Routes enhancements

gistfile1.py

"Fixes and enhancements to Routes 1.11 - see http://positiveincline.com/?p=561"

# NB: superceded by http://bitbucket.org/asplake/routes/

import routes.mapper

COLLECTION_ACTIONS = ['index', 'create', 'new']
MEMBER_ACTIONS = ['show', 'update', 'delete', 'edit']

class SubMapperParent(object):
    def submapper(self, **kwargs):
        return SubMapper(self, **kwargs)

    def collection(
                self, 
                collection_name,
                resource_name,
                path_prefix=None,
                member_prefix='/{id}',
                controller=None,
                collection_actions=COLLECTION_ACTIONS,
                member_actions = MEMBER_ACTIONS,
                member_options=None,
                **kwargs):
                    
        if not controller:
            controller =resource_name or collection_name
        
        if not path_prefix:
            path_prefix = '/' + collection_name
    
        collection = SubMapper(
                            self,
                            collection_name=collection_name,
                            resource_name=resource_name,
                            path_prefix = path_prefix,
                            controller=controller,
                            actions=collection_actions,
                            **kwargs)
        
        collection.member = SubMapper(
                                collection,
                                path_prefix = member_prefix,
                                actions=member_actions,
                                **(member_options or {}))

        return collection

# Define a new Mapper that knows about our enhanced SubMapper
class Mapper(SubMapperParent, routes.Mapper):
    # Pretty string representation
    def __str__(self):
        def format_methods(r):
            if r.conditions:
                method = r.conditions.get('method', '')
                return method if type(method) is str else ', '.join(method)
            else:
                return ''

        table = [('Route name', 'Methods', 'Path')] + [
            (
                r.name or '',
                format_methods(r),
                r.routepath or ''
            )
            for r in self.matchlist]
            
        widths = [
            max(len(row[col]) for row in table)
            for col in range(len(table[0]))]
        
        return '\n'.join(
            ' '.join(row[col].ljust(widths[col]) for col in range(len(widths)))
            for row in table)

# Add some new tricks to SubMapper
class SubMapper(SubMapperParent, routes.mapper.SubMapper):
    # Save a resource name on initialisation, defaulting it to the controller name
    def __init__(self, obj, resource_name=None, collection_name=None, actions=None, **kwargs):
        routes.mapper.SubMapper.__init__(self, obj, **kwargs)
        
        self.collection_name = collection_name
        self.member = None
        self.resource_name = resource_name \
                            or getattr(obj, 'resource_name', None) \
                            or kwargs.get('controller', None) \
                            or getattr(obj, controller, None)

        self.add_actions(actions or [])

    # Fix known bug, support merging of dict-valued options (needed for nested collections)
    def connect(self, *args, **kwargs):
        newkargs = {}
        newargs = args
        for key, value in self.kwargs.items():
            if key == 'path_prefix':
                if len(args) > 1:  # was len(args > 1)
                    newargs = (args[0], value + args[1])
                else:
                    newargs = (value + args[0],)
            elif key in kwargs:
                if isinstance(value, dict):
                    newkargs[key] = dict(value, **kwargs[key]) # merge dicts
                else:
                    newkargs[key] = value + kwargs[key]
            else:
                newkargs[key] = self.kwargs[key]
        for key in kwargs:
            if key not in self.kwargs:
                newkargs[key] = kwargs[key]
        return self.obj.connect(*newargs, **newkargs)
    
    # Generate a subresource linked by "rel", e.g.
    # 
    #     with mapper.submapper(controller='thing', path_prefix='/things') as c:
    #        c.link('new')
    #        with c.submapper(path_prefix='/{id}')) as m:
    #            m.link('edit')
    #
    # generates
    #
    #     mapper.connect(
    #           'new_thing', '/things/edit',
    #           controller='thing', action='new',
    #           conditions={'method': 'GET'})
    #     mapper.connect(
    #           'edit_thing', '/things/{id}/edit',
    #           controller='thing', action='edit',
    #           conditions={'method': 'GET'})
    #
    # Overridable defaults:
    #     name: {rel}_{self.resource_name}
    #     action: rel
    #     rel: name  
    #     method: 'GET'
    #
    # At least one of rel and name (the route name) must be supplied.  It would
    # be unusual not to supply rel.
    #
    def link(self, rel=None, name=None, action=None, method='GET', **kwargs):
        return self.connect(
            name or (rel + '_' + self.resource_name),
            '/' + (rel or name),
            action=action or rel or name,
            **_kwargs_with_conditions(kwargs, method))

    def new(self, **kwargs):
        return self.link(rel='new', **kwargs)

    def edit(self, **kwargs):
        return self.link(rel='edit', **kwargs)

    # Generate an action (typically with the POST method) on a resource that
    # supports other methods (typically GET).
    # 
    #     with mapper.submapper(controller='thing', path_prefix='/things') as m:
    #        with m.submapper(path_prefix='/{id}')) as o:
    #            o.action('show', name='thing')
    #            o.action('update', method='PUT')
    #
    # generates
    #
    #     mapper.connect(
    #           'thing', '/things/{id}',
    #           controller='thing', action='show',
    #           conditions={'method': 'GET'})
    #     mapper.connect(
    #           'save_thing', '/things/{id}',
    #           controller='thing', action='update',
    #           conditions={'method': 'PUT'})
    #
    # Overridable defaults:
    #   name: {action}_{self.resource_name}
    #   action: name
    #   method: GET
    #
    # At least one of name (the route name) and action must be supplied.
    #
    def action(self, name=None, action=None, method='GET', **kwargs):
        return self.connect(
            name or (action + '_' + self.resource_name),
            '',
            action=action or name,
            **_kwargs_with_conditions(kwargs, method))
            
    def index(self, name=None, **kwargs):
        return self.action(
            name=name or self.collection_name,
            action='index', method='GET', **kwargs)

    def show(self, name = None, **kwargs):
        return self.action(
            name=name or self.resource_name,
            action='show', method='GET', **kwargs)

    def create(self, **kwargs):
        return self.action(action='create', method='POST', **kwargs)
        
    def update(self, **kwargs):
        return self.action(action='update', method='PUT', **kwargs)

    def delete(self, **kwargs):
        return self.action(action='delete', method='DELETE', **kwargs)

    def add_actions(self, actions):
        [getattr(self, action)() for action in actions]


# Create kwargs with a 'conditions' member generated for the given method
def _kwargs_with_conditions(kwargs, method):
    if method and 'conditions' not in kwargs:
        newkwargs = kwargs.copy()
        newkwargs['conditions'] = {'method': method}                
        return newkwargs             
    else:
        return kwargs