Make resume work

lul

.gitignore

@@ -1,3 +1,6 @@
 /.idea/
 .DS_Store
-/od-database-crawler
+/od-database-crawler
+*.log
+/queue/
+/crawled/

.travis.yml

@@ -0,0 +1,5 @@
+language: go
+
+go:
+  - "1.11.x"
+  - master

README.md

@@ -1,7 +1,24 @@
 # od-database Go crawler 🚀
+[![Build Status](https://travis-ci.org/terorie/od-database-crawler.svg?branch=master)](https://travis-ci.org/terorie/od-database-crawler)
 > by terorie 2018 :P
 
  * Crawler for [__OD-Database__](https://github.com/simon987/od-database)
  * Crawls HTTP open directories (standard Web Server Listings)
  * Gets name, path, size and modification time of all files
  * Lightweight and fast: __over 9000 requests per second__ on a standard laptop
+
+https://od-db.the-eye.eu/
+
+#### Usage
+
+ 1. With Config File (if `config.yml` found in working dir)
+    - Download [default config](https://github.com/terorie/od-database-crawler/blob/master/config.yml)
+    - Set `server.url` and `server.token`
+    - Start with `./od-database-crawler server --config <file>`
+ 
+ 2. With Flags or env
+    - Override config file if it exists
+    - `--help` for list of flags
+    - Every flag is available as an environment variable:
+      `--server.crawl_stats` ➡️ `OD_SERVER_CRAWL_STATS`
+    - Start with `./od-database-crawler server <flags>`

config.go

@@ -4,6 +4,7 @@ import (
 	"bufio"
 	"fmt"
 	"github.com/sirupsen/logrus"
+	"github.com/spf13/pflag"
 	"github.com/spf13/viper"
 	"io"
 	"os"
@@ -20,25 +21,33 @@ var config struct {
 	Retries    int
 	Workers    int
 	UserAgent  string
-	Timeout    time.Duration
 	Tasks      int32
-	CrawlStats time.Duration
-	AllocStats time.Duration
 	Verbose    bool
 	PrintHTTP  bool
+	JobBufferSize int
 }
 
+var onlineMode bool
+
 const (
 	ConfServerUrl  = "server.url"
 	ConfToken      = "server.token"
 	ConfServerTimeout = "server.timeout"
 	ConfRecheck    = "server.recheck"
+	ConfCooldown   = "server.cooldown"
 	ConfChunkSize  = "server.upload_chunk"
+	ConfUploadRetries = "server.upload_retries"
+	ConfUploadRetryInterval = "server.upload_retry_interval"
+
 	ConfTasks      = "crawl.tasks"
 	ConfRetries    = "crawl.retries"
 	ConfWorkers    = "crawl.connections"
 	ConfUserAgent  = "crawl.user-agent"
+	ConfDialTimeout = "crawl.dial_timeout"
 	ConfTimeout    = "crawl.timeout"
+	ConfJobBufferSize = "crawl.job_buffer"
+	ConfResume     = "crawl.resume"
+
 	ConfCrawlStats = "output.crawl_stats"
 	ConfAllocStats = "output.resource_stats"
 	ConfVerbose    = "output.verbose"
@@ -47,38 +56,108 @@ const (
 )
 
 func prepareConfig() {
-	viper.SetDefault(ConfRetries, 5)
-	viper.SetDefault(ConfWorkers, 2)
-	viper.SetDefault(ConfTasks, 3)
-	viper.SetDefault(ConfUserAgent, "")
-	viper.SetDefault(ConfTimeout, 10 * time.Second)
-	viper.SetDefault(ConfCrawlStats, 3 * time.Second)
-	viper.SetDefault(ConfAllocStats, 0)
-	viper.SetDefault(ConfVerbose, false)
-	viper.SetDefault(ConfPrintHTTP, false)
-	viper.SetDefault(ConfLogFile, "")
-	viper.SetDefault(ConfRecheck, 3 * time.Second)
-	viper.SetDefault(ConfChunkSize, "1 MB")
+	pf := rootCmd.PersistentFlags()
+
+	pf.SortFlags = false
+	pf.StringVar(&configFile, "config", "", "Config file")
+	configFile = os.Getenv("OD_CONFIG")
+
+	pf.String(ConfServerUrl, "http://od-db.the-eye.eu/api", "OD-DB server URL")
+
+	pf.String(ConfToken, "", "OD-DB access token (env OD_SERVER_TOKEN)")
+
+	pf.Duration(ConfServerTimeout, 60 * time.Second, "OD-DB request timeout")
+
+	pf.Duration(ConfRecheck, 1 * time.Second, "OD-DB: Poll interval for new jobs")
+
+	pf.Duration(ConfCooldown, 30 * time.Second, "OD-DB: Time to wait after a server-side error")
+
+	pf.String(ConfChunkSize, "1 MB", "OD-DB: Result upload chunk size")
+
+	pf.Uint(ConfUploadRetries, 10, "OD-DB: Max upload retries")
+
+	pf.Duration(ConfUploadRetryInterval, 30 * time.Second, "OD-DB: Time to wait between upload retries")
+
+	pf.Uint(ConfTasks, 100, "Crawler: Max concurrent tasks")
+
+	pf.Uint(ConfWorkers, 4, "Crawler: Connections per server")
+
+	pf.Uint(ConfRetries, 5, "Crawler: Request retries")
+
+	pf.Duration(ConfDialTimeout, 10 * time.Second, "Crawler: Handshake timeout")
+
+	pf.Duration(ConfTimeout, 30 * time.Second, "Crawler: Request timeout")
+
+	pf.String(ConfUserAgent, "Mozilla/5.0 (X11; od-database-crawler) Gecko/20100101 Firefox/52.0", "Crawler: User-Agent")
+
+	pf.Uint(ConfJobBufferSize, 5000, "Crawler: Task queue cache size")
+
+	pf.Duration(ConfResume, 72 * time.Hour, "Crawler: Resume tasks not older than x")
+
+	pf.Duration(ConfCrawlStats, time.Second, "Log: Crawl stats interval")
+
+	pf.Duration(ConfAllocStats, 10 * time.Second, "Log: Resource stats interval")
+
+	pf.Bool(ConfVerbose, false, "Log: Print every listed dir")
+
+	pf.Bool(ConfPrintHTTP, false, "Log: Print HTTP client errors")
+
+	pf.String(ConfLogFile, "crawler.log", "Log file")
+
+	// Bind all flags to Viper
+	pf.VisitAll(func(flag *pflag.Flag) {
+		s := flag.Name
+		s = strings.TrimLeft(s, "-")
+
+		if err := viper.BindPFlag(s, flag); err != nil {
+			panic(err)
+		}
+		var envKey string
+		envKey = strings.Replace(s, ".", "_", -1)
+		envKey = strings.ToUpper(envKey)
+		envKey = "OD_" + envKey
+		if err := viper.BindEnv(s, envKey); err != nil {
+			panic(err)
+		}
+	})
 }
 
 func readConfig() {
-	viper.AddConfigPath(".")
-	viper.SetConfigName("config")
-	err := viper.ReadInConfig()
-	if err != nil {
-		fmt.Fprintln(os.Stderr, err)
-		os.Exit(1)
+	// If config.yml in working dir, use it
+	if configFile == "" {
+		_, err := os.Stat("config.yml")
+		if err == nil {
+			configFile = "config.yml"
+		}
 	}
 
-	config.ServerUrl = viper.GetString(ConfServerUrl)
-	if config.ServerUrl == "" {
-		configMissing(ConfServerUrl)
-	}
-	config.ServerUrl = strings.TrimRight(config.ServerUrl, "/")
+	if configFile != "" {
+		confF, err := os.Open(configFile)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(1)
+		}
+		defer confF.Close()
 
-	config.Token = viper.GetString(ConfToken)
-	if config.Token == "" {
-		configMissing(ConfToken)
+		viper.SetConfigType("yml")
+		err = viper.ReadConfig(confF)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(1)
+		}
+	}
+
+	if onlineMode {
+		config.ServerUrl = viper.GetString(ConfServerUrl)
+		if config.ServerUrl == "" {
+			configMissing(ConfServerUrl)
+		}
+		config.ServerUrl = strings.TrimRight(config.ServerUrl, "/")
+
+		config.Token = viper.GetString(ConfToken)
+		if config.Token == "" {
+			configMissing(ConfToken)
+		}
 	}
 
 	config.ServerTimeout = viper.GetDuration(ConfServerTimeout)
@@ -107,11 +186,11 @@ func readConfig() {
 
 	config.UserAgent = viper.GetString(ConfUserAgent)
 
-	config.Timeout = viper.GetDuration(ConfTimeout)
+	setDialTimeout(viper.GetDuration(ConfDialTimeout))
 
-	config.CrawlStats = viper.GetDuration(ConfCrawlStats)
+	setTimeout(viper.GetDuration(ConfTimeout))
 
-	config.AllocStats = viper.GetDuration(ConfAllocStats)
+	config.JobBufferSize = viper.GetInt(ConfJobBufferSize)
 
 	config.Verbose = viper.GetBool(ConfVerbose)
 	if config.Verbose {

config.yml

@@ -15,10 +15,17 @@ server:
   # between /task/get requests to the server.
   recheck: 1s
 
+  # Time to wait after receiving an error
+  # from the server. Doesn't apply to uploads.
+  cooldown: 30s
+
   # Upload chunk size
   # If the value is too high, the upload fails.
   upload_chunk: 1 MB
 
+  upload_retries: 10
+  upload_retry_interval: 30s
+
 # Log output settings
 output:
   # Crawl statistics
@@ -46,15 +53,32 @@ crawl:
   # Please be careful with this setting!
   # The crawler fires fast and more than
   # ten connections can overwhelm a server.
-  connections: 10
+  connections: 4
 
   # How often to retry getting data
   # from the site before giving up
   retries: 5
 
+  # Time before discarding a failed connection attempt
+  dial_timeout: 10s
+
   # Time before discarding a network request
-  timeout: 10s
+  timeout: 30s
 
   # Crawler User-Agent
   # If empty, no User-Agent header is sent.
   user-agent: "Mozilla/5.0 (X11; od-database-crawler) Gecko/20100101 Firefox/52.0"
+
+  # Job buffer size (per task)
+  # Higher values cause less disk writes
+  # but require more memory.
+  #
+  # The job queue contains all URLs
+  # that should be crawled next.
+  # As it grows very large over time,
+  # it's kept mainly on disk.
+  # This sets how many jobs are kept
+  # in memory.
+  # A negative value will cause all jobs
+  # to be stored in memory. (Don't do this)
+  job_buffer: 5000

crawl.go

@@ -8,6 +8,7 @@ import (
 	"github.com/valyala/fasthttp"
 	"golang.org/x/crypto/blake2b"
 	"golang.org/x/net/html"
+	"net"
 	"path"
 	"strconv"
 	"strings"
@@ -20,6 +21,17 @@ var client = fasthttp.Client {
 	},
 }
 
+func setDialTimeout(d time.Duration) {
+	client.Dial = func(addr string) (net.Conn, error) {
+		return fasthttp.DialTimeout(addr, d)
+	}
+}
+
+func setTimeout(d time.Duration) {
+	client.ReadTimeout = d
+	client.WriteTimeout = d / 2
+}
+
 func GetDir(j *Job, f *File) (links []fasturl.URL, err error) {
 	f.IsDir = true
 	f.Name = path.Base(j.Uri.Path)
@@ -33,7 +45,7 @@ func GetDir(j *Job, f *File) (links []fasturl.URL, err error) {
 	res := fasthttp.AcquireResponse()
 	defer fasthttp.ReleaseResponse(res)
 
-	err = client.DoTimeout(req, res, config.Timeout)
+	err = client.Do(req, res)
 	fasthttp.ReleaseRequest(req)
 
 	if err != nil {
@@ -46,10 +58,16 @@ func GetDir(j *Job, f *File) (links []fasturl.URL, err error) {
 	}
 
 	body := res.Body()
+	return ParseDir(body, &j.Uri)
+}
+
+func ParseDir(body []byte, baseUri *fasturl.URL) (links []fasturl.URL, err error) {
 	doc := html.NewTokenizer(bytes.NewReader(body))
 
 	var linkHref string
 	for {
+		err = nil
+
 		tokenType := doc.Next()
 		if tokenType == html.ErrorToken {
 			break
@@ -80,36 +98,34 @@ func GetDir(j *Job, f *File) (links []fasturl.URL, err error) {
 				linkHref = ""
 
 				if strings.LastIndexByte(href, '?') != -1 {
-					goto nextToken
+					continue
 				}
 
 				switch href {
 				case "", " ", ".", "..", "/":
-					goto nextToken
+					continue
 				}
 
 				if strings.Contains(href, "../") {
-					goto nextToken
+					continue
 				}
 
 				var link fasturl.URL
-				err = j.Uri.ParseRel(&link, href)
+				err = baseUri.ParseRel(&link, href)
 				if err != nil {
 					continue
 				}
 
-				if link.Scheme != j.Uri.Scheme ||
-					link.Host != j.Uri.Host ||
-					link.Path == j.Uri.Path ||
-					!strings.HasPrefix(link.Path, j.Uri.Path) {
+				if link.Scheme != baseUri.Scheme ||
+					link.Host != baseUri.Host ||
+					link.Path == baseUri.Path ||
+					!strings.HasPrefix(link.Path, baseUri.Path) {
 					continue
 				}
 
 				links = append(links, link)
 			}
 		}
-
-	nextToken:
 	}
 
 	return
@@ -132,7 +148,7 @@ func GetFile(u fasturl.URL, f *File) (err error) {
 	res.SkipBody = true
 	defer fasthttp.ReleaseResponse(res)
 
-	err = client.DoTimeout(req, res, config.Timeout)
+	err = client.Do(req, res)
 	fasthttp.ReleaseRequest(req)
 
 	if err != nil {

crawl_nginx_test.go

@@ -0,0 +1,117 @@
+package main
+
+import (
+	"github.com/terorie/od-database-crawler/fasturl"
+	"testing"
+)
+
+func TestParseDirNginx(t *testing.T) {
+	var u fasturl.URL
+	err := u.Parse("https://the-eye.eu/public/")
+	if err != nil {
+		t.Fatal("Failed to parse URL", err)
+	}
+
+	links, err := ParseDir([]byte(nginxListing), &u)
+	if err != nil {
+		t.Fatal("Failed to extract links", err)
+	}
+
+	if len(links) != len(nginxLinks) {
+		t.Fatalf("Expected %d links, got %d",
+			len(nginxLinks), len(links))
+	}
+
+	for i := 0; i < len(links); i++ {
+		gotLink := links[i].String()
+		expLink := nginxLinks[i]
+
+		if gotLink != expLink {
+			t.Errorf(`Expected "%s" got "%s"`,
+				expLink, gotLink)
+		}
+	}
+}
+
+var nginxLinks = []string {
+	"https://the-eye.eu/public/AppleArchive/",
+	"https://the-eye.eu/public/AudioBooks/",
+	"https://the-eye.eu/public/Books/",
+	"https://the-eye.eu/public/Comics/",
+	"https://the-eye.eu/public/Games/",
+	"https://the-eye.eu/public/Icons/",
+	"https://the-eye.eu/public/Images/",
+	"https://the-eye.eu/public/JFK_Files/",
+	"https://the-eye.eu/public/MSDN/",
+	"https://the-eye.eu/public/Music/",
+	"https://the-eye.eu/public/Operating%20Systems/",
+	"https://the-eye.eu/public/Posters/",
+	"https://the-eye.eu/public/Psychedelics/",
+	"https://the-eye.eu/public/Psychoactives/",
+	"https://the-eye.eu/public/Radio/",
+	"https://the-eye.eu/public/Random/",
+	"https://the-eye.eu/public/Site-Dumps/",
+	"https://the-eye.eu/public/Software/",
+	"https://the-eye.eu/public/Strategic%20Intelligence%20Network/",
+	"https://the-eye.eu/public/WorldTracker.org/",
+	"https://the-eye.eu/public/concen.org/",
+	"https://the-eye.eu/public/freenrg.info/",
+	"https://the-eye.eu/public/murdercube.com/",
+	"https://the-eye.eu/public/parazite/",
+	"https://the-eye.eu/public/ripreddit/",
+	"https://the-eye.eu/public/rom/",
+	"https://the-eye.eu/public/touhou/",
+	"https://the-eye.eu/public/vns/",
+	"https://the-eye.eu/public/xbins/",
+	"https://the-eye.eu/public/xbins.diodematrix/",
+	"https://the-eye.eu/public/Rclone_for_Scrubs.pdf",
+	"https://the-eye.eu/public/Wget_Linux_Guide.pdf",
+	"https://the-eye.eu/public/Wget_Windows_Guide.pdf",
+	"https://the-eye.eu/public/rclone_guide.pdf",
+	"https://the-eye.eu/public/wget-noobs-guide.pdf",
+	"https://the-eye.eu/public/xbox-scene_Aug2014.7z",
+}
+
+const nginxListing =
+`<html>
+<head><title>Index of /public/</title></head>
+<body bgcolor="white">
+<h1>Index of /public/</h1><hr><pre><a href="../">../</a>
+<a href="AppleArchive/">AppleArchive/</a>                                      03-Nov-2017 18:13       -
+<a href="AudioBooks/">AudioBooks/</a>                                        29-Sep-2018 19:47       -
+<a href="Books/">Books/</a>                                             27-Nov-2018 17:50       -
+<a href="Comics/">Comics/</a>                                            05-Nov-2018 21:37       -
+<a href="Games/">Games/</a>                                             28-Nov-2018 11:54       -
+<a href="Icons/">Icons/</a>                                             22-May-2018 07:47       -
+<a href="Images/">Images/</a>                                            21-Jan-2018 03:21       -
+<a href="JFK_Files/">JFK_Files/</a>                                         03-Nov-2017 17:03       -
+<a href="MSDN/">MSDN/</a>                                              03-Nov-2017 15:48       -
+<a href="Music/">Music/</a>                                             02-Mar-2018 15:47       -
+<a href="Operating%20Systems/">Operating Systems/</a>                                 25-Apr-2018 07:18       -
+<a href="Posters/">Posters/</a>                                           07-Jul-2018 01:12       -
+<a href="Psychedelics/">Psychedelics/</a>                                      11-Apr-2018 05:45       -
+<a href="Psychoactives/">Psychoactives/</a>                                     18-May-2018 02:58       -
+<a href="Radio/">Radio/</a>                                             09-Jun-2018 15:49       -
+<a href="Random/">Random/</a>                                            04-Dec-2018 12:33       -
+<a href="Site-Dumps/">Site-Dumps/</a>                                        15-Dec-2018 11:04       -
+<a href="Software/">Software/</a>                                          27-Nov-2017 00:22       -
+<a href="Strategic%20Intelligence%20Network/">Strategic Intelligence Network/</a>                    17-Nov-2017 16:35       -
+<a href="WorldTracker.org/">WorldTracker.org/</a>                                  12-Apr-2018 04:16       -
+<a href="concen.org/">concen.org/</a>                                        08-Oct-2018 14:08       -
+<a href="freenrg.info/">freenrg.info/</a>                                      19-Dec-2017 10:59       -
+<a href="murdercube.com/">murdercube.com/</a>                                    06-Dec-2017 10:45       -
+<a href="parazite/">parazite/</a>                                          20-Nov-2017 21:25       -
+<a href="ripreddit/">ripreddit/</a>                                         04-Aug-2018 14:30       -
+<a href="rom/">rom/</a>                                               28-Nov-2018 14:15       -
+<a href="touhou/">touhou/</a>                                            03-Nov-2017 11:07       -
+<a href="vns/">vns/</a>                                               03-Nov-2017 11:36       -
+<a href="xbins/">xbins/</a>                                             03-Nov-2017 17:23       -
+<a href="xbins.diodematrix/">xbins.diodematrix/</a>                                 21-Sep-2018 22:33       -
+<a href="Rclone_for_Scrubs.pdf">Rclone_for_Scrubs.pdf</a>                              04-Sep-2018 13:31    315K
+<a href="Wget_Linux_Guide.pdf">Wget_Linux_Guide.pdf</a>                               21-Dec-2017 20:28    168K
+<a href="Wget_Windows_Guide.pdf">Wget_Windows_Guide.pdf</a>                             25-Nov-2017 17:59    867K
+<a href="rclone_guide.pdf">rclone_guide.pdf</a>                                   03-Sep-2018 23:37    315K
+<a href="wget-noobs-guide.pdf">wget-noobs-guide.pdf</a>                               21-Dec-2017 20:29    168K
+<a href="xbox-scene_Aug2014.7z">xbox-scene_Aug2014.7z</a>                              26-Oct-2017 23:09      1G
+</pre><hr></body>
+</html>`

crawl_test.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+	"bytes"
+	"github.com/PuerkitoBio/goquery"
+	"github.com/terorie/od-database-crawler/fasturl"
+	"net/url"
+	"strings"
+	"testing"
+)
+
+func BenchmarkParseDir(b *testing.B) {
+	for n := 0; n < b.N; n++ {
+		var u fasturl.URL
+		err := u.Parse("http://archive.ubuntu.com/ubuntu/indices/")
+		if err != nil {
+			b.Fatal("Failed to parse URL", err)
+		}
+
+		_, err = ParseDir([]byte(apache2Listing), &u)
+		if err != nil {
+			b.Fatal("Failed to extract links", err)
+		}
+	}
+}
+
+func BenchmarkParseDirReference(b *testing.B) {
+	for n := 0; n < b.N; n++ {
+		u, err := url.Parse("http://archive.ubuntu.com/ubuntu/indices/")
+		if err != nil {
+			b.Fatal("Failed to parse URL", err)
+		}
+
+		_, err = referenceParseDir([]byte(apache2Listing), u)
+		if err != nil {
+			b.Fatal("Failed to extract links", err)
+		}
+	}
+}
+
+func referenceParseDir(body []byte, baseUri *url.URL) (links []*url.URL, err error) {
+	doc, err := goquery.NewDocumentFromReader(bytes.NewReader(body))
+	if err != nil { return nil, err }
+
+	doc.Find("a[href]").Each(func(i int, s *goquery.Selection) {
+		href, _ := s.Attr("href")
+
+		sub, err := baseUri.Parse(href)
+		if err != nil { return } // continue
+
+		if !strings.HasPrefix(sub.String(), baseUri.String()) {
+			return // continue
+		}
+
+		links = append(links, sub)
+	})
+
+	return
+}

ds/redblackhash/redblack.go

@@ -15,7 +15,10 @@ package redblackhash
 
 import (
 	"bytes"
+	"encoding/binary"
+	"encoding/hex"
 	"fmt"
+	"io"
 	"sync"
 )
 
@@ -43,6 +46,13 @@ type Node struct {
 	Parent *Node
 }
 
+type nodeHeader struct {
+	Key   *Key
+	Color color
+}
+
+var o = binary.BigEndian
+
 func (k *Key) Compare(o *Key) int {
 	return bytes.Compare(k[:], o[:])
 }
@@ -233,7 +243,7 @@ func (tree *Tree) String() string {
 }
 
 func (node *Node) String() string {
-	return fmt.Sprintf("%v", node.Key)
+	return hex.EncodeToString(node.Key[:16]) + "..."
 }
 
 func output(node *Node, prefix string, isTail bool, str *string) {
@@ -481,6 +491,119 @@ func (tree *Tree) deleteCase6(node *Node) {
 	}
 }
 
+func (tree *Tree) Marshal(w io.Writer) (err error) {
+	tree.Lock()
+	defer tree.Unlock()
+
+	err = binary.Write(w, o, uint64(0x617979797979790A))
+	if err != nil { return err }
+
+	err = marshal(tree.Root, w)
+	if err != nil { return err }
+
+	err = binary.Write(w, o, uint64(0x6C6D616F6F6F6F0A))
+	if err != nil { return err }
+
+	return nil
+}
+
+func marshal(n *Node, w io.Writer) (err error) {
+	if n == nil {
+		err = binary.Write(w, o, uint64(0x796565656565740A))
+		return err
+	}
+
+	err = binary.Write(w, o, uint64(0xF09F85B1EFB88F0A))
+	if err != nil { return err }
+
+	_, err = w.Write(n.Key[:])
+	if err != nil { return err }
+
+	var colorI uint64
+	if n.color {
+		colorI = 0x7468652D6579657C
+	} else {
+		colorI = 0x6865782B7465727C
+	}
+
+	err = binary.Write(w, o, colorI)
+	if err != nil { return err }
+
+	err = marshal(n.Left, w)
+	if err != nil { return err }
+
+	err = marshal(n.Right, w)
+	if err != nil { return err }
+
+	return nil
+}
+
+func (tree *Tree) Unmarshal(r io.Reader) (err error) {
+	tree.Lock()
+	defer tree.Unlock()
+
+	var sof uint64
+	err = binary.Read(r, o, &sof)
+	if err != nil { return err }
+	if sof != 0x617979797979790A {
+		return fmt.Errorf("redblack: wrong format")
+	}
+
+	tree.Root, tree.size, err = unmarshal(r)
+	if err != nil { return err }
+
+	var eof uint64
+	err = binary.Read(r, o, &eof)
+	if err != nil { return err }
+	if eof != 0x6C6D616F6F6F6F0A {
+		return fmt.Errorf("redblack: end of file missing")
+	}
+
+	return nil
+}
+
+func unmarshal(r io.Reader) (n *Node, size int, err error) {
+	var head uint64
+	err = binary.Read(r, o, &head)
+	if err != nil { return nil, 0, err }
+
+	size = 1
+
+	switch head {
+	case 0x796565656565740A:
+		return nil, 0, nil
+	case 0xF09F85B1EFB88F0A:
+		n = new(Node)
+
+		_, err = io.ReadFull(r, n.Key[:])
+		if err != nil { return nil, 0, err }
+
+		var colorInt uint64
+		err = binary.Read(r, o, &colorInt)
+		if err != nil { return nil, 0, err }
+		switch colorInt {
+		case 0x7468652D6579657C:
+			n.color = true
+		case 0x6865782B7465727C:
+			n.color = false
+		default:
+			return nil, 0, fmt.Errorf("redblack: corrupt node color")
+		}
+	default:
+		return nil, 0, fmt.Errorf("redblack: corrupt node info")
+	}
+
+	var s2 int
+	n.Left, s2, err = unmarshal(r)
+	size += s2
+	if err != nil { return nil, 0, err }
+	n.Right, s2, err = unmarshal(r)
+	size += s2
+	if err != nil { return nil, 0, err }
+
+	return n, size, nil
+}
+
 func nodeColor(node *Node) color {
 	if node == nil {
 		return black

ds/redblackhash/redblack_test.go

@@ -0,0 +1,47 @@
+package redblackhash
+
+import (
+	"bytes"
+	"math/rand"
+	"testing"
+)
+
+func TestTree_Marshal(t *testing.T) {
+	var t1, t2 Tree
+
+	// Generate 1000 random values to insert
+	for i := 0; i < 1000; i++ {
+		var key Key
+		rand.Read(key[:])
+		t1.Put(&key)
+	}
+
+	// Marshal tree
+	var wr bytes.Buffer
+	err := t1.Marshal(&wr)
+	if err != nil {
+		t.Error(err)
+		t.FailNow()
+	}
+
+	buf := wr.Bytes()
+	rd := bytes.NewBuffer(buf)
+
+	// Unmarshal tree
+	err = t2.Unmarshal(rd)
+	if err != nil {
+		t.Error(err)
+		t.FailNow()
+	}
+
+	if !compare(t1.Root, t2.Root) {
+		t.Error("trees are not equal")
+		t.FailNow()
+	}
+}
+
+func compare(n1, n2 *Node) bool {
+	return n1.Key.Compare(&n2.Key) == 0 &&
+		(n1.Left == nil || compare(n1.Left, n2.Left)) &&
+		(n1.Right == nil || compare(n1.Right, n2.Right))
+}

errors.go

@@ -3,6 +3,8 @@ package main
 import (
 	"errors"
 	"fmt"
+	"github.com/valyala/fasthttp"
+	"net"
 )
 
 var ErrRateLimit = errors.New("too many requests")
@@ -15,3 +17,29 @@ type HttpError struct {
 func (e HttpError) Error() string {
 	return fmt.Sprintf("http status %d", e.code)
 }
+
+func shouldRetry(err error) bool {
+	// HTTP errors
+	if httpErr, ok := err.(*HttpError); ok {
+		switch httpErr.code {
+		case fasthttp.StatusTooManyRequests:
+			return true
+		default:
+			// Don't retry HTTP error codes
+			return false
+		}
+	}
+
+	if dnsError, ok := err.(*net.DNSError); ok {
+		// Don't retry permanent DNS errors
+		return dnsError.IsTemporary
+	}
+
+	if netErr, ok := err.(*net.OpError); ok {
+		// Don't retry permanent network errors
+		return netErr.Temporary()
+	}
+
+	// Retry by default
+	return true
+}

go.mod

@@ -0,0 +1,14 @@
+module github.com/syndtr/od-database-crawler
+
+require (
+	github.com/beeker1121/goque v2.0.1+incompatible
+	github.com/golang/snappy v0.0.0-20180518054509-2e65f85255db // indirect
+	github.com/sirupsen/logrus v1.3.0
+	github.com/spf13/cobra v0.0.3
+	github.com/spf13/viper v1.3.1
+	github.com/syndtr/goleveldb v0.0.0-20181128100959-b001fa50d6b2 // indirect
+	github.com/terorie/od-database-crawler v1.1.1
+	github.com/valyala/fasthttp v1.1.0
+	golang.org/x/crypto v0.0.0-20190131182504-b8fe1690c613
+	golang.org/x/net v0.0.0-20180911220305-26e67e76b6c3
+)

go.sum

@@ -0,0 +1,66 @@
+github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
+github.com/beeker1121/goque v2.0.1+incompatible h1:5nJHPMqQLxUvGFc8m/NW2QzxKyc0zICmqs/JUsmEjwE=
+github.com/beeker1121/goque v2.0.1+incompatible/go.mod h1:L6dOWBhDOnxUVQsb0wkLve0VCnt2xJW/MI8pdRX4ANw=
+github.com/coreos/etcd v3.3.10+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=
+github.com/coreos/go-etcd v2.0.0+incompatible/go.mod h1:Jez6KQU2B/sWsbdaef3ED8NzMklzPG4d5KIOhIy30Tk=
+github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
+github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
+github.com/golang/snappy v0.0.0-20180518054509-2e65f85255db h1:woRePGFeVFfLKN/pOkfl+p/TAqKOfFu+7KPlMVpok/w=
+github.com/golang/snappy v0.0.0-20180518054509-2e65f85255db/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
+github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4=
+github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
+github.com/klauspost/compress v1.4.0 h1:8nsMz3tWa9SWWPL60G1V6CUsf4lLjWLTNEtibhe8gh8=
+github.com/klauspost/compress v1.4.0/go.mod h1:RyIbtBH6LamlWaDj8nUwkbUhJ87Yi3uG0guNDohfE1A=
+github.com/klauspost/cpuid v0.0.0-20180405133222-e7e905edc00e h1:+lIPJOWl+jSiJOc70QXJ07+2eg2Jy2EC7Mi11BWujeM=
+github.com/klauspost/cpuid v0.0.0-20180405133222-e7e905edc00e/go.mod h1:Pj4uuM528wm8OyEC2QMXAi2YiTZ96dNQPGgoMS4s3ek=
+github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
+github.com/magiconair/properties v1.8.0 h1:LLgXmsheXeRoUOBOjtwPQCWIYqM/LU1ayDtDePerRcY=
+github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
+github.com/mitchellh/mapstructure v1.1.2 h1:fmNYVwqnSfB9mZU6OS2O6GsXM+wcskZDuKQzvN1EDeE=
+github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
+github.com/pelletier/go-toml v1.2.0 h1:T5zMGML61Wp+FlcbWjRDT7yAxhJNAiPPLOFECq181zc=
+github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/sirupsen/logrus v1.3.0 h1:hI/7Q+DtNZ2kINb6qt/lS+IyXnHQe9e90POfeewL/ME=
+github.com/sirupsen/logrus v1.3.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
+github.com/spf13/afero v1.1.2 h1:m8/z1t7/fwjysjQRYbP0RD+bUIF/8tJwPdEZsI83ACI=
+github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
+github.com/spf13/cast v1.3.0 h1:oget//CVOEoFewqQxwr0Ej5yjygnqGkvggSE/gB35Q8=
+github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
+github.com/spf13/cobra v0.0.3 h1:ZlrZ4XsMRm04Fr5pSFxBgfND2EBVa1nLpiy1stUsX/8=
+github.com/spf13/cobra v0.0.3/go.mod h1:1l0Ry5zgKvJasoi3XT1TypsSe7PqH0Sj9dhYf7v3XqQ=
+github.com/spf13/jwalterweatherman v1.0.0 h1:XHEdyB+EcvlqZamSM4ZOMGlc93t6AcsBEu9Gc1vn7yk=
+github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
+github.com/spf13/pflag v1.0.3 h1:zPAT6CGy6wXeQ7NtTnaTerfKOsV6V6F8agHXFiazDkg=
+github.com/spf13/pflag v1.0.3/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
+github.com/spf13/viper v1.3.1 h1:5+8j8FTpnFV4nEImW/ofkzEt8VoOiLXxdYIDsB73T38=
+github.com/spf13/viper v1.3.1/go.mod h1:ZiWeW+zYFKm7srdB9IoDzzZXaJaI5eL9QjNiN/DMA2s=
+github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+github.com/syndtr/goleveldb v0.0.0-20181128100959-b001fa50d6b2 h1:GnOzE5fEFN3b2zDhJJABEofdb51uMRNb8eqIVtdducs=
+github.com/syndtr/goleveldb v0.0.0-20181128100959-b001fa50d6b2/go.mod h1:Z4AUp2Km+PwemOoO/VB5AOx9XSsIItzFjoJlOSiYmn0=
+github.com/terorie/od-database-crawler v1.1.1 h1:Ca+ZqbZX3rVWBR8SDRzvroyxjBtUs75MQXZ9YG0gqGo=
+github.com/terorie/od-database-crawler v1.1.1/go.mod h1:vVJ7pLkudrlUNp9qu24JCzQ8N6mFsrOmX1tPXr155DQ=
+github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8/go.mod h1:VFNgLljTbGfSG7qAOspJ7OScBnGdDN/yBr0sguwnwf0=
+github.com/valyala/bytebufferpool v1.0.0 h1:GqA5TC/0021Y/b9FG4Oi9Mr3q7XYx6KllzawFIhcdPw=
+github.com/valyala/bytebufferpool v1.0.0/go.mod h1:6bBcMArwyJ5K/AmCkWv1jt77kVWyCJ6HpOuEn7z0Csc=
+github.com/valyala/fasthttp v1.1.0 h1:3BohG7mqwj4lq7PTX//7gLbUlzNvZSPmuHFnloXT0lw=
+github.com/valyala/fasthttp v1.1.0/go.mod h1:4vX61m6KN+xDduDNwXrhIAVZaZaZiQ1luJk8LWSxF3s=
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+github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77/go.mod h1:aYKd//L2LvnjZzWKhF00oedf4jCCReLcmhLdhm1A27Q=
+golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
+golang.org/x/crypto v0.0.0-20181203042331-505ab145d0a9/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
+golang.org/x/crypto v0.0.0-20190131182504-b8fe1690c613 h1:MQ/ZZiDsUapFFiMS+vzwXkCTeEKaum+Do5rINYJDmxc=
+golang.org/x/crypto v0.0.0-20190131182504-b8fe1690c613/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
+golang.org/x/net v0.0.0-20180911220305-26e67e76b6c3 h1:czFLhve3vsQetD6JOJ8NZZvGQIXlnN3/yXxbT6/awxI=
+golang.org/x/net v0.0.0-20180911220305-26e67e76b6c3/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20181205085412-a5c9d58dba9a h1:1n5lsVfiQW3yfsRGu98756EH1YthsFqr/5mxHduZW2A=
+golang.org/x/sys v0.0.0-20181205085412-a5c9d58dba9a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

help.go

@@ -0,0 +1,15 @@
+package main
+
+const helpText =
+`HTTP crawler for the OD-Database
+  DB      >> https://od-db.the-eye.eu <<
+  Crawler >> https://github.com/terorie/od-database-crawler <<
+  Server  >> https://github.com/simon987/od-database <<
+
+Quick start:
+ - get config file  (config.yml in working dir)
+ - get OD-DB server ("server.url": Database URL + /api)
+ - get access token ("server.token": e.g. c010b6dd-20...)
+ - ./od-database-crawler server
+
+Questions? Discord @terorie#2664 / Telegram @terorie`

main.go

@@ -2,72 +2,104 @@ package main
 
 import (
 	"context"
+	"fmt"
 	"github.com/sirupsen/logrus"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
 	"github.com/terorie/od-database-crawler/fasturl"
-	"github.com/urfave/cli"
 	"os"
+	"os/signal"
 	"strings"
 	"sync/atomic"
 	"time"
 )
 
-var app = cli.App {
-	Name:         "od-database-crawler",
-	Usage:        "OD-Database Go crawler",
-	Version:      "1.0.1",
-	BashComplete: cli.DefaultAppComplete,
-	Writer:       os.Stdout,
-	Action:       cmdBase,
-	Commands:     []cli.Command{
-		{
-			Name:      "crawl",
-			Usage:     "Crawl a list of URLs",
-			ArgsUsage: "<site>",
-			Action:    cmdCrawler,
-		},
-	},
-	After: func(i *cli.Context) error {
+var configFile string
+
+var rootCmd = cobra.Command {
+	Use: "od-database-crawler",
+	Version: "1.2.1",
+	Short: "OD-Database Go crawler",
+	Long: helpText,
+	PersistentPreRunE: preRun,
+	PersistentPostRun: func(cmd *cobra.Command, args []string) {
 		exitHooks.Execute()
-		return nil
 	},
 }
 
+var serverCmd = cobra.Command {
+	Use: "server",
+	Short: "Start crawl server",
+	Long: "Connect to the OD-Database and contribute to the database\n" +
+		"by crawling the web for open directories!",
+	Run: cmdBase,
+}
+
+var crawlCmd = cobra.Command {
+	Use: "crawl",
+	Short: "Crawl an URL",
+	Long: "Crawl the URL specified.\n" +
+		"Results will not be uploaded to the database,\n" +
+		"they're saved under crawled/0.json instead.\n" +
+		"Primarily used for testing and benchmarking.",
+	RunE: cmdCrawler,
+	Args: cobra.ExactArgs(1),
+}
+
 var exitHooks Hooks
 
 func init() {
+	rootCmd.AddCommand(&crawlCmd)
+	rootCmd.AddCommand(&serverCmd)
+
 	prepareConfig()
 }
 
-func main() {
-	err := os.MkdirAll("crawled", 0755)
-	if err != nil {
-		panic(err)
-	}
+func preRun(cmd *cobra.Command, args []string) error {
+	if err := os.MkdirAll("crawled", 0755);
+		err != nil { panic(err) }
 
-	readConfig()
-	app.Run(os.Args)
+	if err := os.MkdirAll("queue", 0755);
+		err != nil { panic(err) }
+
+	return nil
 }
 
-func cmdBase(_ *cli.Context) error {
-	// TODO Graceful shutdown
-	appCtx := context.Background()
-	forceCtx := context.Background()
+func main() {
+	err := rootCmd.Execute()
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
+
+func cmdBase(_ *cobra.Command, _ []string) {
+	onlineMode = true
+	readConfig()
+
+	appCtx, soft := context.WithCancel(context.Background())
+	forceCtx, hard := context.WithCancel(context.Background())
+	go hardShutdown(forceCtx)
+	go listenCtrlC(soft, hard)
 
 	inRemotes := make(chan *OD)
-	go Schedule(forceCtx, inRemotes)
+	go LoadResumeTasks(inRemotes)
+	go Schedule(appCtx, inRemotes)
 
 	ticker := time.NewTicker(config.Recheck)
 	defer ticker.Stop()
 	for {
 		select {
 		case <-appCtx.Done():
-			return nil
+			goto shutdown
 		case <-ticker.C:
 			t, err := FetchTask()
 			if err != nil {
 				logrus.WithError(err).
 					Error("Failed to get new task")
-				time.Sleep(30 * time.Second)
+				if !sleep(viper.GetDuration(ConfCooldown), appCtx) {
+					goto shutdown
+				}
 				continue
 			}
 			if t == nil {
@@ -94,22 +126,22 @@ func cmdBase(_ *cli.Context) error {
 			} else if err != nil {
 				logrus.WithError(err).
 					Error("Failed to get new task")
-				time.Sleep(30 * time.Second)
+				time.Sleep(viper.GetDuration(ConfCooldown))
 				continue
 			}
 			ScheduleTask(inRemotes, t, &baseUri)
 		}
 	}
 
-	return nil
+	shutdown:
+	globalWait.Wait()
 }
 
-func cmdCrawler(clic *cli.Context) error {
-	if clic.NArg() != 1 {
-		cli.ShowCommandHelpAndExit(clic, "crawl", 1)
-	}
+func cmdCrawler(_ *cobra.Command, args []string) error {
+	onlineMode = false
+	readConfig()
 
-	arg := clic.Args()[0]
+	arg := args[0]
 	// https://github.com/golang/go/issues/19779
 	if !strings.Contains(arg, "://") {
 		arg = "http://" + arg
@@ -141,3 +173,30 @@ func cmdCrawler(clic *cli.Context) error {
 
 	return nil
 }
+
+func listenCtrlC(soft, hard context.CancelFunc) {
+	c := make(chan os.Signal)
+	signal.Notify(c, os.Interrupt)
+
+	<-c
+	logrus.Info(">>> Shutting down crawler... <<<")
+	soft()
+
+	<-c
+	logrus.Warning(">>> Force shutdown! <<<")
+	hard()
+}
+
+func hardShutdown(c context.Context) {
+	<-c.Done()
+	os.Exit(1)
+}
+
+func sleep(d time.Duration, c context.Context) bool {
+	select {
+	case <-time.After(d):
+		return true
+	case <-c.Done():
+		return false
+	}
+}

model.go

@@ -3,7 +3,6 @@ package main
 import (
 	"github.com/terorie/od-database-crawler/ds/redblackhash"
 	"github.com/terorie/od-database-crawler/fasturl"
-	"sync"
 	"time"
 )
 
@@ -23,7 +22,6 @@ type TaskResult struct {
 }
 
 type Job struct {
-	OD        *OD
 	Uri       fasturl.URL
 	UriStr    string
 	Fails     int
@@ -31,12 +29,19 @@ type Job struct {
 }
 
 type OD struct {
-	Task    Task
-	Result  TaskResult
-	Wait    sync.WaitGroup
-	BaseUri fasturl.URL
-	WCtx    WorkerContext
-	Scanned redblackhash.Tree
+	Task       Task
+	Result     TaskResult
+	InProgress int64
+	BaseUri    fasturl.URL
+	WCtx       WorkerContext
+	Scanned    redblackhash.Tree
+}
+
+type PausedOD struct {
+	Task       *Task
+	Result     *TaskResult
+	BaseUri    *fasturl.URL
+	InProgress int64
 }
 
 type File struct {
@@ -57,3 +62,8 @@ func (o *OD) LoadOrStoreKey(k *redblackhash.Key) (exists bool) {
 	o.Scanned.Put(k)
 	return false
 }
+
+type errorString string
+func (e errorString) Error() string {
+	return string(e)
+}

queue.go

@@ -0,0 +1,129 @@
+package main
+
+import (
+	"github.com/beeker1121/goque"
+	"os"
+	"sync"
+	"sync/atomic"
+)
+
+type BufferedQueue struct {
+	dataDir string
+	q       *goque.Queue
+	buf     []Job
+	m       sync.Mutex
+}
+
+func OpenQueue(dataDir string) (bq *BufferedQueue, err error) {
+	bq = new(BufferedQueue)
+	if config.JobBufferSize < 0 {
+		return
+	}
+	bq.dataDir = dataDir
+	bq.q, err = goque.OpenQueue(dataDir)
+	if err != nil { return nil, err }
+	return
+}
+
+func (q *BufferedQueue) Enqueue(job *Job) error {
+	atomic.AddInt64(&totalQueued, 1)
+	if q.directEnqueue(job) {
+		return nil
+	}
+
+	var gob JobGob
+	gob.ToGob(job)
+	_, err := q.q.EnqueueObject(gob)
+	return err
+}
+
+func (q *BufferedQueue) Dequeue() (job Job, err error) {
+	if q.directDequeue(&job) {
+		atomic.AddInt64(&totalQueued, -1)
+		return job, nil
+	}
+
+	if config.JobBufferSize < 0 {
+		err = goque.ErrEmpty
+		return
+	}
+
+	var item *goque.Item
+	item, err = q.q.Dequeue()
+	if err != nil { return }
+
+	atomic.AddInt64(&totalQueued, -1)
+
+	var gob JobGob
+	err = item.ToObject(&gob)
+	if err != nil { return }
+	gob.FromGob(&job)
+
+	return
+}
+
+func (q *BufferedQueue) directEnqueue(job *Job) bool {
+	q.m.Lock()
+	defer q.m.Unlock()
+
+	bs := config.JobBufferSize
+	if len(q.buf) < bs || bs < 0 {
+		q.buf = append(q.buf, *job)
+		return true
+	} else {
+		return false
+	}
+}
+
+func (q *BufferedQueue) directDequeue(job *Job) bool {
+	q.m.Lock()
+	defer q.m.Unlock()
+
+	if len(q.buf) > 0 {
+		*job = q.buf[0]
+		q.buf = q.buf[1:]
+		return true
+	} else {
+		return false
+	}
+}
+
+// Always returns nil (But implements io.Closer)
+func (q *BufferedQueue) Close() error {
+	if config.JobBufferSize < 0 {
+		return nil
+	}
+
+	// Close ignoring errors
+	q.q.Close()
+
+	// Delete files
+	if err := os.RemoveAll(q.dataDir);
+		err != nil { panic(err) }
+
+	return nil
+}
+
+type JobGob struct {
+	Uri string
+	Fails int
+	LastError string
+}
+
+func (g *JobGob) ToGob(j *Job) {
+	g.Uri = j.UriStr
+	g.Fails = j.Fails
+	if j.LastError != nil {
+		g.LastError = j.LastError.Error()
+	}
+}
+
+func (g *JobGob) FromGob(j *Job) {
+	if err := j.Uri.Parse(g.Uri);
+		err != nil { panic(err) }
+	j.UriStr = g.Uri
+	j.Fails = g.Fails
+	if g.LastError != "" {
+		j.LastError = errorString(g.LastError)
+	}
+}

resume.go

@@ -0,0 +1,270 @@
+package main
+
+import (
+	"bytes"
+	"encoding/binary"
+	"encoding/gob"
+	"fmt"
+	"github.com/beeker1121/goque"
+	"github.com/sirupsen/logrus"
+	"github.com/spf13/viper"
+	"io"
+	"os"
+	"path/filepath"
+	"strconv"
+	"sync/atomic"
+	"time"
+)
+
+func init() {
+	gob.Register(&PausedOD{})
+}
+
+func LoadResumeTasks(inRemotes chan<- *OD) {
+	resumed, err := ResumeTasks()
+	if err != nil {
+		logrus.WithError(err).
+			Error("Failed to resume queued tasks. " +
+				"/queue is probably corrupt")
+		err = nil
+	}
+
+	for _, remote := range resumed {
+		inRemotes <- remote
+	}
+}
+
+func ResumeTasks() (tasks []*OD, err error) {
+	// Get files in /queue
+	var queueF *os.File
+	var entries []os.FileInfo
+	queueF, err = os.Open("queue")
+	if err != nil { return nil, err }
+	defer queueF.Close()
+	entries, err = queueF.Readdir(-1)
+	if err != nil { return nil, err }
+
+	resumeDur := viper.GetDuration(ConfResume)
+
+	for _, entry := range entries {
+		if !entry.IsDir() { continue }
+
+		// Check if name is a number
+		var id uint64
+		if id, err = strconv.ParseUint(entry.Name(), 10, 64); err != nil {
+			continue
+		}
+
+		// Too old to be resumed
+		timeDelta := time.Since(entry.ModTime())
+		if resumeDur >= 0 && timeDelta > resumeDur {
+			removeOldQueue(id)
+			continue
+		}
+
+		// Load queue
+		var od *OD
+		if od, err = resumeQueue(id); err != nil {
+			logrus.WithError(err).
+				WithField("id", id).
+				Warning("Failed to load paused task")
+			continue
+		} else if od == nil {
+			removeOldQueue(id)
+			continue
+		}
+
+		tasks = append(tasks, od)
+	}
+
+	return tasks, nil
+}
+
+func SaveTask(od *OD) (err error) {
+	dir := filepath.Join("queue",
+		strconv.FormatUint(od.Task.WebsiteId, 10))
+
+	fPath := filepath.Join(dir, "PAUSED")
+
+	err = os.Mkdir(dir, 0777)
+	if err != nil { return err }
+
+	// Open pause file
+	pausedF, err := os.OpenFile(fPath, os.O_CREATE | os.O_WRONLY | os.O_TRUNC, 0666)
+	if err != nil { return err }
+	defer pausedF.Close()
+
+	err = writePauseFile(od, pausedF)
+	if err != nil { return err }
+
+	return nil
+}
+
+func resumeQueue(id uint64) (od *OD, err error) {
+	logrus.WithField("id", id).
+		Info("Found unfinished")
+
+	fPath := filepath.Join("queue", strconv.FormatUint(id, 10))
+
+	// Try to find pause file
+	pausedF, err := os.Open(filepath.Join(fPath, "PAUSED"))
+	if os.IsNotExist(err) {
+		// No PAUSED file => not paused
+		// not paused => no error
+		return nil, nil
+	} else if err != nil {
+		return nil, err
+	}
+	defer pausedF.Close()
+
+	od = new(OD)
+	od.WCtx.OD = od
+
+	err = readPauseFile(od, pausedF)
+	if err != nil { return nil, err }
+
+	// Open queue
+	bq, err := OpenQueue(fPath)
+	if err != nil { return nil, err }
+
+	od.WCtx.Queue = bq
+
+	logrus.WithField("id", id).
+		Info("Resuming task")
+
+	return od, nil
+}
+
+func removeOldQueue(id uint64) {
+	if id == 0 {
+		// TODO Make custom crawl less of an ugly hack
+		return
+	}
+
+	logrus.WithField("id", id).
+		Warning("Deleting & returning old task")
+
+	name := strconv.FormatUint(id, 10)
+
+	fPath := filepath.Join("queue", name)
+
+	// Acquire old queue
+	q, err := goque.OpenQueue(fPath)
+	if err != nil {
+		// Queue lock exists, don't delete
+		logrus.WithField("err", err).
+			WithField("path", fPath).
+			Error("Failed to acquire old task")
+		return
+	}
+
+	// Delete old queue from disk
+	err = q.Drop()
+	if err != nil {
+		// Queue lock exists, don't delete
+		logrus.WithField("err", err).
+			WithField("path", fPath).
+			Error("Failed to delete old task")
+		return
+	}
+
+	// Delete old crawl result from disk
+	_ = os.Remove(filepath.Join("crawled", name + ".json"))
+
+	// Return task to server
+	if err := CancelTask(id); err != nil {
+		// Queue lock exists, don't delete
+		logrus.WithField("err", err).
+			WithField("id", id).
+			Warning("Failed to return unfinished task to server")
+		return
+	}
+}
+
+func writePauseFile(od *OD, w io.Writer) (err error) {
+	// Write pause file version
+	_, err = w.Write([]byte("ODPAUSE-"))
+	if err != nil { return err }
+
+	// Create save state
+	paused := PausedOD {
+		Task:       &od.Task,
+		Result:     &od.Result,
+		BaseUri:    &od.BaseUri,
+		InProgress: atomic.LoadInt64(&od.InProgress),
+	}
+
+	// Prepare pause settings
+	var b bytes.Buffer
+	pauseEnc := gob.NewEncoder(&b)
+	err = pauseEnc.Encode(&paused)
+	if err != nil { return err }
+
+	// Write length of pause settings
+	err = binary.Write(w, binary.LittleEndian, uint64(b.Len()))
+	if err != nil { return err }
+
+	// Write pause settings
+	_, err = w.Write(b.Bytes())
+	if err != nil { return err }
+
+	// Write pause scan state
+	err = od.Scanned.Marshal(w)
+	if err != nil { return err }
+
+	// Save mark
+	_, err = w.Write([]byte("--------"))
+	if err != nil { return err }
+	
+	return nil
+}
+
+func readPauseFile(od *OD, r io.Reader) (err error) {
+	// Make the paused struct point to OD fields
+	// So gob loads values into the OD struct
+	paused := PausedOD {
+		Task:       &od.Task,
+		Result:     &od.Result,
+		BaseUri:    &od.BaseUri,
+	}
+
+	var version [8]byte
+	_, err = io.ReadFull(r, version[:])
+	if err != nil { return err }
+	if !bytes.Equal(version[:], []byte("ODPAUSE-")) {
+		return fmt.Errorf("unsupported pause file")
+	}
+
+	// Read pause settings len
+	var pauseSettingsLen uint64
+	err = binary.Read(r, binary.LittleEndian, &pauseSettingsLen)
+
+	// Read pause settings
+	pauseDec := gob.NewDecoder(io.LimitReader(r, int64(pauseSettingsLen)))
+	err = pauseDec.Decode(&paused)
+	if err != nil { return err }
+	atomic.StoreInt64(&od.InProgress, paused.InProgress)
+
+	err = readPauseStateTree(od, r)
+	if err != nil {
+		return fmt.Errorf("failed to read state tree: %s", err)
+	}
+
+	return nil
+}
+
+func readPauseStateTree(od *OD, r io.Reader) (err error) {
+	// Read pause scan state
+	err = od.Scanned.Unmarshal(r)
+	if err != nil { return err }
+
+	// Check mark
+	var mark [8]byte
+	_, err = io.ReadFull(r, mark[:])
+	if err != nil { return err }
+	if !bytes.Equal(mark[:], []byte("--------")) {
+		return fmt.Errorf("corrupt pause file")
+	}
+
+	return nil
+}

resume_test.go

@@ -0,0 +1,48 @@
+package main
+
+import (
+	"bytes"
+	"github.com/terorie/od-database-crawler/fasturl"
+	"testing"
+	"time"
+)
+
+func TestResumeTasks_Empty(t *testing.T) {
+	start := time.Now().Add(-1 * time.Minute)
+	od := OD {
+		Task: Task {
+			WebsiteId: 213,
+			Url: "https://the-eye.eu/public/",
+		},
+		Result: TaskResult {
+			StartTime: start,
+			StartTimeUnix: start.Unix(),
+			EndTimeUnix: time.Now().Unix(),
+			WebsiteId: 213,
+		},
+		InProgress: 0,
+		BaseUri: fasturl.URL {
+			Scheme: fasturl.SchemeHTTPS,
+			Host: "the-eye.eu",
+			Path: "/public/",
+		},
+	}
+	od.WCtx.OD = &od
+
+	var b bytes.Buffer
+	var err error
+	err = writePauseFile(&od, &b)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	buf := b.Bytes()
+
+	var od2 OD
+
+	b2 := bytes.NewBuffer(buf)
+	err = readPauseFile(&od2, b2)
+	if err != nil {
+		t.Fatal(err)
+	}
+}

scheduler.go

@@ -16,48 +16,63 @@ import (
 var activeTasksLock sync.Mutex
 var activeTasks = make(map[uint64]bool)
 var numActiveTasks int32
-var totalBuffered int64
+var totalQueued int64
 
 func Schedule(c context.Context, remotes <-chan *OD) {
 	go Stats(c)
 
 	for remote := range remotes {
-		logrus.WithField("url", remote.BaseUri.String()).
-			Info("Starting crawler")
-
-		// Collect results
-		results := make(chan File)
-
-		// Spawn workers
-		remote.WCtx.in, remote.WCtx.out = makeJobBuffer(c)
-		for i := 0; i < config.Workers; i++ {
-			go remote.WCtx.Worker(results)
-		}
-
-		// Enqueue initial job
-		atomic.AddInt32(&numActiveTasks, 1)
-		remote.WCtx.queueJob(Job{
-			OD:     remote,
-			Uri:    remote.BaseUri,
-			UriStr: remote.BaseUri.String(),
-			Fails:  0,
-		})
-
-		// Upload result when ready
-		go remote.Watch(results)
-
-		// Sleep if max number of tasks are active
-		for atomic.LoadInt32(&numActiveTasks) > config.Tasks {
-			select {
-			case <-c.Done():
-				return
-			case <-time.After(time.Second):
-				continue
-			}
+		if !scheduleNewTask(c, remote) {
+			return
 		}
 	}
 }
 
+func scheduleNewTask(c context.Context, remote *OD) bool {
+	logrus.WithField("url", remote.BaseUri.String()).
+		Info("Starting crawler")
+
+	// Collect results
+	results := make(chan File)
+
+	remote.WCtx.OD = remote
+
+	// Get queue path
+	queuePath := path.Join("queue", fmt.Sprintf("%d", remote.Task.WebsiteId))
+
+	// Delete existing queue
+	if err := os.RemoveAll(queuePath);
+		err != nil { panic(err) }
+
+	// Start new queue
+	var err error
+	remote.WCtx.Queue, err = OpenQueue(queuePath)
+	if err != nil { panic(err) }
+
+	// Spawn workers
+	remote.WCtx.SpawnWorkers(c, results, config.Workers)
+
+	// Enqueue initial job
+	atomic.AddInt32(&numActiveTasks, 1)
+	remote.WCtx.queueJob(Job{
+		Uri:    remote.BaseUri,
+		UriStr: remote.BaseUri.String(),
+		Fails:  0,
+	})
+
+	// Upload result when ready
+	go remote.Watch(results)
+
+	// Sleep if max number of tasks are active
+	for atomic.LoadInt32(&numActiveTasks) > config.Tasks {
+		if !sleep(time.Second, c) {
+			break
+		}
+	}
+
+	return true
+}
+
 func ScheduleTask(remotes chan<- *OD, t *Task, u *fasturl.URL) {
 	if !t.register() {
 		return
@@ -105,7 +120,7 @@ func (o *OD) Watch(results chan File) {
 	// Open crawl results file
 	f, err := os.OpenFile(
 		filePath,
-		os.O_CREATE | os.O_RDWR | os.O_TRUNC,
+		os.O_CREATE | os.O_RDWR | os.O_APPEND,
 		0644,
 	)
 	if err != nil {
@@ -147,12 +162,33 @@ func (o *OD) handleCollect(results chan File, f *os.File, collectErrC chan error
 	defer close(results)
 
 	// Wait for all jobs on remote to finish
-	o.Wait.Wait()
-	close(o.WCtx.in)
-	atomic.AddInt32(&numActiveTasks, -1)
+	for {
+		// Natural finish
+		if atomic.LoadInt64(&o.InProgress) == 0 {
+			o.onTaskFinished()
+			return
+		}
+		// Abort
+		if atomic.LoadInt32(&o.WCtx.aborted) != 0 {
+			// Wait for all workers to finish
+			o.WCtx.workers.Wait()
+			o.onTaskPaused()
+			return
+		}
+
+		time.Sleep(500 * time.Millisecond)
+	}
+}
+
+func (o *OD) onTaskFinished() {
+	defer atomic.AddInt32(&numActiveTasks, -1)
+
+	// Close queue
+	if err := o.WCtx.Queue.Close(); err != nil {
+		panic(err)
+	}
 
 	// Log finish
-
 	logrus.WithFields(logrus.Fields{
 		"id":  o.Task.WebsiteId,
 		"url": o.BaseUri.String(),
@@ -175,6 +211,37 @@ func (o *OD) handleCollect(results chan File, f *os.File, collectErrC chan error
 	}
 }
 
+func (o *OD) onTaskPaused() {
+	defer atomic.AddInt32(&numActiveTasks, -1)
+
+	// Close queue
+	if err := o.WCtx.Queue.Close(); err != nil {
+		panic(err)
+	}
+
+	// Set current end time
+	o.Result.EndTimeUnix = time.Now().Unix()
+
+	// Save task metadata
+	err := SaveTask(o)
+	if err != nil {
+		// Log finish
+		logrus.WithFields(logrus.Fields{
+			"err": err.Error(),
+			"id":  o.Task.WebsiteId,
+			"url": o.BaseUri.String(),
+		}).Error("Failed to save crawler state")
+		return
+	}
+
+	// Log finish
+	logrus.WithFields(logrus.Fields{
+		"id":  o.Task.WebsiteId,
+		"url": o.BaseUri.String(),
+		"duration": time.Since(o.Result.StartTime),
+	}).Info("Crawler paused")
+}
+
 func (t *Task) Collect(results chan File, f *os.File, errC chan<- error) {
 	err := t.collect(results, f)
 	if err != nil {
@@ -198,51 +265,3 @@ func (t *Task) collect(results chan File, f *os.File) error {
 
 	return nil
 }
-
-func makeJobBuffer(c context.Context) (chan<- Job, <-chan Job) {
-	in  := make(chan Job)
-	out := make(chan Job)
-	go bufferJobs(c, in, out)
-	return in, out
-}
-
-func bufferJobs(c context.Context, in chan Job, out chan Job) {
-	defer close(out)
-	var inQueue []Job
-	outCh := func() chan Job {
-		if len(inQueue) == 0 {
-			return nil
-		}
-		return out
-	}
-	for len(inQueue) > 0 || in != nil {
-		if len(inQueue) == 0 {
-			select {
-			case v, ok := <-in:
-				if !ok {
-					in = nil
-				} else {
-					atomic.AddInt64(&totalBuffered, 1)
-					inQueue = append(inQueue, v)
-				}
-			case <-c.Done():
-				return
-			}
-		} else {
-			select {
-			case v, ok := <-in:
-				if !ok {
-					in = nil
-				} else {
-					atomic.AddInt64(&totalBuffered, 1)
-					inQueue = append(inQueue, v)
-				}
-			case outCh() <- inQueue[0]:
-				atomic.AddInt64(&totalBuffered, -1)
-				inQueue = inQueue[1:]
-			case <-c.Done():
-				return
-			}
-		}
-	}
-}

server.go

@@ -5,18 +5,23 @@ import (
 	"encoding/json"
 	"fmt"
 	"github.com/sirupsen/logrus"
+	"github.com/spf13/viper"
 	"io"
 	"mime/multipart"
 	"net/http"
 	"net/url"
 	"os"
 	"strconv"
+	"time"
 )
 
 var serverClient = http.Client {
 	Timeout: config.ServerTimeout,
+	Transport: new(ServerTripper),
 }
 
+var serverUserAgent = "od-database-crawler/" + rootCmd.Version
+
 func FetchTask() (t *Task, err error) {
 	res, err := serverClient.PostForm(
 		config.ServerUrl + "/task/get",
@@ -101,25 +106,37 @@ func uploadChunks(websiteId uint64, f *os.File) error {
 
 		multi.Close()
 
-		req, err := http.NewRequest(
-			http.MethodPost,
-			config.ServerUrl + "/task/upload",
-			&b)
-		req.Header.Set("content-type", multi.FormDataContentType())
-		if err != nil { return err }
+		for retries := 0; retries < viper.GetInt(ConfUploadRetries); retries++ {
+			if retries > 0 {
+				// Error occurred, retry upload
+				time.Sleep(viper.GetDuration(ConfUploadRetryInterval))
+			}
 
-		res, err := serverClient.Do(req)
-		if err != nil { return err }
-		res.Body.Close()
+			req, err := http.NewRequest(
+				http.MethodPost,
+				config.ServerUrl + "/task/upload",
+				&b)
+			req.Header.Set("content-type", multi.FormDataContentType())
+			if err != nil { continue }
 
-		if res.StatusCode != http.StatusOK {
-			return fmt.Errorf("failed to upload list part %d: %s",
-				iter, res.Status)
+			res, err := serverClient.Do(req)
+			if err != nil { continue }
+			res.Body.Close()
+
+			if res.StatusCode != http.StatusOK {
+				logrus.WithField("status", res.Status).
+					WithField("part", iter).
+					Errorf("Upload failed")
+				continue
+			}
+
+			// Upload successful
+			break
 		}
 
 		logrus.WithField("id", websiteId).
 			WithField("part", iter).
-			Infof("Uploading files chunk")
+			Infof("Uploaded files chunk")
 	}
 	return nil
 }
@@ -162,3 +179,10 @@ func CancelTask(websiteId uint64) (err error) {
 
 	return
 }
+
+type ServerTripper struct{}
+
+func (t *ServerTripper) RoundTrip(req *http.Request) (res *http.Response, err error) {
+	req.Header.Set("User-Agent", serverUserAgent)
+	return http.DefaultTransport.RoundTrip(req)
+}

stats.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"github.com/sirupsen/logrus"
+	"github.com/spf13/viper"
 	"math"
 	"runtime"
 	"sync/atomic"
@@ -19,11 +20,14 @@ func Stats(c context.Context) {
 	var crawlTicker <-chan time.Time
 	var allocTicker <-chan time.Time
 
-	if config.CrawlStats != 0 {
-		crawlTicker = time.NewTicker(config.CrawlStats).C
+	crawlInterval := viper.GetDuration(ConfCrawlStats)
+	allocInterval := viper.GetDuration(ConfAllocStats)
+
+	if crawlInterval != 0 {
+		crawlTicker = time.Tick(crawlInterval)
 	}
-	if config.AllocStats != 0 {
-		allocTicker = time.NewTicker(config.AllocStats).C
+	if allocInterval != 0 {
+		allocTicker = time.Tick(allocInterval)
 	}
 
 	for {
@@ -32,7 +36,7 @@ func Stats(c context.Context) {
 			startedNow := atomic.LoadUint64(&totalStarted)
 
 			perSecond := float64(startedNow - startedLast) /
-				config.CrawlStats.Seconds()
+				crawlInterval.Seconds()
 
 			// Round to .5
 			perSecond *= 2
@@ -57,7 +61,7 @@ func Stats(c context.Context) {
 			runtime.ReadMemStats(&mem)
 
 			logrus.WithFields(logrus.Fields{
-				"queue_count": atomic.LoadInt64(&totalBuffered),
+				"queue_count": atomic.LoadInt64(&totalQueued),
 				"heap": FormatByteCount(mem.Alloc),
 				"objects": mem.HeapObjects,
 				"num_gc": mem.NumGC,

worker.go

@@ -1,8 +1,9 @@
 package main
 
 import (
+	"context"
+	"github.com/beeker1121/goque"
 	"github.com/sirupsen/logrus"
-	"github.com/valyala/fasthttp"
 	"math"
 	"sort"
 	"strings"
@@ -14,24 +15,57 @@ import (
 var globalWait sync.WaitGroup
 
 type WorkerContext struct {
-	in chan<- Job
-	out <-chan Job
+	OD *OD
+	Queue *BufferedQueue
 	lastRateLimit time.Time
 	numRateLimits int
+	workers sync.WaitGroup
+	aborted int32
 }
 
-func (w WorkerContext) Worker(results chan<- File) {
-	for job := range w.out {
-		w.step(results, job)
+func (w *WorkerContext) SpawnWorkers(c context.Context, results chan<- File, n int) {
+	w.workers.Add(n)
+	for i := 0; i < n; i++ {
+		go w.Worker(c, results)
 	}
 }
 
-func (w WorkerContext) step(results chan<- File, job Job) {
-	defer w.finishJob(&job)
+func (w *WorkerContext) Worker(c context.Context, results chan<- File) {
+	defer w.workers.Done()
+
+	for {
+		select {
+		case <-c.Done():
+			// Not yet done
+			atomic.StoreInt32(&w.aborted, 1)
+			return
+		default:
+		}
+
+		job, err := w.Queue.Dequeue()
+		switch err {
+		case goque.ErrEmpty:
+			time.Sleep(500 * time.Millisecond)
+			continue
+
+		case goque.ErrDBClosed:
+			return
+
+		case nil:
+			w.step(results, job)
+
+		default:
+			panic(err)
+		}
+	}
+}
+
+func (w *WorkerContext) step(results chan<- File, job Job) {
+	defer w.finishJob()
 
 	var f File
 
-	newJobs, err := DoJob(&job, &f)
+	newJobs, err := w.DoJob(&job, &f)
 	atomic.AddUint64(&totalStarted, 1)
 	if err == ErrKnown {
 		return
@@ -40,14 +74,12 @@ func (w WorkerContext) step(results chan<- File, job Job) {
 	if err != nil {
 		job.Fails++
 
-		if httpErr, ok := err.(*HttpError); ok {
-			switch httpErr.code {
-			case fasthttp.StatusTooManyRequests:
-				err = ErrRateLimit
-			default:
-				// Don't retry HTTP error codes
-				return
-			}
+		if !shouldRetry(err) {
+			atomic.AddUint64(&totalAborted, 1)
+			logrus.WithField("url", job.UriStr).
+				WithError(err).
+				Error("Giving up after failure")
+			return
 		}
 
 		if job.Fails > config.Retries {
@@ -75,7 +107,7 @@ func (w WorkerContext) step(results chan<- File, job Job) {
 	}
 }
 
-func DoJob(job *Job, f *File) (newJobs []Job, err error) {
+func (w *WorkerContext) DoJob(job *Job, f *File) (newJobs []Job, err error) {
 	if len(job.Uri.Path) == 0 { return }
 	if job.Uri.Path[len(job.Uri.Path)-1] == '/' {
 		// Load directory
@@ -93,7 +125,7 @@ func DoJob(job *Job, f *File) (newJobs []Job, err error) {
 		hash := f.HashDir(links)
 
 		// Skip symlinked dirs
-		if job.OD.LoadOrStoreKey(&hash) {
+		if w.OD.LoadOrStoreKey(&hash) {
 			return nil, ErrKnown
 		}
 
@@ -114,7 +146,6 @@ func DoJob(job *Job, f *File) (newJobs []Job, err error) {
 			lastLink = uriStr
 
 			newJobs = append(newJobs, Job{
-				OD:     job.OD,
 				Uri:    link,
 				UriStr: uriStr,
 				Fails:  0,
@@ -139,13 +170,13 @@ func DoJob(job *Job, f *File) (newJobs []Job, err error) {
 			}
 			return nil, err
 		}
-		atomic.AddUint64(&job.OD.Result.FileCount, 1)
+		atomic.AddUint64(&w.OD.Result.FileCount, 1)
 	}
 	return
 }
 
-func (w WorkerContext) queueJob(job Job) {
-	job.OD.Wait.Add(1)
+func (w *WorkerContext) queueJob(job Job) {
+	atomic.AddInt64(&w.OD.InProgress, 1)
 
 	if w.numRateLimits > 0 {
 		if time.Since(w.lastRateLimit) > 5 * time.Second {
@@ -156,11 +187,13 @@ func (w WorkerContext) queueJob(job Job) {
 		}
 	}
 
-	w.in <- job
+	if err := w.Queue.Enqueue(&job); err != nil {
+		panic(err)
+	}
 }
 
-func (w WorkerContext) finishJob(job *Job) {
-	job.OD.Wait.Done()
+func (w *WorkerContext) finishJob() {
+	atomic.AddInt64(&w.OD.InProgress, -1)
 }
 
 func isErrSilent(err error) bool {