Best practices for creating modular Web applications
- 1. Best practices FOR CREATING MODULAR WEB APPLICATIONS Iliyan Peychev HERE GmbH @ipeychev
- 2. CHALLENGES
- 3. CHALLENGES handling the Events Subscribing and unsubscribing to events Manipulating the dom Manually? Virtual DOM? Re-DOM? UNIT TESTS Mock everything? Staying as close to the reality as possible? maintaining the state State might be spread among different services or components
- 4. CHALLENGES OPTIMIZE APPLICATION How to achieve maximum performance? Rendering on the server too? Integration and end2end tests How do we keep them in sync with the code? CONTINUOUS DEPLOYMENT AND DELIVERY How easy is to make releases? How do we keep the documentation in sync? MAKING CHANGES TO THE SYSTEM How to prevent the “Software rot”?
- 5. There is no silver bullet Some of these challenges are technical, others aren’t (Technical challenges are easier to solve)
- 6. FRAMEWORKS Someone tells you how to write an application and gives you the tools for writing it
- 7. FRAMEWORKS and libraries 2006 2010backbone Model–view–presenter (MVP) application design paradigm YUI Powerful and rich, deprecated now jQuery Shaped the model for writing applications for years 2006
- 8. 2011 2013 2010 react Revolutionized the way Web applications were built ember Model–view–viewmodel (MVVM) pattern angular 1 Complete and rich, but complex and hard for maintenance and support FRAMEWORKS and libraries
- 9. 2017 2016angular 2 Complete and rich, better than Angular1 FRAMEWORKS and libraries ?
- 10. FUNDAMENTALS OF DESIGNING YOUR APPLICATION ARCHITECTURE COMPONENTS AND MODULES
- 11. WHAT IS A MODULE?
- 12. MODULE A “module” is a piece of functionality, which could be plugged to the application, replaced if needed and possibly reused a piece of functionality A module consists from one or more components One component should stay in one module
- 13. LET’S TAKE A LOOK AT THE REAL WORLD COMPONENTS AND MODULES
- 15. Components
- 16. Modules
- 17. Modules
- 23. Apply the same model to your applications (This is where things go wrong usually)
- 25. features as modules Separate the features of the application in modules One module may consist from multiple components The feature should be tested individually Then included to the application
- 26. COMPONENTS Prefer to create components, which only render data Create a few components to maintain the state They will provide data to the rendering components When testing, mock the external dependencies
- 27. Avoid framework dependencies when possible Try to make your classes framework agnostic Then “glue” them to you framework of choice
- 28. maintaining the state Maintaining the state properly is the key to keep the whole application maintainable Use Flux pattern and some implementation like Redux, MobX, or write your own
- 29. Do not follow blindly documentation/examples
- 30.
- 31. Test each component separately component 1 Module 2 Component 2 Component 3 Module 1 Component 4 } }
- 32. Then test the whole system component 1 Module 2 Component 2 Component 3 Module 1 Component 4
- 33. pack the module and distribute It might be NPM or any other module system
- 34. SHARE CODE Design the system with the idea to share code with other people
- 35. Module systems in JavaScript world
- 36. ES2015 Commonjs module systems amd Made popular by Node, in 2013 they said its dead Standard, not implemented in the browsers yet, but used widely with transpilers Originally split from CommonJS, the difference is the async loading
- 37. ES2015 features Re-exporting Export an imported module cyclic dependencies better handled than in CommonJS single default export export function circle(x, y) {} multiple named exports export const sqrt = Math.sqrt;
- 38. CREATING MODULAR Web applications IN PRACTICE
- 39. Could be part of an Indoor Positioning System Let’s create an application for monitoring iBeacons in range
- 40. PARTS OF AN indoor positioning system Venue maps Indoor Radio Mapping tool Detecting and monitoring Wi-Fi and Beacons Positioning API Location services/ End user applications
- 41. iBeacons Location Services Indoor detect send Enrich Anchor Services
- 42. Monitoring beacons 1 2 3 4 5 6 1 2 3 4 5 6
- 43. Architecture Main parts of the system Mobile application Mobile application created with ReactNative Web Application Web application, created with React Storage Data storage Server NodeJS server to serve the Web application
- 44. Which parts could be reused?
- 45. The Communication with the server Isolate it in a module It could be implemented using WebSockets, WeDeploy, etc. Location Services Indoor Location Services Indoor
- 46. Detecting the beacons on iOS and android Isolate the logic in modules with same API and expose it to React Native 1 2 3 4 5 6 1 2 3 4 5 6
- 47. rendering the beacons on the screen Isolate the logic in a module 1 2 3 4 5 6 1 2 3 4 5 6
- 48. More things to considerMake the Web application isomorphic Replacing the communication part on the fly
- 49. DEMO