Implement "strict" mode. (#192)

Levels of strictness:

- `PROCESS`: Abort process by throwing an exception.
- `RECORD`: Ignore (skip) record and log an error.
- `EXPRESSION`: Ignore (skip) expression and log a warning.

Introduces `FixProcessException` to differentiate from `FixExecutionException`: The latter indicating potentially data-dependent issues that should be subject to strictness handling, while the former should only refer to static issues with the usage of Fix expressions.

metafix/src/main/java/org/metafacture/metafix/FixExecutionException.java

@@ -18,6 +18,12 @@
 
 import org.metafacture.framework.MetafactureException;
 
+/**
+ * Indicates dynamic (i.e., data-dependent) issues during Fix execution that
+ * should be subject to {@link Metafix.Strictness strictness} handling.
+ *
+ * @see FixProcessException
+ */
 public class FixExecutionException extends MetafactureException {
 
     public FixExecutionException(final String message) {

metafix/src/main/java/org/metafacture/metafix/FixProcessException.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2022 hbz NRW
+ *
+ * Licensed under the Apache License, Version 2.0 the "License";
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.metafacture.metafix;
+
+import org.metafacture.framework.MetafactureException;
+
+/**
+ * Indicates static (i.e., data-independent) issues with the usage of Fix
+ * expressions.
+ *
+ * @see FixExecutionException
+ */
+public class FixProcessException extends MetafactureException {
+
+    public FixProcessException(final String message) {
+        super(message);
+    }
+
+    public FixProcessException(final String message, final Throwable cause) {
+        super(message, cause);
+    }
+
+}

metafix/src/main/java/org/metafacture/metafix/Metafix.java

@@ -45,6 +45,7 @@
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
+import java.util.function.BiConsumer;
 
 /**
  * Transforms a data stream sent via the {@link StreamReceiver} interface. Use
@@ -61,6 +62,8 @@ public class Metafix implements StreamPipe<StreamReceiver>, Maps { // checkstyle
     public static final String VAR_END = "]";
     public static final String VAR_START = "$[";
 
+    public static final Strictness DEFAULT_STRICTNESS = Strictness.PROCESS;
+
     public static final Map<String, String> NO_VARS = Collections.emptyMap();
 
     private static final Logger LOG = LoggerFactory.getLogger(Metafix.class);
@@ -79,6 +82,7 @@ public class Metafix implements StreamPipe<StreamReceiver>, Maps { // checkstyle
     private List<Value> entities = new ArrayList<>();
     private Record currentRecord = new Record();
     private StreamReceiver outputStreamReceiver;
+    private Strictness strictness = DEFAULT_STRICTNESS;
     private String fixFile;
     private String recordIdentifier;
     private int entityCount;
@@ -325,4 +329,58 @@ public String putValue(final String mapName, final String key, final String valu
         return maps.computeIfAbsent(mapName, k -> new HashMap<>()).put(key, value);
     }
 
+    public void setStrictness(final Strictness strictness) {
+        this.strictness = strictness != null ? strictness : DEFAULT_STRICTNESS;
+    }
+
+    public Strictness getStrictness() {
+        return strictness;
+    }
+
+    public enum Strictness {
+
+        /**
+         * Aborts process by throwing an exception.
+         */
+        PROCESS {
+            @Override
+            protected void handleInternal(final FixExecutionException exception, final Record record) {
+                throw exception;
+            }
+        },
+
+        /**
+         * Ignores (skips) record and logs an error.
+         */
+        RECORD {
+            @Override
+            protected void handleInternal(final FixExecutionException exception, final Record record) {
+                log(exception, LOG::error);
+                record.setReject(true); // TODO: Skip remaining expressions?
+            }
+        },
+
+        /**
+         * Ignores (skips) expression and logs a warning.
+         */
+        EXPRESSION {
+            @Override
+            protected void handleInternal(final FixExecutionException exception, final Record record) {
+                log(exception, LOG::warn);
+            }
+        };
+
+        public void handle(final FixExecutionException exception, final Record record) {
+            LOG.debug("Current record: {}", record);
+            handleInternal(exception, record);
+        }
+
+        protected abstract void handleInternal(FixExecutionException exception, Record record);
+
+        protected void log(final FixExecutionException exception, final BiConsumer<String, Throwable> logger) {
+            logger.accept(exception.getMessage(), exception.getCause());
+        }
+
+    }
+
 }

metafix/src/main/java/org/metafacture/metafix/RecordTransformer.java

@@ -98,7 +98,7 @@ else if (e instanceof MethodCall) {
                 processFunction((MethodCall) e, params);
             }
             else {
-                throw new FixExecutionException(executionExceptionMessage(e));
+                throw new FixProcessException(executionExceptionMessage(e));
             }
         });
     }
@@ -173,15 +173,26 @@ private void processExpression(final Expression expression, final Consumer<Strin
     }
 
     private void processFix(final Supplier<String> messageSupplier, final Runnable runnable) {
+        final FixExecutionException exception;
+
         try {
             runnable.run();
+            return;
         }
-        catch (final FixExecutionException e) {
+        catch (final FixProcessException e) {
             throw e; // TODO: Add nesting information?
         }
+        catch (final FixExecutionException e) {
+            exception = e; // TODO: Add nesting information?
+        }
+        catch (final IllegalStateException | NumberFormatException e) {
+            exception = new FixExecutionException(messageSupplier.get(), e);
+        }
         catch (final RuntimeException e) { // checkstyle-disable-line IllegalCatch
-            throw new FixExecutionException(messageSupplier.get(), e);
+            throw new FixProcessException(messageSupplier.get(), e);
         }
+
+        metafix.getStrictness().handle(exception, record);
     }
 
     private String executionExceptionMessage(final Expression expression) {

metafix/src/test/java/org/metafacture/metafix/MetafixLookupTest.java

@@ -159,7 +159,7 @@ public void shouldLookupInSeparateExternalFileMap() {
     public void shouldNotLookupInRelativeExternalFileMapFromInlineScript() {
         final String mapFile = "../maps/test.csv";
 
-        MetafixTestHelpers.assertThrowsCause(IllegalArgumentException.class, "Cannot resolve relative path: " + mapFile, () ->
+        MetafixTestHelpers.assertProcessException(IllegalArgumentException.class, "Cannot resolve relative path: " + mapFile, () ->
             MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                     LOOKUP + " '" + mapFile + "')"
                 ),
@@ -299,7 +299,7 @@ public void shouldNotLookupInUnknownInternalMap() {
 
     @Test
     public void shouldFailLookupInUnknownExternalMap() {
-        MetafixTestHelpers.assertThrowsCause(MorphExecutionException.class, "File not found: testMap.csv", () ->
+        MetafixTestHelpers.assertProcessException(MorphExecutionException.class, "File not found: testMap.csv", () ->
             MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                     LOOKUP + " 'testMap.csv')"
                 ),

metafix/src/test/java/org/metafacture/metafix/MetafixMethodTest.java

@@ -160,7 +160,7 @@ public void shouldCapitalizeStringsInArray() {
 
     @Test
     public void shouldNotCapitalizeArray() {
-        MetafixTestHelpers.assertThrowsCause(IllegalStateException.class, "Expected String, got Array", () ->
+        MetafixTestHelpers.assertExecutionException(IllegalStateException.class, "Expected String, got Array", () ->
             MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                     "capitalize('title')"
                 ),
@@ -431,7 +431,7 @@ public void parseTextMixedGroups() {
 
     @Test
     public void parseTextEscapedGroups() {
-        MetafixTestHelpers.assertThrowsCause(IllegalArgumentException.class, "No group with name <c>", () ->
+        MetafixTestHelpers.assertProcessException(IllegalArgumentException.class, "No group with name <c>", () ->
             MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                     "parse_text(data, '(?<a>.)(.)\\\\(?<c>.\\\\)')"
                 ),
@@ -448,7 +448,7 @@ public void parseTextEscapedGroups() {
 
     @Test
     public void parseTextQuotedGroups() {
-        MetafixTestHelpers.assertThrowsCause(IllegalArgumentException.class, "No group with name <c>", () ->
+        MetafixTestHelpers.assertProcessException(IllegalArgumentException.class, "No group with name <c>", () ->
             MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                     "parse_text(data, '(?<a>.)(.)\\\\Q(?<c>.)\\\\E')"
                 ),
@@ -669,7 +669,7 @@ public void shouldAppendValueInEntireArray() {
     @Test
     // See https://github.com/metafacture/metafacture-fix/issues/100
     public void shouldNotAppendValueToArray() {
-        MetafixTestHelpers.assertThrowsCause(IllegalStateException.class, "Expected String, got Array", () ->
+        MetafixTestHelpers.assertExecutionException(IllegalStateException.class, "Expected String, got Array", () ->
             MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                     "append('animals[]', ' is cool')"
                 ),
@@ -691,7 +691,7 @@ public void shouldNotAppendValueToArray() {
     @Test
     // See https://github.com/metafacture/metafacture-fix/issues/100
     public void shouldNotAppendValueToHash() {
-        MetafixTestHelpers.assertThrowsCause(IllegalStateException.class, "Expected String, got Hash", () ->
+        MetafixTestHelpers.assertExecutionException(IllegalStateException.class, "Expected String, got Hash", () ->
             MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                     "append('animals', ' is cool')"
                 ),
@@ -1126,7 +1126,7 @@ public void shouldPrependValueInArraySubField() {
     @Test
     // See https://github.com/metafacture/metafacture-fix/issues/100
     public void shouldNotPrependValueToArray() {
-        MetafixTestHelpers.assertThrowsCause(IllegalStateException.class, "Expected String, got Array", () ->
+        MetafixTestHelpers.assertExecutionException(IllegalStateException.class, "Expected String, got Array", () ->
             MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                     "prepend('animals[]', 'cool ')"
                 ),
@@ -1592,7 +1592,7 @@ public void shouldSortFieldNumerically() {
 
     @Test
     public void shouldFailToSortNumericallyWithInvalidNumber() {
-        MetafixTestHelpers.assertThrowsCause(NumberFormatException.class, "For input string: \"x\"", () ->
+        MetafixTestHelpers.assertExecutionException(NumberFormatException.class, "For input string: \"x\"", () ->
             MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                     "sort_field(numbers, numeric: 'true')"
                 ),

metafix/src/test/java/org/metafacture/metafix/MetafixRecordTest.java

@@ -1083,7 +1083,7 @@ public void addFieldToObjectByIndexMissing() {
     }
 
     private void assertThrowsOnEmptyRecord(final String index) {
-        MetafixTestHelpers.assertThrowsCause(IllegalArgumentException.class, "Using ref, but can't find: " + index + " in: {}", () -> {
+        MetafixTestHelpers.assertProcessException(IllegalArgumentException.class, "Using ref, but can't find: " + index + " in: {}", () -> {
             MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                     "add_field('animals[]." + index + ".kind','nice')"
                 ),
@@ -2150,7 +2150,7 @@ public void accessArrayByIndex() {
 
     @Test
     public void shouldNotAccessArrayImplicitly() {
-        MetafixTestHelpers.assertThrowsCause(IllegalStateException.class, "Expected String, got Array", () ->
+        MetafixTestHelpers.assertExecutionException(IllegalStateException.class, "Expected String, got Array", () ->
             MetafixTestHelpers.assertFix(streamReceiver, Arrays.asList(
                     "upcase('name')"
                 ),