Spring forward: an introduction to Spring boot and Thymeleaf for ICS developers

The world of a ICS developer is moving fast. Customers rethinking platforms and solutions. Spring Boot makes it easy to create stand-alone, production-grade Spring based Applications that you can “just run”. In combination with Thymeleaf can it be good alternative for your Domino applications. In this session I give an introduction of Spring Boot and Thymeleaf and how to get started. I will show the differences and similarities between Spring Boot in combination with Thymeleaf and XPages. I will explain the challenges I faced when moving an application.

Transcript

1. Spring forward
   an introduction to Spring boot and Thymeleaf for
   developers
   Frank van der Linden
   Full stack Developer
   

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2. Social Connections 15 Munich, September 16-18 2019
   

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3. Social Connections 15 Munich, September 16-18 2019
   About me
   • Freelance Full stack developer
   • Owner of elstar IT
   • Curious of new technology
   • IBM Champion 2013, 2014, 2017, 2018 and 2019
   • HCL Master 2019
   

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4. Social Connections 15 Munich, September 16-18 2019
   How to proceed
   • What is Spring boot and Thymeleaf
   • How to start
   • Syntax
   • Security
   • Bonus - new possibilities
   

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5. Social Connections 15 Munich, September 16-18 2019
   Spring Forward Starter - demo project
   https://github.com/flinden68/spring-forward-starter
   

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6. Social Connections 15 Munich, September 16-18 2019
   What is Spring boot and Thymeleaf
   

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7. Social Connections 15 Munich, September 16-18 2019
   

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8. Social Connections 15 Munich, September 16-18 2019
   Spring boot
   • Open source, Pivotal is coordinating the releases
   • Spring boot creates Spring (Java) based applications
   • Embedded Tomcat makes it ‘just’ run everywhere
   • Auto configure as much as possible
   • Built in metrics and health checks
   • Easy to configure with YAML or property file
   • Very good documentation and code examples
   • Fast creation of REST api’s
   

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9. Social Connections 15 Munich, September 16-18 2019
   Runs everywhere
   • With Embedded Tomcat as default the jar ‘just run’
   • More choices of embedded web server, like Netty
   • Will run on Docker
   • Will run on Cloud Foundry, like IBM Cloud or Pivotal on Azure
   • Tomcat can by excluding to run it on Websphere Application
   Server, Tomcat or WildFly (a.k.a JBoss)
   • Even on Domino as OSGi plugin, http://hasselba.ch/blog/?
   p=2589
   

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10. Social Connections 15 Munich, September 16-18 2019
    Thymeleaf
    • Is a template engine, like XPages or Freemarker
    • Based on Java and HTML5
    • Very strict, or template will break
    • Full Spring framework support
    • Extensible with dialects
    • Full (and extensible) internationalisation support.
    • Reusable fragments, like Custom Controls
    • Extensive documentation
    

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11. Social Connections 15 Munich, September 16-18 2019
    How to start
    

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12. Social Connections 15 Munich, September 16-18 2019
    How to start
    • Install Gradle or Maven
    • Move over to start.spring.io
    • Or use the Starter in IntelliJ
    • Fill all the fields and select the required projects (full
    version)
    • Generate project
    • Download zip, unzip and add to Git repository.
    • Open project in favourite IDE, run ‘mvn clean install’
    • Start coding
    

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13. Social Connections 15 Munich, September 16-18 2019
    Wizard in IntelliJ
    

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14. Social Connections 15 Munich, September 16-18 2019
    Spring boot setup
    minimal YAML property file
    

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15. Social Connections 15 Munich, September 16-18 2019
    Thymeleaf setup
    add to pom.xml
    

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16. Social Connections 15 Munich, September 16-18 2019
    How it works together
    

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17. Social Connections 15 Munich, September 16-18 2019
    Syntax
    

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18. Social Connections 15 Munich, September 16-18 2019
    Spring boot syntax
    endpoint to return an object as JSON
    endpoint to return a thymeleaf template
    

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19. Social Connections 15 Munich, September 16-18 2019
    Component scan
    • Component scan will scan all the packages for @Service,
    @Controller, @Repository and more @Component(s)
    • @Autowired will glue everything together
    

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20. Social Connections 15 Munich, September 16-18 2019
    Thymeleaf syntax
    • Include the th namespace to the page
    • Every html element attribute has a th:…. Equivalent.
    • Variable Expressions: ${...}
    • Selection Variable Expressions: *{...}
    • Message Expressions: #{...}
    • Link URL Expressions: @{...}
    

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21. Social Connections 15 Munich, September 16-18 2019
    Namespace
    
    

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22. Social Connections 15 Munich, September 16-18 2019
    Thymeleaf attributes
    

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23. Social Connections 15 Munich, September 16-18 2019
    Variable Expressions
    

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24. Social Connections 15 Munich, September 16-18 2019
    Selection Variable Expressions
    

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25. Social Connections 15 Munich, September 16-18 2019
    Message Expressions
    

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26. Social Connections 15 Munich, September 16-18 2019
    Link URL Expressions
    resource links
    links in on a page
    

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27. Social Connections 15 Munich, September 16-18 2019
    Global objects
    

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28. Social Connections 15 Munich, September 16-18 2019
    Fragments (1)
    

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29. Social Connections 15 Munich, September 16-18 2019
    Fragments (2)
    fragment code
    use it multiple times
    

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30. Social Connections 15 Munich, September 16-18 2019
    Attachments
    • Forget the UploadedFile provided by IBM, learn
    MultipartFile
    • MultipartFile has lots of similarities with UploadedFile, but
    easier to use. Less code to achieve the same
    

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31. Social Connections 15 Munich, September 16-18 2019
    Security
    

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32. Social Connections 15 Munich, September 16-18 2019
    Spring Security
    • Framework for Authentication and Authorisation
    • Prevention of clickjacking, CORS, cross site request
    forgery
    • Integrates with Spring Boot and Thymeleaf
    • Customisable to the bone
    • Support for Basic Authentication, SAML2, oAuth and
    more.
    

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33. Social Connections 15 Munich, September 16-18 2019
    Configuration
    CORS prevention
    add to pom.xml
    

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34. Social Connections 15 Munich, September 16-18 2019
    Spring security in Thymeleaf
    add to pom.xml
    add namespace
    

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35. Social Connections 15 Munich, September 16-18 2019
    Bonus - new possibilities
    

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36. Social Connections 15 Munich, September 16-18 2019
    Lombok
    • Forget Getters and Setters
    • Forget toString, hashCode and equals
    • One @Annotations rules the all (@Data or @Getter and
    @Setter)
    • Add logging by @annotations (@Log4j2 or @Slf4j)
    

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37. Social Connections 15 Munich, September 16-18 2019
    Lombok
    add to pom.xml
    add @Data
    using the build in logging
    

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38. Social Connections 15 Munich, September 16-18 2019
    Swagger
    • Part of Open API Specification, since v3
    • Documentation of API’s
    • Playground for testing
    • Add annotation to generate the documentation
    dynamically
    

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39. Social Connections 15 Munich, September 16-18 2019
    Swagger
    add to pom.xml
    add a configuration
    add annotation to endpoint
    

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40. Social Connections 15 Munich, September 16-18 2019
    Jenkins
    • With Jenkins you can build automatically the application
    • …But also do quality control, do load tests and even
    deploy.
    • JenkinsFile should be in the root of the GIT Repository
    • Groovy is the language for JenkinsFile
    

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41. Social Connections 15 Munich, September 16-18 2019
    Jenkins file
    

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42. Social Connections 15 Munich, September 16-18 2019
    Questions
    

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43. Social Connections 15 Munich, September 16-18 2019
    Reach out to me
    @flinden68
    https://www.elstarit.nl
    flinden68@elstarit.nl
    https://nl.linkedin.com/in/flinden68
    https://github.com/flinden68
    

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44. Social Connections 15 Munich, September 16-18 2019
    Resources
    •Spring Initializr
    •http://start.spring.io/
    •Thymeleaf documentation
    •http://www.thymeleaf.org/
    •Spring Boot
    • https://projects.spring.io/spring-boot/
    •Lombok
    • https://projectlombok.org/
    •Jenkins
    • https://jenkins.io/
    

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45. Social Connections 15 Munich, September 16-18 2019
    Resources
    •Swagger
    •http://swagger.io
    •Thymeleaf documentation
    •http://www.thymeleaf.org/
    •Maven
    • https://maven.apache.org/
    •Gradle
    • https://gradle.org/
    •Spring Forward Starter
    • https://github.com/flinden68/spring-forward-starter
    

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46. Social Connections 15 Munich, September 16-18 2019
    

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