[tor-bugs] #11563 [DocTor]: Improve consensus-health page by reducing size of HTML

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#11563: Improve consensus-health page by reducing size of HTML
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 Reporter:  alphawolf         |          Owner:  atagar
     Type:  enhancement       |         Status:  new
 Priority:  normal            |      Milestone:
Component:  DocTor            |        Version:
 Keywords:  consensus-health  |  Actual Points:
Parent ID:                    |         Points:
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 '''Problem''':

   The consensus-health page @ https://consensus-health.torproject.org/ is
 currently ~ 5.4 MB uncompressed (231 KB over the wire, using gzip).  The
 large size of the uncompressed document makes browser rending take longer
 than it needs to, consumes excess RAM, and (probably) consumes excess CPU
 cycles on the server during compression, or excess bandwidth when served
 uncompressed.

 '''Specifics''':

  1. Redundant content:
    a. 25,862 instances of '<font color="blue">(.*?)</font>'
    a. 5,068 instances of '<font color="gray"><s>(.*?)</s></font>'
    a. 2,200 instances of '<font color="red">(.*?)</font>'
  1. Unnecessary elements:
    a. Headers in relay list use '<b>(.*?)<b/>' for bolding when changing
 the '<td>' to '<th>' would give the same presentation for less bytes,
 while being more semantically correct HTML.  (8,256 instances)
    a. Headers in relay list use '<br>' before each DirAuth name in order
 to provide spacing (8,256 instances)
  1. Unnecessary white space:
    a. 572,662 instances of <space><space>
    a. 97,899 instances of '\n' between (not inside) tags.

 '''Proposal''':

 Implement the following changes, which reduce the document size without
 affecting its presentation:

  1. Reduce redundant content:
    a. Remove '<font color="blue"></font>' for each individual flag, and
 set ' class="ic"' on the column instead.  Add appropriate CSS.
 '''Estimated savings: 600 KB'''
    a. Replace '<font color="gray"><s></s></font>' with '<span
 class="oic"><span>'.  Add appropriate CSS.  '''Estimated savings: 40 KB'''
    a. Replace '<font color="red"></font>' with '<span
 class="oiv"></span>'.  Add appropriate CSS.  '''Estimated savings:  This
 is actually a small net loss, but by changing <font> to <span> it will
 match the other changes and compress more efficiently.'''
  1. Remove unnecessary elements:
    a. Remove all '<b></b>' and '<br>' tags from the relay list headers.
 Set ' class="tbl-hdr"' on the <tr> and change '<td>' to '<th>'.  Add
 height and vertical alignment to CSS.  '''Estimated savings: 77 KB'''
  1. Remove unnecessary white space:
    a. <space><space>
      1. Replace each <space><space> with "\t".  '''Estimated savings: 570
 KB'''
      1. OR:  Remove all instances of <space><space> entirely.
 '''Estimated savings: 1.1 MB'''
      1. OR:  Replace the white space with a variable that can be enabled
 when white space is desired (for debuging purposes). ''' Estimated
 savings: 1.1 MB'''
    a. newline
      1. Remove all newlines after block/table-related elements. '''
 Estimated savings:  95 KB'''
      1. OR:  Replace newlines with variable that can be enabled for
 debugging purposes.  '''Estimated savings: 95 KB'''

 By implementing the above changes, the consensus-relay could be trimmed by
 up to 1.9 MB -- a full 1/3 of it's 5.4 MB bulk.  Since part 3 could be
 controversial, I'll put that in a separate patch (assuming it is wanted).
 I'm attaching a patch that implements parts 1 and 2.  It should trim the
 uncompressed document by around 700 KB.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/11563>
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