DBZ-3943 Add ConfigDef unit tests to verify all Debezium Field instan…

…ces have a proper documentation/description set;

Also adding missing descriptions.

debezium-connector-mongodb/src/main/java/io/debezium/connector/mongodb/MongoDbConnectorConfig.java

@@ -413,7 +413,11 @@ public static SnapshotMode parse(String value, String defaultValue) {
             .withWidth(Width.LONG)
             .withImportance(Importance.MEDIUM)
             .withValidation(MongoDbConnectorConfig::validateFieldRenamesList)
-            .withDescription("");
+            .withDescription("A comma-separated list of the fully-qualified replacements of fields that" +
+                    " should be used to rename fields in change event message values. Fully-qualified replacements" +
+                    " for fields are of the form databaseName.collectionName.fieldName.nestedFieldName:newNestedFieldName," +
+                    " where databaseName and collectionName may contain the wildcard (*) which matches any characters," +
+                    " the colon character (:) is used to determine rename mapping of field.");
 
     public static final Field SNAPSHOT_MODE = Field.create("snapshot.mode")
             .withDisplayName("Snapshot mode")

debezium-connector-mongodb/src/test/java/io/debezium/connector/mongodb/MongoDbConnectorConfigDefTest.java

@@ -0,0 +1,15 @@
+/*
+ * Copyright Debezium Authors.
+ *
+ * Licensed under the Apache Software License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package io.debezium.connector.mongodb;
+
+import io.debezium.config.ConfigDefinitionMetadataTest;
+
+public class MongoDbConnectorConfigDefTest extends ConfigDefinitionMetadataTest {
+
+    public MongoDbConnectorConfigDefTest() {
+        super(new MongoDbConnector());
+    }
+}

debezium-connector-mongodb/src/test/java/io/debezium/connector/mongodb/MongoDbTransformationConfigDefTest.java

@@ -0,0 +1,16 @@
+/*
+ * Copyright Debezium Authors.
+ *
+ * Licensed under the Apache Software License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package io.debezium.connector.mongodb;
+
+import io.debezium.config.TransformationConfigDefinitionMetadataTest;
+import io.debezium.connector.mongodb.transforms.ExtractNewDocumentState;
+
+public class MongoDbTransformationConfigDefTest extends TransformationConfigDefinitionMetadataTest {
+
+    public MongoDbTransformationConfigDefTest() {
+        super(new ExtractNewDocumentState<>());
+    }
+}

debezium-connector-mysql/src/test/java/io/debezium/connector/mysql/MySqlConnectorConfigDefTest.java

@@ -0,0 +1,15 @@
+/*
+ * Copyright Debezium Authors.
+ *
+ * Licensed under the Apache Software License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package io.debezium.connector.mysql;
+
+import io.debezium.config.ConfigDefinitionMetadataTest;
+
+public class MySqlConnectorConfigDefTest extends ConfigDefinitionMetadataTest {
+
+    public MySqlConnectorConfigDefTest() {
+        super(new MySqlConnector());
+    }
+}

debezium-connector-oracle/src/main/java/io/debezium/connector/oracle/OracleConnectorConfig.java

@@ -285,7 +285,13 @@ public class OracleConnectorConfig extends HistorizedRelationalDatabaseConnector
     public static final Field LOG_MINING_BUFFER_TYPE = Field.create("log.mining.buffer.type")
             .withDisplayName("Controls which buffer type implementation to be used")
             .withEnum(LogMiningBufferType.class, LogMiningBufferType.MEMORY)
-            .withImportance(Importance.LOW);
+            .withImportance(Importance.LOW)
+            .withDescription("The buffer type controls how the connector manages buffering transaction data." + System.lineSeparator() +
+                    System.lineSeparator() +
+                    "memory - Uses the JVM process' heap to buffer all transaction data." + System.lineSeparator() +
+                    System.lineSeparator() +
+                    "infinispan - This option uses an embedded Infinispan cache to buffer transaction data and persist it to disk." +
+                    " Use the log.mining.buffer.location property to define the location for storing cache files.");
 
     public static final Field LOG_MINING_BUFFER_LOCATION = Field.create("log.mining.buffer.location")
             .withDisplayName("Location where Infinispan stores buffer caches")

debezium-connector-oracle/src/test/java/io/debezium/connector/oracle/OracleConnectorConfigDefTest.java

@@ -0,0 +1,15 @@
+/*
+ * Copyright Debezium Authors.
+ *
+ * Licensed under the Apache Software License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package io.debezium.connector.oracle;
+
+import io.debezium.config.ConfigDefinitionMetadataTest;
+
+public class OracleConnectorConfigDefTest extends ConfigDefinitionMetadataTest {
+
+    public OracleConnectorConfigDefTest() {
+        super(new OracleConnector());
+    }
+}

debezium-connector-postgres/src/test/java/io/debezium/connector/postgresql/PostgresConnectorConfigDefTest.java

@@ -0,0 +1,15 @@
+/*
+ * Copyright Debezium Authors.
+ *
+ * Licensed under the Apache Software License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package io.debezium.connector.postgresql;
+
+import io.debezium.config.ConfigDefinitionMetadataTest;
+
+public class PostgresConnectorConfigDefTest extends ConfigDefinitionMetadataTest {
+
+    public PostgresConnectorConfigDefTest() {
+        super(new PostgresConnector());
+    }
+}

debezium-connector-sqlserver/src/test/java/io/debezium/connector/sqlserver/SqlServerConnectorConfigDefTest.java

@@ -0,0 +1,15 @@
+/*
+ * Copyright Debezium Authors.
+ *
+ * Licensed under the Apache Software License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package io.debezium.connector.sqlserver;
+
+import io.debezium.config.ConfigDefinitionMetadataTest;
+
+public class SqlServerConnectorConfigDefTest extends ConfigDefinitionMetadataTest {
+
+    public SqlServerConnectorConfigDefTest() {
+        super(new SqlServerConnector());
+    }
+}

debezium-core/src/main/java/io/debezium/transforms/ExtractNewRecordStateConfigDefinition.java

@@ -88,10 +88,11 @@ public static DeleteHandling parse(String value, String defaultValue) {
                     + "rewrite - __deleted field is added to records.");
 
     public static final Field ROUTE_BY_FIELD = Field.create("route.by.field")
-            .withDisplayName("The column which determines how the events will be routed, the value will replace the topic name.")
+            .withDisplayName("Route by field name")
             .withType(ConfigDef.Type.STRING)
             .withWidth(ConfigDef.Width.LONG)
             .withImportance(ConfigDef.Importance.LOW)
+            .withDescription("The column which determines how the events will be routed, the value will replace the topic name.")
             .withDefault("");
 
     public static final Field ADD_FIELDS_PREFIX = Field.create("add.fields.prefix")

debezium-core/src/test/java/io/debezium/config/ConfigDefinitionMetadataTest.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright Debezium Authors.
+ *
+ * Licensed under the Apache Software License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package io.debezium.config;
+
+import static org.fest.assertions.Assertions.assertThat;
+
+import java.util.Map.Entry;
+
+import org.apache.kafka.common.config.ConfigDef;
+import org.apache.kafka.common.config.ConfigDef.ConfigKey;
+import org.apache.kafka.connect.source.SourceConnector;
+import org.junit.Test;
+
+/**
+ * Applies basic checks of completeness for the connector-specific configuration metadata.
+ */
+public abstract class ConfigDefinitionMetadataTest {
+
+    private final ConfigDef config;
+
+    protected ConfigDefinitionMetadataTest(SourceConnector connector) {
+        this.config = connector.config();
+    }
+
+    @Test
+    public void allFieldsShouldHaveDescription() {
+        for (Entry<String, ConfigKey> configKey : config.configKeys().entrySet()) {
+            assertThat(configKey.getValue().documentation)
+                    .describedAs("Description of config key \"" + configKey.getKey() + "\"")
+                    .isNotNull()
+                    .isNotEmpty();
+        }
+    }
+}

debezium-core/src/test/java/io/debezium/config/CoreTransformationConfigDefinitionMetadataTest.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright Debezium Authors.
+ *
+ * Licensed under the Apache Software License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package io.debezium.config;
+
+import io.debezium.transforms.ByLogicalTableRouter;
+import io.debezium.transforms.ExtractNewRecordState;
+import io.debezium.transforms.outbox.EventRouter;
+import io.debezium.transforms.tracing.ActivateTracingSpan;
+
+/**
+ * Applies basic checks of completeness of the SMT-specific configuration metadata for the Debezium core SMTs.
+ */
+public class CoreTransformationConfigDefinitionMetadataTest extends TransformationConfigDefinitionMetadataTest {
+
+    public CoreTransformationConfigDefinitionMetadataTest() {
+        super(
+                new ByLogicalTableRouter<>(),
+                new ExtractNewRecordState<>(),
+                new EventRouter<>(),
+                new ActivateTracingSpan<>());
+    }
+}

debezium-core/src/test/java/io/debezium/config/TransformationConfigDefinitionMetadataTest.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright Debezium Authors.
+ *
+ * Licensed under the Apache Software License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package io.debezium.config;
+
+import static org.fest.assertions.Assertions.assertThat;
+
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Map.Entry;
+import java.util.Set;
+
+import org.apache.kafka.common.config.ConfigDef.ConfigKey;
+import org.apache.kafka.connect.transforms.Transformation;
+import org.junit.Test;
+
+/**
+ * Applies basic checks of completeness for the SMT-specific configuration metadata.
+ */
+public abstract class TransformationConfigDefinitionMetadataTest {
+
+    private final Set<Transformation<?>> transforms;
+
+    public TransformationConfigDefinitionMetadataTest(Transformation<?>... transforms) {
+        Set<Transformation<?>> tmp = new HashSet<>();
+        Collections.addAll(tmp, transforms);
+        this.transforms = Collections.unmodifiableSet(tmp);
+    }
+
+    @Test
+    public void allFieldsShouldHaveDescription() {
+        for (Transformation<?> transformation : transforms) {
+            for (Entry<String, ConfigKey> configKey : transformation.config().configKeys().entrySet()) {
+                assertThat(configKey.getValue().documentation)
+                        .describedAs("Description of config key \"" + configKey.getKey() + "\" of transform class " + transformation.getClass().getName())
+                        .isNotNull()
+                        .isNotEmpty();
+            }
+        }
+    }
+}

debezium-scripting/src/test/java/io/debezium/transforms/ScriptingTransformationConfigDefTest.java

@@ -0,0 +1,15 @@
+/*
+ * Copyright Debezium Authors.
+ *
+ * Licensed under the Apache Software License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package io.debezium.transforms;
+
+import io.debezium.config.TransformationConfigDefinitionMetadataTest;
+
+public class ScriptingTransformationConfigDefTest extends TransformationConfigDefinitionMetadataTest {
+
+    public ScriptingTransformationConfigDefTest() {
+        super(new Filter<>(), new ContentBasedRouter<>());
+    }
+}