ci-build.sh: give hints when the build goes wrong

In particular, people get javadoc errors a lot, which are confusing
because when even a single javadoc error happens, Maven's javadoc plugin
logs every javadoc *error and warning* at error level, resulting in the
dreaded [ERROR] prefix all over all the javadoc output, burying the
actual javadoc errors amongst the typically more plentiful warnings.

You can actually find these errors though, because they are prefixed
with 'error:' rather than 'warning:'. So we now grep them out and
regurgitate them after declaring the build failed, as a helpful hint
to why the failure occurred.

And if no javadoc-specific errors are found, then we grep for common
words indicating error or failure, and regurgitate those instead.

And if none of those keywords are found, we declare failure at helping.

This commit is dedicated to Nicolas Chiaruttini.

Author: ctrueden

ci-build.sh

@@ -19,6 +19,35 @@ checkSuccess() {
 	# Log non-zero exit code.
 	test $1 -eq 0 || echo "==> FAILED: EXIT CODE $1" 1>&2
 
+	if [ $1 -ne 0 -a -f "$2" ]
+	then
+		# The operation failed and a log file was provided.
+		# Do some heuristics, because we like being helpful!
+		javadocErrors=$(grep error: "$2")
+		generalErrors=$(grep -i '\b\(errors\?\|fail\|failures\?\)\b' "$2")
+		if [ "$javadocErrors" ]
+		then
+			echo
+			echo '/----------------------------------------------------------\'
+			echo '| ci-build.sh analysis: I noticed probable javadoc errors: |'
+			echo '\----------------------------------------------------------/'
+			echo "$javadocErrors"
+		elif [ "$generalErrors" ]
+		then
+			echo
+			echo '/-------------------------------------------------------\'
+			echo '| ci-build.sh analysis: I noticed the following errors: |'
+			echo '\-------------------------------------------------------/'
+			echo "$generalErrors"
+		else
+			echo
+			echo '/----------------------------------------------------------------------\'
+			echo '| ci-build.sh analysis: I see no problems in the operation log. Sorry! |'
+			echo '\----------------------------------------------------------------------/'
+			echo
+		fi
+	fi
+
 	# Record the first non-zero exit code.
 	test $success -eq 0 && success=$1
 }
@@ -208,19 +237,19 @@ EOL
 	if [ "$deployOK" -a -f release.properties ]; then
 		echo
 		echo "== Cutting and deploying release version =="
-		mvn $BUILD_ARGS release:perform
-		checkSuccess $?
+		BUILD_ARGS="$BUILD_ARGS release:perform"
 	elif [ "$deployOK" ]; then
 		echo
 		echo "== Building and deploying main branch SNAPSHOT =="
-		mvn -Pdeploy-to-scijava $BUILD_ARGS deploy
-		checkSuccess $?
+		BUILD_ARGS="-Pdeploy-to-scijava $BUILD_ARGS deploy"
 	else
 		echo
 		echo "== Building the artifact locally only =="
-		mvn $BUILD_ARGS install javadoc:javadoc
-		checkSuccess $?
+		BUILD_ARGS="$BUILD_ARGS install javadoc:javadoc"
 	fi
+	# Check the build result.
+	{ mvn $BUILD_ARGS; echo $? > exit-code; } | tee mvn-log
+	checkSuccess "$(cat exit-code)" mvn-log
 
 	# --== POST-BUILD ACTIONS ==--