DeChat

Since we use the POD technology we are subject to its changes and bugs, wich can end up making the user lose information due to a bug unrelated to the app.

Unfortunately there is little we can do without interceding in Solid’s development.

Because we have to depend on Solid’s confusing interface it may lead to authentication problems due to the different authentication ways Solid has which can confuse an amateur user of Solid.

This point is easily supressed once the user gets used to interacting with solid, however, to ensure that it doesn’t cause problems, we’ve made our own interface where the user can choose its provider of PODs and then access.

As every application on SOLID, once the user has verified its identity, this application, if something goes wrong, can make undesired changes, corrupt the system or touch data that other application may be using, causing it to malfunction

As this is an inherent problem of the POD architecture it isn’t possible for us to solve this issue, at most we can try to limit the data that the application may try to touch in hopes that it doesn’t damage anything.

Related to the previous point, privacy is at risk as well. Since the POD’s data can be read by every application you use it with then your conversations can be read by every other app.

Unfortunately we couldn’t come up with a solution to this one, since using a key to encrypt the data wouldn’t work because the place where you save the key is also public to the other applications.

A notable deficiency is that, as SOLID is implemented right now, gathering information is not as fast as it would be desirable

No solution has been found as of now.

Another deficiency could be the small number of libraries of RDF, and their resistance to being used, making the code messy

With time other libraries will, probably, appear, and this deficiency will be solved.

If a user takes down its POD then it would leave any user that had a conversation with the first with only half the conversation.

It’s the other side of the decentralization, as information remains in each POD it makes sense that, since a POD is no longer there then the information isn’t either.

If a POD is temporarily inaccessible, due to a failure in the server or faulty connection, then users would only be able to see their part of the conversation with the faulty POD’s user

A downside of decentralization.

Since the communications are done via API REST they could be inercepted and modified as the POD doesn’t have a verification system

A current error of SOLID.

POD

It’s a personal online data stores hosted wherever the user desires, as long as it’s a SOLID server.

SOLID server

A server built on the Solid platform following SOLID specifications.

SOLID

Solid (derived from "social linked data") is a proposed set of conventions and tools for building decentralized social applications based on Linked Data principles. Solid is modular and extensible. It relies as much as possible on existing W3C standards and protocols.

ARQUISOFT

It refers to the organization made by the teachers of Software architecture to group together all the teams trying to make a SOLID chat.

Version control

It’s the management of changes to documents and code of the application by identifying changes with names and codes.

DeChat

It’s the shortened version of "Decentralized chat"

Linked Data

Linked Data is a method of publishing structured data so that it can be interlinked and become more useful through semantic queries.

Semantic Queries

Semantic queries are queries that enable the retrieval of both explicitly and implicitly derived information based on syntactic, semantic and structural information contained in data.

RDF

The RDF data model is similar to classical conceptual modeling approaches (such as entity-relationship or class diagrams). It is based on the idea of making statements about resources (in particular web resources) in expressions of the form subject-predicate-object. The subject denotes the resource, and the predicate denotes traits or aspects of the resource, and expresses a relationship between the subject and the object.

Decentralization

Decentralization is the process by which the activities of an application, particularly those regarding planning, decision making and data, are distributed or delegated away from a central, authoritative location or group.

Layered architecture

It’s an architecture that is organized into horizontal layers, each layer performing a specific role within the application (e.g., presentation logic or business logic).

MVC

Model View Controller (MVC) is a style of architecture that separates the data from an application (Model), the user interface (View) and the control logic (Controller) within 3 separate components.

Angular

It’s a TypeScript-based open-source web application framework led by the Angular Team at Google and by a community of individuals and corporations.

TypeScript

TypeScript is an open-source programming language developed and maintained by Microsoft and a superset of ECMAScript 6 (ES6), which is also backwards compatible with ECMAScript 5 (JavaScript).

Node

Node.js is an open-source, cross-platform JavaScript run-time environment that executes JavaScript code outside of a browser. Since TypeScript is backwards compatible with JavaScript, it also works with Node.

API

An API (application programming interface) is a set of subroutine definitions, communication protocols, and tools for building software.

REST

REST (Representational State Transfer) is a software architectural style that defines a set of constraints to be used for creating Web services. There is also the API Rest which is an API that implements the REST architecture.

Web Petition

It’s, in a client-server computing model (sort of what we are using), a request from the client side (the app) to the server (the POD).

Mock up

mockups are a way of designing user interfaces on paper or in computer images. A software mockup will thus look like the real thing, but will not do useful work beyond what the user sees.

Uri

A Uniform Resource Identifier (URI) is a string of characters that unambiguously identifies a particular resource.

Cross-cutting Concepts

They are rules, principles or other decisions, guidelines, processes that influence one or more elements of the architecture.

Principle of single responsibility

it’s a computer programming principle that states that every module, class, or function should have responsibility over a single part of the functionality provided by the software, and that responsibility should be entirely encapsulated by the class.

Open-closed principle

it’s a computer programming principle that states that classes should be open for extension but closed to modification.

Dependency inversion principle

it’s a computer programming principle that states that high-level modules should not depend on low-level modules, both should depend on abstractions (interfaces), an that abstractions should not depend on details. Details (classes) should depend on abstractions.

Bug

An error that can, and normally will, cause damage to your data.

Card

It’s the location inside the POD where the user’s information is stored.

Inbox

It’s the folder in the POD where everyone else can write but can’t read or modify; this is used for notifications.

Karma

It’s a tool which spawns a web server that executes source code against test code for each of the browsers connected.

Cucumber

It’s a tool used to make end-to-end tests; this kind of tests are used test the entire application in one go.

Selenium

It’s a portable framework for testing web applications. In our case we need it as a driver to use Cucumber.

Protractor

It’s an end-to-end test framework for Angular and AngularJS applications. Same as Selenium, we need it as a driver for Cucumber to work.

Testing

It’s a practice which consists on trying to run the application to confirm that it works when it has to work, and that it doesn’t when it shouldn’t.