Log contents capture test extension

hapi-fhir-test-utilities/src/main/java/ca/uhn/test/util/BaseLogbackCaptureTestExtension.java

@@ -0,0 +1,103 @@
+package ca.uhn.test.util;
+
+import ch.qos.logback.classic.Level;
+import ch.qos.logback.classic.Logger;
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.Appender;
+import ch.qos.logback.core.filter.Filter;
+import org.junit.jupiter.api.extension.AfterEachCallback;
+import org.junit.jupiter.api.extension.BeforeEachCallback;
+import org.junit.jupiter.api.extension.ExtensionContext;
+import org.slf4j.LoggerFactory;
+
+import javax.annotation.Nonnull;
+
+public abstract class BaseLogbackCaptureTestExtension<T extends Appender<ILoggingEvent>> implements BeforeEachCallback, AfterEachCallback {
+ private final Logger myLogger;
+ private final Level myLevel;
+ private Level mySavedLevel;
+ private T myAppender = null;
+
+ protected BaseLogbackCaptureTestExtension(Logger theLogger, Level theTestLogLevel) {
+ myLogger = theLogger;
+ myLevel = theTestLogLevel;
+ }
+
+ protected BaseLogbackCaptureTestExtension(Logger theLogger) {
+ this(theLogger,null);
+ }
+
+ protected BaseLogbackCaptureTestExtension(String theLoggerName, Level theTestLogLevel) {
+ this((Logger) LoggerFactory.getLogger(theLoggerName), theTestLogLevel);
+ }
+
+ protected BaseLogbackCaptureTestExtension(String theLoggerName) {
+ this((Logger) LoggerFactory.getLogger(theLoggerName), null);
+ }
+
+ /**
+ * Get the wrapped logger
+ */
+ public Logger getLogger() {
+ return myLogger;
+ }
+
+ /**
+ * @return the capture appender.
+ */
+ public T getAppender() {
+ return myAppender;
+ }
+
+ /**
+ * Add theFilter to the capture appender.
+ * @param theFilter
+ */
+ public void addFilter(Filter<ILoggingEvent> theFilter) {
+ getAppender().addFilter(theFilter);
+ }
+
+
+ // junit wiring
+
+ public void beforeEach(ExtensionContext context) throws Exception {
+ setUp();
+ }
+
+ @Override
+ public void afterEach(ExtensionContext context) {
+ tearDown();
+ }
+
+ /**
+ * Guts of beforeEach exposed for manual lifecycle.
+ */
+ public void setUp() {
+ myAppender = buildAppender();
+ myAppender.start();
+ myLogger.addAppender(myAppender);
+ if (myLevel != null) {
+ mySavedLevel = myLogger.getLevel();
+ myLogger.setLevel(myLevel);
+ }
+ }
+
+
+ /**
+ * Guts of afterEach for manual lifecycle
+ */
+ public void tearDown() {
+ myLogger.detachAppender(myAppender);
+ myAppender.stop();
+ if (myLevel != null) {
+ myLogger.setLevel(mySavedLevel);
+ }
+ }
+
+ /**
+ * Extension point for different appenders
+ * @return a configured appender - will be started after.
+ */
+ @Nonnull
+ abstract T buildAppender();
+}

hapi-fhir-test-utilities/src/main/java/ca/uhn/test/util/LogContentsTestExtention.java

@@ -0,0 +1,54 @@
+package ca.uhn.test.util;
+
+import ch.qos.logback.classic.Logger;
+import ch.qos.logback.classic.PatternLayout;
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.Context;
+import ch.qos.logback.core.OutputStreamAppender;
+import ch.qos.logback.core.encoder.LayoutWrappingEncoder;
+import org.junit.jupiter.api.extension.AfterEachCallback;
+import org.junit.jupiter.api.extension.BeforeEachCallback;
+
+import javax.annotation.Nonnull;
+import java.io.ByteArrayOutputStream;
+import java.nio.charset.Charset;
+
+public class LogContentsTestExtention extends BaseLogbackCaptureTestExtension<OutputStreamAppender<ILoggingEvent>> implements BeforeEachCallback, AfterEachCallback {
+ final ByteArrayOutputStream myOutputStream = new ByteArrayOutputStream();
+
+ public LogContentsTestExtention(Logger theLogger) {
+ super(theLogger);
+ }
+
+ public LogContentsTestExtention(String theLoggerName) {
+ super(theLoggerName); }
+
+ @Nonnull
+ @Override
+ OutputStreamAppender<ILoggingEvent> buildAppender() {
+
+ Context context = getLogger().getLoggerContext();
+
+ PatternLayout layout = new PatternLayout();
+ layout.setContext(context);
+ layout.setPattern("%d{yyyy-MM-dd HH:mm:ss.SSS} %logger{36} - %msg%n%xEx");
+ layout.start();
+
+ LayoutWrappingEncoder<ILoggingEvent> encoder = new LayoutWrappingEncoder<>();
+ encoder.setContext(context);
+ encoder.setLayout(layout);
+ encoder.start();
+
+ OutputStreamAppender<ILoggingEvent> outputStreamAppender = new OutputStreamAppender<>();
+ outputStreamAppender.setContext(context);
+ outputStreamAppender.setEncoder(encoder);
+ outputStreamAppender.setOutputStream(myOutputStream);
+ outputStreamAppender.start();
+
+ return outputStreamAppender;
+ }
+
+ public String getLogOutput() {
+ return myOutputStream.toString(Charset.defaultCharset());
+ }
+}

hapi-fhir-test-utilities/src/main/java/ca/uhn/test/util/LogbackCaptureTestExtension.java

@@ -28,8 +28,6 @@
 import org.hamcrest.Matcher;
 import org.junit.jupiter.api.extension.AfterEachCallback;
 import org.junit.jupiter.api.extension.BeforeEachCallback;
-import org.junit.jupiter.api.extension.ExtensionContext;
-import org.slf4j.LoggerFactory;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
@@ -43,19 +41,14 @@
  *
  * The empty constructor will capture all log events, or you can name a log root to limit the noise.
  */
-public class LogbackCaptureTestExtension implements BeforeEachCallback, AfterEachCallback {
- private final Logger myLogger;
- private final Level myLevel;
- private ListAppender<ILoggingEvent> myListAppender = null;
- private Level mySavedLevel;
+public class LogbackCaptureTestExtension extends BaseLogbackCaptureTestExtension<ListAppender<ILoggingEvent>> implements BeforeEachCallback, AfterEachCallback {
 
  /**
  *
  * @param theLogger the log to capture
  */
  public LogbackCaptureTestExtension(Logger theLogger) {
- myLogger = theLogger;
- myLevel = null;
+ super(theLogger);
  }
 
  /**
@@ -64,15 +57,14 @@ public LogbackCaptureTestExtension(Logger theLogger) {
  * @param theTestLogLevel the log Level to set on the target logger for the duration of the test
  */
  public LogbackCaptureTestExtension(Logger theLogger, Level theTestLogLevel) {
- myLogger = theLogger;
- myLevel = theTestLogLevel;
+ super(theLogger, theTestLogLevel);
  }
 
  /**
  * @param theLoggerName the log name to capture
  */
  public LogbackCaptureTestExtension(String theLoggerName) {
- this((Logger) LoggerFactory.getLogger(theLoggerName));
+ super(theLoggerName);
  }
 
  /**
@@ -83,7 +75,7 @@ public LogbackCaptureTestExtension() {
  }
 
  public LogbackCaptureTestExtension(String theLoggerName, Level theLevel) {
- this((Logger) LoggerFactory.getLogger(theLoggerName), theLevel);
+ super(theLoggerName, theLevel);
  }
 
  /**
@@ -92,46 +84,19 @@ public LogbackCaptureTestExtension(String theLoggerName, Level theLevel) {
  */
  public java.util.List<ILoggingEvent> getLogEvents() {
  // copy to avoid concurrent mod errors
- return new ArrayList<>(myListAppender.list);
+ return new ArrayList<>(getAppender().list);
  }
 
  /** Clear accumulated log events. */
  public void clearEvents() {
- myListAppender.list.clear();
- }
-
- public ListAppender<ILoggingEvent> getAppender() {
- return myListAppender;
- }
-
- @Override
- public void beforeEach(ExtensionContext context) throws Exception {
- setUp();
- }
-
- /**
- * Guts of beforeEach exposed for manual lifecycle.
- */
- public void setUp() {
- myListAppender = new ListAppender<>();
- myListAppender.start();
- myLogger.addAppender(myListAppender);
- if (myLevel != null) {
- mySavedLevel = myLogger.getLevel();
- myLogger.setLevel(myLevel);
- }
+ getAppender().list.clear();
  }
 
  @Override
- public void afterEach(ExtensionContext context) throws Exception {
- myLogger.detachAppender(myListAppender);
- myListAppender.stop();
- if (myLevel != null) {
- myLogger.setLevel(mySavedLevel);
- }
+ ListAppender<ILoggingEvent> buildAppender() {
+ return new ListAppender<>();
  }
 
-
  public List<ILoggingEvent> filterLoggingEventsWithMessageEqualTo(String theMessageText){
  return filterLoggingEventsWithPredicate(loggingEvent -> loggingEvent.getFormattedMessage().equals(theMessageText));
  }

hapi-fhir-test-utilities/src/test/java/ca/uhn/test/util/LogContentsTestExtentionTest.java

@@ -0,0 +1,30 @@
+package ca.uhn.test.util;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.containsString;
+
+class LogContentsTestExtentionTest {
+ private static final Logger ourLog = LoggerFactory.getLogger(LogContentsTestExtentionTest.class);
+ @RegisterExtension
+ LogContentsTestExtention myExtention = new LogContentsTestExtention((ch.qos.logback.classic.Logger) ourLog);
+
+ @Test
+ void testExtensionCapturesMessage() {
+ ourLog.info("Hello hello");
+
+ assertThat(myExtention.getLogOutput(), containsString("Hello hello"));
+ }
+
+ @Test
+ void testExtensionCapturesStackTraceAndExceptionMessage() {
+ ourLog.info("Hello hello", new RuntimeException("exception message"));
+
+ assertThat(myExtention.getLogOutput(), containsString("exception message"));
+ assertThat(myExtention.getLogOutput(), containsString("testExtensionCapturesStackTraceAndExceptionMessage"));
+ }
+}