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 ; TODO commands:
  23 ; - r | read
  24 ;   - see timeline ops above
  25 ; - w | write
  26 ;   - nick expand to URI
  27 ; - q | query
  28 ;   - see timeline ops above
  29 ;   - see hashtag and channels above
  30
  31 #lang racket
  32
  33 (require racket/date)
  34
  35 (require http-client)
  36 (require rfc3339-old)
  37
  38 (struct msg  (tm_epoch tm_rfc3339 nick text))
  39 (struct feed (nick uri))
  40
  41 (define (msg-print odd m)
  42   (printf "~a \033[1;37m<~a>\033[0m \033[0;~am~a\033[0m~n"
  43           (date->string (seconds->date [msg-tm_epoch m]) #t)
  44           [msg-nick m]
  45           [if odd 36 33]
  46           [msg-text m]))
  47
  48 (define re-msg-begin
  49   ; TODO Zulu offset. Maybe in several formats. Which ones?
  50   (pregexp "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}"))
  51
  52 (define (str->msg nick str)
  53   (if (not (regexp-match? re-msg-begin str))
  54     (begin
  55       (log-debug "Non-msg line from nick:~a, line:~a" nick str)
  56       #f)
  57     (let ([toks (string-split str (regexp "\t+"))])
  58       (if (not (= 2 (length toks)))
  59         (begin
  60           (log-warning "Invalid msg line from nick:~a, msg:~a" nick str)
  61           #f)
  62         (let*
  63           ([tm_rfc3339 (list-ref toks 0)]
  64            [tok_text   (list-ref toks 1)]
  65            [t (string->rfc3339-record tm_rfc3339)]
  66            ; TODO handle tz offset
  67            [tm_epoch (find-seconds [rfc3339-record:second t]
  68                                    [rfc3339-record:minute t]
  69                                    [rfc3339-record:hour   t]
  70                                    [rfc3339-record:mday   t]
  71                                    [rfc3339-record:month  t]
  72                                    [rfc3339-record:year   t])])
  73           (msg tm_epoch tm_rfc3339 nick tok_text))))))
  74
  75 (define (str->lines str)
  76   (string-split str (regexp "[\r\n]+")))
  77
  78 (define (str->msgs nick str)
  79   (filter-map (λ (line) (str->msg nick line)) (str->lines str)))
  80
  81 (define (uri-fetch uri)
  82   (log-info "GET ~a" uri)
  83   (define resp (http-get uri))
  84   (define status (http-response-code resp))
  85   (define body (http-response-body resp))
  86   (log-debug "finished GET ~a status:~a  body length:~a"
  87              uri status (string-length body))
  88   ; TODO Handle redirects
  89   (if (= status 200) body (raise status)))
  90
  91 (define (timeline-print timeline)
  92   (for ([msg timeline]
  93         [i   (in-naturals)])
  94     (msg-print (odd? i) msg)))
  95
  96 (define (feed->msgs feed)
  97   (log-info "downloading feed nick:~a uri:~a"
  98             (feed-nick feed)
  99             (feed-uri feed))
 100   (with-handlers
 101     ([exn:fail:network?
 102        (λ (e)
 103           (log-error "network error nick:~a uri:~a  exn:~a"
 104                      (feed-nick feed)
 105                      (feed-uri feed)
 106                      e)
 107           #f)]
 108      [integer?
 109        (λ (status)
 110           (log-error "http error nick:~a uri:~a  status:~a"
 111                      (feed-nick feed)
 112                      (feed-uri feed)
 113                      status)
 114           #f)])
 115     (str->msgs [feed-nick feed] [uri-fetch (feed-uri feed)])))
 116
 117 ; TODO timeline contract : time-sorted list of messages
 118 (define (timeline feeds)
 119   (sort (append* (filter-map feed->msgs feeds))
 120         (λ (a b) [< (msg-tm_epoch a) (msg-tm_epoch b)])))
 121
 122 (define (we-are-twtxt)
 123   (let* ([uri
 124            "https://raw.githubusercontent.com/mdom/we-are-twtxt/master/we-are-twtxt.txt"]
 125          [payload
 126            (uri-fetch uri)]
 127          [lines
 128            (str->lines payload)]
 129          [feeds
 130            (map (λ (line)
 131                    ; TODO validation
 132                    (define toks (string-split line))
 133                    (feed
 134                      [list-ref toks 0]
 135                      [list-ref toks 1]))
 136                 lines)])
 137     feeds))
 138
 139 (define (setup-logging)
 140   (define logger (make-logger #f #f 'debug #f))
 141   (define log-chan (make-log-receiver logger 'debug))
 142   (void (thread (λ ()
 143                    [date-display-format 'iso-8601]
 144                    [let loop ()
 145                      (define data  (sync log-chan))
 146                      (define level (vector-ref data 0))
 147                      (define msg   (vector-ref data 1))
 148                      (define ts    (date->string (current-date) #t))
 149                      (eprintf "~a [~a] ~a~n" ts level msg)
 150                      (loop)])))
 151   (current-logger logger))
 152
 153 (define (main)
 154   (setup-logging)
 155   (current-http-response-auto #f)
 156   (current-http-user-agent "xandkar/tt 0.0.0")
 157   (date-display-format 'rfc2822)
 158
 159   (define feeds (we-are-twtxt))
 160   (timeline-print (timeline feeds)))
 161
 162 (main)