APIs are now essential components of mobile applications and serve many decent purposes, so trends are rising to create custom RESTful APIs for the unique and innovative purposes. In due course, top mobile app developers try to know and learn API development.
Suppose your seat in a big Pub and looking for the best vine, it may be Whisky, Rum, Vodka, and so on. A waiter approaches your table and asks for the order, you place the order whatever you like to drink today. The waiter goes to a storage room or service counter where the service request is taken, deliver the wine bottles or glasses of vines and prepare the bills accordingly.
It is a waiter who used to connect seated customers with service counter and accomplishes critical business needs.
Understanding Needs of API
Now, we shift our eyes from common-man’s perspectives to a software engineer’s perspectives.
We used to take services of GPS system where satellite data define the location of GPS enabled device and want to present to the device user. We know GPS data come into the format of geo-location coordinates that hardly anyone can understand. Therefore, we need to render world map that pinpoints the exact location of the user using those coordinates-data.
Google Map services are for this specific purpose, and we need to bring its interface on the device or the user. So, it could be possible? Let’s go to our previous example of a waiter in a pub.
Here, our waiter acts as an API or ‘Application Programming Interface,’ which connect a client device like a desktop PC or a mobile device to the web server of Google, Amazon, Facebook, Twitter, LinkedIn, and many in due course that provides APIs for their services.
Just like our waiter, API takes requests from the client devices and pass to the web servers or cloud servers for further processes. Once the processes are accomplished and results/products ready to serve the client-device, the same API brings those to the client device from the server and finish its job.
Up till this point, we have talked about external APIs provided by the third-party service providers that we used to integrate with our mobile applications and leverage their services whether for free of charge or something in exchange of the services.
Now, suppose you have a big mobile and web applications for internal and external usage, and you need to develop your API internally. You need to have a guide to building a useful, efficient, and cost-effective API for your internal use. To serve the same purpose, the current post is giving massive guidance as an outline for the aspirant mobile and web developers.
What is API?
Technically, API is a series of request messages (In the form of HTTP/s), which communicate protocols, routines, and various tools to build and run the software application. At present, two main types of API protocols used by developers.
- REST (Representational State Transfer)
- SOAP (Simple Object Access Protocol)
Advantages of REST APIs
It has observed that nearly 70% developers prefer REST over SOAP due to following advantages:
- It is easy to learn and use
- No expensive tools needed while interacting with servers
- Use small code/message formats to interact so fast and efficient.
- It requires no extensive processes so fast to execute
- It supports the modern web technologies.
- Its popular request formats are XML-RPC, REST, and SOAP while some use PHP and JSON too.
Constraints of REST APIs
REST API becomes RESTful only when it follows the following constraints. Each constraint adds some useful properties to the system. For instance,
- Uniform Interface: Makes the system simple, usable, evolving, and dependable.
- Client Server: Makes the system simple, evolving, and scalable.
- Stateless: Makes the system simple, maintainable, evolving, and dependable.
- Cacheable: Makes the system scalable and performing.
- Microservices: Makes the system flexible, scalable, maintainable, performing, and dependable.
- Code-on-Demand: Makes the system evolving.
Creating RESTful APIs for Mobile Applications
Today APIs consider as a product rather than a bundle of code, and it has a targeted audience too- Developers. Therefore, companies create developer-friendly APIs with standard architecture, security concerns, and treat as a software product with own Software Development Lifecycle (SDLC) for design, development, testing, and management purposes.What Sets Mobile APIs Apart from Web APIs
However, APIs for mobile apps are somewhat different from the websites or web applications due to mobile constraints. Therefore, building RESTful APIs for mobile app demands the following care:
Today most of the web and mobile applications prefer HTTPs instead of less secure classic HTTP. So, using HTTPs provide more secure and trusted environment when the latest encryption technologies implemented.
Shift Loads to Server
Mobile client-devices are thin in terms of processing, power, and storage capacities. Let server does the heavy lifting, so program remote API to shift the burden from thin mobile client to heavy machines on a server.
Select & Configure API Server Properly
The mobile app ecosystem is highly sensitive to issues with your app, and you may get negative ratings or reviews in app stores instantly when an issue arises due to faults on server-side. Therefore, take care of sever selection and configuration according to technical requirements of your API.
When you publish your app in the real world, it runs in wild and users may update it regularly or not. Therefore, you need to manage previous versions and their API requests on the server too. Thus, you have to consolidate the server and handle various requests from a variety of API & app versions.
Leverage Push Notifications
App notification is a highly efficient and effective tool for various purposes that lead to app success, and you can go for third-party tools to manage them in your app.
Managing Offline Activities of App
Most of the apps today come with somewhat offline activities, and you have to manage API activities accordingly. In due course, timestamp provisions for API calls are great and work effectively even when a user uses multiple devices for the same app functions.
Considerations for RESTful API Development for Mobile Applications
Before planning the development of RESTful API development for your mobile app, you should address following common concerns to make it success legend.
Architecture for RESTful API Development
For API development, we have to plan three different types of backend environments.#1-Development Environment
Developers make frequent changes and roll out. Databases have artificial data generated by developers through scripts. Frequent testing of API is going on with each change made by developers.#2-Staging Environment
Here trying to simulate the production environment is going on but within managed ways to testing of real data becomes a possibility. The quasi-representative data cut the risks associated with API functionality and features and gives tests of API logic in a secure environment. Thus, you can find bottlenecks before occur in real-world /production environment.#3-Production Environment
It is real-world environment where your app is published, and in the hands of actual end-users, you have targeted. So, you will have to bear the sweet or sour fruits for each mistake you have left during development and staging environment and had only one option to correct it all, and it is releasing updates.
Selection of Database and Data Storage
Database selection makes sense when you are looking for performance parameters related to data, data transfers, and data security. You have three options to make a selection of database type for your RESTful API development and running in production environment. Those are:#1: SQL or Relational Database in the form of tables
For instance, MySQL and MariaDB, which are established, stable, and reliable. Those have extensive libraries, frameworks, and tools. Data are the rigid type, structured, and defined so less prone to bugs and various security as well as performance issues. Of course, managing SQL databases demands expertise and tough job.#2: NoSQL or Non-Relational Database in the form of documents
For instance, MongoDB, which are table-less, non-rational, and without any schema. NoSQL databases are easy to scale, ramp up, iterate, and manage.#3: Mix types of database
For instance, PostgreSQL, which are flexible to mix both types of databases described above. Therefore, their popularity is on the rise and giving more features and tools for innovative functions.
Hosting API Server
For storage purposes, hiring web server with VPS or dedicated packages is a good idea but leveraging cloud hosting offerings is an excellent choice to make. Cloud servers are highly secure, best performing, and cost-effective way to store your app and API data.
For API hosting, you need to consider following things:
- Room for horizontal and vertical scaling
- Scope for three different API backend environments-development, staging, and production, as well as possibilities of easy migration from one to another
- Facilities to recreate features and functionality
- Security aspects like data storage, backups, and data protection through the latest technologies and infrastructure
- Platform independent, so you can go for iOS app APIs, Android app APIs, and any OS platform based APIs
Aiding Tools in API Development
Communication is the key to collaboration, and today we have advanced communication channels as well as project management software to create synergy among the development as well as business teams. Today ‘Trello’ and ‘Pivotal Tracker’ are highly used tools among the developer community.
Versioning management through GitHub like the platform is an excellent idea to allow a big team to work on your big scale API development project. The next is testing frameworks to test the functionality and quality of your APIs, and the selection of testing frameworks depends on the programming technologies used in your RESTful API development.
Other useful tools are:
- ‘Postman’ is an excellent documentation tool, and you can use to document the entire development process including useful pieces of code and drawings for later references.
- Swagger- neutral language tool
- Apiary- built on top of API Blueprint
- Slate- supports markdown
Design API in RESTful Manner
I would like to give you some useful tips to design APIs in a RESTful manner.Tip No.1:
Try to use familiar architectural style to design APIs, such as
- Pragmatic REST
- Web Service
- Event Driven
Among these, Pragmatic REST is the right choice for mobile app API development. Event-driven architecture is useful in certain cases only.Tip No.2:
Use layering appropriately. For instance,
- The security layer is highly important to put it at the top.
- The next should be caching layer to enhance the API performance.
- Make representation layer developer-friendly.
- Use orchestration layer next to interface to combine data from different APIs.
Use URL parameter to handle filtering, sorting, pagination, and searching. In due course, you need to create your API endpoints carefully.Tip No.4:
Follow the rules for request and responses to communicate effectively within endpoints. Those rules for the request are:
- Don’t force client devices to send only selected fields but allow them to send full objects if they wish.
- Take care of content-type and try to accept headers in queries.
- Be consistent using CamelCase or snack_case and remember snack_case is legible though CamelCase is the norm.
- Avoid wrapping data with meaningless envelope.
These are some sweet & short guide to design and develop APIs for mobile applications. However, for details, you must come in contact with experienced and expert mobile app developers with flairs in APIs development.It is a team of SysBunny that knows how to achieve desired success in API development for mobile apps so that you can leverage their flairs on easy terms.