diff -r 5ff1fc726848 -r c6bca38c1cbf eggs/zc.buildout-1.5.2-py2.6.egg/zc/buildout/downloadcache.txt --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/eggs/zc.buildout-1.5.2-py2.6.egg/zc/buildout/downloadcache.txt Sat Jan 08 11:20:57 2011 +0530 @@ -0,0 +1,141 @@ +Using a download cache +====================== + +Normally, when distributions are installed, if any processing is +needed, they are downloaded from the internet to a temporary directory +and then installed from there. A download cache can be used to avoid +the download step. This can be useful to reduce network access and to +create source distributions of an entire buildout. + +The buildout download-cache option can be used to specify a directory +to be used as a download cache. + +In this example, we'll create a directory to hold the cache: + + >>> cache = tmpdir('cache') + +And set up a buildout that downloads some eggs: + + >>> write('buildout.cfg', + ... ''' + ... [buildout] + ... parts = eggs + ... download-cache = %(cache)s + ... find-links = %(link_server)s + ... + ... [eggs] + ... recipe = zc.recipe.egg + ... eggs = demo ==0.2 + ... ''' % globals()) + +We specified a link server that has some distributions available for +download: + + >>> print get(link_server), + + bigdemo-0.1-py2.4.egg
+ demo-0.1-py2.4.egg
+ demo-0.2-py2.4.egg
+ demo-0.3-py2.4.egg
+ demo-0.4c1-py2.4.egg
+ demoneeded-1.0.zip
+ demoneeded-1.1.zip
+ demoneeded-1.2c1.zip
+ extdemo-1.4.zip
+ index/
+ other-1.0-py2.4.egg
+ + + +We'll enable logging on the link server so we can see what's going on: + + >>> get(link_server+'enable_server_logging') + GET 200 /enable_server_logging + '' + +We also specified a download cache. + +If we run the buildout, we'll see the eggs installed from the link +server as usual: + + >>> print system(buildout), + GET 200 / + GET 200 /demo-0.2-py2.4.egg + GET 200 /demoneeded-1.2c1.zip + Installing eggs. + Getting distribution for 'demo==0.2'. + Got demo 0.2. + Getting distribution for 'demoneeded'. + Got demoneeded 1.2c1. + Generated script '/sample-buildout/bin/demo'. + +We'll also get the download cache populated. The buildout doesn't put +files in the cache directly. It creates an intermediate directory, +dist: + + + >>> ls(cache) + d dist + + >>> ls(cache, 'dist') + - demo-0.2-py2.4.egg + - demoneeded-1.2c1.zip + +If we remove the installed eggs from eggs directory and re-run the buildout: + + >>> import os + >>> for f in os.listdir('eggs'): + ... if f.startswith('demo'): + ... remove('eggs', f) + + >>> print system(buildout), + GET 200 / + Updating eggs. + Getting distribution for 'demo==0.2'. + Got demo 0.2. + Getting distribution for 'demoneeded'. + Got demoneeded 1.2c1. + +We see that the distributions aren't downloaded, because they're +downloaded from the cache. + +Installing solely from a download cache +--------------------------------------- + +A download cache can be used as the basis of application source +releases. In an application source release, we want to distribute an +application that can be built without making any network accesses. In +this case, we distribute a buildout with download cache and tell the +buildout to install from the download cache only, without making +network accesses. The buildout install-from-cache option can be used +to signal that packages should be installed only from the download +cache. + +Let's remove our installed eggs and run the buildout with the +install-from-cache option set to true: + + >>> for f in os.listdir('eggs'): + ... if f.startswith('demo'): + ... remove('eggs', f) + + >>> write('buildout.cfg', + ... ''' + ... [buildout] + ... parts = eggs + ... download-cache = %(cache)s + ... install-from-cache = true + ... find-links = %(link_server)s + ... + ... [eggs] + ... recipe = zc.recipe.egg + ... eggs = demo + ... ''' % globals()) + + >>> print system(buildout), + Uninstalling eggs. + Installing eggs. + Getting distribution for 'demo'. + Got demo 0.2. + Getting distribution for 'demoneeded'. + Got demoneeded 1.2c1. + Generated script '/sample-buildout/bin/demo'.