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A Comprehensive Introduction To Apple’s Human Interface Guidelines

Overview

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Human Interface Guidelines suggest how interface components should look and how users will interact with them. There are as many ideas about interface design as there are proponents of any particular library or API. 

All interface designs share a similar goal, which is to create a unified user experience across the environment. To accomplish that, the guidelines help make their design’s interface intuitive, consistent, and learnable, both for the OS for its applications and tools. All interface elements and their guidelines should be included in an interface design document with usage examples, when practical. For example, buttons, checkboxes, dialog boxes, application views, buttons, bars, etc.

In Hamid Mahmood’s Lightning Talk session, we will breaking down the following topics:

  • Overview
  • Human Interface Guidelines
  • Customer Impact
  • Live Demonstration
  • Closing Thoughts
  • Additional Resources

Human Interface Guidelines

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Apple was one of the first companies to use “look and feel” in their literature when referencing the MacOS interface in the 1980s. As technology advanced, ideas on interface design also advanced.

Today, Apple has “Human Interface Guidelines” that establish how an application should look and feel to users on all of its platforms.

Apple’s HIG is an extensive document covering all aspects of application look and feel across the entire Apple ecosystem. There is a platform-specific HIG for each Apple OS environment: 

  • macOS for MacBooks
  • iOS for iPhone/iPad
  • watchOS for Apple Watches
  • tvOS for Apple TV

Apple’s HIG is organized by platform and technologies. Each platform is subdivided into sections. For iOS, for example, the sections cover architecture, user interaction, system capabilities, icons and images, bars, views, controls, and extensions.

From the iOS section topics, it’s evident that Apple is invested in ensuring that applications on their platform have that certain Apple “look” and that those applications function in a consistent manner. 

Consistency is an important factor in user uptake of new applications. When UI elements function similarly, it’s easier for users to transfer their operational knowledge between applications. 

Using the HIG helps maintain the quality of applications by guiding UI decisions to support the application’s operation. Following the HIG will improve engineering and design decisions by helping programmers anticipate what most users will expect from an application’s interface.

It’s important to remember that the HIG does not dictate how an application operates, it describes the user/application interaction through visual cues, controls, and application feedback.

Customer Impact

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When followed, the Human Interface Guidelines ensure that the components of an application’s UI are understandable to the average Apple user through familiarity with the OS and with other applications.

Maintaining a consistent interface helps create an application interface that is more rapidly accepted and gives users an increased feeling of being in control, which creates a positive user experience. A side benefit is that an application will complete the App Store approval process in a more timely manner because the UI and its controls appear and operate in the manner expected by the reviewers.

Live Demonstrations

Hamid Mahmood has crafted an intuitive walkthrough demonstration of the advantages of application coding within Apple’s Human Interface Guidelines:

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Be sure to follow Hamid’s entire Lightning Talk to follow along with these steps in real time.

Closing Thoughts

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Apps in this era of phones, laptops, tablets are not restricted to one device. Nor are users.

Therefore, it becomes imperative to adhere to some consistent UI guidelines to ensure a seamless experience and broader adoption by users. The cut-throat competition between iOS and Android has been good for both, making them more polished, more feature-packed and technologically potent. The best design services know how crucial it is to keep these guidelines in mind when designing interfaces on iOS and Android.

Happy coding!

To learn more about the implementation of Apple’s Human Interface Guidelines and to experience Hamid Mahmood’s full Lightning Talk session, watch here. 

Additional Resources

A Comprehensive Overview Of Apache Kafka

Overview

Apache Kafka is an open-source, distributed event-streaming platform, or message queuing system. Kafka provides real-time data analysis that runs on servers and clients, either locally or in the cloud, on Linux, Windows, or Mac platforms. Kafka’s messages are persisted on disk and replicated within the cluster to prevent data loss.

Some typical Kafka use cases are stream processing, log aggregation, data ingestion to Spark or Hadoop, error recovery, etc.

In Kyle Pollack’s Lightning Talk session, we will breaking down the following topics:

  • Overview
  • Basic Architecture
  • Benefits
  • Advantages Of Apache Kafka
  • Use Cases For Kafka
  • Closing Thoughts

Basic Architecture

There are four main components:

  • The Producer – The client apps that write their Events, or Topics, to the Kafka queue
  • The Topic – Topics are the Events that Kafka stores. They are multi-producer, multi-subscriber (Consumer), decoupled, and can have any number of subscribers or none at all
  • The Broker – Each Broker is a Kafka server that organizes and sequentially stores incoming Events by Topic and stores them on disk in Segmented Partitions
  • Consumer – The apps that subscribe to Kafka Topics

A Kafka cluster is made of one or more servers, called Brokers. Topics live in one or more Partitions on one or more Brokers. 

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As Producers write events to the Topic queues, the Brokers store the message in Segments within their Partitions according to Topic ID. Kafka always writes Event messages into any Partition configured for that Topic ID, on any Broker. Because the save is spread across all Brokers that service that Topic ID and the data is written non-sequentially into Segments within those Partitions, there is no single Broker or Partition that contains the full, sequential list of Events for that Topic. Each Partition only holds a subset of Event records in its Segments.

Kafka Producers

Producers are client applications writing Topics to the Kafka Cluster. 

Kafka Brokers

Brokers receive event streams from Producers and store them sequentially by Topic ID in one or more Partitions across one or more Brokers. Each Broker can handle many Partitions in its storage. All received messages are stored with an Offset ID.

For example, when receiving three events on a given Broker having three partitions, the Broker could store those Events to Partitions in this order 2, 1, and 3, while another Broker in the cluster could store them to 3, 2, and1. Because the writes to Partitions within Brokers are ad hoc, the individual Segments in any one Partition do not contain a sequential string of events. However, on retrieval, Kafka provides those records in their correct order by using their Broker-assigned Offset ID. 

Additionally, you can configure the Event retention as suitable for the application.

The Topic

Kafka organizes events by Topic and may store a Topic in multiple Partitions on multiple Brokers. This provides reliability and also enhances performance by avoiding the I/O bottlenecks that using a single Broker might entail, by spreading the store action across multiple computers.Topics are assigned Topic IDs.

Kafka Consumers

Consumers are apps that read Topic information from Kafka queues. Consumers automatically retrieve new messages as they arrive in the queue.

Benefits

  • I/O Performance – Non-sequentially writing Event records to multiple Brokers/Partitions avoids I/O bottlenecks that could occur if they were written sequentially into a single Partition.
  • Scalability – Kafka scales horizontally by increasing the number of Brokers in the cluster.
  • Data Redundancy – You can configure Kafka to write each event to multiple brokers.
  • High-Concurrency, low-latency, high-throughput
  • Fault-Tolerant
  • Message Broker Capabilities
  • Batch Handling Capability (providing ETL-like functionality)
  • Persistent by default
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Advantages Of Apache Kafka

Real-time data analysis provides faster insights into your data allowing faster response times. For example, to make predictions about what should be stocked, promoted, or pulled from the shelves, based on the most up-to-date information possible.

Even on very large systems, Kafka operates very quickly. You can stream all data in real time to make decisions based on current information, rather than waiting until the data has been obtained, aggregated, and analyzed, which is the case for many companies with large datasets.

Kafka is written in Java, so it is easier to learn.

Use Cases For Kafka

Kafka is used for: 

  • Stream processing
  • Website activity tracking
  • Metrics collection and monitoring
  • Log aggregation
  • Real-time analytics
  • Common Extensibility Platform support (CEP)
  • Ingesting data into Spark
  • Ingesting data into Hadoop
  • Command Query Responsibility Segregation support (CQRS)
  • Replay messages
  • Error recovery
  • Guaranteed distributed commit log for in-memory computing (microservices)
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Closing Thoughts

Apache Kafka is a distributed streaming platform capable of handling trillions of events a day. Kafka provides low-latency, high-throughput, fault-tolerant publish and subscribe pipelines and is able to process streams of events.

Happy coding! To learn more about the implementation of Apache Kafka and to experience Kyle Pollack’s full Lightning Talk session, watch here.

Configuration Automation Tools: Orchestrating Successful Deployment

Overview

In the modern technology field, buzz words come and go. One day databases are being discussed as the new best thing in the world of Agile Development only for the next, to recenter the importance of programming languages, frameworks, and methodologies.

But, one unchanging aspect of this lifecycle are the people who are an irreplaceable part of the creation, demise, and popularity of any given technology. This modern day world calls for close to perfection execution, of which individuals cannot always account for.

How does this call for flawless mechanisms affect the developers and creators, when called to building perfect products? 

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Automation is the technology by which a process or procedure is performed with minimal human interference through the use of technological or mechanical devices. It is the technique of making a process or a system operate automatically. Automation crosses all functions within almost every industry from installation, maintenance, manufacturing, marketing, sales, medicine, design, procurement, management, etc. Automation has revolutionized those areas in which it has been introduced, and there is scarcely an aspect of modern life that has been unaffected by it.

Automation provides a number of high-level advantages to every aspect of practice, making it an important process to have a working knowledge of:

  • Overview
  • Removing Human Error
  • Steps To Deploy
  • No Hidden Knowledge
  • Popular Implementation Technology Options
  • Closing Thoughts

Removing Human Error

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Automation, automation, more automation – and of course throw in some orchestration deployment and configuration management. Leaving the buzz words behind the “new technology frontier”, is removing human error. This translates to removing the dependencies of tribal knowledge when it pertains to application and system administration job duties.

Those job duties are performed in a repetitive fashion. The job duties are usually consolidated into various custom scripts, leaving a lot of those scripted actions with the ability to be boxed up and reused over and over again.

Steps To Deployment

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The primary cornerstones to prepping an automation deployment for an individual server, follow a near identical framework:

  1. Download and Install the various languages and/or framework libraries the application usages
  2. Download, Install, and Configure the Web server that the application will use
  3. Download, Install, and Configure the Database that the application will use
  4. Test to see if all the steps are installed and configured correctly

Running application tests ensure that the deployment is running as expected. Testing is crucial to the successful run of the deployment.

For example, something simplistic but highly catastrophic is the possibility of a typo. Consider the case of the following code:

  • cd /var/ect/ansible; rm -rf *

but instead a developer forgot the cd execute command and only ran

  • rm -rf /

In this case, the whole drive is at risk to be erased – which can and will make or break a product.

Taking time to ensure the correct command executions, can determine the overall success of a system.

No Hidden Knowledge

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Looking back on the steps to deploy an application to an environment, there are inevitably a number of small intermediary steps involved. A leader’s priority should be the revelation of each one of these unique sub-categories and effectively bringing all engineers around them up to speed on the associated best practices.

The information should be a source of truth maintained in a repository database, that is easy and intuitive to leverage

Popular Implementation Technology Options

What does a source of truth entail? Can one not skip the documentation of information and go straight into the execution of the steps onto a given system? Or create scripts to reconfigure the application if there was ever a need to? Those questions have been proposed several times and solutions have been formulated several times into the form of extensive and comprehensive build tools/frameworks.

These tools are used throughout the industry to solve the problem of orchestrated development, configuration automation, and management. 

Furthermore, DevOps tools such as: Puppet, Chef, and Ansible are well matured automation/orchestration tools. Each tool will provide enough architecture flexibility to virtually handle any use case presented.

Puppet

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Puppet was the first widely used Configuration Automation and Orchestration software dating back to its initial release in 2005. Puppet uses the Master and Slave paradigm to control X amount of machines. The Ruby language is the script language say, for executing commands in a destination environment. 

The “Puppet Agents” (Slave) are modularized distinct components to be deployed to a server. This can be used for the creation of the server (ie. web server, database, application) in its destination environment. The “Puppet Enterprise” (Master) is comprised of all the inner workings to manage, secure, and organize agents.

Puppet Documentation

Chef

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Chef is somewhat similar to Puppet. The core language used within Chef’s abstract module components is Ruby. Chef has several layers of management for individual infrastructure automation needs. The Chef workstation is the primary area for managing the various Chef components. The Chef components consist of “cookbooks”, “recipes”, and “nodes”.

“Recipes” are collections of configurations for a given system, virtual, bare metal, or cloud environment. Chef calls those different environments “nodes”. “Cookbooks” contains “recipes” and other configurations for application deployment and control mechanisms for the different Chef clients.

Chef Documentation

Ansible

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Ansible is the newest mainstream automation/configuration management tool on the market. Therefore, Ansible uses more modern programming languages and configurations concepts and tools. Python is the programming language used in this framework. One of the modern and fastest up-and-coming template languages is YAML. YAML is programming language agnostic and is a subset of the ever so popular JSON. YAML is used within Ansible to describe an Ansible Playbook. 

Ansible Playbook contains the steps that need to be executed on a given system. Once the Ansible Playbook is intact, configuration or further manipulation of the host can be executed through Ansible API – which is implemented in Python. There are several other components within Ansible technology such as modules, plugins, and inventory. 

Ansible Documentation

Closing Thoughts

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After covering a couple of the Configuration Automation and Development tools on the market, one can see a vast amount of flexibility available in eliminating those repeatable steps from human error. This software’s framework promotes reusable software within an organization – which is the most viable. The ability to scale an application development environment and environmental infrastructure is critical. 

The learning curve may be deeper than using plain bash scripts, but the structure and integrity of using a proven tool and ease of maintenance outweigh the learning curve.

Progressive Web Applications: The Best Of Web And Native

Overview

The web is an incredible platform. Its mix of ubiquity across devices and operating systems, its user-centered security model, and the fact that neither its specification nor its implementation are controlled by a single company makes the web a unique platform to develop software on. Combined with its inherent linkability, it’s possible to search it and share what you’ve found with anyone, anywhere. 

Web applications can reach anyone, anywhere, on any device with a single codebase.

Progressive Web Apps (PWAs) provide access to open web technologies, to provide cross-platform interoperability. PWAs provide users with an app-like experience that’s customized for their devices.

PWAs are websites that are progressively enhanced to function like installed, native apps on supporting platforms, while functioning like regular websites on other browsers.

In Aleks Rokhkind’s Lightning Talk session, we will breaking down the following topics:

  • Overview
  • App User Expectations
  • PWAs
  • Service Workers
  • Live Demonstration
  • Closing Thoughts

App User Expectations

Users expect to have an incredibly intuitive and smooth experience while interacting with both web-based and native mobile applications. However, on mobile devices, users often prefer interacting with the same content via the native app in real time, rather than an external browser. As a result, content providers are forced to maintain multiple codebases that need to simultaneously target different platforms in order to meet these expectations. 

PWAs

Progressive Web Applications work to address this cross-device challenge. In short, a Progress Web Application, or a PWA, is a website that has a near identical feel to a native application on a mobile device. 

A PWA looks to combine the direct advantages of both the web, as well as implementing the ability to intuitively work offline per a native application. 

As a website, a PWA touts a few advantages over native apps:

  • Discoverability – can be easily discovered in online search engines and implements SEO recommendations 
  • Linkability – can be viewed, installed, and shared from a URL, effectively bypassing an app store

As an application, PWAs allow for implementations that are quite similar to native apps:

  • Installability – users can instantly open the app, by tapping an icon on the device’s home screen, effectively allowing it to look and feel more like a native app
  • Network Independence – provides an offline experience
  • Re-Engageability – background sync, providing user push notifications
  • Access To Device Hardware – camera, microphone, motion sensors, geolocation, etc. 

In order to meet a plethora of different needs, a PWA is not a singular technology but instead an amalgamation of a number of intersecting hardwares:

  • Service Worker – a background script running tasks for the main application
  • HTTPS – allowing only secure connections
  • Manifest File – a JSON file with metadata that helps to install said PWA on a device, similar to native application files

Service Worker

A service worker is a proxy object that sits between a web application and the overall network. 

A service worker can perform a number of tasks and capabilities, that include but are not limited to: 

  • Intercepting, modifying, and serving the network requests and responses of the application. For example, when a device is offline, the service worker can serve up a previously cached response in order to provide a decent offline experience
  • Caching both the device’s static assets (stylesheets, scripts, icons, HTML, etc.) and dynamic data
  • Handling push notifications as well as background sync, even when the application is not being actively used
  • Running in threads separate from the main application, in order to cut down on slower run times

Live Demonstration

You’ve unpacked quite a few PWA principles – think you’re up to trying your hand at some practical application exercises?

Aleks Rokhkind has created an individual testing space just for you!

To rise to the challenge and apply what you’ve learned to the following application exercise, click here. 

Closing Thoughts

At their heart, Progressive Web Apps are just web applications. Using progressive enhancement, new capabilities are enabled in modern browsers. Using service workers and a web app manifest, a web application becomes reliable and installable. 

Progressive Web Apps provide a unique opportunity to deliver a web experience that users will love. Using the latest web features to bring enhanced capabilities and reliability, Progressive Web Apps allow a build to be installed by anyone, anywhere, on any device with a single codebase.

Happy coding!

To learn more about the implementation of Progressive Web Applications and to experience Aleks Rokhkind’s full Lightning Talk session, watch here.

A Comprehensive Guide To Java’s New HTTP Client

Overview 

The Hypertext Transfer Protocol (HTTP) is the foundation of the World Wide Web, and is used to load web pages using hypertext links. HTTP is an application layer protocol designed to transfer information between networked devices and runs on top of other layers of the network protocol stack. A typical flow over HTTP involves a client machine making a message request to a server, which then sends a response message.

Java is a general-purpose, class-based, object-oriented programming language designed for having lesser implementation dependencies. It is a computing platform for application development. Java is fast, secure, and reliable, therefore, it  is widely used by everyone from the newest to most advanced web developers. 

In Daniel Fuentes’ Lightning Talk session, we will breaking down the following topics:

  • What Is HTTP?
  • Improvements In HTTP 2.0
  • How HTTP 2.0 Impacts Java
  • Live Demonstrations
  • Closing Thoughts

The new HTTP 2.0 Client was released in Java 11. This new client is used to request HTTP resources over the network. It supports HTTP/1.1 and HTTP/2.0, both synchronous and asynchronous programming models, handles request and response bodies as well as reactive-streams, and follows the familiar builder pattern.

What Is HTTP?

HTTP is an application layer protocol designed to transfer information between networked devices. HTTP runs on top of other layers of the network protocol stack. 

HTTP is a protocol for fetching resources such as HTML documents. It is the foundation of any data exchange on the Web and it is a client-server protocol, which means requests are initiated by the recipient, usually the Web browser. A complete document is reconstructed from the different sub-documents fetched, for instance, text, layout description, images, videos, scripts, and more.

Clients and servers communicate by exchanging individual messages (as opposed to a stream of data). The messages sent by the client, usually a Web browser, are called requests and the messages sent by the server as an answer are called responses.

The typical flow over HTTP involves a client machine making a request to a server, which then sends a response message. 

HTTP was invented alongside HTML to load web pages using links (hypertext). It was a part of the first interactive, text-based web browser: the original World Wide Web. Today, the protocol remains one of the primary means of using the Internet.

Improvements In HTTP 2.0

HTTP 2.0 is based on streams and binary frames, in comparison to the text-only request models of its previous iteration. Unlike text-only interfaces, streams can be multiplexed asynchronously over one TCP (Transmission Control Protocol) connection. Comparatively, HTTP 2.0 reduces latency, therefore enhancing its performance. 

How HTTP 2.0 Impacts Java

Java was commonly built upon the HttpURLConnection class – which had an original launch in 1999 when HTTP 1.0 was still a fresh protocol. With a backbone built from outdated technology, it was never able to update properly in response to the rapidly changing nature of web protocols. 

Its steady incompatibility and lack of ease in use, led developers to opt out of Java’s direct class and instead employ third party solutions (ie. Apache, Netty, Eclipse, Google, etc.).

With the new updated Java 11 developer toolkit, came a number of operational changes – but namely, the adoption of HTTP 2.0. In order to meet the demand of an environment consistently in motion, Java made these longevity changes:

  • Eliminating the need for 3rd party client dependencies
  • Building in a backwards compatibility with HTTP 1.0 for remaining servers that may have not yet made the switch to HTTP 2.0
  • Instating an asynchronous support network for multiple HTTP requests
  • Vastly improving performance with the addition of Header compression and Single Connections for multiple requests

Live Demonstrations

Daniel Fuentes has crafted an intuitive demonstration to help guide you through this new Java HTTP in practicum: 

Be sure to follow Daniel’s entire Lightning Talk to view this impressive demonstration in real time.

Closing Thoughts

All programs should always be designed with performance and the user experience in mind. The properties explored above are the primary stepping stones to exploring the basic components needed to test HTTP 2.0 in order to improve your application. Be sure to explore, have fun, and match up the components that work best for your project!

Happy coding!

To learn more about Java’s Updated HTTP Server as well as its influence in web development and to experience Daniel Fuentes’ full Lightning Talk session, watch here.