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SEBSERV-60 implemented

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This commit is contained in:
anhefti 2019-09-02 12:56:32 +02:00
parent cf948d5827
commit 7a8cdf0ee3
7 changed files with 119 additions and 44 deletions
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20
src/main/java/ch/ethz/seb/sebserver/gbl/async/AsyncService.java
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@ -40,18 +40,23 @@ public class AsyncService {
timeToRecover);
}
public <T> MemoizingCircuitBreaker<T> createMemoizingCircuitBreaker(
final Supplier<T> blockingSupplier) {
return new MemoizingCircuitBreaker<>(this.asyncRunner, blockingSupplier, true);
}
// public <T> MemoizingCircuitBreaker<T> createMemoizingCircuitBreaker(
// final Supplier<T> blockingSupplier) {
//
// return new MemoizingCircuitBreaker<>(
// this.asyncRunner,
// blockingSupplier,
// true,
// Constants.HOUR_IN_MILLIS);
// }
public <T> MemoizingCircuitBreaker<T> createMemoizingCircuitBreaker(
final Supplier<T> blockingSupplier,
final int maxFailingAttempts,
final long maxBlockingTime,
final long timeToRecover,
final boolean momoized) {
final boolean momoized,
final long maxMemoizingTime) {
return new MemoizingCircuitBreaker<>(
this.asyncRunner,
@ -59,7 +64,8 @@ public class AsyncService {
maxFailingAttempts,
maxBlockingTime,
timeToRecover,
momoized);
momoized,
maxMemoizingTime);
}
}

20
src/main/java/ch/ethz/seb/sebserver/gbl/async/CircuitBreaker.java
View file

@ -102,6 +102,26 @@ public final class CircuitBreaker<T> {
this.timeToRecover = timeToRecover;
}
public int getMaxFailingAttempts() {
return this.maxFailingAttempts;
}
public long getMaxBlockingTime() {
return this.maxBlockingTime;
}
public long getTimeToRecover() {
return this.timeToRecover;
}
public AtomicInteger getFailingCount() {
return this.failingCount;
}
public long getLastSuccessTime() {
return this.lastSuccessTime;
}
public Result<T> protectedRun(final Supplier<T> supplier) {
final long currentTime = System.currentTimeMillis();

42
src/main/java/ch/ethz/seb/sebserver/gbl/async/MemoizingCircuitBreaker.java
View file

@ -54,21 +54,42 @@ public final class MemoizingCircuitBreaker<T> implements Supplier<Result<T>> {
private final Supplier<T> supplier;
private final boolean memoizing;
private final long maxMemoizingTime;
private long lastMemoizingTime = 0;
private Result<T> cached = null;
/** Create new CircuitBreakerSupplier.
*
* @param asyncRunner the AsyncRunner used to create asynchronous calls on the given supplier function
* @param supplier The Supplier function that can fail or block for a long time
* @param memoizing whether the memoizing functionality is on or off */
* @param memoizing whether the memoizing functionality is on or off
* @param maxMemoizingTime the maximal time memorized data is valid */
MemoizingCircuitBreaker(
final AsyncRunner asyncRunner,
final Supplier<T> supplier,
final boolean memoizing) {
final boolean memoizing,
final long maxMemoizingTime) {
this.delegate = new CircuitBreaker<>(asyncRunner);
this.supplier = supplier;
this.memoizing = memoizing;
this.maxMemoizingTime = maxMemoizingTime;
}
public CircuitBreaker<T> getDelegate() {
return this.delegate;
}
public boolean isMemoizing() {
return this.memoizing;
}
public long getMaxMemoizingTime() {
return this.maxMemoizingTime;
}
public long getLastMemoizingTime() {
return this.lastMemoizingTime;
}
/** Create new CircuitBreakerSupplier.
@ -79,14 +100,16 @@ public final class MemoizingCircuitBreaker<T> implements Supplier<Result<T>> {
* @param maxBlockingTime the maximal time that an call attempt can block until an error is responded
* @param timeToRecover the time the circuit breaker needs to cool-down on OPEN-STATE before going back to HALF_OPEN
* state
* @param memoizing whether the memoizing functionality is on or off */
* @param memoizing whether the memoizing functionality is on or off
* @param maxMemoizingTime the maximal time memorized data is valid */
MemoizingCircuitBreaker(
final AsyncRunner asyncRunner,
final Supplier<T> supplier,
final int maxFailingAttempts,
final long maxBlockingTime,
final long timeToRecover,
final boolean memoizing) {
final boolean memoizing,
final long maxMemoizingTime) {
this.delegate = new CircuitBreaker<>(
asyncRunner,
@ -95,6 +118,7 @@ public final class MemoizingCircuitBreaker<T> implements Supplier<Result<T>> {
timeToRecover);
this.supplier = supplier;
this.memoizing = memoizing;
this.maxMemoizingTime = maxMemoizingTime;
}
@Override
@ -102,10 +126,15 @@ public final class MemoizingCircuitBreaker<T> implements Supplier<Result<T>> {
final Result<T> result = this.delegate.protectedRun(this.supplier);
if (result.hasError()) {
if (this.memoizing && this.cached != null) {
if (log.isDebugEnabled()) {
log.debug("Return cached at: {}", System.currentTimeMillis());
final long currentTimeMillis = System.currentTimeMillis();
if (currentTimeMillis - this.lastMemoizingTime > this.maxMemoizingTime) {
if (log.isDebugEnabled()) {
log.debug("Max memoizing time reached. Return original error");
}
return result;
}
log.warn("Return cached at: {}", System.currentTimeMillis());
return this.cached;
}
@ -117,6 +146,7 @@ public final class MemoizingCircuitBreaker<T> implements Supplier<Result<T>> {
}
this.cached = result;
this.lastMemoizingTime = System.currentTimeMillis();
}
return result;
}

9
src/main/java/ch/ethz/seb/sebserver/webservice/servicelayer/lms/impl/OpenEdxLmsAPITemplate.java
View file

@ -46,6 +46,7 @@ import org.springframework.security.oauth2.common.OAuth2AccessToken;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import ch.ethz.seb.sebserver.gbl.Constants;
import ch.ethz.seb.sebserver.gbl.api.APIMessage;
import ch.ethz.seb.sebserver.gbl.async.AsyncService;
import ch.ethz.seb.sebserver.gbl.async.MemoizingCircuitBreaker;
@ -97,7 +98,13 @@ final class OpenEdxLmsAPITemplate implements LmsAPITemplate {
this.knownTokenAccessPaths.addAll(Arrays.asList(alternativeTokenRequestPaths));
}
this.allQuizzesSupplier = asyncService.createMemoizingCircuitBreaker(allQuizzesSupplier());
this.allQuizzesSupplier = asyncService.createMemoizingCircuitBreaker(
allQuizzesSupplier(),
3,
Constants.MINUTE_IN_MILLIS,
Constants.MINUTE_IN_MILLIS,
true,
Constants.HOUR_IN_MILLIS);
}
@Override

32
src/test/java/ch/ethz/seb/sebserver/gbl/async/MemoizingCircuitBreakerTest.java
View file

@ -42,7 +42,7 @@ public class MemoizingCircuitBreakerTest {
@Test
public void roundtrip1() throws InterruptedException {
final MemoizingCircuitBreaker<String> circuitBreaker = this.asyncService.createMemoizingCircuitBreaker(
tester(100, 5, 10), 3, 500, 1000, true);
tester(100, 5, 10), 3, 500, 1000, true, 1000);
assertNull(circuitBreaker.getChached());
@ -84,13 +84,39 @@ public class MemoizingCircuitBreakerTest {
}
@Test
public void failing() throws InterruptedException {
final MemoizingCircuitBreaker<String> circuitBreaker = this.asyncService.createMemoizingCircuitBreaker(
tester(50, 1, 10), 3, 100, 100, true, 1000);
assertNull(circuitBreaker.getChached());
// fist call okay.. for memoizing
Result<String> result = circuitBreaker.get(); // 1. call...
assertFalse(result.hasError());
assertEquals("Hello", result.get());
assertTrue(circuitBreaker.getLastMemoizingTime() > 0);
// second call is okay from memoizing
Thread.sleep(100);
result = circuitBreaker.get(); // 2. call...
assertFalse(result.hasError());
assertEquals("Hello", result.get());
assertTrue(circuitBreaker.getLastMemoizingTime() > 0);
// third call is failing because of memoizing timeout
Thread.sleep(1000);
result = circuitBreaker.get(); // 3. call...
assertTrue(result.hasError());
}
private Supplier<String> tester(final long delay, final int unavailableAfter, final int unavailableUntil) {
final AtomicInteger count = new AtomicInteger(0);
final AtomicBoolean wasUnavailable = new AtomicBoolean(false);
return () -> {
final int attempts = count.getAndIncrement();
log.info("tester answers {} {}", attempts, Thread.currentThread());
log.debug("tester answers {} {}", attempts, Thread.currentThread());
try {
Thread.sleep(delay);
@ -107,6 +133,4 @@ public class MemoizingCircuitBreakerTest {
};
}
// TODO timeout test: test also the behavior on timeout, is the thread being interrupted and released or not (should!)
}

14
src/test/resources/logback-test.xml Normal file
View file

@ -0,0 +1,14 @@
<?xml version="1.0" encoding="UTF-8"?>
<configuration debug="false" scan="false">
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>%d{HH:mm:ss.SSS} %-5level [%thread]:[%logger] %msg%n</pattern>
</encoder>
</appender>
<Logger name="org.eth.demo.sebserver" level="TRACE" additivity="true" />
<root level="INFO" additivity="true">
<appender-ref ref="STDOUT" />
</root>
</configuration>

26
src/test/resources/logback.xml
View file

@ -1,26 +0,0 @@
<?xml version="1.0" encoding="UTF-8"?>
<configuration debug="false" scan="false">
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<encoder>
<pattern>%d{HH:mm:ss.SSS} %-5level [%thread]:[%logger] %msg%n</pattern>
</encoder>
</appender>
<Logger name="org.eth.demo.sebserver" level="INFO" additivity="true" />
<Logger name="org.mybatis.generator" level="INFO" additivity="true" />
<Logger name="org.eth.demo.sebserver.batis" level="INFO" additivity="true" />
<Logger name="org.springframework.security" level="INFO" additivity="true" />
<Logger name="org.springframework.security.oauth2" level="INFO" additivity="true" />
<Logger name="org.springframework.web.socket.messaging" level="INFO" additivity="true" />
<Logger name="org.springframework.messaging" level="INFO" additivity="true" />
<Logger name="org.springframework" level="INFO" additivity="true" />
<Logger name="org.springframework.web" level="INFO" additivity="true" />
<Logger name="org.eth.demo.sebserver.batis.gen.mapper.ExamRecordMapper" level="INFO" additivity="true" />
<root level="INFO" additivity="true">
<appender-ref ref="STDOUT" />
</root>
</configuration>