liquibase: java.lang.NullPointerException during DIFF operation

Liquibase Version

Starting Liquibase at 14:54:49 (version 4.2.2 #36 built at 2020-12-09 20:07+0000)
Liquibase Version: 4.2.2
Liquibase Community 4.2.2 by Datical
Running Java under /usr/lib/jvm/java-11-openjdk-amd64 (Version 11.0.9.1)

Command to generate snapshot

liquibase \
        --driver=org.postgresql.Driver \
        --classpath=postgresql-42.2.18.jar \
        --url="jdbc:postgresql://$SQL_IP/$SQL_DATABASE" \
        --username="$SQL_USERNAME" \
        --password="$SQL_PASSWORD" \
        --changeLogFile="$CHANGELOG_MASTER_FILE" \
        --liquibaseSchemaName=$SQL_LIQUIBASE_SCHEMA \
        --defaultSchemaName=$SQL_APPLICATION_SCHEMA \
        --contexts=$ENVIRONMENT \
        --outputFile="$STATUS_LOG_FOLDER/snapshot.after.json" \
        snapshot \
        --snapshotFormat=json

Command to generate diff

liquibase \
        --driver=org.postgresql.Driver \
        --classpath=postgresql-42.2.18.jar \
        --url="offline:postgresql?snapshot=$STATUS_LOG_FOLDER/snapshot.before.json" \
        --referenceUrl="jdbc:postgresql://$SQL_IP/$SQL_DATABASE" \
        --referenceusername="$SQL_USERNAME" \
        --referencepassword="$SQL_PASSWORD" \
        --referenceDefaultSchemaName=$SQL_APPLICATION_SCHEMA \
        --liquibaseSchemaName=$SQL_LIQUIBASE_SCHEMA \
        --contexts=$ENVIRONMENT \
        --outputFile="$STATUS_LOG_FOLDER/diff.txt" \
        diff

Thsi is the error I’m getting when launching DIFF command

[2021-01-15 14:53:41] FINE [liquibase.servicelocator] Loaded liquibase.diff.DiffGenerator instance liquibase.diff.core.StandardDiffGenerator
Unexpected error running Liquibase: java.lang.NullPointerException
For more information, please use the --logLevel flag
[2021-01-15 14:53:41] SEVERE [liquibase.integration] Unexpected error running Liquibase: java.lang.NullPointerException
liquibase.exception.LiquibaseException: liquibase.command.CommandExecutionException: java.lang.NullPointerException
        at liquibase.integration.commandline.CommandLineUtils.doDiff(CommandLineUtils.java:173)
        at liquibase.integration.commandline.Main.doMigration(Main.java:1480)
        at liquibase.integration.commandline.Main$1.lambda$run$0(Main.java:361)
        at liquibase.Scope.lambda$child$0(Scope.java:160)
        at liquibase.Scope.child(Scope.java:169)
        at liquibase.Scope.child(Scope.java:159)
        at liquibase.Scope.child(Scope.java:138)
        at liquibase.Scope.child(Scope.java:222)
        at liquibase.Scope.child(Scope.java:226)
        at liquibase.integration.commandline.Main$1.run(Main.java:360)
        at liquibase.integration.commandline.Main$1.run(Main.java:193)
        at liquibase.Scope.child(Scope.java:169)
        at liquibase.Scope.child(Scope.java:145)
        at liquibase.integration.commandline.Main.run(Main.java:193)
        at liquibase.integration.commandline.Main.main(Main.java:156)
Caused by: liquibase.command.CommandExecutionException: java.lang.NullPointerException
        at liquibase.command.AbstractCommand.execute(AbstractCommand.java:24)
        at liquibase.integration.commandline.CommandLineUtils.doDiff(CommandLineUtils.java:171)
        ... 14 more
Caused by: java.lang.NullPointerException
        at liquibase.diff.compare.core.IndexComparator$1.areEqual(IndexComparator.java:123)
        at liquibase.diff.ObjectDifferences.compare(ObjectDifferences.java:70)
        at liquibase.diff.ObjectDifferences.compare(ObjectDifferences.java:50)
        at liquibase.diff.compare.core.IndexComparator.findDifferences(IndexComparator.java:113)
        at liquibase.diff.compare.DatabaseObjectComparatorChain.findDifferences(DatabaseObjectComparatorChain.java:99)
        at liquibase.diff.compare.DatabaseObjectComparatorFactory.findDifferences(DatabaseObjectComparatorFactory.java:166)
        at liquibase.diff.core.StandardDiffGenerator.compareObjectType(StandardDiffGenerator.java:90)
        at liquibase.diff.core.StandardDiffGenerator.compare(StandardDiffGenerator.java:52)
        at liquibase.diff.DiffGeneratorFactory.compare(DiffGeneratorFactory.java:107)
        at liquibase.command.core.DiffCommand.createDiffResult(DiffCommand.java:152)
        at liquibase.command.core.DiffCommand.run(DiffCommand.java:136)
        at liquibase.command.AbstractCommand.execute(AbstractCommand.java:19)
        ... 15 more

Testing Criteria

This needs to be tested against AWS Aurora PostgreSQL 10.11 compatible.

Source Line: IndexComparator.java:123

I added the logLevel=DEBUG as suggested, but besided having the stacktrace I’m not getting additional information.