Class: OpenWFE::RevalExpression

Inherits:
FlowExpression show all
Includes:
ValueMixin
Defined in:
lib/openwfe/expressions/fe_misc.rb

Overview

Evals some Ruby code contained within the process definition or within the workitem.

The code is evaluated at a SAFE level of 3.

If the :ruby_eval_allowed isn’t set to true (engine.application_context[:ruby_eval_allowed] = true), this expression will throw an exception at apply.

some examples :

<reval>
    workitem.customer_name = "doug"
    # or for short 
    wi.customer_address = "midtown 21_21 design"
</reval>

in a Ruby process definition :

sequence do
    _set :field => "customer" do
        reval """
            {
                :name => "Cheezburger",
                :age => 34,
                :comment => "I can haz ?",
                :timestamp => Time.now.to_s
            }
        """
    end
end

Don’t embed too much Ruby into your process definitions, it might hurt…

Reval can also be used with the ‘code’ attribute (or ‘field-code’ or ‘variable-code’) :

<reval field-code="f0" />

to eval the Ruby code held in the field named “f0”.

Constant Summary collapse

SAFETY_LEVEL =

See for an explanation on Ruby safety levels : www.rubycentral.com/book/taint.html

‘reval’ is entitled a safe level of 3.

3

Instance Attribute Summary

Attributes inherited from FlowExpression

#apply_time, #attributes, #children, #environment_id, #fei, #parent_id, #raw_representation

Attributes included from Contextual

#application_context

Instance Method Summary collapse

Methods included from ValueMixin

#apply, #lookup_field_attribute, #lookup_variable_attribute

Methods inherited from FlowExpression

#apply, #cancel, #clean_children, #delete_variable, #dup_environment, #fetch_environment, #fetch_text_content, #get_binding, #get_environment, #get_parent, #get_root_environment, #has_attribute, #initialize, is_definition, is_definition?, #lookup_attribute, #lookup_attributes, #lookup_boolean_attribute, #lookup_comma_list_attribute, #lookup_downcase_attribute, #lookup_ref, #lookup_string_attribute, #lookup_sym_attribute, #lookup_value, #lookup_variable, #lookup_vf_attribute, names, #new_environment, new_exp, #owns_its_environment?, #paused?, #remove_child, #reply_to_parent, #set_variable, #store_itself, #synchronize, #to_s, #to_yaml_properties

Methods included from Contextual

#get_work_directory, #init_service, #lookup

Methods included from Logging

#ldebug, #ldebug_callstack, #lerror, #lfatal, #linfo, #llog, #lunknown, #lwarn

Methods included from OwfeServiceLocator

#get_engine, #get_error_journal, #get_expool, #get_expression_map, #get_expression_pool, #get_expression_storage, #get_expression_storages, #get_journal, #get_participant_map, #get_scheduler, #get_wfid_generator

Methods inherited from ObjectWithMeta

#class_def, meta_def, meta_eval, metaclass

Constructor Details

This class inherits a constructor from OpenWFE::FlowExpression

Instance Method Details

#reply(workitem) ⇒ Object 



147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
 
# File 'lib/openwfe/expressions/fe_misc.rb', line 147

def reply (workitem)

    raise "evaluation of ruby code is not allowed" \
        if @application_context[:ruby_eval_allowed] != true

    code = lookup_vf_attribute(workitem, 'code') || workitem.get_result
    code = code.to_s

    wi = workitem 
        # so that the ruby code being evaluated sees 'wi' and 'workitem'

    result = Rufus::eval_safely code, SAFETY_LEVEL, binding()

    workitem.set_result(result) \
        if result != nil  # 'false' is a valid result

    reply_to_parent workitem
end