Added a sample IDatasetForm to show how we can implement a custom form from a plugin.
Added a sample IDatasetForm to show how we can implement a custom form from a plugin.

Currently the form is pretty ugly and the controller_plugin needs simplifying so that it makes a more sensible example. The setup.py has had the plugins section changed and the version upgraded to 0.2 ready for when it is complete

file:a/README.rst -> file:b/README.rst
This CKAN Extension demonstrates some common patterns for customising a CKAN instance. This CKAN Extension demonstrates some common patterns for customising a CKAN instance.
   
It comprises: It comprises:
   
* A CKAN Extension "plugin" at ``ckanext/example/plugin.py`` which, when * A CKAN Extension "plugin" at ``ckanext/example/plugin.py`` which, when
loaded, overrides various settings in the core ``ini``-file to provide: loaded, overrides various settings in the core ``ini``-file to provide:
   
* A path to local customisations of the core templates and stylesheets * A path to local customisations of the core templates and stylesheets
* A "stream filter" that replaces arbitrary strings in rendered templates * A "stream filter" that replaces arbitrary strings in rendered templates
* A "route" to override and extend the default behaviour of a core CKAN page * A "route" to override and extend the default behaviour of a core CKAN page
   
* A custom Pylons controller for overriding some core CKAN behaviour * A custom Pylons controller for overriding some core CKAN behaviour
   
* A custom Package edit form * A custom Package edit form
   
* A custom User registration and edition form * A custom User registration and edition form
   
* Some simple template customisations * Some simple template customisations
   
Installation Installation
============ ============
   
To install this package, from your CKAN virtualenv, run the following from your CKAN base folder (e.g. ``pyenv/``):: To install this package, from your CKAN virtualenv, run the following from your CKAN base folder (e.g. ``pyenv/``)::
   
pip install -e git+https://github.com/okfn/ckanext-example#egg=ckanext-example pip install -e git+https://github.com/okfn/ckanext-example#egg=ckanext-example
   
Then activate it by setting ``ckan.plugins = example`` in your main ``ini``-file. Then activate it by setting ``ckan.plugins = example`` in your main ``ini``-file.
   
   
Orientation Orientation
=========== ===========
   
* Examine the source code, starting with ``ckanext/example/plugin.py`` * Examine the source code, starting with ``ckanext/example/plugin.py``
   
* To understand the nuts and bolts of this file, which is a CKAN * To understand the nuts and bolts of this file, which is a CKAN
*Extension*, read in conjunction with the "Extension *Extension*, read in conjunction with the "Extension
documentation": http://docs.ckan.org/en/latest/plugins.html documentation": http://docs.ckan.org/en/latest/plugins.html
   
* One thing the extension does is set the values of * One thing the extension does is set the values of
``extra_public_paths`` and ``extra_template_paths`` in the CKAN ``extra_public_paths`` and ``extra_template_paths`` in the CKAN
config, which are "documented config, which are "documented
here": http://docs.ckan.org/en/latest/configuration.html#extra-template-paths here": http://docs.ckan.org/en/latest/configuration.html#extra-template-paths
   
* These are set to point at directories within * These are set to point at directories within
``ckanext/example/theme/`` (in this package). Here we: ``ckanext/example/theme/`` (in this package). Here we:
* override the home page HTML ``ckanext/example/theme/templates/home/index.html`` * override the home page HTML ``ckanext/example/theme/templates/home/index.html``
* provide some extra style by serving ``extra.css`` (which is loaded using the ``ckan.template_head_end`` option * provide some extra style by serving ``extra.css`` (which is loaded using the ``ckan.template_head_end`` option
* customise the navigation and header of the main template in the file ``layout.html``. * customise the navigation and header of the main template in the file ``layout.html``.
   
The latter file is a great place to make global theme alterations. The latter file is a great place to make global theme alterations.
It uses the _layout template_ pattern "described in the Genshi It uses the _layout template_ pattern "described in the Genshi
documentation":http://genshi.edgewall.org/wiki/GenshiTutorial#AddingaLayoutTemplate. documentation":http://genshi.edgewall.org/wiki/GenshiTutorial#AddingaLayoutTemplate.
This allows you to use Xpath selectors to override snippets of HTML This allows you to use Xpath selectors to override snippets of HTML
globally. globally.
   
  * The custom package edit form at ``package_form.py`` follows a deprecated
  way to make a form (using FormAlchemy). This part of the Example Theme needs
  updating. In the meantime, follow the instructions at:
  http://readthedocs.org/docs/ckan/en/latest/forms.html
   
   
  import logging
  from ckan.lib.base import BaseController, render, c, model, abort, request
  from ckan.lib.base import redirect, _, config, h
  import ckan.logic.action.create as create
  import ckan.logic.action.update as update
  import ckan.logic.action.get as get
  from ckan.logic.converters import date_to_db, date_to_form, convert_to_extras, convert_from_extras
  from ckan.lib.navl.dictization_functions import DataError, flatten_dict, unflatten
  from ckan.logic import NotFound, NotAuthorized, ValidationError
  from ckan.logic import tuplize_dict, clean_dict, parse_params
  from ckan.logic.schema import package_form_schema
  from ckan.plugins import IDatasetForm
  from ckan.plugins import implements, SingletonPlugin
  from ckan.lib.package_saver import PackageSaver
  from ckan.lib.field_types import DateType, DateConvertError
  from ckan.authz import Authorizer
  from ckan.lib.navl.dictization_functions import Invalid
  from ckanext.dgu.forms.package_gov_fields import GeoCoverageType
  from ckan.lib.navl.dictization_functions import validate, missing
  import ckan.logic.validators as val
  import ckan.logic.schema as default_schema
  from ckan.lib.navl.validators import (ignore_missing,
  not_empty,
  empty,
  ignore,
  keep_extras,
  )
 
  log = logging.getLogger(__name__)
 
  geographic_granularity = [('', ''),
  ('national', 'national'),
  ('regional', 'regional'),
  ('local authority', 'local authority'),
  ('ward', 'ward'),
  ('point', 'point'),
  ('other', 'other - please specify')]
 
  update_frequency = [('', ''),
  ('never', 'never'),
  ('discontinued', 'discontinued'),
  ('annual', 'annual'),
  ('quarterly', 'quarterly'),
  ('monthly', 'monthly'),
  ('other', 'other - please specify')]
 
  temporal_granularity = [("",""),
  ("year","year"),
  ("quarter","quarter"),
  ("month","month"),
  ("week","week"),
  ("day","day"),
  ("hour","hour"),
  ("point","point"),
  ("other","other - please specify")]
 
 
  class ExamplePackageController(SingletonPlugin):
 
  implements(IDatasetForm, inherit=True)
 
  def package_form(self):
  return 'controller/package_plugin.html'
 
  def is_fallback(self):
  """
  Returns true iff this provides the fallback behaviour, when no other
  plugin instance matches a package's type.
 
  As this is not the fallback controller we should return False. If
  we were wanting to act as the fallback, we'd return True
  """
  return False
 
  def package_types(self):
  """
  Returns an iterable of package type strings.
 
  If a request involving a package of one of those types is made, then
  this plugin instance will be delegated to.
 
  There must only be one plugin registered to each package type. Any
  attempts to register more than one plugin instance to a given package
  type will raise an exception at startup.
  """
  return ["example"]
 
  def _setup_template_variables(self, context, data_dict=None):
  c.licences = [('', '')] + model.Package.get_license_options()
  c.geographic_granularity = geographic_granularity
  c.update_frequency = update_frequency
  c.temporal_granularity = temporal_granularity
 
  c.publishers = self.get_publishers()
 
  c.is_sysadmin = Authorizer().is_sysadmin(c.user)
  c.resource_columns = model.Resource.get_columns()
 
  ## This is messy as auths take domain object not data_dict
  pkg = context.get('package') or c.pkg
  if pkg:
  c.auth_for_change_state = Authorizer().am_authorized(
  c, model.Action.CHANGE_STATE, pkg)
 
  def _form_to_db_schema(self):
 
  schema = {
  'title': [not_empty, unicode],
  'name': [not_empty, unicode, val.name_validator, val.package_name_validator],
  'notes': [not_empty, unicode],
 
  'date_released': [date_to_db, convert_to_extras],
  'date_updated': [date_to_db, convert_to_extras],
  'date_update_future': [date_to_db, convert_to_extras],
  'update_frequency': [use_other, unicode, convert_to_extras],
  'update_frequency-other': [],
  'precision': [unicode, convert_to_extras],
  'geographic_granularity': [use_other, unicode, convert_to_extras],
  'geographic_granularity-other': [],
  'geographic_coverage': [ignore_missing, convert_geographic_to_db, convert_to_extras],
  'temporal_granularity': [use_other, unicode, convert_to_extras],
  'temporal_granularity-other': [],
  'temporal_coverage-from': [date_to_db, convert_to_extras],
  'temporal_coverage-to': [date_to_db, convert_to_extras],
  'url': [unicode],
  'taxonomy_url': [unicode, convert_to_extras],
 
  'resources': default_schema.default_resource_schema(),
 
  'published_by': [not_empty, unicode, convert_to_extras],
  'published_via': [ignore_missing, unicode, convert_to_extras],
  'author': [ignore_missing, unicode],
  'author_email': [ignore_missing, unicode],
  'mandate': [ignore_missing, unicode, convert_to_extras],
  'license_id': [ignore_missing, unicode],
  'tag_string': [ignore_missing, val.tag_string_convert],
  'national_statistic': [ignore_missing, convert_to_extras],
  'state': [val.ignore_not_admin, ignore_missing],
 
  'log_message': [unicode, val.no_http],
 
  '__extras': [ignore],
  '__junk': [empty],
  }
  return schema
 
  def _db_to_form_schema(data):
  schema = {
  'date_released': [convert_from_extras, ignore_missing, date_to_form],
  'date_updated': [convert_from_extras, ignore_missing, date_to_form],
  'date_update_future': [convert_from_extras, ignore_missing, date_to_form],
  'update_frequency': [convert_from_extras, ignore_missing, extract_other(update_frequency)],
  'precision': [convert_from_extras, ignore_missing],
  'geographic_granularity': [convert_from_extras, ignore_missing, extract_other(geographic_granularity)],
  'geographic_coverage': [convert_from_extras, ignore_missing, convert_geographic_to_form],
  'temporal_granularity': [convert_from_extras, ignore_missing, extract_other(temporal_granularity)],
  'temporal_coverage-from': [convert_from_extras, ignore_missing, date_to_form],
  'temporal_coverage-to': [convert_from_extras, ignore_missing, date_to_form],
  'taxonomy_url': [convert_from_extras, ignore_missing],
 
  'resources': default_schema.default_resource_schema(),
  'extras': {
  'key': [],
  'value': [],
  '__extras': [keep_extras]
  },
  'tags': {
  '__extras': [keep_extras]
  },
 
  'published_by': [convert_from_extras, ignore_missing],
  'published_via': [convert_from_extras, ignore_missing],
  'mandate': [convert_from_extras, ignore_missing],
  'national_statistic': [convert_from_extras, ignore_missing],
  '__extras': [keep_extras],
  '__junk': [ignore],
  }
  return schema
 
  def _check_data_dict(self, data_dict):
  return
 
  def get_publishers(self):
  return [('pub1', 'pub2')]
 
 
  def use_other(key, data, errors, context):
 
  other_key = key[-1] + '-other'
  other_value = data.get((other_key,), '').strip()
  if other_value:
  data[key] = other_value
 
  def extract_other(option_list):
 
  def other(key, data, errors, context):
  value = data[key]
  if value in dict(option_list).keys():
  return
  elif value is missing:
  data[key] = ''
  return
  else:
  data[key] = 'other'
  other_key = key[-1] + '-other'
  data[(other_key,)] = value
  return other
 
  def convert_geographic_to_db(value, context):
 
  if isinstance(value, list):
  regions = value
  elif value:
  regions = [value]
  else:
  regions = []
 
  return GeoCoverageType.get_instance().form_to_db(regions)
 
  def convert_geographic_to_form(value, context):
 
  return GeoCoverageType.get_instance().db_to_form(value)
 
  <form id="package-edit" class="package_create_form ckan" method="post"
  py:attrs="{'class':'has-errors'} if errors else {}"
  xmlns:i18n="http://genshi.edgewall.org/i18n"
  xmlns:py="http://genshi.edgewall.org/"
  xmlns:xi="http://www.w3.org/2001/XInclude">
 
  <div class="error-explanation" py:if="error_summary">
  <h2>Errors in form</h2>
  <p>The form contains invalid entries:</p>
  <ul>
  <li py:for="key, error in error_summary.items()">${"%s: %s" % (key, error)}</li>
  </ul>
  </div>
 
  <fieldset>
  <legend>Example Basic information</legend>
  <dl>
  <dt><label class="field_req" for="title">Title *</label></dt>
  <dd><input id="title" name="title" type="text" value="${data.get('title', '')}"/></dd>
  <dd class="instructions basic">The title of the data set.</dd>
  <dd class="instructions further">The main subject of the data should be clear. For cross-government data requirements, such as spend data, specify the public body the data belongs to or its geographical coverage, in order to distinguish your data from other similar datasets in data.gov.uk. If the data relates to a period of time, include that in the name, although this would not be appropriate for data which is updated over time. It is not a description - save that for the Abstract element. Do not give a trailing full stop.</dd>
  <dd class="hints">e.g. Payments to suppliers with a value over &pound;500 from Harlow Council</dd>
  <dd class="field_error" py:if="errors.get('title', '')">${errors.get('title', '')}</dd>
 
  <dt><label class="field_req" for="name">Identifier *</label></dt>
  <dd><input id="name" maxlength="100" name="name" type="text" value="${data.get('name', '')}" /></dd>
  <dd class="instructions basic">A public unique identifier for the dataset</dd>
  <dd class="instructions further">It should be roughly readable, with dashes separating words.</dd>
  <dd class="hints">Format: Two or more lowercase alphanumeric, dash (-) or underscore (_) characters. e.g. uk-road-traffic-statistics-2008 or local-authority-spend-over-500-harlow</dd>
  <dd class="field_error" py:if="errors.get('name', '')">${errors.get('name', '')}</dd>
 
  <dt><label class="field_req" for="notes">Abstract *</label></dt>
  <dd><textarea cols="60" id="notes" name="notes" rows="15">${data.get('notes', '')}</textarea></dd>
  <dd class="instructions basic">The main description of the dataset</dd>
  <dd class="instructions further">It is often displayed with the package title. In particular, it should start with a short sentence that describes the data set succinctly, because the first few words alone may be used in some views of the data sets. Here is the place to state if there are any limitations or deficiencies to the data in order to enable users to evaluate the information; even incomplete data may be adequate for some users.</dd>
  <dd class="field_error" py:if="errors.get('notes', '')">${errors.get('notes', '')}</dd>
  </dl>
  </fieldset>
 
  <fieldset>
  <legend>Example Details</legend>
  <dl>
  <dt><label class="field_opt" for="date_released">Date released</label></dt>
  <dd><input id="date_released" name="date_released" size="40" type="text" value="${data.get('date_released', '')}" /></dd>
  <dd class="instructions basic">The date of the official release of the initial version of the dataset</dd>
  <dd class="instructions further">This is probably not the date that it is uploaded to data.gov.uk. Be careful not to confuse a new 'version' of some data with a new dataset covering another time period or geographic area.</dd>
  <dd class="hints">DD/MM/YYYY</dd>
  <dd class="field_error" py:if="errors.get('date_released', '')">${errors.get('date_released', '')}</dd>
 
  <dt><label class="field_opt" for="date_updated">Date updated</label></dt>
  <dd><input id="date_updated" name="date_updated" size="40" type="text" value="${data.get('date_updated', '')}"/></dd>
  <dd class="instructions basic">The date of release of the most recent version of the dataset</dd>
  <dd class="instructions further">This is not necessarily the date when it was updated on data.gov.uk. As with 'Date released', this is for updates to a particular dataset, such as corrections or refinements, not for that of a new time period.</dd>
  <dd class="hints">DD/MM/YYYY</dd>
  <dd class="field_error" py:if="errors.get('date_updated', '')">${errors.get('date_updated', '')}</dd>
 
  <dt><label class="field_opt" for="date_update_future">Date to be published</label></dt>
  <dd><input id="date_update_future" name="date_update_future" size="40" type="text" value="${data.get('date_update_future', '')}"/></dd>
  <dd class="instructions basic">When the dataset will be updated in the future, if appropriate</dd>
  <dd class="hints">DD/MM/YYYY</dd>
  <dd class="field_error" py:if="errors.get('date_updated', '')">${errors.get('date_updated', '')}</dd>
 
  <dt><label class="field_opt" for="update_frequency">Update frequency</label></dt>
  <dd>
  <select class="short" id="update_frequency" name="update_frequency">
  <py:for each="freq_name, freq_desc in c.update_frequency">
  <option value="${freq_name}" py:attrs="{'selected': 'selected' if data.get('update_frequency', '') == freq_name else None}" >
  ${freq_desc}