airframe-control: Add CircuitBreaker

[xerial]

Implements #758

CircuitBreaker States:

• closed
  • Requests will be processed
• open
  • Throws an exception (fail-fast) to protect the external service
  • Wait until a given delay timeout (backoff), then move to half-open state
• half-open
  • try to send a request
    • success: move to closed state
    • failure: move to open state

tasks

• Integration with Retry
• Use RetryPolicy for backoff delay
• Add the capability to monitor the state of CircuitBreaker to know which external services were not working.
• Integration with airframe-http-client (async based implementation) -> Added stand-alone mode to support this usage

Related work:

• https://doc.akka.io/docs/akka/current/common/circuitbreaker.html
• https://monix.io/docs/2x/eval/circuit-breaker.html
• https://github.com/jhalterman/failsafe/blob/master/src/main/java/net/jodah/failsafe/CircuitBreaker.java
• https://github.com/twitter/finagle/blob/develop/finagle-core/src/main/scala/com/twitter/finagle/liveness/FailureAccrualFactory.scala

[codecov]

Codecov Report

Merging #763 into master will increase coverage by 0.45%.
The diff coverage is 76.38%.

@@            Coverage Diff             @@
##           master     #763      +/-   ##
==========================================
+ Coverage   81.03%   81.48%   +0.45%     
==========================================
  Files         228      237       +9     
  Lines        9004     9236     +232     
  Branches      651      668      +17     
==========================================
+ Hits         7296     7526     +230     
- Misses       1708     1710       +2

Impacted Files	Coverage Δ
...src/main/scala/wvlet/airframe/control/Ticker.scala	0% <ø> (ø)	⬆️
...a/wvlet/airframe/sql/analyzer/QuerySignature.scala	77.77% <ø> (ø)	⬆️
...wvlet/airframe/sql/analyzer/InOutTableFinder.scala	95.45% <ø> (ø)	⬆️
.../wvlet/airframe/sql/model/LogicalPlanPrinter.scala	100% <100%> (ø)	⬆️
...la/wvlet/airframe/sql/analyzer/SQLAnonymizer.scala	75% <100%> (+0.71%)	⬆️
...rframe/control/util/ExponentialMovingAverage.scala	100% <100%> (ø)
...ala/wvlet/airframe/jdbc/SQLiteConnectionPool.scala	92.3% <100%> (ø)	⬆️
...la/wvlet/airframe/jdbc/ConnectionPoolFactory.scala	100% <100%> (ø)
...rc/main/scala/wvlet/airframe/control/Control.scala	100% <100%> (ø)	⬆️
...scala/wvlet/airframe/sql/parser/SQLGenerator.scala	87.5% <50%> (ø)	⬆️
... and 28 more

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[xerial]

@takezoe I think this supports the basic functionality of circuit breaker that can be configured to our use case.

[xerial]

@takezoe I think creating a snapshot version of this CircuitBreaker is better for testing this. So let me merge it and fix the implementation as we find ideas for improving the design.