Grok Compiler: Abort when unable to find definition for rule

Author: retoo

src/main/java/io/thekraken/grok/api/Grok.java

@@ -15,6 +15,8 @@
  *******************************************************************************/
 package io.thekraken.grok.api;
 
+import static java.lang.String.format;
+
 import java.io.BufferedReader;
 import java.io.File;
 import java.io.FileNotFoundException;
@@ -383,14 +385,19 @@ public void compile(String pattern, boolean namedOnly) throws GrokException {
             addPattern(group.get("pattern"), group.get("definition"));
             group.put("name", group.get("name") + "=" + group.get("definition"));
           } catch (GrokException e) {
-            // Log the exeception
+            throw new RuntimeException(e);
           }
         }
         int count = StringUtils.countMatches(namedRegex, "%{" + group.get("name") + "}");
         for (int i = 0; i < count; i++) {
-          String replacement = String.format("(?<name%d>%s)", index, grokPatternDefinition.get(group.get("pattern")));
+          String definitionOfPattern = grokPatternDefinition.get(group.get("pattern"));
+          if (definitionOfPattern == null) {
+              throw new GrokException(format("No definition for key '%s' found, aborting",
+                  group.get("pattern")));
+          }
+          String replacement = String.format("(?<name%d>%s)", index, definitionOfPattern);
           if (namedOnly && group.get("subname") == null) {
-            replacement = String.format("(?:%s)", grokPatternDefinition.get(group.get("pattern")));
+            replacement = String.format("(?:%s)", definitionOfPattern);
           }
           namedRegexCollection.put("name" + index,
               (group.get("subname") != null ? group.get("subname") : group.get("name")));

src/test/java/io/thekraken/grok/api/GrokTest.java

@@ -18,6 +18,12 @@
 import org.junit.Test;
 import org.junit.runners.MethodSorters;
 
+import java.io.BufferedReader;
+import java.io.FileReader;
+import java.util.*;
+
+import static org.hamcrest.CoreMatchers.containsString;
+import static org.junit.Assert.*;
 import io.thekraken.grok.api.exception.GrokException;
 
 
@@ -597,16 +603,43 @@ public void testDisablingAutomaticConversion() throws GrokException {
     @Test
     public void test020_postfix_patterns() throws Throwable {
         final Grok grok = Grok.create("patterns/postfix");
+        grok.addPatternFromFile("patterns/patterns");
         grok.compile("%{POSTFIX_SMTPD}", false);
 
         assertTrue(grok.getPatterns().containsKey("POSTFIX_SMTPD"));
     }
+
     @Test
     public void test021_postfix_patterns_with_named_captures_only() throws Throwable {
         final Grok grok = Grok.create("patterns/postfix");
+        grok.addPatternFromFile("patterns/patterns");
         grok.compile("%{POSTFIX_SMTPD}", true);
 
         assertTrue(grok.getPatterns().containsKey("POSTFIX_SMTPD"));
     }
 
+    @Test
+    public void test022_named_captures_with_missing_definition() throws Throwable {
+        ensureAbortsWithDefinitionMissing("FOO %{BAR}", "%{FOO}", true);
+    }
+
+    @Test
+    public void test023_captures_with_missing_definition() throws Throwable {
+        ensureAbortsWithDefinitionMissing("FOO %{BAR}", "%{FOO:name}", false);
+    }
+
+    @Test
+    public void test024_captures_with_missing_definition() throws Throwable {
+        ensureAbortsWithDefinitionMissing("FOO %{BAR}", "%{FOO}", false);
+    }
+
+    private void ensureAbortsWithDefinitionMissing(String pattern, String compilePattern, boolean namedOnly) {
+        try {
+            final Grok grok = Grok.create(ResourceManager.PATTERNS, pattern);
+            grok.compile(compilePattern, namedOnly);
+            fail("should abort due to missing definition");
+        } catch (GrokException e) {
+            assertThat(e.getMessage(), containsString("No definition for key"));
+        }
+    }
 }