I want to be able to change the condition statement of a WF4 Workflow If-Activtity runtime, where the input comes from some sort of user interface as a string. I have read up on how to change a Workflow dynamically, or how to create Activites from code - the problem comes when I get to the point of assigning the Condition-property to the If-activity class. My source is a string. The constructor does not take a string.
Do I have to convert the string to an Expression<bool> first? How do I do that?
This is the string I want to expose
Note: I realize there may be other ways to accomplish what I want, like (1) create code that alters the XAML of the Workflow instead of the objects, or (2) exposing the entire Workflow editor to the end user. Before I go down that road, I want to know if it is possible to do it my way.
You can use a expression like
new VisualBasicValue<bool>("Person.Gender = \"Male\"")
A warning: The Apply Workflow Changes to Workflows you are pointing to is about WF3 and has no bearing in WF4 whatsoever. With WF4 there is no possibility to dynamically change a running workflow instance. That capability is going to be added in the .NET 4.5 framework.
Related
I like the simplicity of Pundit gem and I would like to make policies dynamic by storing them to database.
Basically I'm looking for a way to be able to change policies without need to redeploy the application.
1st way
Pundit policy is pure ruby code, so if you don't want to keep code inside database and evaluate it dynamically, I'd say the answer is no. It's unsafe. You may give it a go, though.
2nd way
But nothing prevents you from creating model which keeps rules in simple json and compare them using Pundit, e.g.:
class PostPolicy < ApplicationPolicy
def update?
access_setting = PolicySetting.find_by(key: self.class_name)
user.role.in?(access_setting['roles'])
end
end
Of course, complexity and flexibility of the tool directly depends on each other.
3rd way
Is just work around. You may set you authorisation project apart from the main one, so that it's deploys (zero-downtime, of course) would not affect the main big project.
4th way
Create your own DSL to be stored in Database
5th way
Use something like json-logic-ruby to store logic in database
I've been trying to implement a Front Controller on a VBScript (ASP Classic) based system for a couple of days. I come from a ASP.NET MVC and Java background, where MVC implementations are kind common and mostly done by existing frameworks. On VBScript, however, there's almost nothing done in this area, so it is the reason why I'm trying to do it by myself. I used this and this article as a guide on how to implement it.
I believed at first that I'd need to define some constant parameters for each request, so I created 3:
class_command 'which command responsible to execute the correct class handler
action 'which method of the class handler to execute
action_params 'which parameters the action will need
Next, I defined a generic controller handler for treating the request:
Public Function Controller_Handler(action_params)
Its task is to extract the constant parameters (class_command, action, action_params) and treat any errors (I'll add later a filter to process it) that might come like absence of the constant parameters or authentication problems.
But soon I realized a problem: how will the handler know which command to call, since the request is a string? I can't simply converting it to class using reflection, because VBScript (I think) doesn't have a reflection library or built-in feature.
So I thought I could create a Switch Case like this:
Select action_Params.Item("action_params")
Case "command_A"
' Call Command A
Case "command_B"
' Call Command_B
.
.
.
Case "Command_X"
' And so on
End Select
But that would kinda procedural way to do it. Next I thought of creating a XML file which would map all the commands and other stuff.
So my question is: is this a good way of implementing a Front Controlller pattern, considering VBScript limitations? If not, could you provide a guidance (hopefully with some example, even a simple one) on how can I do it?
Moving from classic to .net/mvc I can share what I did in classic asp to try to emulate this behavior as closely as possible without making it too much of a maintenance issue.
Using URL Rewrite in IIS are my routes. I usually just make one route and direct/rewrite all inbound requests to one controller.asp page to simplify things and not have a bunch of rules and controller redirects directly in my URL Rewrite settings for maintaining it easier (for me).
Using Request.ServerVariables("HTTP_X-ORIGINAL-URL") in controllers.asp you can grab the actual URL that was entered, which return something like.. /real/url
In controllers.asp programatically call the view based on the entered url using Server.Execute("view1.asp")
I have one class file called routes.asp that is included in each model/class file, and helps me gather the URL properties oRoute.GetPath_FirstDirectory() and so on. The model/class file then uses this data to create its property values that can be consumed by the view. Using CLASS_INITIALIZE in each model/class to populate itself from the route/url, or it could also be done directly in the view.
In the respective view I include my class/model file (if even needed) using <!--#include file="class.asp"--> then simply open Set Model = new cModelClass to initialize and start using it in the view. I don't include the class in the controllers.asp because the view will not inherit any of the variables from controllers.asp when using Server.Execute() to the view. So I include it directly in the view.
Error handling can be at multiple levels here, but ideally its in the controllers.asp. Specific error handling is usually at the actual model/class CLASS_INITIALIZE to avoid redundant use of the class in the controller, since it's already going to be initialized in the view.
Now this is not exactly what goes in in .Net mvc, but it's the best way I've come up with, and easiest to maintain for me. Maybe others have other implementations, but this is mine and solely based on my experience. And so far, it's been working out pretty well.
I'm deleting an instance of an entity and depending on the value of an option set in it, I wish to carry our different course of action. The problem is that the field isn't changed, hence, not provided to the plugin's target.
How can I easily tell the stupid plugin to fetch all the fields?
The way I do it now is to use pre-image but I'll be showing the plugin to some rookies and they will definitely not like it. And they won't believe me that's the way to go, for sure, because they're a cocky bunch.
Is there a work-around for that?
Using the pre-image is the suggested way in this scenario, the alternative is to instantiate a service factory in order to get an IOrganizationService and retrieve the entity using the target's Id.
It is part of the IPluginExecutionContext (of which Target is one part.) I think the beginners are confused if they think of Target as anything more than a property of IPluginExecutionContext.
It wouldn't make sense to have these values as part of Target, because then it would cause an update of the field to its current value - if you forced it into Target you would see the update in the audit details.
Thus, CRM has PreEntityImages, Target, and PostEntityImages, if Target was used the way "they" want it would not be able to differentiate between values being updated, previous values, and the final result of the entity.
I am trying to create a Visual Studio extension which handles a multi-language content type. Much like some mvc-templates and Django or ASP.NET which a certain part of the code is in another language.
I know that I should use Projection and I already checked Django for Visual Studio extension but the solution there includes creating a Language Service and going to the trouble of creating all bits and pieces related to a code editor. Here I am trying to achieve the same goal just by using MEF.
I know that you can use IProjectionBuffer CreateProjectionBuffer() to create a projection but the question is how to replace the current TextBuffer with the created one and when is the best time to do it.
Also one may expect that if he specifies a base definition of type "projection" like this:
[Export]
[Name("Whatever")]
[BaseDefinition("code")]
[BaseDefinition("projection")]
internal static ContentTypeDefinition WhateverContentType = null;
the received TextBuffer in providers to be of type IProjectionBuffer (after all IProjectionBuffer is inherited from ITextBuffer). Which are not and it seems that a projection base definition has no effect what so ever.
So if I want to rephrase my question in a tldr version:
How and when do you apply an IProjectionBuffer to current view (using MEF and without creating an editor instance)?
So if I understand your question correctly, the answer is "you don't." A IWpfTextView is bound to a implementation of ITextBuffer (or a derived type, like IProjectionBuffer) at creation time, and can't be changed. Even if you could, many other extensions and language services would be most surprised by this and would probably crash.
To address your second question about content types: simply declaring you have a base content type of "projection" doesn't make you a projection buffer. All that really states is you might be creating projection buffers of that type, and when you do you want some extra ITagger support so taggers project through to the source buffers as you might expect them to.
Right now I am doing my testing by creating a controller for passing in the name of the file, parsing the file in the model and adding the necessary information added as a row in my database, which is then displayed on a page. I am then comparing the fields on the page to what the fields should be.
But this seems messy since the controller and display page were created only for the purposes of these tests. Is there a way to just feed the file name into a method in my model, and then run the usual tests against the database info itself?
I think it would be easier to answer this if we had a code sample (of the controller and model) to see why this shouldn't be handled in the standard rspec idiom.
Without knowing about your controller or model, I can at least say this: Yes, you can do that. The basic procedure to follow is to create your test file (if you need to), feed the name/path in to the test using a standard variable (yes, most likely hard coded, though it depends on how extensive you're planning to be), then test it against your database in whatever your standard way to do such things is.