Questions about problem solving and planning for a solution through software design.

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1
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3answers
103 views

Unit testing functions calling other tested functions [duplicate]

I have three functions: ValidateUsername(), which determines if a string is a valid username according to some rules SetUsername() which sets a string as a user's Username if it passes validation ...
3
votes
1answer
152 views

Providing views to an std::container

I want to maintain a buffer of 5 seconds of sensor data. The sensor data consists, among other things, of accelerometer readings in x,y,z dimensions, gyroscope readings in x,y,z dimension and ...
0
votes
0answers
60 views

php - design: database operations

I am working on a control-panel for a VoIP program and I've been working on it for a while. It started off as a small project that I just did because it was fun, but over time I added more and more ...
-2
votes
1answer
26 views

How to design task assignment system?

I want to design a system which is similar with stackoverflow review feature. That is to say: There are n tasks, which should assign to users (users count is unknown). At one time, one task should ...
0
votes
1answer
50 views

Efficient way to handle foreign keys

I am building a script that checks a large network of sites for invalid links. The idea is to flag links that continuously show as not available so that they can be cleaned by the administration team. ...
1
vote
3answers
99 views

Performing data operations that involve separate applications and data sources

I'm designing an enterprise application that produces output based on some input data from another application. In this case, I happen to have also built and thus do control the source application ...
0
votes
4answers
250 views

How can I avoid the use of strings?

I'm implementing a program where the user can 'create a musical scale' from a variety of notes (identified by their names), and the program will generate music from this scale. I want to implement a ...
11
votes
5answers
2k views

Software Manager who makes developers do Project Management

I'm a software developer working in an embedded systems company. We have a Project Manager, who takes care of the overall project schedule (including electrical, quality, software and manufacturing) ...
2
votes
1answer
69 views

An approach to multilingual db design

My boss is planning on a new db and wants to support multilingual data in this manner: LocalizedDescs (Guid / LanguageGuid being the primary key) Cluster Guid LanguageGuid Desc ProductCategories ...
2
votes
1answer
56 views

Access modifier of abstract class constructors

What access modifier should I use for my constructors in an abstract class, given that the class cannot be instantiated? It seems like the access modifier is superfluous and should be implicitly ...
0
votes
0answers
78 views

Should different projects that share a DB also share data access and other code?

I work on a product that consists of a a single database, and a couple of separate (but related) website projects. The main ones are: public facing site back-office site for our customers to use to ...
1
vote
2answers
42 views

Instantiating a set of Objects from information in File

Let’s say I have four classes A,B,C,D. Each of those classes contains a Tree object. This tree object needs to be built according to information stored in files f_A, f_B, f_C, f_D, for classes ...
0
votes
2answers
194 views

Cost estimation in software engineering

I was asked by my Boss to do a cost estimation for a specific iOS project. Well I have several years of development experience , but I never had to do a cost estimation. What I did so far: iOS I ...
1
vote
1answer
40 views

Synchronization of resource that has moved out of requests filter range

I have a RESTful API with corresponding clients. If a client request fetches a set of resources (Events) based on a filter, say events taking place between 2015-04-13 - 2015-04-19. If an event which ...
4
votes
1answer
63 views

Where to create a file in WPF/MVVM

I'm building a WPF/MVVM application that takes input from the user and generates an output document which it saves in a temporary folder and opens for display in the native application (e.g. MS Word). ...
2
votes
4answers
148 views

Rich object model in the context of a good REST API and of an existing rich object model on the server-side

First off, let's frame this question in the context of a good REST API and an existing rich object model on the server-side, as well as modern web architecture (MVC frameworks like angularjs). I'm ...
4
votes
3answers
442 views

When is an object of real world a (computational) object in OOP world?

In an OOP design phase strategy, Any physical/conceptual object of a system can be modeled(considered) as computational object in your OOP designed program based on below two conditions: First ...
1
vote
1answer
207 views

MongoDB Embedded vs Reference Private info

I have searched extensively for a similar Mongo schema design and can't find relevant examples. I have a store (with public info), each store has an account (with private account info). // store ...
1
vote
1answer
67 views

Design consideration on JSON schema for an API

I have an API endpoint that retrieve data from 3 SQL tables on the server-side. At the moment, I do a SELECT with joins, consolidate/reorganize the selected data based on a JSON schema, and then send ...
0
votes
0answers
20 views

Which document model to choose in different situations

I needed some custom document format and stumbled on this issue. DocBook does it this way <chapter> <title>Chapter 1</title> <para>Hello world!</para> ...
2
votes
2answers
525 views

Is there a better way to organize my module tests that avoids an explosion of new source files?

I've got a neat (so I thought) way of having each of my modules produce a unit-test executable if compiled with the -DTESTMODULE flag. This flag guards a main() function that can access all static ...
0
votes
0answers
31 views

Where to generate View?

I plan to build a CRM for small companies. It is supposed to be a single-page application. Now I am unsure where it is more efficient to convert the data to HTML. Should I rather do it on the server ...
0
votes
0answers
40 views

Good architecture with DI where low-level components can interact with another hierarchy details

What would be a good design for accessing low-level components attached to another parent? Assume each User has its own hierarchy and one low-level class wants to send a message to some low-level part ...
2
votes
0answers
79 views

Architecture design for Java servlet that triggers work (for sending push notifications)

I'm designing a push notification server (for pushing notification via APNS and Google servers) and have come up with the following design for a Java based web application server. I would really like ...
5
votes
7answers
3k views

Ways to have a history of changes of database entries

What are ways to allow the versioning of database entries (data)? Think of the content-managment-systems abilities to revert back changes of articles. What are their pros/cons?
0
votes
0answers
41 views

Best practices for creating a project utilities module? [migrated]

Does anyone know of any best practices around creating a utilities module or class specific to your project? I have a project I've been working on that has three different moving pieces, but we keep ...
2
votes
2answers
97 views

Design interface for WebService to access several MySQL databases

I am currently trying to design an interface for a WebService that can access several MySQL databases. There will be 4 operations available, Add(), Read(), Update() and Delete(). The WebService just ...
0
votes
0answers
38 views

Implementing peristent events using WCF-MSMQ

I am implementing a WCF-MSMQ based message queue that will follow the pub-sub model in which multiple publishers would publish an event and multiple subscriber would listen to it i.e a many to many ...
-3
votes
0answers
41 views

For Review: My UML Structure for a PHP PDF Invoice Module

I like to develope a simple PDF Invoice Module on PHP5. It s important for me to provide a good design and code structure. For that, I made the following UML: http://postimg.org/image/yzxandd0p/ The ...
1
vote
2answers
161 views

Is there a pattern to assist with working around or fixing violations of the Liskov Substitution Principle? [closed]

I've come across a rather large violation of the Liskov Substitution Principle in our codebase. There is an abstract class. Within it is an abstract method, implementers of which are expected to ...
2
votes
1answer
78 views

Best way to organise the software for microcontroller external peripheral drivers

Recently, I have begun designing and writing code for microcontrollers in order to get a deeper understanding of how they work. The first major project I have undertaken involves writing a driver for ...
0
votes
1answer
76 views

Flat files for events and alarms

So I'm working on a project that I was introduced to a year ago. One of the features of project involves alarming the users when certain events are triggered. There is also a log of these events. ...
15
votes
2answers
10k views

What alternatives are there to using HTML/CSS layouts for websites? [closed]

Is there any existing in-use, or even just conceptual attempts at creating a markup or programmatic expressions for designing the layouts of websites other than HTML/CSS? If there are others out ...
3
votes
2answers
216 views

IoC invalidation

I have a bunch of services that get registered as singletons by my IoC container on startup, all of these services have a constructor which takes in a connection string which is used by the underlying ...
2
votes
1answer
63 views

Reuse already fetched data for request

I have action that fetches user model from db to check access. Then I have method that in some cases requires same model. function checkAccess(req, res, next) { var data = ...
4
votes
1answer
165 views

OOP design for conditional event processing queue

This will be in C++11, but the object design should be rather agnostic. I have 3 interface classes, IEvent, ICondition, IRunnable. The main loop processes multiple kinds of IEvent, ranging from "an ...
2
votes
1answer
170 views

Events in WCF Service Architecture (Server Side)

Problem: Now, I have some events that will take place when the client submits a request to the server. These events will arise on the server and they will be subscribed by the services themselves ...
21
votes
9answers
3k views

What can go wrong if the Liskov substitution principle is violated?

I was following this highly voted question on possible violation of Liskov Substitution principle. I know what the Liskov Substitution principle is, but what is still not clear in my mind is what ...
0
votes
0answers
31 views

Defensive Programming - “Return” placement [duplicate]

Sometimes I see myself writing code in the following way: if(value == null) return null; //... I will have here as many defensive conditions (and returns) as I need //... Continue to execute method ...
37
votes
6answers
7k views

Hardcoding strings that will never change

So, in my efforts to write a program to conjugate verbs (algorithmically, not through a dataset) for French, I've come across a slight problem. The algorithm to conjugate the verbs is actually fairly ...
0
votes
0answers
23 views

Dealing with stale data / currency issues when lazy loading related entities

Imagine I have two associated domain entities with a one-to-many relationship. Here is an example with Customer and Order classes: public class Customer { public int ID { get; internal set; } ...
27
votes
10answers
6k views

What is good (neat) architecture in programming a simple website, e.g. a contact book?

When I build a simple website, e.g. a contact book where I can add, delete and update contacts, I create an index.php file where a user, if he's not logged in, is requested to enter a password and if ...
3
votes
1answer
87 views

Business concept design vs logical database design

Good day. I need help for a specific case. A little background: We have an existing app, it is like a PDF viewer, and you can draw freehand, highlight, add highlight with notes, add action items, etc. ...
6
votes
5answers
1k views

Why doesn't Haskell have a 'format' function for string interpolation?

I'm trying to use Shake and I stumbled upon the following problem: there's no easy and convenient way to interpolate a string. I know about Text.Printf — it's not what I'm looking for. The ...
1
vote
1answer
78 views

AngularJS Different Controller per Role?

I am creating an AngularJS app with a restful-back end. I have 4 types of users for which each component/page may have significantly differnt behavior. What is the best approach to implement this? Do ...
25
votes
12answers
2k views

How large is ok for a Class?

I’m a long time developer (I’m 49) but rather new to object oriented development. I’ve been reading about OO since Bertrand Meyer’s Eiffel, but have done really little OO programming. The point is ...
0
votes
2answers
64 views

What are some (best) practices of organizing configuration data for applications? [duplicate]

I am working on an application (in php) that needs some rules to evaluate the labelling of some data. Since these rules might change someday, I decided not to hardcode them, rather handle them as ...
0
votes
2answers
118 views

What kind of design diagram is this?

Here is a kata for the Bowling Game problem. Slide 9 (below) shows a design diagram. But its not obvious to me which box is a class and which is a property or method from the makeup of the boxes ...
3
votes
1answer
241 views

Domain Driven Design - designing Aggregate Roots

Imagine you're designing an application for organizing Workshops. Workshop itself is quite complicated - it acts as a state machine with multiple possible states and transitions between them. We're ...
1
vote
3answers
90 views

Dependency inversion without static methods?

It's clear that the dependency inversion principle and the use of interfaces makes software components less coupled and promotes maintainability. On the other hand, these principles make using static ...