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[dweather.git] / loop.pl
1 #!/usr/bin/perl
2 use strict;
3
4 use v5.10.1;
5
6 use Mojolicious::Lite;
7 use Serial;
8 use Mojo::IOLoop;
9 use Mojo::IOLoop::Stream;
10 use Mojo::Transaction::WebSocket;
11 #use Mojo::JSON  qw(decode_json encode_json);
12 use JSON;
13 use Debug;
14 use SMGLog;
15 use Math::Round qw(nearest);
16
17 use constant pi => 3.14159265358979; 
18
19 my $devname = "/dev/davis";
20 my $datafn = ".loop_data";
21 my $dataf;
22
23 my $poll_interval = 2.5;
24 my $rain_mult = 0.2;                            # 0.1 or 0.2 mm or 0.01 inches
25 my $tid;
26 my $rid;
27 our $did;
28 my $nlcount;
29 my $state = "ready";
30 my $buf;
31 my $dbg;
32 my $ser;                                                        # the serial port Mojo::IOLoop::Stream
33
34 our $json = JSON->new->canonical(1);
35
36 our $ld = {};
37
38 our $loop_count;                                # how many LOOPs we have done, used as start indicator
39
40 our     @crc_table = (
41                                   0x0, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
42                                   0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
43                                   0x1231, 0x210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
44                                   0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
45                                   0x2462, 0x3443, 0x420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
46                                   0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
47                                   0x3653, 0x2672, 0x1611, 0x630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
48                                   0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
49                                   0x48c4, 0x58e5, 0x6886, 0x78a7, 0x840, 0x1861, 0x2802, 0x3823,
50                                   0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
51                                   0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0xa50, 0x3a33, 0x2a12,
52                                   0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
53                                   0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0xc60, 0x1c41,
54                                   0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
55                                   0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0xe70,
56                                   0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
57                                   0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
58                                   0x1080, 0xa1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
59                                   0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
60                                   0x2b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
61                                   0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
62                                   0x34e2, 0x24c3, 0x14a0, 0x481, 0x7466, 0x6447, 0x5424, 0x4405,
63                                   0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
64                                   0x26d3, 0x36f2, 0x691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
65                                   0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
66                                   0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x8e1, 0x3882, 0x28a3,
67                                   0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
68                                   0x4a75, 0x5a54, 0x6a37, 0x7a16, 0xaf1, 0x1ad0, 0x2ab3, 0x3a92,
69                                   0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
70                                   0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0xcc1,
71                                   0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
72                                   0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0xed1, 0x1ef0
73                                  );
74
75 our %bar_trend;
76
77 $bar_trend{-60} = "Falling Rapidly";
78 $bar_trend{196} = "Falling Rapidly";
79 $bar_trend{-20} = "Falling Slowly";
80 $bar_trend{236} = "Falling Slowly";
81 $bar_trend{0} = "Steady";
82 $bar_trend{20} = "Rising Slowly";
83 $bar_trend{60} = "Rising Rapidly";
84
85 our $ending = 0;
86
87 $SIG{TERM} = $SIG{INT} = sub {++$ending; Mojo::IOLoop->stop;};
88 $SIG{HUP} = 'IGNORE';
89
90
91 get '/' => 'index';
92
93 # WebSocket weather service
94 websocket '/index' => sub {
95   my $c = shift;
96  
97   # Opened
98   $c->app->log->debug('WebSocket opened.');
99   dbg 'WebSocket opened' if isdbg 'chan';
100    
101   # Increase inactivity timeout for connection a bit
102   $c->inactivity_timeout(300);
103  
104   # Incoming message
105   $c->on(
106                  message => sub {
107                          my ($c, $msg) = @_;
108                          dbg "websocket: $msg" if isdbg 'chan';
109                  },
110                  json => sub {
111                          my ($c, $msg) = @_;
112                          dbg "websocket: $msg" if isdbg 'chan';
113                  }
114   );
115  
116   # Closed
117   $c->on(finish => sub {
118     my ($c, $code, $reason) = @_;
119     $c->app->log->debug("WebSocket closed with status $code.");
120         dbg 'WebSocket closed with status $code' if isdbg 'chan';
121   });
122
123   $c->render;
124   
125 };
126
127 dbginit();
128 if (@ARGV) {
129         dbgadd(@ARGV);
130
131 dbgadd('chan');
132
133 dbg '***';
134 dbg "*** starting $0";
135 dbg '***';
136
137 our $dlog = SMGLog->new("day");
138 dbg "before next tick";
139 Mojo::IOLoop->next_tick(sub { loop() });        
140 dbg "before app start";
141 app->start;
142 dbg "after app start";
143
144 write_ld();
145 close $dataf if $dataf;
146
147 dbg '***';
148 dbg "*** ending $0";
149 dbg '***';
150
151 exit 0;
152
153 ##################################################################################
154         
155 sub loop
156 {
157
158         open $dataf, "+>>", $datafn or die "cannot open $datafn $!";
159         $dataf->autoflush(1);
160         
161         read_ld();
162         
163         dbg "last_min: " . scalar gmtime($ld->{last_min});
164         dbg "last_hour: " . scalar gmtime($ld->{last_hour});
165         
166         $did = Mojo::IOLoop->recurring(1 => sub {$dlog->flushall});
167         
168         do_reopen($devname);
169 }
170
171
172
173 sub on_read
174 {
175         my ($ser, $d) = @_;
176         $buf .= $d;
177         $d =~ s/([\%\x00-\x1f\x7f-\xff])/sprintf("%%%02X", ord($1))/eg; 
178         dbg "read added '$d' buf lth=" . length $buf if isdbg 'raw';
179         if ($state eq 'waitnl' && $buf =~ /[\cJ\cM]+/) {
180                 dbg "Got \\n" if isdbg 'state';
181                 Mojo::IOLoop->remove($tid) if $tid;
182                 undef $tid;
183                 undef $buf;
184                 $nlcount = 0;
185                 $ser->write("LPS 1 1\n");
186                 chgstate("waitloop");
187         } elsif ($state eq "waitloop") {
188                 if ($buf =~ /\x06/) {
189                         dbg "Got ACK 0x06" if isdbg 'state';
190                         chgstate('waitlooprec');
191                         undef $buf;
192                 }
193         } elsif ($state eq 'waitlooprec') {
194                 if (length $buf >= 99) {
195                         dbg "got loop record" if isdbg 'chan';
196                         chgstate('');
197                         process($buf);
198                         undef $buf;
199                 }
200         }
201 }
202
203 sub start_loop
204 {
205         $nlcount = 1;
206         dbg "start_loop writing $nlcount \\n" if isdbg 'state';
207         $ser->write("\n");
208         Mojo::IOLoop->remove($tid) if $tid;
209         undef $tid;
210         $tid = Mojo::IOLoop->recurring(0.6 => sub {
211                                                                            if (++$nlcount > 10) {
212                                                                                    dbg "\\n count > 10, closing connection" if isdbg 'chan';
213                                                                                    do_reopen($devname);
214                                                                                    return;
215                                                                            }
216                                                                            dbg "writing $nlcount \\n" if isdbg 'state'; 
217                                                                            $ser->write("\n");
218                                                                    });
219         chgstate("waitnl");
220 }
221
222 sub chgstate
223 {
224         dbg "state '$state' -> '$_[0]'" if isdbg 'state';
225         $state = $_[0];
226 }
227
228 sub do_reopen
229 {
230         my $name = shift;
231         dbg "do reopen on '$name' ending $ending";
232         unless ($ending) {
233                 $ser = do_open($name);
234                 start_loop();
235                 chgstate('');
236                 $nlcount = 0;
237                 Mojo::IOLoop->start unless Mojo::IOLoop->is_running;
238         }
239 }
240
241 sub do_open
242 {
243         my $name = shift;
244
245         $ser->close if $ser;
246         undef $ser;
247
248         my $ob = Serial->new($name, 19200) || die "$name $!\n";
249         dbg "streaming $name fileno(" . fileno($ob) . ")" if isdbg 'chan';
250         
251         my $ser = Mojo::IOLoop::Stream->new($ob);
252         $ser->on(error=>sub {dbg "serial $_[1]"; do_reopen($name) unless $ending});
253         $ser->on(close=>sub {dbg "serial closing"; do_reopen($name) unless $ending});
254         $ser->on(timeout=>sub {dbg "serial timeout";});
255         $ser->on(read=>sub {on_read(@_)});
256         $ser->start;
257
258         Mojo::IOLoop->remove($tid) if $tid;
259         undef $tid;
260         Mojo::IOLoop->remove($rid) if $rid;
261         undef $rid;
262         $rid = Mojo::IOLoop->recurring($poll_interval => sub {
263                                                                            start_loop() if !$state;
264                                                                    });
265         chgstate('');
266         $nlcount = 0;
267         
268         return $ser;
269 }
270
271 my @min;
272 my @hour;
273
274 sub process
275 {
276         my $blk = shift;
277         my $loo =  substr $blk,0,3;
278         unless ( $loo eq 'LOO') {
279                 dbg "Block invalid loo -> $loo" if isdbg 'chan'; return;
280         }
281
282         my $tmp;
283         my $rain;
284         my %h;
285
286         my $crc_calc = CRC_CCITT($blk);
287
288         if ($crc_calc==0) {
289
290                 # Common ones
291                 $tmp = unpack("s", substr $blk,7,2) / 1000;
292                 $h{Pressure} = nearest(1, in2mb($tmp));
293
294                 $tmp = unpack("s", substr $blk,9,2) / 10;
295                 $h{Temp_In} = nearest(0.1, f2c($tmp));
296
297                 $tmp  = unpack("s", substr $blk,12,2) / 10;
298                 $h{Temp_Out}  = nearest(0.1, f2c($tmp));
299
300                 $tmp = unpack("C", substr $blk,14,1);
301                 $h{Wind} = nearest(0.1, mph2mps($tmp));
302                 $h{Dir}     = unpack("s", substr $blk,16,2)+0;
303
304                 my $wind = {w => $h{Wind}, d => $h{Dir}};
305                 push @{$ld->{wind_min}}, $wind;
306
307                 $h{Humidity_Out} = unpack("C", substr $blk,33,1)+0;
308                 $h{Humidity_In}  = unpack("C", substr $blk,11,1)+0;
309
310                 $tmp = unpack("C", substr $blk,43,1)+0;
311                 $h{UV} = $tmp unless $tmp >= 255;
312                 $tmp = unpack("s", substr $blk,44,2)+0; # watt/m**2
313                 $h{Solar} = $tmp unless $tmp >= 32767;
314
315                 #       $h{Rain_Rate}  = nearest(0.1,unpack("s", substr $blk,41,2) * $rain_mult);
316                 $rain = $h{Rain_Day}   = nearest(0.1, unpack("s", substr $blk,50,2) * $rain_mult);
317                 my $delta_rain = $h{Rain} = nearest(0.1, ($rain >= $ld->{last_rain} ? $rain - $ld->{last_rain} : $rain)) if $loop_count;
318                 $ld->{last_rain} = $rain;
319
320                 # what sort of packet is it?
321                 my $sort =  unpack("C", substr $blk,4,1);
322                 if ($sort) {
323
324                         # Newer LOOP2 packet
325                         $tmp = unpack("C", substr $blk,18,2);
326                         #               $h{Wind_Avg_10} = nearest(0.1,mph2mps($tmp/10));
327                         $tmp = unpack("C", substr $blk,20,2);
328                         #               $h{Wind_Avg_2} = nearest(0.1,mph2mps($tmp/10));
329                         $tmp = unpack("C", substr $blk,22,2);
330                         #               $h{Wind_Gust_10} = nearest(0.1,mph2mps($tmp/10));
331
332                         #               $h{Dir_Avg_10} = unpack("C", substr $blk,24,2)+0;
333                         $tmp = unpack("C", substr $blk,30,2);
334                         $h{Dew_Point} = nearest(0.1, f2c($tmp));
335
336                 } else {
337
338                         # Older LOOP packet
339                         $tmp = unpack("C", substr $blk,15,1);
340                         #               $h{Wind_Avg_10} = nearest(0.1,mph2mps($tmp));
341                         $h{Dew_Point}  = nearest(0.1, dew_point($h{Temp_Out}, $h{Humidity_Out}));
342                         $h{Rain_Month}  = nearest(0.1, unpack("s", substr $blk,52,2) * $rain_mult);
343                         $h{Rain_Year}  = nearest(0.1, unpack("s", substr $blk,54,2) * $rain_mult);
344                 }
345
346                 my $ts = time;
347                 my $s;
348                 if ($ts >= $ld->{last_hour} + 3600) {
349                         $h{Pressure_Trend}    = unpack("C", substr $blk,3,1);
350                         $h{Pressure_Trend_txt} = $bar_trend{$h{Pressure_Trend}};
351                         $h{Batt_TX_OK}  = (unpack("C", substr $blk,86,1)+0) ^ 1;
352                         $h{Batt_Console}  = nearest(0.01, unpack("s", substr $blk,87,2) * 0.005859375);
353                         $h{Forecast_Icon}  = unpack("C", substr $blk,89,1);
354                         $h{Forecast_Rule}  = unpack("C", substr $blk,90,1);
355                         $h{Sunrise}  = sprintf( "%04d", unpack("S", substr $blk,91,2) );
356                         $h{Sunrise}  =~ s/(\d{2})(\d{2})/$1:$2/;
357                         $h{Sunset}   = sprintf( "%04d", unpack("S", substr $blk,93,2) );
358                         $h{Sunset}  =~ s/(\d{2})(\d{2})/$1:$2/;
359
360                         if ($loop_count) {      # i.e not the first
361                                 my $a = wind_average(scalar @{$ld->{wind_hour}} ? @{$ld->{wind_hour}} : {w => $h{Wind}, d => $h{Dir}});
362
363                                 $h{Wind_1h} = nearest(0.1, $a->{w});
364                                 $h{Dir_1h} = nearest(0.1, $a->{d});
365
366                                 $a = wind_average(@{$ld->{wind_min}});
367                                 $h{Wind_1m} = nearest(0.1, $a->{w});
368                                 $h{Dir_1m} = nearest(1, $a->{d});
369
370                                 ($h{Rain_1m}, $h{Rain_1h}, $h{Rain_24h}) = calc_rain($rain);
371                         }
372                         $ld->{last_rain_min} = $ld->{last_rain_hour} = $rain;
373
374                         $s = genstr($ts, 'h', \%h);
375                         
376                         $ld->{last_hour} = int($ts/3600)*3600;
377                         $ld->{last_min} = int($ts/60)*60;
378                         @{$ld->{wind_hour}} = ();
379                         @{$ld->{wind_min}} = ();
380
381                         write_ld();
382                         
383                 } elsif ($ts >= $ld->{last_min} + 60) {
384                         my $a = wind_average(@{$ld->{wind_min}});
385                         my %save;
386
387                         push @{$ld->{wind_hour}}, $a;
388
389                         if ($loop_count) {      # i.e not the first
390                                 my $rm;
391                                 
392                                 $h{Wind_1m} = nearest(0.1, $a->{w});
393                                 $h{Dir_1m} = nearest(1, $a->{d});
394                                 ($h{Rain_1m}, $h{Rain_1h}, $h{Rain_24h}) = calc_rain($rain);
395                         }
396                         $ld->{last_rain_min} = $rain;
397
398                         $s = genstr($ts, 'm', \%h);
399                         
400                         $ld->{last_min} = int($ts/60)*60;
401                         @{$ld->{wind_min}} = ();
402                         
403                         write_ld();
404
405                 } else {
406                         my $o = gen_hash_diff($ld->{last_h}, \%h);
407                         if ($o) {
408                                 $s = genstr($ts, 'r', $o);
409                         }
410                         else {
411                                 dbg "loop rec not changed" if isdbg 'chan';
412                         }
413                 }
414                 output_str($s) if $s;
415                 $ld->{last_h} = \%h;
416                 ++$loop_count;
417         } else {
418                 dbg "CRC check failed for LOOP data!";
419         }
420         return;
421 }
422
423 sub genstr
424 {
425         my $ts = shift;
426         my $let = shift;
427         my $h = shift;
428         
429         my $j =  $json->encode($h);
430         my ($sec,$min,$hr) = (gmtime $ts)[0,1,2];
431         my $tm = sprintf "%02d:%02d:%02d", $hr, $min, $sec;
432         
433         return qq|{"tm":"$tm","t":$ts,"$let":$j}|;
434 }
435
436 sub output_str
437 {
438         my $s = shift;
439         dbg $s;
440 #       say $s;
441         $dlog->writenow($s);
442 }
443
444 sub gen_hash_diff
445 {
446         my $last = shift;
447         my $now = shift;
448         my %o;
449         my $count;
450
451         while (my ($k, $v) = each %$now) {
452                 if ($last->{$k} ne $now->{$k}) {
453                         $o{$k} = $v;
454                         ++$count;
455                 }
456         }
457         return $count ? \%o : undef;
458 }
459
460 sub dew_point
461 {
462         my $temp = shift @_;
463         my $rh   = shift @_;
464
465         #  Using the simplified approximation for dew point
466         #  Accurate to 1 degree C for humidities > 50 %
467         #  http://en.wikipedia.org/wiki/Dew_point
468
469         my $dewpoint = $temp - ((100 - $rh) / 5);
470
471         # this is the more complete one (which doesn't work)
472         #my $a = 6.1121;
473         #my $b = 18.678;
474         #my $c = 257.14;
475         #my $ytrh = log(($rh/100) + ($b * $temp) / ($c + $temp));
476         #my $dewpoint = ($c * $ytrh) / ($b - $ytrh); 
477
478         return $dewpoint;
479 }
480
481 sub CRC_CCITT
482 {
483     # Expects packed data...
484     my $data_str = shift @_;
485
486         my $crc = 0;
487         my @lst = split //, $data_str;
488         foreach my $data (@lst) {
489                 my $data = unpack("c",$data);
490
491                 my $crc_prev = $crc;
492                 my $index = $crc >> 8 ^ $data;
493                 my $lhs = $crc_table[$index];
494                 #print "lhs=$lhs, crc=$crc\n";
495                 my $rhs = ($crc << 8) & 0xFFFF;
496                 $crc = $lhs ^ $rhs;
497
498
499         }
500
501         return $crc;
502 }
503
504 sub f2c
505 {
506         return ($_[0] - 32) * 5/9;
507 }
508
509 sub mph2mps
510 {
511         return $_[0] * 0.44704;
512 }
513
514 sub in2mb
515 {
516         return $_[0] * 33.8637526;
517 }
518
519 sub wind_average
520 {
521         my ($sindir, $cosdir, $wind);
522         my $count;
523         
524         foreach my $r (@_) {
525                 $wind += $r->{w};
526                 $sindir += sin(d2r($r->{d})) * $r->{w};
527                 $cosdir += cos(d2r($r->{d})) * $r->{w};
528                 ++$count;
529         }
530
531         my $avhdg = r2d(atan2($sindir, $cosdir));
532         $avhdg += 360 if $avhdg < 0; 
533         return {w => nearest(0.1,$wind / $count), d => nearest(0.1,$avhdg)};
534 }
535
536 # radians to degrees
537 sub r2d
538 {
539     my $n = shift;
540     return ($n / pi) * 180;
541 }
542
543 # degrees to radians
544 sub d2r 
545 {
546     my $n = shift;
547     return ($n / 180) * pi;
548 }
549
550 sub calc_rain
551 {
552         my $rain = shift;
553         
554         $ld->{rain24} ||= [];
555         
556         my $Rain_1h = nearest(0.1, $rain >= $ld->{last_rain_hour} ? $rain - $ld->{last_rain_hour} : $rain); # this is the rate for this hour, so far
557         my $rm = $rain >= $ld->{last_rain_min} ? $rain - $ld->{last_rain_min} : $rain;
558         my $Rain_1m = nearest(0.1, $rm);
559         push @{$ld->{rain24}}, $Rain_1m;
560         $ld->{rain_24} += $rm;
561         while (@{$ld->{rain24}} > 24*60) {
562                 $ld->{rain_24} -= shift @{$ld->{rain24}};
563         }
564         my $Rain_24h = nearest(0.1, $ld->{rain_24});
565         return ($Rain_1m, $Rain_1h, $Rain_24h);
566 }
567
568 sub read_ld
569 {
570         return unless $dataf;
571
572         seek $dataf, 0, 0;
573         my $s = <$dataf>;
574         chomp $s;
575         dbg "read loop data: $s" if isdbg 'json';
576         $ld = $json->decode($s) if length $s;
577         
578         # sort out rain stats
579         my $c;
580         if (($c = @{$ld->{rain24}}) < 24*60) {
581                 my $diff = 24*60 - $c;
582                 unshift @{$ld->{rain24}}, 0 for 0 .. $diff;  
583         }
584         my $rain;
585         $rain += $_ for @{$ld->{rain24}};
586         $ld->{rain_24} = nearest(0.1, $rain);
587         delete $ld->{hour};
588         delete $ld->{min};
589 }
590
591 sub write_ld
592 {
593         return unless $dataf;
594         
595         seek $dataf, 0, 0;
596         truncate $dataf, 0;
597         $ld->{ts} = time;
598         my $s = $json->encode($ld);
599         dbg "write loop data: $s" if isdbg 'json';
600         print $dataf "$s\n";
601 }
602
603
604 __DATA__
605  
606 @@ index.html.ep
607 <!DOCTYPE html>
608 <html>
609   <head><title>DWeather</title></head>
610   <body>
611     <script>
612       var ws;
613       if ("WebSocket" in window) {
614         ws = new WebSocket('<%= url_for('index')->to_abs %>');
615                 //ws = new WebSocket();
616       }
617       if(typeof(ws) !== 'undefined') {
618         ws.onmessage = function (event) {
619           document.body.innerHTML += JSON.parse(event.data).test;
620         };
621         ws.onopen = function (event) {
622           ws.send(JSON.stringify({weather: 'WebSocket support works! ♥'}));
623         };
624       }
625       else {
626         document.body.innerHTML += 'Browser does not support WebSockets.';
627       }
628
629       var ws = new WebSocket('<%= url_for('weather')->to_abs %>');
630  
631       // Incoming messages
632       ws.onmessage = function(event) {
633         document.body.innerHTML += event.data + '<br/>';
634       };
635  
636     </script>
637         <h1>DWeather</h1>
638
639   </body>
640 </html>