github.com/uber/kraken@v0.1.4/lib/store/cleanup.go (about)

     1  // Copyright (c) 2016-2019 Uber Technologies, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  package store
    15  
    16  import (
    17  	"fmt"
    18  	"os"
    19  	"sync"
    20  	"time"
    21  
    22  	"github.com/uber/kraken/lib/store/base"
    23  	"github.com/uber/kraken/lib/store/metadata"
    24  	"github.com/uber/kraken/utils/log"
    25  
    26  	"github.com/andres-erbsen/clock"
    27  	"github.com/uber-go/tally"
    28  )
    29  
    30  // CleanupConfig defines configuration for periodically cleaning up idle files.
    31  type CleanupConfig struct {
    32  	Disabled bool          `yaml:"disabled"`
    33  	Interval time.Duration `yaml:"interval"` // How often cleanup runs.
    34  	TTI      time.Duration `yaml:"tti"`      // Time to idle based on last access time.
    35  	TTL      time.Duration `yaml:"ttl"`      // Time to live regardless of access. If 0, disables TTL.
    36  }
    37  
    38  func (c CleanupConfig) applyDefaults() CleanupConfig {
    39  	if c.Interval == 0 {
    40  		c.Interval = 30 * time.Minute
    41  	}
    42  	if c.TTI == 0 {
    43  		c.TTI = 6 * time.Hour
    44  	}
    45  	return c
    46  }
    47  
    48  type cleanupManager struct {
    49  	clk      clock.Clock
    50  	stats    tally.Scope
    51  	stopOnce sync.Once
    52  	stopc    chan struct{}
    53  }
    54  
    55  func newCleanupManager(clk clock.Clock, stats tally.Scope) (*cleanupManager, error) {
    56  	hostname, err := os.Hostname()
    57  	if err != nil {
    58  		return nil, fmt.Errorf("look up hostname: %s", err)
    59  	}
    60  	stats = stats.Tagged(map[string]string{
    61  		"module":   "storecleanup",
    62  		"hostname": hostname,
    63  	})
    64  	return &cleanupManager{
    65  		clk:   clk,
    66  		stats: stats,
    67  		stopc: make(chan struct{}),
    68  	}, nil
    69  }
    70  
    71  // addJob starts a background cleanup task which removes idle files from op based
    72  // on the settings in config. op must set the desired states to clean before addJob
    73  // is called.
    74  func (m *cleanupManager) addJob(tag string, config CleanupConfig, op base.FileOp) {
    75  	config = config.applyDefaults()
    76  	if config.Disabled {
    77  		log.Warnf("Cleanup disabled for %s", op)
    78  		return
    79  	}
    80  	if config.TTL == 0 {
    81  		log.Warnf("TTL disabled for %s", op)
    82  	}
    83  
    84  	ticker := m.clk.Ticker(config.Interval)
    85  
    86  	usageGauge := m.stats.Tagged(map[string]string{"job": tag}).Gauge("disk_usage")
    87  
    88  	go func() {
    89  		for {
    90  			select {
    91  			case <-ticker.C:
    92  				log.Debugf("Performing cleanup of %s", op)
    93  				usage, err := m.scan(op, config.TTI, config.TTL)
    94  				if err != nil {
    95  					log.Errorf("Error scanning %s: %s", op, err)
    96  				}
    97  				usageGauge.Update(float64(usage))
    98  			case <-m.stopc:
    99  				ticker.Stop()
   100  				return
   101  			}
   102  		}
   103  	}()
   104  }
   105  
   106  func (m *cleanupManager) stop() {
   107  	m.stopOnce.Do(func() { close(m.stopc) })
   108  }
   109  
   110  // scan scans the op for idle or expired files. Also returns the total disk usage
   111  // of op.
   112  func (m *cleanupManager) scan(
   113  	op base.FileOp, tti time.Duration, ttl time.Duration) (usage int64, err error) {
   114  
   115  	names, err := op.ListNames()
   116  	if err != nil {
   117  		return 0, fmt.Errorf("list names: %s", err)
   118  	}
   119  	for _, name := range names {
   120  		info, err := op.GetFileStat(name)
   121  		if err != nil {
   122  			log.With("name", name).Errorf("Error getting file stat: %s", err)
   123  			continue
   124  		}
   125  		if ready, err := m.readyForDeletion(op, name, info, tti, ttl); err != nil {
   126  			log.With("name", name).Errorf("Error checking if file expired: %s", err)
   127  		} else if ready {
   128  			if err := op.DeleteFile(name); err != nil && err != base.ErrFilePersisted {
   129  				log.With("name", name).Errorf("Error deleting expired file: %s", err)
   130  			}
   131  		}
   132  		usage += info.Size()
   133  	}
   134  	return usage, nil
   135  }
   136  
   137  func (m *cleanupManager) readyForDeletion(
   138  	op base.FileOp,
   139  	name string,
   140  	info os.FileInfo,
   141  	tti time.Duration,
   142  	ttl time.Duration) (bool, error) {
   143  
   144  	if ttl > 0 && m.clk.Now().Sub(info.ModTime()) > ttl {
   145  		return true, nil
   146  	}
   147  
   148  	var lat metadata.LastAccessTime
   149  	if err := op.GetFileMetadata(name, &lat); os.IsNotExist(err) {
   150  		return false, nil
   151  	} else if err != nil {
   152  		return false, fmt.Errorf("get file lat: %s", err)
   153  	}
   154  	return m.clk.Now().Sub(lat.Time) > tti, nil
   155  }