Python Paste

Python Paste brings consistency to Python web development and web application installation, providing tools for both developers and system administrators.

a Python Web Framework built on top of WSGI?

by Ian Bicking

http://pythonpaste.org/

context/framing

URI parsing/dispatching http://pythonpaste.org/url-parsing-with-wsgi.html


Apr'2006

Python Paste coming from Python On Mac

  • Paste Deploy: got good results from running 'sudo easy_install Paste Deploy'

  • Paste Script: 'sudo easy_install Paste Script'

  • Once, installed, '/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste-0.5-py2.4.egg' is a directory.

  • Going into 'paste' subdirectory and running 'python httpserver.py' launches a Web Server on port 8888.

  • actually using it with Rhubarb Tart

Oct'2006

Dropping Rhubarb Tart, just trying Selector with Python Paste.

Since Python Paste has gone v1, I'll upgrade. Since it uses Easy Install, that's easy::

easy_install --upgrade Paste Searching for Paste Reading http://www.python.org/pypi/Paste/ Reading http://pythonpaste.org Best match: Paste 1.0 Downloading http://cheeseshop.python.org/packages/2.4/P/Paste/Paste-1.0-py2.4.egg#md5=33775bbab4aa873ed691323d99893ecb Processing Paste-1.0-py2.4.egg creating /Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste-1.0-py2.4.egg Extracting Paste-1.0-py2.4.egg to /Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages Removing Paste 0.5 from easy-install.pth file Adding Paste 1.0 to easy-install.pth file Installed /Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste-1.0-py2.4.egg Processing dependencies for Paste

You create a new app with 'paster create' (you can have different Templates). There are 2 sample apps: a To-Do List that uses a Data Base back-end, and [a](http://svn.pythonpaste.org/Paste/apps/File Browser/trunk/) File Browser (which uses WareWeb and a number of other libraries).

I tried a 'create' without naming a template at all::

~/Documents/flux billseitz$ paster create flux Selected and implied templates: Paste Script#basic_package A basic setuptools-enabled package Variables: package: flux project: flux Creating template basic_package Enter version (Version (like 0.1)) ['']: 0.1 (snip) Enter zip_safe (True/False: if the package can be distributed as a .zip file) [False]: Creating directory ./flux Recursing into +package+ Creating ./flux/flux/ Copying init.py to ./flux/flux/init.py Copying setup.cfg to ./flux/setup.cfg Copying setup.py_tmpl to ./flux/setup.py Running /Library/Frameworks/Python.framework/Versions/2.4/Resources/Python.app/Contents/MacOS/Python setup.py egg_info

An app includes directories: (app-name), docs, and tests, plus a setup.py file. I think it also includes a setup.cfg file and an '(app-name).egg-info' directory.

Here's some explanation of writing Hello World, but it doesn't tie into the app just created. Would you put this code into 'init.py'?

  • so I tried putting the code there, then went into that directory and ran 'python init.py' and then pointed browser at http://localhost:8080/ and it worked.

Things seemed odd, so I tried again specifying 'basic_template'::

~/Documents/flux billseitz$ paster create flux template=basic_package Selected and implied templates: Paste Script#basic_package A basic setuptools-enabled package Variables: package: flux project: flux template: basic_package Creating template basic_package Enter version (Version (like 0.1)) ['']: 0.1 (snip) Enter zip_safe (True/False: if the package can be distributed as a .zip file) [False]: Creating directory ./flux Recursing into +package+ Creating ./flux/flux/ Copying init.py to ./flux/flux/init.py Copying setup.cfg to ./flux/setup.cfg Copying setup.py_tmpl to ./flux/setup.py Running /Library/Frameworks/Python.framework/Versions/2.4/Resources/Python.app/Contents/MacOS/Python setup.py egg_info

This didn't seem to make much of a difference. Neither approach gives you a 'docs' subfolder with 'example_config.ini' or 'devel_config.ini' files (the latter seems to be where you do URI-mapping a-la Selector).

  • this page notes it's creation, but that's from the file-browser sample app which uses multiple non-basic templates, so it's not clear to me where this comes from. Posted question to list.

Ian Bicking says I believe the paste_deploy template creates an ini file - basic_template potentially applies to non-web Python packages.

So try that::

~/Documents/flux billseitz$ paster create flux template=paste_deploy Selected and implied templates: Paste Script#basic_package A basic setuptools-enabled package Variables: package: flux project: flux template: paste_deploy Creating template basic_package Enter version (Version (like 0.1)) ['']: 0.1 (snip) Enter zip_safe (True/False: if the package can be distributed as a .zip file) [False]: Creating directory ./flux Recursing into +package+ Creating ./flux/flux/ Copying init.py to ./flux/flux/init.py Copying setup.cfg to ./flux/setup.cfg Copying setup.py_tmpl to ./flux/setup.py Running /Library/Frameworks/Python.framework/Versions/2.4/Resources/Python.app/Contents/MacOS/Python setup.py egg_info

That didn't do it either.

Jan20'2007 - upgrade all the packages (hadn't done that before), tried again. Still no success.

Even try using 'template="paste_deploy"' but that doesn't work either.

Maybe I'll just create the docs directory/files by hand, or check out the ones that are in the sample folder and copy them...::

find . -name devel_conf* ./Paste Deploy-0.5-py2.4.egg/paste/deploy/paster_templates/paste_deploy/docs/devel_config.ini_tmpl ./Paste Deploy-1.1-py2.4.egg/paste/deploy/paster_templates/paste_deploy/docs/devel_config.ini_tmpl ./Rhubarb Tart-0.6dev_r5247-py2.4.egg/rhubarbtart/paste_templates/rhubarbtart/docs/devel_config.ini_tmpl

That worked, though filename ends in *.ini_templ - but I just rip off the ending bit.

Try launching::

~/Documents/flux/flux billseitz$ paster serve docs/devel_config.ini Traceback (most recent call last): File "/Library/Frameworks/Python.framework/Versions/Current/bin/paster", line 5, in ? pkg_resources.run_script('Paste Script==0.5.2dev-r5241', 'paster') File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 407, in run_script self.require(requires)[0].run_script(script_name, ns) (***** snip many lines******) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 483, in resolve raise [Distribution Not Found] # XXX put more info here pkg_resources.Distribution Not Found: WSGIUtils

I see the wrong version of paster is running.

Go remove all the old directories in site_packages, try again::

paster serve docs/devel_config.ini Traceback (most recent call last): File "/Library/Frameworks/Python.framework/Versions/Current/bin/paster", line 4, in ? import pkg_resources File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 2441, in ? for dist in working_set.resolve( File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 483, in resolve raise [Distribution Not Found] # XXX put more info here pkg_resources.Distribution Not Found: Paste Script==0.5.2dev-r5241

Ugh, I suspect I should have deleted via Setup Tools rather than doing it directly. Or maybe it's that paster hasn't been updated::

cd /Library/Frameworks/Python.framework/Versions/Current/bin ls gives 289 20 May 2006 paster head paster #!/Library/Frameworks/Python.framework/Versions/2.4/Resources/Python.app/Contents/MacOS/Python

EASY-INSTALL-SCRIPT: 'Paste Script==0.5.2dev-r5241','paster'

requires = 'Paste Script==0.5.2dev-r5241' import pkg_resources pkg_resources.run_script('Paste Script==0.5.2dev-r5241', 'paster')

Yes, I used to have a directory 'Paste Script-0.5.2dev_r5241-py2.4.egg'

Do I need to upgrade that separately from Paste Script and Paste Deploy? I thought paster was part of Python Script...

So I'm going to edit that little paster file by hand...

Then try launching again::

paster serve docs/devel_config.ini Traceback (most recent call last): File "/Library/Frameworks/Python.framework/Versions/Current/bin/paster", line 5, in ? pkg_resources.run_script('Paste Script==1.1', 'paster') File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 407, in run_script self.require(requires)[0].run_script(script_name, ns) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 1084, in run_script execfile(script_filename, namespace, namespace) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/EGG-INFO/scripts/paster", line 18, in ? command.run() File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/paste/script/command.py", line 76, in run invoke(command, command_name, options, args[1:]) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/paste/script/command.py", line 115, in invoke exit_code = runner.run(args) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/paste/script/command.py", line 210, in run result = self.command() File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/paste/script/serve.py", line 192, in command relative_to=base, global_conf=vars) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/paste/script/serve.py", line 212, in loadserver relative_to=relative_to, **kw) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 199, in loadserver return loadobj(SERVER, uri, name=name, **kw) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 213, in loadobj global_conf=global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 237, in loadcontext global_conf=global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 267, in _loadconfig return loader.get_context(object_type, name, global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 393, in get_context section) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 414, in _context_from_use context = self.get_context( File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 345, in get_context global_conf=global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 237, in loadcontext global_conf=global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 274, in _loadegg return loader.get_context(object_type, name, global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 541, in get_context entry_point, protocol, ep_name = self.find_egg_entry_point( File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 568, in find_egg_entry_point possible.append((entry.load(), protocol, entry.name)) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 1829, in load if require: self.require(env, installer) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 1842, in require working_set.resolve(self.dist.requires(self.extras),env,installer)) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 483, in resolve raise [Distribution Not Found] # XXX put more info here pkg_resources.Distribution Not Found: WSGIUtils

Feb09

  • realize I have a WSGIUtils-0.7 zipped file on my desktop. Unzip, copy to /Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/WSGIUtils

  • tried launching again, same error

  • duh, WSGIUtils uses Easy Install, so I do that::

sudo easy_install wsgiutils Password: Searching for wsgiutils Reading http://www.python.org/pypi/wsgiutils/ Couldn't find index page for 'wsgiutils' (maybe misspelled?) Scanning index of all packages (this may take a while) Reading http://www.python.org/pypi/ Reading http://www.python.org/pypi/WSGIUtils/0.7 Reading http://www.owlfish.com/software/wsgiutils/index.html Best match: WSGIUtils 0.7 Downloading http://cheeseshop.python.org/packages/2.4/W/WSGIUtils/WSGIUtils-0.7-py2.4.egg#md5=828542ebebc0f72d006b931fdfeb216f Processing WSGIUtils-0.7-py2.4.egg Moving WSGIUtils-0.7-py2.4.egg to /Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages Adding WSGIUtils 0.7 to easy-install.pth file Installed /Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/WSGIUtils-0.7-py2.4.egg Processing dependencies for wsgiutils

  • try launch, get different error::

Traceback (most recent call last): File "/Library/Frameworks/Python.framework/Versions/Current/bin/paster", line 5, in ? pkg_resources.run_script('Paste Script==1.1', 'paster') File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 407, in run_script self.require(requires)[0].run_script(script_name, ns) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 1084, in run_script execfile(script_filename, namespace, namespace) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/EGG-INFO/scripts/paster", line 18, in ? command.run() File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/paste/script/command.py", line 76, in run invoke(command, command_name, options, args[1:]) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/paste/script/command.py", line 115, in invoke exit_code = runner.run(args) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/paste/script/command.py", line 210, in run result = self.command() File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/paste/script/serve.py", line 194, in command relative_to=base, global_conf=vars) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Script-1.1-py2.4.egg/paste/script/serve.py", line 215, in loadapp return loadapp( File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 193, in loadapp return loadobj(APP, uri, name=name, **kw) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 213, in loadobj global_conf=global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 237, in loadcontext global_conf=global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 267, in _loadconfig return loader.get_context(object_type, name, global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 384, in get_context global_additions=global_additions) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 454, in _filter_app_context context.next_context = self.get_context( File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 393, in get_context section) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 414, in _context_from_use context = self.get_context( File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 345, in get_context global_conf=global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 237, in loadcontext global_conf=global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 274, in _loadegg return loader.get_context(object_type, name, global_conf) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 541, in get_context entry_point, protocol, ep_name = self.find_egg_entry_point( File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 562, in find_egg_entry_point pkg_resources.require(self.spec) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 585, in require needed = self.resolve(parse_requirements(requirements)) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 464, in resolve requirements = list(requirements)[::-1] # set up the stack File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/setuptools-0.6a11-py2.4.egg/pkg_resources.py", line 2259, in parse_requirements raise Value Error("Missing distribution spec", line) Value Error: ('Missing distribution spec', '${project}')

I posted on the email list, and Ian responded: You probably have something like "use = egg:${project}" in a config file.

  • he was right, it was in that devel_config.ini file that I copied from elsewhere because I could get it auto-generated.

Feb18'2007

  • modified devel_config.ini to have use = egg:flux

  • now get::

    Traceback: (lots snipped) File "/Library/Frameworks/Python.framework/Versions/2.4/lib/python2.4/site-packages/Paste Deploy-1.1-py2.4.egg/paste/deploy/loadwsgi.py", line 573, in find_egg_entry_point raise Lookup Error( Lookup Error: Entry point 'main' not found in egg 'flux' (dir: /Users/billseitz/Documents/flux/flux; protocols: paste.app_factory, paste.composite_factory, paste.composit_factory; entry_points: )

  • do I edit entry_points.txt or something else?

Later play with Robaccia.


Edited: |

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