Python Entrouvert

import os

import json

import glob

import hashlib

class TenantSettingBaseMiddleware(object):

    '''Base middleware classe for loading settings based on tenants

       Child classes MUST override the load_tenant_settings() method.

    '''

    def __init__(self, *args, **kwargs):

        self.tenants_settings = {}

    def get_tenant_settings(self, wrapped, tenant):

        '''Get last loaded settings for tenant, try to update it by loading

           settings again is last loading time is less recent thant settings data

           store. Compare with last modification time is done in the

           load_tenant_settings() method.

        '''

        tenant_settings, last_time = self.tenants_settings.get(tenant.schema_name, (None,None))

        if tenant_settings is None:

            tenant_settings = UserSettingsHolder(wrapped)

        tenant_settings, last_time = self.load_tenant_settings(wrapped, tenant, tenant_settings, last_time)

        self.tenants_settings[tenant.schema_name] = tenant_settings, last_time

        return tenant_settings

    def load_tenant_settings(self, wrapped, tenant, tenant_settings, last_time):

        '''Load tenant settings into tenant_settings object, eventually skip if

           last_time is more recent than last update time for settings and return

           the new value for tenant_settings and last_time'''

        raise NotImplemented

    def process_request(self, request):

        if not hasattr(request, '_old_settings_wrapped'):

            request._old_settings_wrapped = []

        request._old_settings_wrapped.append(settings._wrapped)

        settings._wrapped = self.get_tenant_settings(settings._wrapped, request.tenant)

    def process_response(self, request, response):

        if hasattr(request, '_old_settings_wrapped') and request._old_settings_wrapped:

            settings._wrapped = request._old_settings_wrapped.pop()

        return response

class JSONSettingsMiddleware(TenantSettingBaseMiddleware):

    '''Load settings from a JSON file whose path is given by:

            os.path.join(settings.TENANT_BASE % schema_name, 'settings.json')

    '''

    def load_tenant_settings(self, wrapped, tenant, tenant_settings, last_time):

        path = os.path.join(settings.TENANT_BASE, tenant.schema_name, 'settings.json')

        if not os.path.exists(path):

            if last_time is not None:

                return UserSettingsHolder(wrapped), None

        else:

            new_time = os.stat(path).st_mtime

            if new_time >= last_time:

                tenant_settings = UserSettingsHolder(wrapped)

                json_settings = json.load(file(path))

                for key in json_settings:

                    setattr(tenant_settings, key, json_settings[key])

                return tenant_settings, new_time

        return tenant_settings, last_time