util: create new abstraction for compression engines
Currently, util.py has "compressors" and "decompressors" dicts
mapping compression algorithms to callables returning objects that
perform well-defined operations. In addition, revlog.py has code
for calling into a compressor or decompressor explicitly. And, there
is code in the wire protocol for performing zlib compression.
The 3rd party lz4revlog extension has demonstrated the utility of
supporting alternative compression formats for revlog storage. But
it stops short of supporting lz4 for bundles and the wire protocol.
There are also plans to support zstd as a general compression
replacement.
So, there appears to be a market for a unified API for registering
compression engines. This commit starts the process of establishing
one.
This commit establishes a base class/interface for defining
compression engines and how they will be used. A collection class
to hold references to registered compression engines has also been
introduced.
The built-in zlib, bz2, truncated bz2, and no-op compression engines
are registered with a singleton instance of the collection class.
The compression engine API will change once consumers are ported
to the new API and some common patterns can be simplified at the
engine API level. So don't get too attached to the API...
#require serve
Test chains of near empty directories, terminating 3 different ways:
- a1: file at level 4 (deepest)
- b1: two dirs at level 3
- d1: file at level 2
Set up the repo
$ hg init test
$ cd test
$ mkdir -p a1/a2/a3/a4
$ mkdir -p b1/b2/b3/b4
$ mkdir -p b1/b2/b3/c4
$ mkdir -p d1/d2/d3/d4
$ echo foo > a1/a2/a3/a4/foo
$ echo foo > b1/b2/b3/b4/foo
$ echo foo > b1/b2/b3/c4/foo
$ echo foo > d1/d2/d3/d4/foo
$ echo foo > d1/d2/foo
$ hg ci -Ama
adding a1/a2/a3/a4/foo
adding b1/b2/b3/b4/foo
adding b1/b2/b3/c4/foo
adding d1/d2/d3/d4/foo
adding d1/d2/foo
$ hg serve -n test -p $HGPORT -d --pid-file=hg.pid -E errors.log
$ cat hg.pid >> $DAEMON_PIDS
manifest with descending (paper)
$ get-with-headers.py 127.0.0.1:$HGPORT 'file'
200 Script output follows
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
<head>
<link rel="icon" href="/static/hgicon.png" type="image/png" />
<meta name="robots" content="index, nofollow" />
<link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
<script type="text/javascript" src="/static/mercurial.js"></script>
<title>test: c9f45f7a1659 /</title>
</head>
<body>
<div class="container">
<div class="menu">
<div class="logo">
<a href="https://mercurial-scm.org/">
<img src="/static/hglogo.png" alt="mercurial" /></a>
</div>
<ul>
<li><a href="/shortlog/tip">log</a></li>
<li><a href="/graph/tip">graph</a></li>
<li><a href="/tags">tags</a></li>
<li><a href="/bookmarks">bookmarks</a></li>
<li><a href="/branches">branches</a></li>
</ul>
<ul>
<li><a href="/rev/tip">changeset</a></li>
<li class="active">browse</li>
</ul>
<ul>
</ul>
<ul>
<li><a href="/help">help</a></li>
</ul>
</div>
<div class="main">
<h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
<h3>
directory / @ 0:<a href="/rev/c9f45f7a1659">c9f45f7a1659</a>
<span class="tag">tip</span>
</h3>
<form class="search" action="/log">
<p><input name="rev" id="search1" type="text" size="30" /></p>
<div id="hint">Find changesets by keywords (author, files, the commit message), revision
number or hash, or <a href="/help/revsets">revset expression</a>.</div>
</form>
<table class="bigtable">
<thead>
<tr>
<th class="name">name</th>
<th class="size">size</th>
<th class="permissions">permissions</th>
</tr>
</thead>
<tbody class="stripes2">
<tr class="fileline">
<td class="name"><a href="/file/tip/">[up]</a></td>
<td class="size"></td>
<td class="permissions">drwxr-xr-x</td>
</tr>
<tr class="fileline">
<td class="name">
<a href="/file/tip/a1">
<img src="/static/coal-folder.png" alt="dir."/> a1/
</a>
<a href="/file/tip/a1/a2/a3/a4">
a2/a3/a4
</a>
</td>
<td class="size"></td>
<td class="permissions">drwxr-xr-x</td>
</tr>
<tr class="fileline">
<td class="name">
<a href="/file/tip/b1">
<img src="/static/coal-folder.png" alt="dir."/> b1/
</a>
<a href="/file/tip/b1/b2/b3">
b2/b3
</a>
</td>
<td class="size"></td>
<td class="permissions">drwxr-xr-x</td>
</tr>
<tr class="fileline">
<td class="name">
<a href="/file/tip/d1">
<img src="/static/coal-folder.png" alt="dir."/> d1/
</a>
<a href="/file/tip/d1/d2">
d2
</a>
</td>
<td class="size"></td>
<td class="permissions">drwxr-xr-x</td>
</tr>
</tbody>
</table>
</div>
</div>
<script type="text/javascript">process_dates()</script>
</body>
</html>
manifest with descending (coal)
$ get-with-headers.py 127.0.0.1:$HGPORT 'file?style=coal'
200 Script output follows
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
<head>
<link rel="icon" href="/static/hgicon.png" type="image/png" />
<meta name="robots" content="index, nofollow" />
<link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
<link rel="stylesheet" href="/static/style-extra-coal.css" type="text/css" />
<script type="text/javascript" src="/static/mercurial.js"></script>
<title>test: c9f45f7a1659 /</title>
</head>
<body>
<div class="container">
<div class="menu">
<div class="logo">
<a href="https://mercurial-scm.org/">
<img src="/static/hglogo.png" alt="mercurial" /></a>
</div>
<ul>
<li><a href="/shortlog/tip?style=coal">log</a></li>
<li><a href="/graph/tip?style=coal">graph</a></li>
<li><a href="/tags?style=coal">tags</a></li>
<li><a href="/bookmarks?style=coal">bookmarks</a></li>
<li><a href="/branches?style=coal">branches</a></li>
</ul>
<ul>
<li><a href="/rev/tip?style=coal">changeset</a></li>
<li class="active">browse</li>
</ul>
<ul>
</ul>
<ul>
<li><a href="/help?style=coal">help</a></li>
</ul>
</div>
<div class="main">
<h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
<h3>
directory / @ 0:<a href="/rev/c9f45f7a1659?style=coal">c9f45f7a1659</a>
<span class="tag">tip</span>
</h3>
<form class="search" action="/log">
<input type="hidden" name="style" value="coal" />
<p><input name="rev" id="search1" type="text" size="30" /></p>
<div id="hint">Find changesets by keywords (author, files, the commit message), revision
number or hash, or <a href="/help/revsets">revset expression</a>.</div>
</form>
<table class="bigtable">
<thead>
<tr>
<th class="name">name</th>
<th class="size">size</th>
<th class="permissions">permissions</th>
</tr>
</thead>
<tbody class="stripes2">
<tr class="fileline">
<td class="name"><a href="/file/tip/?style=coal">[up]</a></td>
<td class="size"></td>
<td class="permissions">drwxr-xr-x</td>
</tr>
<tr class="fileline">
<td class="name">
<a href="/file/tip/a1?style=coal">
<img src="/static/coal-folder.png" alt="dir."/> a1/
</a>
<a href="/file/tip/a1/a2/a3/a4?style=coal">
a2/a3/a4
</a>
</td>
<td class="size"></td>
<td class="permissions">drwxr-xr-x</td>
</tr>
<tr class="fileline">
<td class="name">
<a href="/file/tip/b1?style=coal">
<img src="/static/coal-folder.png" alt="dir."/> b1/
</a>
<a href="/file/tip/b1/b2/b3?style=coal">
b2/b3
</a>
</td>
<td class="size"></td>
<td class="permissions">drwxr-xr-x</td>
</tr>
<tr class="fileline">
<td class="name">
<a href="/file/tip/d1?style=coal">
<img src="/static/coal-folder.png" alt="dir."/> d1/
</a>
<a href="/file/tip/d1/d2?style=coal">
d2
</a>
</td>
<td class="size"></td>
<td class="permissions">drwxr-xr-x</td>
</tr>
</tbody>
</table>
</div>
</div>
<script type="text/javascript">process_dates()</script>
</body>
</html>
manifest with descending (monoblue)
$ get-with-headers.py 127.0.0.1:$HGPORT 'file?style=monoblue'
200 Script output follows
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<link rel="icon" href="/static/hgicon.png" type="image/png" />
<meta name="robots" content="index, nofollow"/>
<link rel="stylesheet" href="/static/style-monoblue.css" type="text/css" />
<script type="text/javascript" src="/static/mercurial.js"></script>
<title>test: files</title>
<link rel="alternate" type="application/atom+xml" href="/atom-log" title="Atom feed for test"/>
<link rel="alternate" type="application/rss+xml" href="/rss-log" title="RSS feed for test"/>
</head>
<body>
<div id="container">
<div class="page-header">
<h1 class="breadcrumb"><a href="/">Mercurial</a> / files</h1>
<form action="/log">
<input type="hidden" name="style" value="monoblue" />
<dl class="search">
<dt><label>Search: </label></dt>
<dd><input type="text" name="rev" /></dd>
</dl>
</form>
<ul class="page-nav">
<li><a href="/summary?style=monoblue">summary</a></li>
<li><a href="/shortlog?style=monoblue">shortlog</a></li>
<li><a href="/changelog?style=monoblue">changelog</a></li>
<li><a href="/graph/tip?style=monoblue">graph</a></li>
<li><a href="/tags?style=monoblue">tags</a></li>
<li><a href="/bookmarks?style=monoblue">bookmarks</a></li>
<li><a href="/branches?style=monoblue">branches</a></li>
<li class="current">files</li>
<li><a href="/help?style=monoblue">help</a></li>
</ul>
</div>
<ul class="submenu">
<li><a href="/rev/tip?style=monoblue">changeset</a></li>
</ul>
<h2 class="no-link no-border">files</h2>
<p class="files">/ <span class="logtags"><span class="branchtag" title="default">default</span> <span class="tagtag" title="tip">tip</span> </span></p>
<table>
<tr class="parity0">
<td>drwxr-xr-x</td>
<td></td>
<td></td>
<td><a href="/file/tip/?style=monoblue">[up]</a></td>
<td class="link"> </td>
</tr>
<tr class="parity1">
<td>drwxr-xr-x</td>
<td></td>
<td></td>
<td>
<a href="/file/tip/a1?style=monoblue">a1</a>
<a href="/file/tip/a1/a2/a3/a4?style=monoblue">a2/a3/a4</a>
</td>
<td><a href="/file/tip/a1?style=monoblue">files</a></td>
</tr>
<tr class="parity0">
<td>drwxr-xr-x</td>
<td></td>
<td></td>
<td>
<a href="/file/tip/b1?style=monoblue">b1</a>
<a href="/file/tip/b1/b2/b3?style=monoblue">b2/b3</a>
</td>
<td><a href="/file/tip/b1?style=monoblue">files</a></td>
</tr>
<tr class="parity1">
<td>drwxr-xr-x</td>
<td></td>
<td></td>
<td>
<a href="/file/tip/d1?style=monoblue">d1</a>
<a href="/file/tip/d1/d2?style=monoblue">d2</a>
</td>
<td><a href="/file/tip/d1?style=monoblue">files</a></td>
</tr>
</table>
<script type="text/javascript">process_dates()</script>
<div class="page-footer">
<p>Mercurial Repository: test</p>
<ul class="rss-logo">
<li><a href="/rss-log">RSS</a></li>
<li><a href="/atom-log">Atom</a></li>
</ul>
</div>
<div id="powered-by">
<p><a href="https://mercurial-scm.org/" title="Mercurial"><img src="/static/hglogo.png" width=75 height=90 border=0 alt="mercurial" /></a></p>
</div>
</div>
</body>
</html>
manifest with descending (gitweb)
$ get-with-headers.py 127.0.0.1:$HGPORT 'file?style=gitweb'
200 Script output follows
<?xml version="1.0" encoding="ascii"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US" lang="en-US">
<head>
<link rel="icon" href="/static/hgicon.png" type="image/png" />
<meta name="robots" content="index, nofollow"/>
<link rel="stylesheet" href="/static/style-gitweb.css" type="text/css" />
<script type="text/javascript" src="/static/mercurial.js"></script>
<title>test: files</title>
<link rel="alternate" type="application/atom+xml"
href="/atom-log" title="Atom feed for test"/>
<link rel="alternate" type="application/rss+xml"
href="/rss-log" title="RSS feed for test"/>
</head>
<body>
<div class="page_header">
<a href="https://mercurial-scm.org/" title="Mercurial" style="float: right;">Mercurial</a>
<a href="/">Mercurial</a> / files
</div>
<div class="page_nav">
<a href="/summary?style=gitweb">summary</a> |
<a href="/shortlog?style=gitweb">shortlog</a> |
<a href="/log?style=gitweb">changelog</a> |
<a href="/graph?style=gitweb">graph</a> |
<a href="/tags?style=gitweb">tags</a> |
<a href="/bookmarks?style=gitweb">bookmarks</a> |
<a href="/branches?style=gitweb">branches</a> |
files |
<a href="/rev/tip?style=gitweb">changeset</a> |
<a href="/help?style=gitweb">help</a>
<br/>
</div>
<div class="title">/ <span class="logtags"><span class="branchtag" title="default">default</span> <span class="tagtag" title="tip">tip</span> </span></div>
<table cellspacing="0">
<tr class="parity0">
<td style="font-family:monospace">drwxr-xr-x</td>
<td style="font-family:monospace"></td>
<td style="font-family:monospace"></td>
<td><a href="/file/tip/?style=gitweb">[up]</a></td>
<td class="link"> </td>
</tr>
<tr class="parity1">
<td style="font-family:monospace">drwxr-xr-x</td>
<td style="font-family:monospace"></td>
<td style="font-family:monospace"></td>
<td>
<a href="/file/tip/a1?style=gitweb">a1</a>
<a href="/file/tip/a1/a2/a3/a4?style=gitweb">a2/a3/a4</a>
</td>
<td class="link">
<a href="/file/tip/a1?style=gitweb">files</a>
</td>
</tr>
<tr class="parity0">
<td style="font-family:monospace">drwxr-xr-x</td>
<td style="font-family:monospace"></td>
<td style="font-family:monospace"></td>
<td>
<a href="/file/tip/b1?style=gitweb">b1</a>
<a href="/file/tip/b1/b2/b3?style=gitweb">b2/b3</a>
</td>
<td class="link">
<a href="/file/tip/b1?style=gitweb">files</a>
</td>
</tr>
<tr class="parity1">
<td style="font-family:monospace">drwxr-xr-x</td>
<td style="font-family:monospace"></td>
<td style="font-family:monospace"></td>
<td>
<a href="/file/tip/d1?style=gitweb">d1</a>
<a href="/file/tip/d1/d2?style=gitweb">d2</a>
</td>
<td class="link">
<a href="/file/tip/d1?style=gitweb">files</a>
</td>
</tr>
</table>
<script type="text/javascript">process_dates()</script>
<div class="page_footer">
<div class="page_footer_text">test</div>
<div class="rss_logo">
<a href="/rss-log">RSS</a>
<a href="/atom-log">Atom</a>
</div>
<br />
</div>
</body>
</html>
manifest with descending (spartan)
$ get-with-headers.py 127.0.0.1:$HGPORT 'file?style=spartan'
200 Script output follows
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<link rel="icon" href="/static/hgicon.png" type="image/png">
<meta name="robots" content="index, nofollow" />
<link rel="stylesheet" href="/static/style.css" type="text/css" />
<script type="text/javascript" src="/static/mercurial.js"></script>
<title>test: files for changeset c9f45f7a1659</title>
</head>
<body>
<div class="buttons">
<a href="/log/tip?style=spartan">changelog</a>
<a href="/shortlog/tip?style=spartan">shortlog</a>
<a href="/graph/tip?style=spartan">graph</a>
<a href="/tags?style=spartan">tags</a>
<a href="/branches?style=spartan">branches</a>
<a href="/rev/tip?style=spartan">changeset</a>
<a href="/help?style=spartan">help</a>
</div>
<h2><a href="/">Mercurial</a> / files for changeset <a href="/rev/c9f45f7a1659">c9f45f7a1659</a>: /</h2>
<table cellpadding="0" cellspacing="0">
<tr class="parity0">
<td><tt>drwxr-xr-x</tt>
<td>
<td>
<td><a href="/file/tip/?style=spartan">[up]</a>
</tr>
<tr class="parity1">
<td><tt>drwxr-xr-x</tt>
<td>
<td>
<td>
<a href="/file/tip/a1?style=spartan">a1/</a>
<a href="/file/tip/a1/a2/a3/a4?style=spartan">
a2/a3/a4
</a>
<tr class="parity0">
<td><tt>drwxr-xr-x</tt>
<td>
<td>
<td>
<a href="/file/tip/b1?style=spartan">b1/</a>
<a href="/file/tip/b1/b2/b3?style=spartan">
b2/b3
</a>
<tr class="parity1">
<td><tt>drwxr-xr-x</tt>
<td>
<td>
<td>
<a href="/file/tip/d1?style=spartan">d1/</a>
<a href="/file/tip/d1/d2?style=spartan">
d2
</a>
</table>
<script type="text/javascript">process_dates()</script>
<div class="logo">
<a href="https://mercurial-scm.org/">
<img src="/static/hglogo.png" width=75 height=90 border=0 alt="mercurial"></a>
</div>
</body>
</html>
$ cat errors.log
$ cd ..