package main // TODO: have logs go somewhere useful, like email // TODO: check if images are prebinarised and if so skip multiple binarisation import ( "errors" "flag" "fmt" "log" "os" "os/exec" "path/filepath" "regexp" "strings" "time" "rescribe.xyz/go.git/preproc" ) const usage = `Usage: bookpipeline [-v] [-t training] Watches the preprocess, ocr and analyse queues for book names. When one is found this general process is followed: - The book name is hidden from the queue, and a 'heartbeat' is started which keeps it hidden (this will time out after 2 minutes if the program is terminated) - The necessary files from bookname/ are downloaded - The files are processed - The resulting files are uploaded to bookname/ - The heartbeat is stopped - The book name is removed from the queue it was taken from, and added to the next queue for future processing ` // null writer to enable non-verbose logging to be discarded type NullWriter bool func (w NullWriter) Write(p []byte) (n int, err error) { return len(p), nil } const PauseBetweenChecks = 3 * time.Minute type Clouder interface { Init() error ListObjects(bucket string, prefix string) ([]string, error) Download(bucket string, key string, fn string) error Upload(bucket string, key string, path string) error CheckQueue(url string) (Qmsg, error) AddToQueue(url string, msg string) error DelFromQueue(url string, handle string) error QueueHeartbeat(t *time.Ticker, msgHandle string, qurl string) error } type Pipeliner interface { Clouder PreQueueId() string OCRQueueId() string AnalyseQueueId() string WIPStorageId() string Logger() *log.Logger } type Qmsg struct { Handle, Body string } func download(dl chan string, process chan string, conn Pipeliner, dir string, errc chan error) { for key := range dl { fn := filepath.Join(dir, filepath.Base(key)) err := conn.Download(conn.WIPStorageId(), key, fn) if err != nil { close(process) errc <- err return } process <- fn } close(process) } func up(c chan string, done chan bool, conn Pipeliner, bookname string, errc chan error) { for path := range c { name := filepath.Base(path) key := filepath.Join(bookname, name) err := conn.Upload(conn.WIPStorageId(), key, path) if err != nil { errc <- err return } } done <- true } func preprocess(pre chan string, up chan string, errc chan error, logger *log.Logger) { for path := range pre { logger.Println("Preprocessing", path) done, err := preproc.PreProcMulti(path, []float64{0.1, 0.2, 0.4, 0.5}, "binary", 0, true, 5, 30) if err != nil { close(up) errc <- err return } for _, p := range done { up <- p } } close(up) } func ocr(training string) func(chan string, chan string, chan error, *log.Logger) { return func (toocr chan string, up chan string, errc chan error, logger *log.Logger) { for path := range toocr { logger.Println("OCRing", path) name := strings.Replace(path, ".png", "", 1) // TODO: handle any file extension cmd := exec.Command("tesseract", "-l", training, path, name, "hocr") err := cmd.Run() if err != nil { close(up) errc <- errors.New(fmt.Sprintf("Error ocring %s: %s", path, err)) return } up <- name + ".hocr" } close(up) } } func processBook(msg Qmsg, conn Pipeliner, process func(chan string, chan string, chan error, *log.Logger), match *regexp.Regexp, fromQueue string, toQueue string) error { bookname := msg.Body t := time.NewTicker(HeartbeatTime * time.Second) go conn.QueueHeartbeat(t, msg.Handle, fromQueue) d := filepath.Join(os.TempDir(), bookname) err := os.MkdirAll(d, 0755) if err != nil { t.Stop() return errors.New(fmt.Sprintf("Failed to create directory %s: %s", d, err)) } dl := make(chan string) processc := make(chan string) upc := make(chan string) done := make(chan bool) errc := make(chan error) // these functions will do their jobs when their channels have data go download(dl, processc, conn, d, errc) go process(processc, upc, errc, conn.Logger()) go up(upc, done, conn, bookname, errc) conn.Logger().Println("Getting list of objects to download") objs, err := conn.ListObjects(conn.WIPStorageId(), bookname) if err != nil { t.Stop() _ = os.RemoveAll(d) return errors.New(fmt.Sprintf("Failed to get list of files for book %s: %s", bookname, err)) } var todl []string for _, n := range objs { if !match.MatchString(n) { conn.Logger().Println("Skipping item that doesn't match target", n) continue } todl = append(todl, n) } for _, a := range todl { dl <- a } close(dl) // wait for either the done or errc channel to be sent to select { case err = <-errc: t.Stop() _ = os.RemoveAll(d) return err case <-done: } conn.Logger().Println("Sending", bookname, "to queue") err = conn.AddToQueue(toQueue, bookname) if err != nil { t.Stop() _ = os.RemoveAll(d) return errors.New(fmt.Sprintf("Error adding to queue %s: %s", bookname, err)) } t.Stop() conn.Logger().Println("Deleting original message from queue") err = conn.DelFromQueue(fromQueue, msg.Handle) if err != nil { _ = os.RemoveAll(d) return errors.New(fmt.Sprintf("Error deleting message from queue: %s", err)) } err = os.RemoveAll(d) if err != nil { return errors.New(fmt.Sprintf("Failed to remove directory %s: %s", d, err)) } return nil } func main() { verbose := flag.Bool("v", false, "verbose") training := flag.String("t", "rescribealphav5", "tesseract training file to use") flag.Usage = func() { fmt.Fprintf(flag.CommandLine.Output(), usage) flag.PrintDefaults() } flag.Parse() var verboselog *log.Logger if *verbose { verboselog = log.New(os.Stdout, "", log.LstdFlags) } else { var n NullWriter verboselog = log.New(n, "", log.LstdFlags) } // TODO: match jpg too origPattern := regexp.MustCompile(`[0-9]{4}.png$`) // TODO: match other file naming preprocessedPattern := regexp.MustCompile(`_bin[0-9].[0-9].png$`) //ocredPattern := regexp.MustCompile(`.hocr$`) var conn Pipeliner conn = &awsConn{region: "eu-west-2", logger: verboselog} verboselog.Println("Setting up AWS session") err := conn.Init() if err != nil { log.Fatalln("Error setting up cloud connection:", err) } verboselog.Println("Finished setting up AWS session") var checkPreQueue <-chan time.Time var checkOCRQueue <-chan time.Time checkPreQueue = time.After(0) checkOCRQueue = time.After(0) for { select { case <-checkPreQueue: msg, err := conn.CheckQueue(conn.PreQueueId()) checkPreQueue = time.After(PauseBetweenChecks) if err != nil { log.Println("Error checking preprocess queue", err) continue } if msg.Handle == "" { verboselog.Println("No message received on preprocess queue, sleeping") continue } err = processBook(msg, conn, preprocess, origPattern, conn.PreQueueId(), conn.OCRQueueId()) if err != nil { log.Println("Error during preprocess", err) } case <-checkOCRQueue: msg, err := conn.CheckQueue(conn.OCRQueueId()) checkOCRQueue = time.After(PauseBetweenChecks) if err != nil { log.Println("Error checking OCR queue", err) continue } if msg.Handle == "" { verboselog.Println("No message received on OCR queue, sleeping") continue } err = processBook(msg, conn, ocr(*training), preprocessedPattern, conn.OCRQueueId(), conn.AnalyseQueueId()) if err != nil { log.Println("Error during OCR process", err) } } } }