Module: Permissable::InstanceMethods

Defined in:
lib/permissable.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.included(base) ⇒ Object 



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# File 'lib/permissable.rb', line 135

def self.included(base)
  base.define_singleton_method(:included) do |klass|
    klass.cattr_accessor :permissions_lookup
    klass.cattr_accessor :allow_cached_permissions
    klass.cattr_accessor :default_permission_scopes
    klass.default_permission_scopes = ['full']
    klass.permissions_lookup = []
  end
end

Instance Method Details

#allows?(user, action, relevant_scopes = nil) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/permissable.rb', line 71

def allows?(user, action, relevant_scopes=nil)
  relevant_scopes ||= user.permission_scopes if user && user.respond_to?(:permission_scopes)
  relevant_scopes ||= self.class.default_permission_scopes
  relevant_scopes += ['*'] unless relevant_scopes == ['none']
  if self.class.allow_cached_permissions
    # check for an existing result keyed off the record's id and updated_at
    permissions = permissions_for(user, relevant_scopes)
    action.instance_variable_set('@scope_rejected', permissions[action] == false)
  
    return permissions[action] == true
  end

  scope_rejected = false    
  self.class.permissions_lookup.each do |actions, block, allowed_scopes|
    next unless actions.include?(action.to_s)
    next if block.arity == 1 && !user
    res = instance_exec(user, &block)
    if res == true
      if (allowed_scopes & relevant_scopes).length > 0
        return true
      else
        scope_rejected = true
      end
    end
  end
  action.instance_variable_set('@scope_rejected', !!scope_rejected)
  return false
end

#cache_key(prefix = nil) ⇒ Object 



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# File 'lib/permissable.rb', line 43

def cache_key(prefix=nil)
  id = self.id || 'nil'
  updated = (self.updated_at || Time.now).to_f
  key = "#{self.class.to_s}#{id}-#{updated}:#{Permissable.cache_token}"
  if prefix
    key = prefix + "/" + key
  end
  key
end

#clear_cached(prefix) ⇒ Object 



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# File 'lib/permissable.rb', line 67

def clear_cached(prefix)
  Permissable.permissions_redis.del(self.cache_key(prefix))
end

#get_cached(prefix) ⇒ Object 



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# File 'lib/permissable.rb', line 58

def get_cached(prefix)
  cache_string = Permissable.permissions_redis.get(self.cache_key(prefix))
  cache = nil
  if cache_string
    cache = JSON.parse(cache_string) rescue nil
  end
  cache
end

#permissions_for(user, relevant_scopes = nil) ⇒ Object 



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# File 'lib/permissable.rb', line 100

def permissions_for(user, relevant_scopes=nil)
  relevant_scopes ||= user.permission_scopes if user && user.respond_to?(:permission_scopes)
  relevant_scopes ||= self.class.default_permission_scopes
  relevant_scopes += ['*'] unless relevant_scopes == ['none']
  if self.class.allow_cached_permissions
    cache_key = (user && user.cache_key) || "nobody"
    cache_key += "/scopes_#{relevant_scopes.join(',')}"
    permissions = get_cached("permissions-for/#{cache_key}")
    return permissions if permissions
  end

  granted_permissions = {
    'user_id' => (user && user.global_id)
  }
  granted_permissions.with_indifferent_access if granted_permissions.respond_to?(:with_indifferent_access)
  
  self.class.permissions_lookup.each do |actions, block, allowed_scopes|
    already_granted = granted_permissions.select{|k, v| v == true }.map(&:first)
    next if block.arity == 1 && !user
    next if actions - already_granted == []
    if instance_exec(user, &block)
      actions.each do |action|
        if (allowed_scopes & relevant_scopes).length > 0
          granted_permissions[action] = true
        else
          granted_permissions[action] ||= false
        end
      end
    end
  end
  # cache the result with a 30-minute expiration keyed off the id and updated_at
  set_cached("permissions-for/#{cache_key}", granted_permissions) if self.class.allow_cached_permissions
  granted_permissions
end

#set_cached(prefix, data, expires = nil) ⇒ Object 



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# File 'lib/permissable.rb', line 53

def set_cached(prefix, data, expires=nil)
  expires ||= 1800 # 30 minutes
  Permissable.permissions_redis.setex(self.cache_key(prefix), expires, data.to_json)
end