Can't use logback for Android JUnit in Android Studio?

[Gohan]

I had put "logback.xml" in
src\test\assets\logback.xml
src\main\assets\logback.xml
src\androidTest\assets\logback.xml

but seems it still not working

logback file below:

<configuration debug='true'>
    <property name="LOG_DIR" value="/sdcard/logback" />
    <appender name="LOG_CAT_APPENDER" class="ch.qos.logback.classic.android.LogcatAppender">
        <encoder class="demo2017.demos.baozs.com.common.logback.ExtendedPatternLayoutEncoder">
            <pattern>%d{HH:mm:ss.SSS} %PID %TID [%thread] %-5level %logger{36} - %msg%n</pattern>
        </encoder>
    </appender>
    <appender name="LOG_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOG_DIR}/logfile.log</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <fileNamePattern>${LOG_DIR}/logfile.%d{yyyy-MM-dd}.log.gz</fileNamePattern>
            <maxHistory>7</maxHistory>
            <totalSizeCap>1GB</totalSizeCap>
        </rollingPolicy>
        <encoder class="demo2017.demos.baozs.com.common.logback.ExtendedPatternLayoutEncoder">
            <pattern>%d{HH:mm:ss.SSS} %-4relative %PID %TID [%thread] %-5level %logger{35} - %msg %n</pattern>
        </encoder>
    </appender>
    <appender name="FLOW_LOG_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${LOG_DIR}/flow_logfile.log</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <fileNamePattern>${LOG_DIR}/flow_logfile.%d{yyyy-MM-dd}.log.gz</fileNamePattern>
            <maxHistory>7</maxHistory>
            <totalSizeCap>1GB</totalSizeCap>
        </rollingPolicy>
        <encoder class="demo2017.demos.baozs.com.common.logback.ExtendedPatternLayoutEncoder">
            <pattern>%d{HH:mm:ss.SSS} %-4relative %PID %TID [%thread] %-5level %logger{35} - %msg %n</pattern>
        </encoder>
    </appender>
    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <pattern>%d{HH:mm:ss.SSS} %PID %TID [%thread] %-5level %logger{36} - %msg</pattern>
        </encoder>
    </appender>
    <root level="DEBUG">
        <appender-ref ref="LOG_CAT_APPENDER" />
        <appender-ref ref="LOG_FILE" />
    </root>
    <logger name="flow" level="DEBUG" additivity="false">
        <appender-ref ref="FLOW_LOG_FILE"/>
    </logger>
    <logger name="test" level="DEBUG" additivity="false">
        <appender-ref ref="STDOUT"/>
    </logger>
</configuration>

after some trying

add
testCompile 'ch.qos.logback:logback-classic:1.2.3'

it works but got Class path contains multiple SLF4J bindings. warning..

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[Gohan]

Still unsolved

[cleemansen]

I can not see any output in my JUnit-Tests also. I got the following exception:

Failed to instantiate [ch.qos.logback.classic.LoggerContext]
Reported exception:
java.lang.RuntimeException: Method getExternalStorageState in android.os.Environment not mocked. See http://g.co/androidstudio/not-mocked for details.
	at android.os.Environment.getExternalStorageState(Environment.java)
	at ch.qos.logback.core.android.AndroidContextUtil.getMountedExternalStorageDirectoryPath(Unknown Source)
	at ch.qos.logback.core.android.AndroidContextUtil.setupProperties(Unknown Source)
	at ch.qos.logback.classic.util.ContextInitializer.autoConfig(Unknown Source)
	at org.slf4j.impl.StaticLoggerBinder.init(Unknown Source)
	at org.slf4j.impl.StaticLoggerBinder.<clinit>(Unknown Source)
	at org.slf4j.LoggerFactory.bind(LoggerFactory.java:150)
	at org.slf4j.LoggerFactory.performInitialization(LoggerFactory.java:124)
	at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:412)
	at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:357)
	at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:383)
	at com.couchbits.presence.data.sync.SyncEngine.<clinit>(SyncEngine.java:29)
	at com.couchbits.presence.data.sync.SyncEngineTest.setUp(SyncEngineTest.java:81)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
	at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:24)
	at org.junit.rules.ExpectedException$ExpectedExceptionStatement.evaluate(ExpectedException.java:239)
	at org.junit.rules.RunRules.evaluate(RunRules.java:20)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
	at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
	at org.mockito.internal.runners.JUnit45AndHigherRunnerImpl.run(JUnit45AndHigherRunnerImpl.java:37)
	at org.mockito.runners.MockitoJUnitRunner.run(MockitoJUnitRunner.java:62)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

Adding testImplementation 'ch.qos.logback:logback-classic:1.2.3' will print the log into my Android-Studio-Console. But I get also the SLF4J: Class path contains multiple SLF4J bindings. warning.

Any advice how to setup a correct JUnit-Test-Setup?

[almozavr]

@cleemansen could you provide your build.gradle and config? I'm having java.lang.NoSuchMethodError: ch.qos.logback.core.util.Loader.getResources when trying to add testImplementation 'ch.qos.logback:logback-classic:1.2.3'

[cleemansen]

@almozavr snippet of my build.gradle (i'm sending my logs to papertrail w/ that setup):

    // cloud logging
    implementation 'org.slf4j:slf4j-api:1.7.25'
    implementation 'com.github.tony19:logback-android:1.3.0-3'
    implementation ('com.papertrailapp:logback-syslog4j:1.0.0') {
        exclude group: 'ch.qos.logback'
    }
    // better than nothing :/ https://github.com/tony19/logback-android/issues/151
    testImplementation 'ch.qos.logback:logback-classic:1.2.3'

My logback config is very specific. This setup "works" as described in my last comment w/ a simple console appender.

[almozavr]

I tried dependency substitution but gradle + android doesn't work that way 😖

dependenices {
    implementation "com.github.tony19:logback-android:$logbackAndroidVersion"
}

configurations.all { config ->
    if (config.name.toLowerCase().contains('test')) {
        println "Replacing module in configuration " + config.name
        config.resolutionStrategy.dependencySubstitution {
            substitute module("com.github.tony19:logback-android:$logbackAndroidVersion") with module("ch.qos.logback:logback-classic:$logbackVersion")
        }
    }
}

[almozavr]

@cleemansen I'm afraid, your solution is unreliable -> slf4j takes first "random" binding if there are multiple, it comes from their documentation, and actually I encountered it today..

[cleemansen]

I'm also not happy w/ that workaround.
Thanks for your "random" binding hint @almozavr! Did not recognized this behavior yet. But you need the logs the first time when the tests are red.. :/

I had the same idea substituting the libraries, too. Never tried it and I don't know if this approach is worthwhile.

[almozavr]

@cleemansen dep. substitution works great with vanilla gradle (executed from terminal), but it seems like Android Studio uses diff classpath rules, so it simple skips configuration rules for inbound test runs 😢

[tony19]

Local unit tests that use logback-android must be run with Robolectric, or else they'll hit this exception:

java.lang.RuntimeException: Method getExternalStorageState in android.os.Environment not mocked. See http://g.co/androidstudio/not-mocked for details.
  at android.os.Environment.getExternalStorageState(Environment.java)
  ...

If you cannot use Robolectric in your project for some reason, those tests must be moved to instrumented unit tests, which run on an emulator or device. See Android docs on testing for more information.

Setup:

1. Add org.robolectric:robolectric to your app's build.gradle test dependencies:

dependencies {
  testImplementation 'org.robolectric:robolectric:3.8'
}

2. Annotate your unit test class to run with with RobolectricTestRunner:

import org.junit.runner.RunWith;
import org.robolectric.RobolectricTestRunner;

@RunWith(RobolectricTestRunner.class)
public class ExampleUnitTest { ... }

3. Add src/test/resources/assets/logback.xml with XML config. Note the resources subdirectory. Example config:

<configuration debug="true">
  <appender name="console" class="ch.qos.logback.core.ConsoleAppender">
    <encoder>
      <pattern>%msg</pattern>
    </encoder>
  </appender>

  <root level="DEBUG">
    <appender-ref ref="console" />
  </root>
</configuration>

4. Add src/test/AndroidManifest.xml to silence a Robolectric warning. Alternatively, you could annotate your unit test class:

import org.robolectric.annotation.Config;

@Config(manifest = Config.NONE)
public class ExampleUnitTest { ... }

See changes in tony19-sandbox/logback-test-app@4682f5a

[almozavr]

@tony19 thanks for the so much detailed example! I believe it would be great to mention this sample app repo at readme or include in the main repo.

Also, I consider Robolectric is a valid option, I believe logback is not a best driver to stick with this framework, especially today when kotlintest or spek are so common. So if you gonna mention about android unit tests and robolectric, I'd propose to mention gradle's dependency substitution trick (see comments from above). If you need any assistance, I would be glad to help.

[tony19]

I believe it would be great to mention this sample app repo at readme or include in the main repo.

That repo is currently for CI only, but I might clean it up as a general sample app.

Also, I consider Robolectric is a valid option, I believe logback is not a best driver to stick with this framework, especially today when kotlintest or spek are so common

Robolectric is supplemental to unit test frameworks, such as kotlintest. It allows your unit tests to access Android classes (e.g., android.os.Environment) without running on an emulator or device. You could use Robolectric with kotlintest. Update: Turns out Robolectric requires JUnit 4, which kotlintest does not support any longer. As almozavr pointed out, Robolectric and kotlintest are not yet compatible.

[almozavr]

@tony19 I'm afraid, it's not that straightforward in the world of junit 4 and 5 and their runners, e.g.:
kotest/kotest#189

Anyway, I doubt one would stick with Robolectric to run vanilla unit tests just because of the logger tool..