Add documentation

Change-Id: Ib236d2061f5f375f7314993db7e6fc38d0f8750b

doc/source/conf.py

@@ -0,0 +1,254 @@
+# -*- coding: utf-8 -*-
+#
+# tooz documentation build configuration file
+#
+# This file is execfile()d with the current directory set to its containing dir.
+#
+# Note that not all possible configuration values are present in this
+# autogenerated file.
+#
+# All configuration values have a default; values that are commented out
+# serve to show the default.
+
+import datetime
+import subprocess
+
+# If extensions (or modules to document with autodoc) are in another directory,
+# add these directories to sys.path here. If the directory is relative to the
+# documentation root, use os.path.abspath to make it absolute, like shown here.
+#sys.path.insert(0, os.path.abspath('.'))
+
+# -- General configuration -----------------------------------------------------
+
+# If your documentation needs a minimal Sphinx version, state it here.
+#needs_sphinx = '1.0'
+
+# Add any Sphinx extension module names here, as strings. They can be extensions
+# coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
+extensions = [
+    'sphinx.ext.autodoc',
+    'sphinx.ext.todo',
+    'sphinx.ext.graphviz',
+    'sphinx.ext.extlinks',
+]
+
+# Add any paths that contain templates here, relative to this directory.
+templates_path = ['_templates']
+
+# The suffix of source filenames.
+source_suffix = '.rst'
+
+# The encoding of source files.
+#source_encoding = 'utf-8-sig'
+
+# The master toctree document.
+master_doc = 'index'
+
+# General information about the project.
+project = u'tooz'
+copyright = u'%s, eNovance' % datetime.date.today().year
+
+# The version info for the project you're documenting, acts as replacement for
+# |version| and |release|, also used in various other places throughout the
+# built documents.
+#
+# The short X.Y version.
+version = subprocess.Popen(['sh', '-c', 'cd ../..; python setup.py --version'],
+                           stdout=subprocess.PIPE).stdout.read()
+version = version.strip()
+# The full version, including alpha/beta/rc tags.
+release = version
+
+# The language for content autogenerated by Sphinx. Refer to documentation
+# for a list of supported languages.
+#language = None
+
+# There are two options for replacing |today|: either, you set today to some
+# non-false value, then it is used:
+#today = ''
+# Else, today_fmt is used as the format for a strftime call.
+#today_fmt = '%B %d, %Y'
+
+# List of patterns, relative to source directory, that match files and
+# directories to ignore when looking for source files.
+exclude_patterns = []
+
+# The reST default role (used for this markup: `text`) to use for all documents.
+#default_role = None
+
+# If true, '()' will be appended to :func: etc. cross-reference text.
+#add_function_parentheses = True
+
+# If true, the current module name will be prepended to all description
+# unit titles (such as .. function::).
+#add_module_names = True
+
+# If true, sectionauthor and moduleauthor directives will be shown in the
+# output. They are ignored by default.
+#show_authors = False
+
+# The name of the Pygments (syntax highlighting) style to use.
+pygments_style = 'sphinx'
+
+# A list of ignored prefixes for module index sorting.
+#modindex_common_prefix = []
+
+
+# -- Options for HTML output ---------------------------------------------------
+
+# The theme to use for HTML and HTML Help pages.  See the documentation for
+# a list of builtin themes.
+html_theme = 'default'
+
+# Theme options are theme-specific and customize the look and feel of a theme
+# further.  For a list of options available for each theme, see the
+# documentation.
+#html_theme_options = {}
+
+# Add any paths that contain custom themes here, relative to this directory.
+#html_theme_path = []
+
+# The name for this set of Sphinx documents.  If None, it defaults to
+# "<project> v<release> documentation".
+#html_title = None
+
+# A shorter title for the navigation bar.  Default is the same as html_title.
+#html_short_title = None
+
+# The name of an image file (relative to this directory) to place at the top
+# of the sidebar.
+#html_logo = None
+
+# The name of an image file (within the static path) to use as favicon of the
+# docs.  This file should be a Windows icon file (.ico) being 16x16 or 32x32
+# pixels large.
+#html_favicon = None
+
+# Add any paths that contain custom static files (such as style sheets) here,
+# relative to this directory. They are copied after the builtin static files,
+# so a file named "default.css" will overwrite the builtin "default.css".
+html_static_path = ['_static']
+
+# If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
+# using the given strftime format.
+#html_last_updated_fmt = '%b %d, %Y'
+
+# If true, SmartyPants will be used to convert quotes and dashes to
+# typographically correct entities.
+#html_use_smartypants = True
+
+# Custom sidebar templates, maps document names to template names.
+#html_sidebars = {}
+
+# Additional templates that should be rendered to pages, maps page names to
+# template names.
+#html_additional_pages = {}
+
+# If false, no module index is generated.
+#html_domain_indices = True
+
+# If false, no index is generated.
+#html_use_index = True
+
+# If true, the index is split into individual pages for each letter.
+#html_split_index = False
+
+# If true, links to the reST sources are added to the pages.
+#html_show_sourcelink = True
+
+# If true, "Created using Sphinx" is shown in the HTML footer. Default is True.
+#html_show_sphinx = True
+
+# If true, "(C) Copyright ..." is shown in the HTML footer. Default is True.
+#html_show_copyright = True
+
+# If true, an OpenSearch description file will be output, and all pages will
+# contain a <link> tag referring to it.  The value of this option must be the
+# base URL from which the finished HTML is served.
+#html_use_opensearch = ''
+
+# This is the file name suffix for HTML files (e.g. ".xhtml").
+#html_file_suffix = None
+
+# Output file base name for HTML help builder.
+htmlhelp_basename = 'toozdoc'
+
+
+# -- Options for LaTeX output --------------------------------------------------
+
+latex_elements = {
+# The paper size ('letterpaper' or 'a4paper').
+#'papersize': 'letterpaper',
+
+# The font size ('10pt', '11pt' or '12pt').
+#'pointsize': '10pt',
+
+# Additional stuff for the LaTeX preamble.
+#'preamble': '',
+}
+
+# Grouping the document tree into LaTeX files. List of tuples
+# (source start file, target name, title, author, documentclass [howto/manual]).
+latex_documents = [
+  ('index', 'tooz.tex', u'tooz Documentation',
+   u'eNovance', 'manual'),
+]
+
+# The name of an image file (relative to this directory) to place at the top of
+# the title page.
+#latex_logo = None
+
+# For "manual" documents, if this is true, then toplevel headings are parts,
+# not chapters.
+#latex_use_parts = False
+
+# If true, show page references after internal links.
+#latex_show_pagerefs = False
+
+# If true, show URL addresses after external links.
+#latex_show_urls = False
+
+# Documents to append as an appendix to all manuals.
+#latex_appendices = []
+
+# If false, no module index is generated.
+#latex_domain_indices = True
+
+
+# -- Options for manual page output --------------------------------------------
+
+# One entry per manual page. List of tuples
+# (source start file, name, description, authors, manual section).
+# man_pages = [
+#     ('index', 'tooz', u'tooz Documentation',
+#      [u'eNovance'], 1)
+# ]
+
+# If true, show URL addresses after external links.
+#man_show_urls = False
+
+
+# -- Options for Texinfo output ------------------------------------------------
+
+# Grouping the document tree into Texinfo files. List of tuples
+# (source start file, target name, title, author,
+#  dir menu entry, description, category)
+texinfo_documents = [
+  ('index', 'tooz', u'tooz Documentation',
+   u'eNovance', 'tooz', 'One line description of project.',
+   'Miscellaneous'),
+]
+
+# Documents to append as an appendix to all manuals.
+#texinfo_appendices = []
+
+# If false, no module index is generated.
+#texinfo_domain_indices = True
+
+# How to display URL addresses: 'footnote', 'no', or 'inline'.
+#texinfo_show_urls = 'footnote'
+
+# extlinks = {
+# }
+
+autodoc_default_flags = ['members', 'special-members', 'show-inheritance']

doc/source/drivers.rst

@@ -0,0 +1,23 @@
+=======
+Drivers
+=======
+
+Tooz is provided with several drivers implementing the provided coordination
+API. While all drivers provides the same set of features with respect to the
+API, some of them have different properties:
+
+* `zookeeper`_ is the reference implementation and provides the most solid
+  features as it's possible to build a cluster of ZooKeeper that is
+  resilient towards network partitions for example.
+
+* `memcached`_ is a basic implementation and provides less resiliency, though
+  it's much simpler to setup. A lot of the features provided in tooz are
+  based on timeout (heartbeats, locks, etc) so are less resilient than other
+  backends.
+
+* `zake`_ is a driver using a fake implementation of ZooKeeper and can be
+  used to use Tooz in your unit tests suite for example.
+
+.. _zookeeper: http://zookeeper.apache.org/
+.. _memcached: http://memcached.org/
+.. _zake: https://pypi.python.org/pypi/zake

doc/source/index.rst

@@ -0,0 +1,22 @@
+=============================================================
+ tooz -- Distributed System Helper Library
+=============================================================
+
+The Tooz project aims at centralizing the most common distributed primitives
+like group membership protocol, lock service and leader election by providing
+a coordination API helping developers to build distributed applications.
+Contents:
+
+.. toctree::
+   :glob:
+
+   install
+   drivers
+   tutorial/index
+
+Indices and tables
+==================
+
+* :ref:`genindex`
+* :ref:`modindex`
+* :ref:`search`

doc/source/install.rst

@@ -0,0 +1,43 @@
+============
+Installation
+============
+
+Python Versions
+===============
+
+tooz is tested under Python 2.7 and 3.3.
+
+.. _install-basic:
+
+Basic Installation
+==================
+
+tooz should be installed into the same site-packages area where
+the application and extensions are installed (either a virtualenv or
+the global site-packages). You may need administrative privileges to
+do that.  The easiest way to install it is using pip_::
+
+  $ pip install tooz
+
+or::
+
+  $ sudo pip install tooz
+
+.. _pip: http://pypi.python.org/pypi/pip
+
+Download
+========
+
+tooz releases are hosted on PyPI and can be downloaded from:
+http://pypi.python.org/pypi/tooz
+
+Source Code
+===========
+
+The source is hosted on the OpenStack infrastructure: https://git.openstack.org/cgit/stackforge/tooz/
+
+Reporting Bugs
+==============
+
+Please report bugs through the launchpad project:
+https://launchpad.net/python-tooz

doc/source/tutorial/coordinator.rst

@@ -0,0 +1,42 @@
+=====================
+ Creating A Coordinator
+=====================
+
+The principal object provided by tooz is the *coordinator*. It allows you to
+use various features, such as group membership, leader election or
+distributed locking.
+
+The features provided by tooz coordinator are implemented using different
+drivers. When creating a coordinator, you need to specify which back-end
+driver you want it to use. Different drivers may provide different set of
+capabilities.
+
+If a driver does not support a feature, it will raise a
+:class:`~NotImplementedError` exception.
+
+This example program loads a basic coordinataor using the ZooKeeper based
+driver.
+
+.. literalinclude:: ../../../examples/coordinator.py
+   :language: python
+
+The second argument passed to the coordinator must be a unique identifier
+identifying the running program.
+
+After the coordinator is created, it can be used to use the various features
+provided.
+
+In order to keep the connection to the coordination server active, you must
+call regularly the :meth:`~tooz.coordination.CoordinationDriver.heartbeat`
+method. This will ensure that the coordinator is not considered dead by
+other program participating in the coordination.
+
+.. literalinclude:: ../../../examples/coordinator_heartbeat.py
+   :language: python
+
+We use a pretty simple mechanism in this example to send a heartbeat every
+once in a while, but depending on your application, you may want to send the
+heartbeat at different moment or intervals.
+
+Note that certain drivers, such as `memcached` are heavily based on timeout,
+so the interval used to run the heartbeat is important.

doc/source/tutorial/group_membership.rst

@@ -0,0 +1,41 @@
+=====================
+ Group Membership
+=====================
+
+Basic operations
+===================
+
+One of the feature provided by the coordinator is the ability to handle
+group membership. Once a group is created, any coordinator can join the
+group and become a member of it. Any coordinator can be notified when a
+members joins or leaves the group.
+
+.. literalinclude:: ../../../examples/group_membership.py
+   :language: python
+
+Note that all the operation are asynchronous. That means you cannot be sure
+that your group has been created or joined before you call the
+:meth:`tooz.coordination.CoordAsyncResult.get` method.
+
+You can also leave a group using the
+:meth:`tooz.coordination.CoordinationDriver.leave_group` method. The list of
+all available groups is retrievable via the
+:meth:`tooz.coordination.CoordinationDriver.get_groups` method.
+
+Watching Group Changes
+======================
+It's possible to watch and get notified when the member list of a group
+changes. That's useful to run callback functions whenever something happens
+in that group.
+
+
+.. literalinclude:: ../../../examples/group_membership_watch.py
+   :language: python
+
+Using :meth:`tooz.coordination.CoordinationDriver.watch_join_group` and
+:meth:`tooz.coordination.CoordinationDriver.watch_leave_group` your
+application can be notified each time a member join or leave a group. To
+stop watching an event, the two methods
+:meth:`tooz.coordination.CoordinationDriver.unwatch_join_group` and
+:meth:`tooz.coordination.CoordinationDriver.unwatch_leave_group` allow to
+unregister a particular callback.

doc/source/tutorial/index.rst

@@ -0,0 +1,13 @@
+=====================================
+ Using Tooz in Your Application
+=====================================
+
+This tutorial is a step-by-step walk-through demonstrating how to
+use tooz in your application.
+
+.. toctree::
+   :maxdepth: 2
+
+   coordinator
+   group_membership
+   leader_election

doc/source/tutorial/leader_election.rst

@@ -0,0 +1,25 @@
+=================
+ Leader Election
+=================
+
+Each group can elect its own leader. There can be only one leader at a time
+in a group. Only members that are running for the election can be elected.
+As soon as one of leader steps down or dies, a new member that was running
+for the election will be elected.
+
+.. literalinclude:: ../../../examples/leader_election.py
+   :language: python
+
+The method
+:meth:`tooz.coordination.CoordinationDriver.watch_elected_as_leader` allows
+to register for a function to be called back when the member is elected as a
+leader. Using this function indicates that the run is therefore running for
+the election. The member can stop running by unregistering all its callbacks
+with :meth:`tooz.coordination.CoordinationDriver.unwatch_elected_as_leader`.
+It can also temporarily try to step down as a leader with
+:meth:`tooz.coordination.CoordinationDriver.stand_down_group_leader`. If
+another member is in the run for election, it may be elected instead.
+
+To retrieve the leader of a group, even when not being part of the group,
+the method :meth:`tooz.coordination.CoordinationDriver.get_leader()` can be
+used.

examples/coordinator.py

@@ -0,0 +1,5 @@
+from tooz import coordination
+
+coordinator = coordination.get_coordinator('zookeeper', b'host-1')
+coordinator.start()
+coordinator.stop()

examples/coordinator_heartbeat.py

@@ -0,0 +1,12 @@
+import time
+
+from tooz import coordination
+
+coordinator = coordination.get_coordinator('memcached', b'host-1')
+coordinator.start()
+
+while True:
+    coordinator.heartbeat()
+    time.sleep(0.1)
+
+coordinator.stop()

examples/group_membership.py

@@ -0,0 +1,14 @@
+from tooz import coordination
+
+coordinator = coordination.get_coordinator('zookeeper', b'host-1')
+coordinator.start()
+
+# Create a group
+request = coordinator.create_group(b"my group")
+request.get()
+
+# Join a group
+request = coordinator.join_group(b"my group")
+request.get()
+
+coordinator.stop()

examples/group_membership_watch.py

@@ -0,0 +1,18 @@
+from tooz import coordination
+
+coordinator = coordination.get_coordinator('zookeeper', b'host-1')
+coordinator.start()
+
+# Create a group
+request = coordinator.create_group(b"my group")
+request.get()
+
+
+def group_joined(event):
+    # Event is an instance of tooz.coordination.MemberJoinedGroup
+    print(event.group_id, event.member_id)
+
+
+coordinator.watch_join_group(b"my group", group_joined)
+
+coordinator.stop()

examples/leader_election.py

@@ -0,0 +1,28 @@
+from tooz import coordination
+
+coordinator = coordination.get_coordinator('zookeeper', b'host-1')
+coordinator.start()
+
+# Create a group
+request = coordinator.create_group(b"my group")
+request.get()
+
+# Join a group
+request = coordinator.join_group(b"my group")
+request.get()
+
+
+def when_i_am_elected_leader(event):
+    # event is a LeaderElected event
+    print(event.group_id, event.member_id)
+
+
+# Propose to be a leader for the group
+coordinator.watch_elected_as_leader(b"my_group",
+                                    when_i_am_elected_leader)
+
+while True:
+    coordinator.heartbeat()
+    coordinator.run_watchers()
+
+coordinator.stop()

setup.cfg

@@ -27,3 +27,8 @@ tooz.backends =
     kazoo = tooz.drivers.zookeeper:KazooDriver
     zake = tooz.drivers.zookeeper:ZakeDriver
     memcached = tooz.drivers.memcached:MemcachedDriver
+
+[build_sphinx]
+all_files = 1
+build-dir = doc/build
+source-dir = doc/source

test-requirements.txt

@@ -2,6 +2,7 @@ pep8>=1.4.5
 pyflakes>=0.7.2,<0.7.4
 flake8>=2.1.0
 discover
+sphinx>=1.1.2,<1.2
 python-subunit
 testrepository>=0.0.17
 testtools>=0.9.32

tox.ini

@@ -24,5 +24,5 @@ commands =
 
 [flake8]
 ignore = H405
-exclude=.venv,.git,.tox,dist,*egg,*.egg-info,build
+exclude=.venv,.git,.tox,dist,*egg,*.egg-info,build,examples,doc
 show-source = True