Microservice Architecture with Reusable Components at JSFest

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1. Microservice Architecture with Reusable Components Mar 30, 2018
2. Slides JSFest bot
3. Nikita Galkin Love and Know: ▰ How to make developers and business happy ▰ Technical and process debt elimination Believe that: ▰ Any problem must be solved at the right level ▰ Software is easy. People are hard ▰ A problem should be highlighted, an idea should be "sold", a solution should be demonstrated Links: Site GitHub Twitter Facebook 3
4. 4
5. 5 “Wanna do something good, do it yourself” Jean-Baptiste Emanuel Zorg (Gary Oldman)
7. 7 “Almost all the successful microservice stories have started with a monolith that got too big and was broken up” from MonolithFirst Martin Fowler
8. 8
9. 9 “I picked Java because I felt the most people would be able to understand the code examples if they were written in Java. That was the case in 1997, but how about in 2017? … But I went for the alternative: JavaScript.” 27 March 2018
11. Components
12. Best Practices
13. Reusable Components
14. 14 Why?
15. 15 Don’t Repeat Yourself
16. 16 What?
17. 17 Scoped packages
18. Scoped packages 18 ▶ npm install @zorg/zf + @zorg/zf@1.0.5 added 1 package in 1.727s ▶ cat ~/.npmrc @zorg:registry=http://npm.zorg-weapon.com
19. 19
20. 20
21. First package 21 ▰ @your-scope/code-style ▰ Code Style and Violence by Anton Nemtsev
22. 22 What is not reusable component?
23. 23
24. “Small, autonomous services that work together. 24
25. Evolution
26. 26
27. 27 How?
28. 28 Robustness Engineered for engineers Useful Simple Examples included
29. npm i -g how-to-npm how-to-npm Or Free 1,5 hour-long video: How to Write an Open Source JavaScript Library
30. Git flow 30 How to convince the team?
31. 31 How to convince the manager?
32. “Wanna do something good, do it yourself” Zorg
33. “Wanna do something good, do it yourself” Zorg
34. “Don't use require(../../utils/logger), use npm packages” © Galkin Awesome Pair! But how reuse code... Microservices
35. 35 How to develop reusable components?
36. ▰ npx scripts ▻ eslint helper ▰ plop ▰ yeoman.io ▰ raml2html Code, spec, docs generators 36
37. Generators 37
38. Test Driven Development 38 FAIL PASS TDD REFACTORING “Repetition of a very short development cycle: requirements are turned into very specific test cases, then the software is improved to pass the new tests, only.” Kent Beck
39. Types or Documentation Driven Development 39 tsc Add JSDoc TDD ▰ choose typescript or JSDoc ▰ autocomplete for engineers ▰ always actual code documentation ▰ puppeteer source-code is awesome JSDoc example REFACTORING
40. /** * @typedef {Object} CoverageEntry * @property {string} url * @property {string} text * @property {!Array<!{start: number, end: number}>} ranges */
41. Theft Driven Development 41 STEAL ADOPT TDD SHARE
42. Reusable Components
43. I'll show you my package.json during speaker corner
44. 44 Where?
45. Source code storage CI for build and test Artifact storage
46. Git flow 46 Git flow
47. Git flow 47 Git flow
48. Github Flow
49. Monorepo with Lerna
50. Or one repo for one component?
51. Your DevOps Engineer: @#_$!
52. Your DevOps Engineer: @#_$!
53. 12factor.net
54. “II. Dependencies Explicitly declare and isolate dependencies 54
55. “III. Config Store config in the environment 55
56. “V. Build, release, run Strictly separate build and run stages 56
58. “VI. Processes Execute the app as one or more stateless processes 58
59. “XI. Logs Treat logs as event streams 59
60. stdout stderr
61. 61 How to develop microservices?
62. MonolithFirst
63. How your system works?
64. ECB is a variant of Model/View/Controller (MVC). It was published by Ivar Jacobson (Ericsson Co.) in the 80's with a focus on separating responsibilities of elements in Object Oriented Systems.
65. Boundary – objects that interface with system actors (e.g. a user or external service). Side effected. Boundary component should be reusable. EBC Pattern – Boundary 65
66. Boundary place for validation
67. ▰ Wrapper for Enterprise Bus ▰ File Storage wrapper (S3/Local FileSystem) ▰ JSON RPC with different transports Possible Boundaries Components 67
68. Control – objects that implement business logic. This code has the main value for business. This part of every microservice is unique. EBC Pattern – Control 68
69. Control – just control.
70. Entity – objects representing system data, often from the domain model. In our application we use an entity also for transforming data from one format to another. For example, from XML to JSON. Entity can be shared between applications as interfaces or components. EBC Pattern – Entity 70
71. Entity for data transform
72. microservices base application with: ▰ Base boundary class ▰ App class with start stop ▰ Default logger ▰ Hooks Basement 72
73. 1. Only Boundary provide services for the "other world". 2. Boundary can call only to Control. 3. Control can call anybody. 4. Entity can't call anybody (!), only be called. EBC Pattern 73
74. 74 Why does it matter?
75. Bootstrapping and Graceful shutdown
76. Interface Microservice { void start(); void stop(); } Microservice interface 76
77. Bootstrapping
78. 1. Attach uncaught exception hooks. 2. Log start of bootstrapping. 3. Verify configuration. 4. Init boundaries and controls. 5. Attach shutdown hooks. 6. Log finish of bootstrapping. Bootstrapping 78
79. Graceful Shutdown
80. For graceful shutdown application should: 1. Log start of graceful shutdown. 2. Close incoming boundaries. For example, stop accepting new tasks for processing from queue, stop handling new incoming http requests, etc. Graceful shutdown 80
81. 3. Set a forced timeout for completion current tasks or save them for future processing. Recommended value for this timeout is not more then 5 second. 4. Notify consumers about shutdown. For example, send heartbeat-shutdown. Graceful shutdown 81
82. 5. Correctly disconnect from all connections. For example, database, RabbitMQ, Redis, etc. 6. Log finish of graceful shutdown and stop the process. Graceful shutdown 82
83. 83 Let’s summarize!
84. ▰ Reusable Components ▰ Monolith First ▰ The Twelve Factors ▰ EСB (Entity, Boundary, Control) Pattern ▰ Bootstrapping and Graceful shutdown Microservice Best Practises 84
85. 85 Robustness Engineered for engineers Useful Simple Examples included
89. 89 Thank you for attention! Be consistent in your microservices!!! You can find me on Twitter as @galk_in Slides are available at speakerdeck.com/galkin or on my site galk.in
90. Slides JSFest bot
91. ▰ koa ▰ bunyan ▰ dotenv-safe ▰ gatsbyjs ▰ rxjs My favorite packages 91 ▰ pre-commit ▰ eslint ▰ jest ▰ raml-cli ▰ dredd