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 query language
  18 ; TODO concurrency
  19
  20 #lang racket
  21
  22 (require racket/date)
  23
  24 (require http-client)
  25 (require rfc3339-old)
  26
  27 (struct msg  (tm_epoch tm_rfc3339 nick text))
  28 (struct feed (nick uri))
  29
  30 (define (msg-print odd m)
  31   (printf "~a \033[1;37m<~a>\033[0m \033[0;~am~a\033[0m~n"
  32           (date->string (seconds->date [msg-tm_epoch m]) #t)
  33           [msg-nick m]
  34           [if odd 36 33]
  35           [msg-text m]))
  36
  37 (define re-msg-begin
  38   ; TODO Zulu offset. Maybe in several formats. Which ones?
  39   (pregexp "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}"))
  40
  41 (define (str->msg nick str)
  42   (if (not (regexp-match? re-msg-begin str))
  43     (begin
  44       (log-debug "Non-msg line from nick:~a, line:~a" nick str)
  45       #f)
  46     (let ([toks (string-split str (regexp "\t+"))])
  47       (if (not (= 2 (length toks)))
  48         (begin
  49           (log-warning "Invalid msg line from nick:~a, msg:~a" nick str)
  50           #f)
  51         (let*
  52           ([tm_rfc3339 (list-ref toks 0)]
  53            [tok_text   (list-ref toks 1)]
  54            [t (string->rfc3339-record tm_rfc3339)]
  55            ; TODO handle tz offset
  56            [tm_epoch (find-seconds [rfc3339-record:second t]
  57                                    [rfc3339-record:minute t]
  58                                    [rfc3339-record:hour   t]
  59                                    [rfc3339-record:mday   t]
  60                                    [rfc3339-record:month  t]
  61                                    [rfc3339-record:year   t])])
  62           (msg tm_epoch tm_rfc3339 nick tok_text))))))
  63
  64 (define (str->lines str)
  65   (string-split str (regexp "[\r\n]+")))
  66
  67 (define (str->msgs nick str)
  68   (filter-map (λ (line) (str->msg nick line)) (str->lines str)))
  69
  70 (define (uri-fetch uri)
  71   (log-info "GET ~a" uri)
  72   (define resp (http-get uri))
  73   (define status (http-response-code resp))
  74   (define body (http-response-body resp))
  75   (log-debug "finished GET ~a status:~a  body length:~a"
  76              uri status (string-length body))
  77   ; TODO Handle redirects
  78   (if (= status 200) body (raise status)))
  79
  80 (define (timeline-print timeline)
  81   (for ([msg timeline]
  82         [i   (in-naturals)])
  83     (msg-print (odd? i) msg)))
  84
  85 (define (timeline feeds)
  86   (let* ([timelines
  87            (filter-map
  88              (λ (feed)
  89                 (log-info "processing 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              feeds)]
 109          [timeline
 110            (append* timelines)]
 111          [timeline
 112            (sort timeline (λ (a b) [< (msg-tm_epoch a) (msg-tm_epoch b)]))])
 113     timeline))
 114
 115 (define (we-are-twtxt)
 116   (let* ([uri
 117            "https://raw.githubusercontent.com/mdom/we-are-twtxt/master/we-are-twtxt.txt"]
 118          [payload
 119            (uri-fetch uri)]
 120          [lines
 121            (str->lines payload)]
 122          [feeds
 123            (map (λ (line)
 124                    (define toks (string-split line))
 125                    (feed
 126                      [list-ref toks 0]
 127                      [list-ref toks 1]))
 128                 lines)])
 129     feeds))
 130
 131 (define (setup-logging)
 132   (define logger (make-logger #f #f 'debug #f))
 133   (define log-chan (make-log-receiver logger 'debug))
 134   (void (thread (λ ()
 135                    [date-display-format 'iso-8601]
 136                    [let loop ()
 137                      (define data  (sync log-chan))
 138                      (define level (vector-ref data 0))
 139                      (define msg   (vector-ref data 1))
 140                      (define ts    (date->string (current-date) #t))
 141                      (eprintf "~a [~a] ~a~n" ts level msg)
 142                      (loop)])))
 143   (current-logger logger))
 144
 145 (define (main)
 146   (setup-logging)
 147   (current-http-response-auto #f)
 148   (current-http-user-agent "xandkar/tt 0.0.0")
 149   (date-display-format 'rfc2822)
 150
 151   (define feeds (we-are-twtxt))
 152   (timeline-print (timeline feeds)))
 153
 154 (main)