I am a data scientist, tasked with creating forms for user inputs to computations. These inputs include date ranges, integers, etc. Every computation describes its necessary and optional inputs. I would like to automatically turn a computation description into an HTML form, including (server side) validation of user entries. For a toy example, consider
Computation 1: Divide a by b
Description: Divide two integers!
a: int
b: int
Result: a/b
This should be turned into an HTML form asking for a, b, and the description. This form does not need to be pretty, but should look presentable. There are many graphical form building tools out there, is there also a tool allowing programmatic form building? Is there even an open source tool? Since I am not a frontend developer I would prefer to use such a tool instead of developing my own logic. I would also like to keep the validation logic on the server side (here: b!=0), necessitating the possibility to programmatically talk to the form in some way.
On a higher level, is this even the right way to go about creating UIs for computations defining their own inputs, with short computation times?
Thank you for any suggestions.
Related
I heard the terms Data Driven and Event Driven model from different folks in past. I did google but these terms are still vague to me as both
of them looks similar to me
Data driven programming is a programming model where the data itself controls the flow of the program ( not the program logic) where in case of Event driven programming ,
it is the event not the data itself controls the flow of the program.
Per mine understanding event is also the data . For example in employee based web application - If user clicks the create employee button, here event is create employee(which is also kind of data only) and data is employee related information.
Now at server first it will be event which will decide what will be flow of program and then data(employee related information) will also control the flow of execution like if permanent employee different method will be executed and if temporary it will be different
So is not every thing a data driven architecture ? If no what is the difference between them ? Any web based example will help
data itself controls the flow of the program ( not the program logic)
I guess you are not completely understand what is “flow” in this context. Flow is logic itself. For example, if you are executing some method that does A, then B, then C to it's arguments, logic would be “Apply A, B, C” and flow would be the same if actions A, B, C are extracted to separate methods. So, flow and logic are synonyms.
Data driven programming means that some general code exists. It does not contain any business logic, it does not control flow. It's just a tool to read and process data and output result. What controls flow and logic is data itself. So, if you want to change business logic (literally change result of your program), you change data, not code.
And your code is, well, it is a kind of pipeline that executes commands depending on input data. You can think of such code as of eval function in javascript.
In Event driven programming logic is controlled by events. And that means that data is only data, and all business rules are placed in code. Event would carry some data, and logic could be changed depending on event's data, but the difference here is where these changing logic rules are placed — in data or in code; and in case of EDP, the logic is in code.
Also, take a look at this question, some answers could shed some light on the subject.
The explanation above is very apt. To supplement the above answer, in Data Driven Architecture the business can feed in the logic directly in the data sheet thereby making it very easy to control the logic in the downstream components. Feeding is generally done using user friendly tools. Generally a product Master File is maintained which consists of the data variables and those are updated depending on the business requirement. It is so much easy for business to do this and a huge cost savings compared to event driven where every small change in business requirement resulted in huge cost to develop-test-deploy the piece of software.
I'm currently rebuilding a client's small mobile page, on my own dime, as a way to learn MVC and AngularJS, and in preparation for a much larger project for another client. The page I'm learning on is a single-page online ordering app for a pita restaurant. It allows you to choose from a list of pitas, then a second View allows you to customize your pita with various vegetables, cheeses, sauces, etc., followed by a third View, a form which allows you to submit your order.
My question is about the Model. I've built a system which takes the output from the database of menu items (pitas and toppings) and generates a JSON file, the Model, for Angular to parse and display for the user, but I'm curious where the user's selections will be stored.
Do I create another Model specifically for the user's selections or do I modify the original Model to hold the user's selections in addition to the original data?
This is somewhat complicated question in the sense that there are many variables. I am just going to layout how I would approach the decision:
Modifying the existing model being passed to the client means a few things.
First, it means that I won't have another model to deal with, but that the model is not focused on one thing (SRP violation). It is specifying a model in my domain as well as the relationship it has to another thing, the order. This leads to the object being in odd states in the sense it represents different things at different times/situations.
Second, I will have do do this to all my models that maybe connected to an order. Multiplying the above problem.
Creating a new model to represent an order mean another model to deal with (creating an API/service to manage it as well). The plus side is that I will be able to keep it focused on one thing: tracking an order. This means that my other models don't have to change and I know what the object truly represents at all times.
I obviously lean toward creating a new model because it is extendable/flexible and more clear to understand/support.
This doesn't have much to do with Ng or MVC or JSON. It has more to do with creating your models to most accurately and clearly represent your domain.
There maybe other consideration as well given specifics. Let me know by commenting.
I have a pretty good project task management system going in Microsoft Access, but one feature I'm still missing is some type of 'quick entry' like facility often found in many good productivity applications.
This is how it would work:
Scenario 1:
You're in another application, working on a few things, and you just remember something that needs to get done. You hit your predefined shortcut: CTRL + ALT + T (again, from outside Microsoft Access) and it brings up a small access form with a text box in to which you can type what needs to get done, e.g.
Inform key stakeholders of concerns regarding timeline
you hit return and that gets saved as a record in Microsoft Access instantly.
An alternative, and slightly more complex scenario...
Scenario 2:
As above, but you want to add further details besides the task name, such as the person you need to speak to, and a due date. The input in to the text box could look like this:
Inform #Sally of concerns regarding timeline >+3
Where '#' tells access to populate a field called 'Contact' with 'Sally' (unless it already exists) and '>+3' is interpreted by access to mean a due date 3 days from today.
How difficult are Scenario 1 and Scenario 2 to perform? What level of VBA/programming knowledge would be required?
Thanks,
I would say it requires a fair amount of confidence in VBA.
You need to register a global hot-key; that is, a keyboard-combination that can be captured from outside the Access application. It requires win-api calls. Here is some code.
You need to know where to place these calls. I believe you have to put them in a standard module, not in the form's class module. (I haven't double-checked this, it's late.)
You need to have a little understanding about what this code is doing. NEVER attempt to type this api-code - copy it from a reliable source, exactly as it is!! You don't need to fully understand the code, but you need to know how (and when) to call each function.
Once you've registered the hot-key then your VBA needs to bring your application to the front and display your form, and focus it. Reliably bringing the application to the front may also require api-calls.
Once your form is opened (and focused) you can have a button on it to parse the information in its textbox. However, if you are designing the form anyway, I would add checkboxes, comboboxes, etc., rather than trying to parse a complex sentence/ statement.
I'm working on a web application (Java EE backend) which contains a fairly complex input modal. This input modal allows the user to capture data, but it has a bunch of (JavaScript) restrictions, such as mandatory fields, fields only being available if a specific value is entered, etc.
I have to expose this functionality to external systems and allow them to submit this data to my server. These external systems can be both web or client based (but I can assume that the clients will have internet access). My first thought is to provide some kind of definition of the fields and stuff like mandatory to these systems through services, and have them render the input modal however they want. This has been met with resistance though, because the types of fields and restrictions will likely change quite a bit during the next few months of development. These external systems have different deployment timelines, and for this to work we'll have to firstly duplicate all the logic handling these restrictions across all systems, and secondly synchronize our deployments.
An alternative which has been proposed is to have the external systems call my modal through standard HTTP and render it either in an iframe or in an embedded rendered. This solves all of the previous complaints, but it leaves me feeling a little uneasy.
Are there any alternatives we are not thinking of? Maybe some kind of UI schema with existing render libraries for the different platforms? What are your thoughts on the second proposal, any major concerns or is this the "best" solution?
Edit: To clarify, I'll of course still perform backend validation regardless of the frontend decision, as I can't just trust the incoming data.
The constraints that you mention (mandatory fields etc.) really have nothing to do with the user interface. You are also right that it is not a good idea to have your backend render web content.
Your first proposal sounds like a good idea, here's how I would solve the issues you mentioned:
Do all the validation on the backend and send a model object to the client, representing the current state of the UI (field name, type, enabled/disabled, error message etc.).
Keep the client as dumb as possible. It should only be responsible for rendering the model on a window / webpage. Whenever a field is changed and it requires validation, submit the model to the backend for validation and get back a new model to be displayed. (You could optimize this by only returning the fields that changed.)
Doing it this way will keep your validation logic in one place (the backend) and the clients rarely need to be modified.
I have been faced with same issues in several previous projects. Based on this experience I can honestly say that server-side validation is the thing you will likely have to implement to avoid rubbish being committed from client side regardless if it comes from GUI or other third party system via API. You can choose one of available validation frameworks, I used Apache Commons Validator and think it is well, or you can implement your own one. On the other hand client side pre-validation, auto-completion and data look up are the solutions you should have to make human users happy. Do not consider about code duplication, just make your system right way from the business point of view.
This is often situation, but here is latest example:
Companies have various contact data (addresses, phone numbers, e-mails...) when they make job ad, they have checkboxes where they choose how they want to be contacted. It is basically descriptive data. User when reading an ad sees something like "You can apply by mail, in person...", except if it's "through web portal" or "by e-mail" because then appropriate buttons should appear. These options are stored in database, and client (owner of the site, not company making an ad) can change them (e.g. they can add "by telepathy" or whatever), yet if they tamper with "e-mail" and "web-portal" options, they screw their web site.
So how should I handle data where everything behaves same way except "this thing" that behaves this way, and "that thing" that behaves some other way, and data itself is live should be editable by client.
You've tagged your question as "language-agnostic", and not all languages cleanly support polymorphism, but that's the way I would approach this.
Each option has some type, and different types require different properties to be set. However, every type supports some sort of "render" method that can display the contact method as needed. Since the properties (phone number, or web address, etc.) are type-specific, you can validate the administrator's input when creating these "objects", to make sure that the necessary data is provided and valid. Since you implement the render method, rather than spitting out HTML provided by a user, you can ensure that the rendered page is correct. It's less flexible, but safer and more user friendly.
In the database, you can have one sparsely populated table that holds data for all types of contacts, or a "parent" table with common properties and sub-tables with type-specific properties. It depends on how many types you have and how different they are. In either case, you would have some sort of type indicator, so that you know the type of object to which the data should be be bound.
First of all, think twice do you really need it. Reason is simple. You are supposed to serve specific need and input data is a mean to provide that service. If data does not fit with existing service then what is its value and who are consumer of that specific information?
There are two possible answers: You are expanding your client base or you need to change existing service because of change of demand. In both cases you need to star from development of business model. If you describe what service you need and what information it should provide you will avoid much of specific data and come with clear requirements easy to implement in software.
I'd recommend the resolution pattern for this, based on the mention of a database. The link above describes it, but it's actually a lot simpler than it sounds. You write a database query that returns all the possible options (for example, you read the standard options and the customized options together using perhaps a UNION or a JOIN depending on your schema) - the COALESCE SQL keyword is then useful to find the first 'resolution' of the option value that isn't NULL.
Well, if all it is is that you have two options that are special, and then anything else is dealt with in the same way, then store your options as strings, and if either of the two special ones appears in that list, then show the appropriate stuff for that special item.
Just check your list of items for the two special ones. Nothing fancy.
By writing a very simple Rules Engine. You can use an out-of-the box implementation, or you can roll your own. Since your case seems so simple, I tend to roll my own, because it means less dependencies (YMMV).