standard delete support

src/main/java/liquibase/ext/neo4j/generator/DeleteGenerator.java

@@ -0,0 +1,32 @@
+package liquibase.ext.neo4j.generator;
+
+import liquibase.change.ChangeMetaData;
+import liquibase.database.Database;
+import liquibase.exception.ValidationErrors;
+import liquibase.sql.Sql;
+import liquibase.sql.UnparsedSql;
+import liquibase.sqlgenerator.SqlGeneratorChain;
+import liquibase.sqlgenerator.core.AbstractSqlGenerator;
+import liquibase.statement.core.DeleteStatement;
+
+public class DeleteGenerator extends AbstractSqlGenerator<DeleteStatement> {
+
+  @Override
+  public ValidationErrors validate(DeleteStatement deleteStatement, Database database,
+                                   SqlGeneratorChain<DeleteStatement> sqlGeneratorChain) {
+    return null;
+  }
+
+  @Override
+  public Sql[] generateSql(DeleteStatement deleteStatement, Database database,
+                           SqlGeneratorChain<DeleteStatement> sqlGeneratorChain) {
+    String label = deleteStatement.getTableName();
+    String cypher = String.format("MATCH (n: %s)%nDELETE n", label);
+    return new Sql[]{new UnparsedSql(cypher)};
+  }
+
+  @Override
+  public int getPriority() {
+    return ChangeMetaData.PRIORITY_DEFAULT;
+  }
+}

src/main/resources/META-INF/services/liquibase.sqlgenerator.SqlGenerator

@@ -0,0 +1 @@
+liquibase.ext.neo4j.generator.DeleteGenerator

src/test/groovy/liquibase/ext/neo4j/Neo4jPluginTest.groovy

@@ -148,6 +148,30 @@ CREATE (:SecretMovie {title: 'Neo4j 4.4 EE: A life story'});
     }
 
 
+    def "run deletes"(){
+        given:
+        queryRunner.run("MERGE (:Person {name: 'Charles', firstName: 'Clarence'})")
+        String[] arguments = [
+                "--url", "jdbc:neo4j:${neo4jContainer.getBoltUrl()}",
+                "--username", "neo4j",
+                "--password", PASSWORD,
+                "--changeLogFile", "classpath:/changelog-delete.xml",
+                "update"
+        ].toArray()
+
+        when:
+        Main.run(arguments)
+
+        then:
+        def rows = queryRunner.getRows("""
+            MATCH (p: Person)
+            RETURN Count(p) = 0 as result
+        """)
+        rows.size() == 1
+        rows[0] == ["result": true]
+    }
+
+
     private static PrintStream mute() {
         new PrintStream(Files.createTempFile("liquibase", "neo4j").toFile())
     }

src/test/resources/changelog-delete.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<databaseChangeLog xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+                   xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
+                   xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-4.1.xsd">
+
+    <changeSet id="delete" author="clarenced">
+        <comment>Deleting a person</comment>
+        <delete tableName="Person" />
+    </changeSet>
+</databaseChangeLog>