := Options{
+		Format: DefaultFormat,
+	}
+	for _, o := range opts {
+		o(&options)
+	}
+
+	l := &osLog{
+		format: options.Format,
+		buffer: ring.New(1024),
+		subs:   make(map[string]*osStream),
+	}
+
+	return l
+}