tt

   1 #! /usr/bin/env racket
   2 ; vim: filetype=racket
   3
   4 ; TODO optional text wrap
   5 ; TODO write
   6 ; TODO caching (use cache by default, unless explicitly asked for update)
   7 ; TODO timeline limits
   8 ; TODO feed set operations (perhaps better done externally?)
   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 parse "following" from feed
  14 ; - following = <nick> <uri>
  15 ; TODO parse mentions:
  16 ; - @<source.nick source.url> | @<source.url>
  17 ; TODO highlight mentions
  18 ; TODO filter on mentions
  19 ; TODO highlight hashtags
  20 ; TODO filter on hashtags
  21 ; TODO hashtags as channels? initial hashtag special?
  22 ; TODO query language
  23 ; TODO console logger colors by level ('error)
  24 ; TODO file logger ('debug)
  25 ; TODO commands:
  26 ; - r | read
  27 ;   - see timeline ops above
  28 ; - w | write
  29 ;   - arg or stdin
  30 ;   - nick expand to URI
  31 ; - q | query
  32 ;   - see timeline ops above
  33 ;   - see hashtag and channels above
  34 ; - d | download
  35 ; - u | upload
  36 ;   - calls user-configured command to upload user's own feed file to their server
  37
  38 #lang racket
  39
  40 (require racket/date)
  41
  42 (require http-client)
  43 (require rfc3339-old)
  44
  45 (struct msg  (ts_epoch ts_rfc3339 nick uri text))
  46 (struct feed (nick uri))
  47
  48 (define (concurrent-filter-map num_workers f xs)
  49   ; TODO switch from mailboxes to channels
  50   (define (make-worker id f)
  51     (define parent (current-thread))
  52     (λ ()
  53        (define self (current-thread))
  54        (define (work)
  55          (thread-send parent (cons 'next self))
  56          (match (thread-receive)
  57            ['done          (thread-send parent (cons 'exit id))]
  58            [(cons 'unit x) (begin
  59                              (define y (f x))
  60                              (when y (thread-send parent (cons 'result y)))
  61                              (work))]))
  62        (work)))
  63   (define (dispatch ws xs ys)
  64     (if (empty? ws)
  65       ys
  66       (match (thread-receive)
  67         [(cons 'exit w)   (dispatch (remove w ws =) xs ys)]
  68         [(cons 'result y) (dispatch ws xs (cons y ys))]
  69         [(cons 'next thd) (match xs
  70                             ['()         (begin
  71                                            (thread-send thd 'done)
  72                                            (dispatch ws xs ys))]
  73                             [(cons x xs) (begin
  74                                            (thread-send thd (cons 'unit x))
  75                                            (dispatch ws xs ys))])])))
  76   (define workers
  77     (range 1 (add1 num_workers)))
  78   (define threads
  79     (map (λ (id) (thread (make-worker id f))) workers))
  80   (define results
  81     (dispatch workers xs '()))
  82   (for-each thread-wait threads)
  83   results)
  84
  85 (define (msg-print out-format odd msg)
  86   (printf
  87     (match out-format
  88       ['single-line "~a  \033[1;37m<~a ~a>\033[0m  \033[0;~am~a\033[0m~n"]
  89       ['multi-line  "~a~n\033[1;37m<~a ~a>\033[0m~n\033[0;~am~a\033[0m~n~n"]
  90       [_           (raise (format "Invalid output format: ~a" out-format))])
  91     (date->string (seconds->date [msg-ts_epoch msg]) #t)
  92     (msg-nick msg)
  93     (msg-uri  msg)
  94     (if odd 36 33)
  95     (msg-text msg)))
  96
  97 (define re-msg-begin
  98   ; TODO Zulu offset. Maybe in several formats. Which ones?
  99   (pregexp "^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}"))
 100
 101 (define (str->msg nick uri str)
 102   (if (not (regexp-match? re-msg-begin str))
 103     (begin
 104       (log-debug "Non-msg line from nick:~a, line:~a" nick str)
 105       #f)
 106     (let ([toks (string-split str (regexp "\t+"))])
 107       (if (not (= 2 (length toks)))
 108         (begin
 109           (log-warning "Invalid msg line from nick:~a, msg:~a" nick str)
 110           #f)
 111         (let*
 112           ([ts_rfc3339 (first  toks)]
 113            [text       (second toks)]
 114            [t          (string->rfc3339-record ts_rfc3339)]
 115            ; TODO handle tz offset
 116            [ts_epoch (find-seconds [rfc3339-record:second t]
 117                                    [rfc3339-record:minute t]
 118                                    [rfc3339-record:hour   t]
 119                                    [rfc3339-record:mday   t]
 120                                    [rfc3339-record:month  t]
 121                                    [rfc3339-record:year   t])])
 122           (msg ts_epoch ts_rfc3339 nick uri text))))))
 123
 124 (define (str->lines str)
 125   (string-split str (regexp "[\r\n]+")))
 126
 127 (define (str->msgs nick uri str)
 128   (filter-map (λ (line) (str->msg nick uri line)) (str->lines str)))
 129
 130 (define (uri-fetch uri)
 131   (log-info "GET ~a" uri)
 132   (define resp (http-get uri))
 133   (define status (http-response-code resp))
 134   (define body (http-response-body resp))
 135   (log-debug "finished GET ~a status:~a  body length:~a"
 136              uri status (string-length body))
 137   ; TODO Handle redirects
 138   (if (= status 200) body (raise status)))
 139
 140 (define (timeline-print out-format timeline)
 141   (for ([msg timeline]
 142         [i   (in-naturals)])
 143     (msg-print out-format (odd? i) msg)))
 144
 145 (define (feed->msgs feed)
 146   (log-info "downloading feed nick:~a uri:~a"
 147             (feed-nick feed)
 148             (feed-uri feed))
 149   (with-handlers
 150     ([exn:fail:network?
 151        (λ (e)
 152           (log-error "network error nick:~a uri:~a  exn:~a"
 153                      (feed-nick feed)
 154                      (feed-uri feed)
 155                      e)
 156           #f)]
 157      [integer?
 158        (λ (status)
 159           (log-error "http error nick:~a uri:~a  status:~a"
 160                      (feed-nick feed)
 161                      (feed-uri feed)
 162                      status)
 163           #f)])
 164     (define uri (feed-uri feed))
 165     (str->msgs [feed-nick feed] uri [uri-fetch uri])))
 166
 167 ; TODO timeline contract : time-sorted list of messages
 168 (define (timeline num_workers feeds)
 169   (sort (append* (concurrent-filter-map num_workers feed->msgs feeds))
 170         (λ (a b) [< (msg-ts_epoch a) (msg-ts_epoch b)])))
 171
 172 (define (str->feed str)
 173   ; TODO validation
 174   (define toks (string-split str))
 175   (apply feed toks))
 176
 177 (define (str->feeds str)
 178   (map str->feed (str->lines str)))
 179
 180 (define (file->feeds filename)
 181   (str->feeds (file->string filename)))
 182
 183 (define (we-are-twtxt)
 184   (define uri
 185     "https://raw.githubusercontent.com/mdom/we-are-twtxt/master/we-are-twtxt.txt")
 186   (str->feeds (uri-fetch uri)))
 187
 188 (define (setup-logging)
 189   (define logger (make-logger #f #f 'debug #f))
 190   (define log-chan (make-log-receiver logger 'debug))
 191   (void (thread (λ ()
 192                    [date-display-format 'iso-8601]
 193                    [let loop ()
 194                      (define data  (sync log-chan))
 195                      (define level (vector-ref data 0))
 196                      (define msg   (vector-ref data 1))
 197                      (define ts    (date->string (current-date) #t))
 198                      (eprintf "~a [~a] ~a~n" ts level msg)
 199                      (loop)])))
 200   (current-logger logger))
 201
 202 (define (main)
 203   (define user-agent
 204     (let*
 205       ([prog-name      "tt"]
 206        [prog-version   "0.3.1"]
 207        [user-feed-file (expand-user-path "~/twtxt-me.txt")]
 208        [user           (first (file->feeds user-feed-file))])
 209       (format "~a/~a (+~a; @~a)"
 210               prog-name
 211               prog-version
 212               (feed-uri user)
 213               (feed-nick user))))
 214
 215   (setup-logging)
 216   (current-http-response-auto #f)
 217   (current-http-user-agent user-agent)
 218   (date-display-format 'rfc2822)
 219
 220   (define args (current-command-line-arguments))
 221   (define feeds
 222     (if (vector-empty? args)
 223       (we-are-twtxt)
 224       (file->feeds (vector-ref args 0))))
 225   (define out-format 'multi-line)
 226   (define num_workers 15) ; 15 was fastest out of the tried 1, 5, 10, 15 and 20.
 227   (timeline-print out-format (timeline num_workers feeds)))
 228
 229 (main)