micro/debug/log/memory/memory.go
Asim Aslam 563768b58a
v3 refactor (#1868)
* Move to v3

Co-authored-by: Ben Toogood <bentoogood@gmail.com>
2020-07-27 13:22:00 +01:00

120 lines
2.6 KiB
Go

// Package memory provides an in memory log buffer
package memory
import (
"fmt"
"github.com/micro/go-micro/v3/debug/log"
"github.com/micro/go-micro/v3/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.Buffer.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.Buffer.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.Buffer.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.Buffer.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
}