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 plugin that allows for custom forms to be used for datasets based on | |
their "type". | |
* 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 | * 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 | way to make a form (using FormAlchemy). This part of the Example Theme needs |
updating. In the meantime, follow the instructions at: | updating. In the meantime, follow the instructions at: |
http://readthedocs.org/docs/ckan/en/latest/forms.html | http://readthedocs.org/docs/ckan/en/latest/forms.html |
import os, logging | |
from ckan.authz import Authorizer | |
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.logic import NotFound, NotAuthorized, ValidationError | |
from ckan.logic import tuplize_dict, clean_dict, parse_params | |
import ckan.logic.schema as default_schema | |
from ckan.logic.schema import package_form_schema | |
import ckan.logic.validators as val | |
from ckan.lib.base import BaseController, render, c, model, abort, request | |
from ckan.lib.base import redirect, _, config, h | |
from ckan.lib.package_saver import PackageSaver | |
from ckan.lib.field_types import DateType, DateConvertError | |
from ckan.lib.navl.dictization_functions import Invalid | |
from ckan.lib.navl.dictization_functions import validate, missing | |
from ckan.lib.navl.dictization_functions import DataError, flatten_dict, unflatten | |
from ckan.plugins import IDatasetForm, IConfigurer | |
from ckan.plugins import implements, SingletonPlugin | |
from ckan.lib.navl.validators import (ignore_missing, | |
not_empty, | |
empty, | |
ignore, | |
keep_extras, | |
) | |
log = logging.getLogger(__name__) | |
class ExampleDatasetForm(SingletonPlugin): | |
"""This plugin demonstrates how a theme packaged as a CKAN | |
extension might extend CKAN behaviour. | |
In this case, we implement three extension interfaces: | |
- ``IConfigurer`` allows us to override configuration normally | |
found in the ``ini``-file. Here we use it to specify where the | |
form templates can be found. | |
- ``IDatasetForm`` allows us to provide a custom form for a dataset | |
based on the type_name that may be set for a package. Where the | |
type_name matches one of the values in package_types then this | |
class will be used. | |
""" | |
implements(IDatasetForm, inherit=True) | |
implements(IConfigurer, inherit=True) | |
def update_config(self, config): | |
""" | |
This IConfigurer implementation causes CKAN to look in the | |
```templates``` directory when looking for the package_form() | |
""" | |
here = os.path.dirname(__file__) | |
rootdir = os.path.dirname(os.path.dirname(here)) | |
template_dir = os.path.join(rootdir, 'ckanext', | |
'example', 'theme', 'templates') | |
config['extra_template_paths'] = ','.join([template_dir, | |
config.get('extra_template_paths', '')]) | |
def package_form(self): | |
""" | |
Returns a string representing the location of the template to be | |
rendered. e.g. "package/new_package_form.html". | |
""" | |
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): | |
""" | |
Adds variables to c just prior to the template being rendered that can | |
then be used within the form | |
""" | |
c.licences = [('', '')] + model.Package.get_license_options() | |
c.publishers = [('Example publisher', 'Example publisher 2')] | |
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): | |
""" | |
Returns the schema for mapping package data from a form to a format | |
suitable for the database. | |
""" | |
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], | |
'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): | |
""" | |
Returns the schema for mapping package data from the database into a | |
format suitable for the form (optional) | |
""" | |
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], | |
'precision': [convert_from_extras, ignore_missing], | |
'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): | |
""" | |
Check if the return data is correct and raises a DataError if not. | |
""" | |
return | |
<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()">${"%s: %s" % (key, error)}</li> | |
</ul> | |
</div> | |
<fieldset> | |
<legend>Basic information</legend> | |
<dl> | |
<dt><label class="field_req" for="title">Title *</label></dt> | |
<dd><input id="title" name="title" type="text" value="${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 £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', '')">${errors.get('notes', '')}</dd> | |
</dl> | |
</fieldset> | |
<fieldset> | |
<legend>Details</legend> | |
<dl> | |
<dt><label class="field_opt" for="date_released">Date released</label></dt> | |
<dd><input id="date_released" name="date_released" size="40" type="text" value="${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 the date that the data was officially released</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}" > | |
${freq_desc} | |
</option> | |
</py:for> | |
</select> | |
<label class="inline" for="update_frequency-other">Other: | |
<input class="medium-width" id="update_frequency-other" name="update_frequency-other" type="text" value="${data.get('update_frequency-other', '')}"/> | |
</label> | |
</dd> | |
<dd class="instructions basic">How frequently the dataset is updated with new versions</dd> | |
<dd class="instructions further">For one-off data, use 'never'. For those once updated but now discontinued, use 'discontinued'.</dd> | |
<dd class="field_error" py:if="errors.get('update_frequency', '')">${errors.get('update_frequency', '')}</dd> | |
<dt><label class="field_opt" for="precision">Precision</label></dt> | |
<dd><input id="precision" name="precision" size="40" type="text" value="${data.get('precision', '')}"/></dd> | |
<dd class="instructions basic">Indicate the level of precision in the data, to avoid over-interpretation.</dd> | |
<dd class="hints">e.g. 'per cent to two decimal places' or 'as supplied by respondents'</dd> | |
<dt><label class="field_opt" for="url">URL</label></dt> | |
<dd><input id="url" name="url" type="text" value="${data.get('url', '')}"/></dd> | |
<dd class="instructions basic">The Internet link to a web page discussing the dataset.</dd> | |
<dd class="hints">e.g. http://www.somedept.gov.uk/growth-figures.html</dd> | |
<dd class="field_error" py:if="errors.get('url', '')">${errors.get('url', '')}</dd> | |
<dt><label class="field_opt" for="taxonomy_url">Taxonomy URL</label></dt> | |
<dd><input id="taxonomy_url" name="taxonomy_url" size="40" type="text" value="${data.get('taxonomy_url', '')}"/></dd> | |
<dd class="instructions basic">An Internet link to a web page describing the taxonomies used in the dataset, if any, to ensure they understand any terms used.</dd> | |
<dd class="hints">e.g. http://www.somedept.gov.uk/growth-figures-technical-details.html</dd> | |
<dd class="field_error" py:if="errors.get('taxonomy_url', '')">${errors.get('taxonomy_url', '')}</dd> | |
</dl> | |
</fieldset> | |
<fieldset> | |
<legend>Resources</legend> | |
<table class="flexitable">< |