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Optimizing Enterprise Javafor a Microservices Architecture

John Clingan, middle-aged Java EE guy and MicroProfile-rEmily Jiang, totally awesome MicroProfile engineer

Eclipse

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Agenda

MicroProfile Overview (~10 Minutes)

Example Specs - From concept to implementation (10 minutes)

Collaborate (Until they kick us out or we want to go for a beer)

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Enterprise Java Standards History

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What is MicroProfile?

A community of individuals, organizations, and vendors …

… collaborating within an open source (Eclipse) project ….

… to bring microservices to the Enterprise Java community

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Innovation vs Standardization

(Open Source) Project Focused Standard (JSR) focused

(Java EE)(MicroProfile)

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Innovation vs Standardization

(Open Source) Project Focused Standard (JSR) focused

(Java EE)

Large multi-feature releasesIncremental feature release

(MicroProfile)

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Innovation vs Standardization

Spec Lead controls pace

(Open Source) Project Focused Standard (JSR) focused

(Java EE)

Large multi-feature releasesIncremental feature release

(MicroProfile)

Community controls pace

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Accelerating* Adoption of MicroServices

2016 2017 2018 2019

8 9

1.0

1.1

1.2

1.3

1.4

2020

1.5

* 2-4 releases per year

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MicroProfile 1.0 (Sep, 2016)

Contexts and Dependency Injection (CDI 1.1)

+

Java API for RESTful Web Services (JAX-RS 2.0)

+

Java API for JSON Processing (JSON-P 1.0)

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MicroProfile 1.1 Underway

Security: JWT Token Exchange 1.0

Health Check 1.0

Configuration 1.0

Fault Tolerance 1.0 (Stretch goal)

Second Quarter2017!

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Will MicroProfile Features be in Java EE?

Possibly

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MicroProfile Java Programming Model(In Progress)

● Config

● Fault Tolerance

● Health Checker

● Metrics

● Security

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Configuration

● Discussed with a formal proposal in the MicroProfile mailing list (https://groups.google.com/forum/#!topic/microprofile/VJEEAOsVj5E[26-50])

● After the proposal was accepted, a repository was created to draft APIs/SPIs (https://github.com/eclipse/microprofile-config/)

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MicroProfile Java Prog. Model - Configuration

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MicroProfile Java Prog. Model - ConfigurationUsing CDI Injection

@Inject Config config; Inject all config properties that the class can see

@Inject @ConfigProperty(name=“myProp” defaultValue=“blah”)String prop1;

Inject the value of the property called “myProp”. The value of prop1 will not be refreshed. Suitable for static properties and used on the RequestScoped beans.

@Inject @ConfigProperty(name=“myProp” defaultValue=“blah”) Provider<String> prop1

Inject the value of the property called “myProp” and it picks up the dynamic changes.

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MicroProfile Java Prog. Model - ConfigurationProgrammatic lookup

ConfigProvider.getConfig(); The config object containing all properties that the class owner can see.

ConfigProvider.getBuilder() .addDefaultSources() .withSources(…).build();

Create a custom config object

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MicroProfile Java Prog. Model - Configuration● The property file, microprofile-config.properties, packaged in the application can be

overwritten by :○ System variables (400 as the default priority) ○ Environment variables (300 as the default priority) or ○ a custom property files with a higher priority than microprofile-config.properties

(100 as the default priority).

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MicroProfile Java Prog. Model - config

● Plan to finalise the current APIs/SPIs and release the Config 1.0 by mid April

● Then work on the new features of Config 1.1

● Join in the Config discussion

● Join in the Config hangout – on Thursdays

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MicroProfile Java Prog model –Fault Tolerance

● Proposal discussion: https://groups.google.com/forum/#!topic/microprofile/ESs9L3z08oA

● Prototype (inspired by Failsafe): https://github.com/Emily-Jiang/microprofile-faultTolerance-incubation

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MicroProfile Java Prog model –Fault Tolerance

Retry The request should have a retry to recover from temporary glitches

Fallback The request should have a fallback operation if retry fails

Timeout The request must have a timeout, to prevent from waiting indefinitely

Circuit Breaker The request must prevent from repeating timeouts

Bulkhead One part of application failure must not bring the whole application down

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Fault Tolerance - Fallback Retry

Set up retry policy and wrap the call with the policy and specify the fallback operationFaultToleranceFactory.getFaultToleranceType(RetryPolicy.class);

Duration delay = Duration.ofSeconds(1);retryPolicy = retryPolicy.retryOn(Exception.class).withDelay(delay) .withMaxRetries(3);

Runnable fallbackService = () -> serviceB();executor.with(retryPolicy).withFallback(fallbackService) .run(mainService);

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Fault Tolerance - Circuit Breaker TimeoutFail-fast, temporarily disable the running of a servicecircuitBreaker = FaultToleranceFactory.getFaultToleranceType(CircuitBreaker.class);circuitBreaker = circuitBreaker.withTimeout(timeout).withFailureThreshold(3) .withSuccessThreshold(2) .withDelay(delay);

Callable<Object> mainService = () -> serviceA();Executor executor = FaultToleranceFactory.getFaultToleranceType(Executor.class);

executor.with(circuitBreaker).get(mainService);

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Fault Tolerance - Bulkhead

Limit the number of concurrent calls to a service

ThreadPoolExecutor tpexecutor = new ThreadPoolExecutor( poolSize, poolSize, 0, TimeUnit.SECONDS, new ArrayBlockingQueue<Runnable>(10));

bulkhead = bulkhead.withThread(tpexecutor);executor.with(bulkhead) .run(mainService);

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MicroProfile Java Prog model –Fault Tolerance

● Non-CDI approach was left out of the first release but focus on CDI-first approach

● Discussion the CDI-first approach ongoing● Use Interceptor to apply policy and use annotation to config policy

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Health Check, Metrics, Security

● Health Check – proposal accepted

● Metrics and Security – proposal in discussion

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Join the Community!

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Resources

MicroProfile.io

MicroProfile Discussion Forumbit.ly/MicroProfileForum

MicroProfile Exampleshttps://github.com/microprofile/microprofile-samples