tt

   1 #! /usr/bin/env racket
   2 ; vim: filetype=racket
   3
   4 ; TODO write
   5 ; TODO caching (use cache by default, unless explicitly asked for update)
   6 ; TODO timeline limits
   7 ; TODO user-defined feed sets (a la twitter lists)
   8 ; TODO feed set operations
   9 ; TODO timeline as a result of a query (feed set op + filter expressions)
  10 ; TODO named timelines
  11 ; TODO CLI params
  12 ; TODO config files
  13 ; TODO highlight mentions
  14 ; TODO filter on mentions
  15 ; TODO highlight hashtags
  16 ; TODO filter on hashtags
  17 ; TODO hashtags as channels? initial hashtag special?
  18 ; TODO query language
  19 ; TODO concurrency
  20 ; TODO console logger colors by level ('error)
  21 ; TODO file logger ('debug)
  22
  23 #lang racket
  24
  25 (require racket/date)
  26
  27 (require http-client)
  28 (require rfc3339-old)
  29
  30 (struct msg  (tm_epoch tm_rfc3339 nick text))
  31 (struct feed (nick uri))
  32
  33 (define (msg-print odd m)
  34   (printf "~a \033[1;37m<~a>\033[0m \033[0;~am~a\033[0m~n"
  35           (date->string (seconds->date [msg-tm_epoch m]) #t)
  36           [msg-nick m]
  37           [if odd 36 33]
  38           [msg-text m]))
  39
  40 (define re-msg-begin
  41   ; TODO Zulu offset. Maybe in several formats. Which ones?
  42   (pregexp "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}"))
  43
  44 (define (str->msg nick str)
  45   (if (not (regexp-match? re-msg-begin str))
  46     (begin
  47       (log-debug "Non-msg line from nick:~a, line:~a" nick str)
  48       #f)
  49     (let ([toks (string-split str (regexp "\t+"))])
  50       (if (not (= 2 (length toks)))
  51         (begin
  52           (log-warning "Invalid msg line from nick:~a, msg:~a" nick str)
  53           #f)
  54         (let*
  55           ([tm_rfc3339 (list-ref toks 0)]
  56            [tok_text   (list-ref toks 1)]
  57            [t (string->rfc3339-record tm_rfc3339)]
  58            ; TODO handle tz offset
  59            [tm_epoch (find-seconds [rfc3339-record:second t]
  60                                    [rfc3339-record:minute t]
  61                                    [rfc3339-record:hour   t]
  62                                    [rfc3339-record:mday   t]
  63                                    [rfc3339-record:month  t]
  64                                    [rfc3339-record:year   t])])
  65           (msg tm_epoch tm_rfc3339 nick tok_text))))))
  66
  67 (define (str->lines str)
  68   (string-split str (regexp "[\r\n]+")))
  69
  70 (define (str->msgs nick str)
  71   (filter-map (λ (line) (str->msg nick line)) (str->lines str)))
  72
  73 (define (uri-fetch uri)
  74   (log-info "GET ~a" uri)
  75   (define resp (http-get uri))
  76   (define status (http-response-code resp))
  77   (define body (http-response-body resp))
  78   (log-debug "finished GET ~a status:~a  body length:~a"
  79              uri status (string-length body))
  80   ; TODO Handle redirects
  81   (if (= status 200) body (raise status)))
  82
  83 (define (timeline-print timeline)
  84   (for ([msg timeline]
  85         [i   (in-naturals)])
  86     (msg-print (odd? i) msg)))
  87
  88 (define (feed->msgs feed)
  89   (log-info "downloading feed nick:~a uri:~a"
  90             (feed-nick feed)
  91             (feed-uri feed))
  92   (with-handlers
  93     ([exn:fail:network?
  94        (λ (e)
  95           (log-error "network error nick:~a uri:~a  exn:~a"
  96                      (feed-nick feed)
  97                      (feed-uri feed)
  98                      e)
  99           #f)]
 100      [integer?
 101        (λ (status)
 102           (log-error "http error nick:~a uri:~a  status:~a"
 103                      (feed-nick feed)
 104                      (feed-uri feed)
 105                      status)
 106           #f)])
 107     (str->msgs [feed-nick feed] [uri-fetch (feed-uri feed)])))
 108
 109 ; TODO timeline contract : time-sorted list of messages
 110 (define (timeline feeds)
 111   (sort (append* (filter-map feed->msgs feeds))
 112         (λ (a b) [< (msg-tm_epoch a) (msg-tm_epoch b)])))
 113
 114 (define (we-are-twtxt)
 115   (let* ([uri
 116            "https://raw.githubusercontent.com/mdom/we-are-twtxt/master/we-are-twtxt.txt"]
 117          [payload
 118            (uri-fetch uri)]
 119          [lines
 120            (str->lines payload)]
 121          [feeds
 122            (map (λ (line)
 123                    (define toks (string-split line))
 124                    (feed
 125                      [list-ref toks 0]
 126                      [list-ref toks 1]))
 127                 lines)])
 128     feeds))
 129
 130 (define (setup-logging)
 131   (define logger (make-logger #f #f 'debug #f))
 132   (define log-chan (make-log-receiver logger 'debug))
 133   (void (thread (λ ()
 134                    [date-display-format 'iso-8601]
 135                    [let loop ()
 136                      (define data  (sync log-chan))
 137                      (define level (vector-ref data 0))
 138                      (define msg   (vector-ref data 1))
 139                      (define ts    (date->string (current-date) #t))
 140                      (eprintf "~a [~a] ~a~n" ts level msg)
 141                      (loop)])))
 142   (current-logger logger))
 143
 144 (define (main)
 145   (setup-logging)
 146   (current-http-response-auto #f)
 147   (current-http-user-agent "xandkar/tt 0.0.0")
 148   (date-display-format 'rfc2822)
 149
 150   (define feeds (we-are-twtxt))
 151   (timeline-print (timeline feeds)))
 152
 153 (main)