= core: modified version of GlobPathFilter and improve GlobPahFilterSpec

3 files changed, 112 insertions, 46 deletions

diff --git a/kamon-core/src/main/java/kamon/util/GlobPathFilter.java b/kamon-core/src/main/java/kamon/util/GlobPathFilter.java
new file mode 100644
index 00000000..0c7b999c
--- /dev/null
+++ b/kamon-core/src/main/java/kamon/util/GlobPathFilter.java
@@ -0,0 +1,110 @@
+/*
+ * =========================================================================================
+ * Copyright  2013-2014 the kamon project <http://kamon.io/>
+ *
+ * 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 kamon.util;
+
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * Default implementation of PathFilter.  Uses glob based includes and excludes to determine whether to export.
+ *
+ * @author John E. Bailey
+ * @author <a href="mailto:david.lloyd@redhat.com">David M. Lloyd</a>
+ */
+public final class GlobPathFilter  {
+    private static final Pattern GLOB_PATTERN = Pattern.compile("(\\*\\*?)|(\\?)|(\\\\.)|(/+)|([^*?]+)");
+
+    private final String glob;
+    private final Pattern pattern;
+
+    /**
+     * Construct a new instance.
+     *
+     * @param glob the path glob to match
+     */
+    public GlobPathFilter(final String glob) {
+        pattern = getGlobPattern(glob);
+        this.glob = glob;
+    }
+
+    /**
+     * Determine whether a path should be accepted.
+     *
+     * @param path the path to check
+     * @return true if the path should be accepted, false if not
+     */
+    public boolean accept(final String path) {
+        return pattern.matcher(path).matches();
+    }
+
+    /**
+     * Get a regular expression pattern which accept any path names which match the given glob.  The glob patterns
+     * function similarly to {@code ant} file patterns.  Valid metacharacters in the glob pattern include:
+     * <ul>
+     * <li><code>"\"</code> - escape the next character (treat it literally, even if it is itself a recognized metacharacter)</li>
+     * <li><code>"?"</code> - match any non-slash character</li>
+     * <li><code>"*"</code> - match zero or more non-slash characters</li>
+     * <li><code>"**"</code> - match zero or more characters, including slashes</li>
+     * <li><code>"/"</code> - match one or more slash characters.  Consecutive {@code /} characters are collapsed down into one.</li>
+     * </ul>
+     * In addition, any glob pattern matches all subdirectories thereof.  A glob pattern ending in {@code /} is equivalent
+     * to a glob pattern ending in <code>/**</code> in that the named directory is not itself included in the glob.
+     * <p/>
+     * <b>See also:</b> <a href="http://ant.apache.org/manual/dirtasks.html#patterns">"Patterns" in the Ant Manual</a>
+     *
+     * @param glob the glob to match
+     *
+     * @return the pattern
+     */
+    private static Pattern getGlobPattern(final String glob) {
+        StringBuilder patternBuilder = new StringBuilder();
+        final Matcher m = GLOB_PATTERN.matcher(glob);
+        boolean lastWasSlash = false;
+        while (m.find()) {
+            lastWasSlash = false;
+            String grp;
+            if ((grp = m.group(1)) != null) {
+                // match a * or **
+                if (grp.length() == 2) {
+                    // it's a *workers are able to process multiple metrics*
+                    patternBuilder.append(".*");
+                } else {
+                    // it's a *
+                    patternBuilder.append("[^/]*");
+                }
+            } else if ((grp = m.group(2)) != null) {
+                // match a '?' glob pattern; any non-slash character
+                patternBuilder.append("[^/]");
+            } else if ((grp = m.group(3)) != null) {
+                // backslash-escaped value
+                patternBuilder.append(Pattern.quote(m.group().substring(1)));
+            } else if ((grp = m.group(4)) != null) {
+                // match any number of / chars
+                patternBuilder.append("/+");
+                lastWasSlash = true;
+            } else {
+                // some other string
+                patternBuilder.append(Pattern.quote(m.group()));
+            }
+        }
+        if (lastWasSlash) {
+            // ends in /, append **
+            patternBuilder.append(".*");
+        }
+        return Pattern.compile(patternBuilder.toString());
+    }
+}
\ No newline at end of file
diff --git a/kamon-core/src/main/scala/kamon/metric/MetricsExtension.scala b/kamon-core/src/main/scala/kamon/metric/MetricsExtension.scala
index 88802d52..ed55ab06 100644
--- a/kamon-core/src/main/scala/kamon/metric/MetricsExtension.scala
+++ b/kamon-core/src/main/scala/kamon/metric/MetricsExtension.scala
@@ -88,8 +88,8 @@ class MetricsExtension(system: ExtendedActorSystem) extends Kamon.Extension {
         val key = entry.getKey
         val keyBasedConfig = entry.getValue.atKey(key)
 
-        val includes = keyBasedConfig.getStringList(s"$key.includes").asScala.map(inc ⇒ GlobPathFilter(inc)).toList
-        val excludes = keyBasedConfig.getStringList(s"$key.excludes").asScala.map(exc ⇒ GlobPathFilter(exc)).toList
+        val includes = keyBasedConfig.getStringList(s"$key.includes").asScala.map(inc ⇒ new GlobPathFilter(inc)).toList
+        val excludes = keyBasedConfig.getStringList(s"$key.excludes").asScala.map(exc ⇒ new GlobPathFilter(exc)).toList
 
         (key, MetricGroupFilter(includes, excludes))
       }
diff --git a/kamon-core/src/main/scala/kamon/util/GlobPathFilter.scala b/kamon-core/src/main/scala/kamon/util/GlobPathFilter.scala
deleted file mode 100644
index a980773f..00000000
--- a/kamon-core/src/main/scala/kamon/util/GlobPathFilter.scala
+++ /dev/null
@@ -1,44 +0,0 @@
-/*
- * =========================================================================================
- * Copyright © 2013-2014 the kamon project <http://kamon.io/>
- *
- * 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 kamon.util
-
-import scala.util.matching.Regex
-
-class GlobPathFilter(glob: String) {
-
-  val regex = globAsRegex(glob)
-
-  def accept(path: String): Boolean = path.matches(regex.toString())
-
-  private def globAsRegex(glob: String): Regex = {
-    val regexStr = new StringBuilder('^')
-
-    glob.foreach {
-      case '.' ⇒ regexStr append """\."""
-      case '*' ⇒ regexStr append """[^/]*"""
-      case '?' ⇒ regexStr append """."""
-      case ch  ⇒ regexStr append ch
-    }
-    regexStr append """/?$"""
-
-    new Regex(regexStr.toString())
-  }
-}
-
-object GlobPathFilter {
-  def apply(glob: String): GlobPathFilter = new GlobPathFilter(glob)
-}