CircuitBreakerMetricsTest.java

/*
 *
 *  Copyright 2016 Robert Winkler
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *
 */
package io.github.resilience4j.circuitbreaker.internal;

import org.junit.Test;

import static org.assertj.core.api.Assertions.assertThat;

public class CircuitBreakerMetricsTest {

    @Test
    public void testCircuitBreakerMetrics(){
        CircuitBreakerMetrics circuitBreakerMetrics = new CircuitBreakerMetrics(10);
        assertThat(circuitBreakerMetrics.getMaxNumberOfBufferedCalls()).isEqualTo(10);

        circuitBreakerMetrics.onSuccess();
        circuitBreakerMetrics.onSuccess();
        circuitBreakerMetrics.onError();
        circuitBreakerMetrics.onError();
        circuitBreakerMetrics.onCallNotPermitted();
        circuitBreakerMetrics.onCallNotPermitted();

        assertThat(circuitBreakerMetrics.getNumberOfBufferedCalls()).isEqualTo(4);
        assertThat(circuitBreakerMetrics.getNumberOfFailedCalls()).isEqualTo(2);
        assertThat(circuitBreakerMetrics.getNumberOfSuccessfulCalls()).isEqualTo(2);
        assertThat(circuitBreakerMetrics.getNumberOfNotPermittedCalls()).isEqualTo(2);

        // The failure rate must be -1, because the number of measured calls is below the buffer size of 10
        assertThat(circuitBreakerMetrics.getFailureRate()).isEqualTo(-1);

        circuitBreakerMetrics.onError();
        circuitBreakerMetrics.onError();
        circuitBreakerMetrics.onError();
        circuitBreakerMetrics.onError();
        circuitBreakerMetrics.onSuccess();
        circuitBreakerMetrics.onSuccess();
        circuitBreakerMetrics.onSuccess();
        circuitBreakerMetrics.onSuccess();

        // 12 calls have been recorded, but only 10 are stored in the RingBitSet. 4 successes and 6 failures.
        // The failure rate must be 60%, because the number of measured calls is above the minimum number of measured calls.
        assertThat(circuitBreakerMetrics.getNumberOfBufferedCalls()).isEqualTo(10);
        assertThat(circuitBreakerMetrics.getNumberOfFailedCalls()).isEqualTo(6);
        assertThat(circuitBreakerMetrics.getNumberOfSuccessfulCalls()).isEqualTo(4);
        assertThat(circuitBreakerMetrics.getFailureRate()).isEqualTo(60);
    }

    @Test
    public void testCopyCircuitBreakerMetrics(){
        CircuitBreakerMetrics halfOpenCircuitBreakerMetrics = new CircuitBreakerMetrics(10);
        assertThat(halfOpenCircuitBreakerMetrics.getMaxNumberOfBufferedCalls()).isEqualTo(10);

        halfOpenCircuitBreakerMetrics.onSuccess();
        halfOpenCircuitBreakerMetrics.onSuccess();
        halfOpenCircuitBreakerMetrics.onError();
        halfOpenCircuitBreakerMetrics.onError();

        assertThat(halfOpenCircuitBreakerMetrics.getNumberOfBufferedCalls()).isEqualTo(4);
        assertThat(halfOpenCircuitBreakerMetrics.getNumberOfFailedCalls()).isEqualTo(2);
        assertThat(halfOpenCircuitBreakerMetrics.getNumberOfSuccessfulCalls()).isEqualTo(2);


        CircuitBreakerMetrics closedCircuitBreakerMetrics = halfOpenCircuitBreakerMetrics.copy(20);
        assertThat(closedCircuitBreakerMetrics.getMaxNumberOfBufferedCalls()).isEqualTo(20);
        assertThat(closedCircuitBreakerMetrics.getNumberOfBufferedCalls()).isEqualTo(4);
        assertThat(closedCircuitBreakerMetrics.getNumberOfFailedCalls()).isEqualTo(2);
        assertThat(closedCircuitBreakerMetrics.getNumberOfSuccessfulCalls()).isEqualTo(2);
        assertThat(closedCircuitBreakerMetrics.getNumberOfNotPermittedCalls()).isEqualTo(0);
    }
}