[java-opensaml COMMIT] in /trunk/opensaml-saml-impl/src: main/java/org/opensaml/saml/metadata/resolver/impl/RegexRequ...

[noreply at shibboleth.net]

Author: putmanb
Date: Tue Nov 18 16:59:12 2014
New Revision: 4150

URL: http://svn.shibboleth.net/view/java-opensaml?rev=4150&view=rev
Log:
Flesh out the regex request URL builder for dynamic metadata resolver use.

Added:
    trunk/opensaml-saml-impl/src/test/java/org/opensaml/saml/metadata/resolver/impl/RegexRequestURLBuilderTest.java   (with props)
Modified:
    trunk/opensaml-saml-impl/src/main/java/org/opensaml/saml/metadata/resolver/impl/RegexRequestURLBuilder.java

Modified: trunk/opensaml-saml-impl/src/main/java/org/opensaml/saml/metadata/resolver/impl/RegexRequestURLBuilder.java
URL: http://svn.shibboleth.net/view/java-opensaml/trunk/opensaml-saml-impl/src/main/java/org/opensaml/saml/metadata/resolver/impl/RegexRequestURLBuilder.java?rev=4150&r1=4149&r2=4150&view=diff
==============================================================================
--- trunk/opensaml-saml-impl/src/main/java/org/opensaml/saml/metadata/resolver/impl/RegexRequestURLBuilder.java (original)
+++ trunk/opensaml-saml-impl/src/main/java/org/opensaml/saml/metadata/resolver/impl/RegexRequestURLBuilder.java Tue Nov 18 16:59:12 2014
@@ -17,8 +17,14 @@
 
 package org.opensaml.saml.metadata.resolver.impl;
 
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import net.shibboleth.utilities.java.support.annotation.constraint.NotEmpty;
 import net.shibboleth.utilities.java.support.logic.Constraint;
@@ -27,27 +33,97 @@
 import com.google.common.base.Function;
 
 /**
- *
+ * Function which produces a URL by evaluating a supplied regular expression against the entity ID, and applying the
+ * result to a supplied replacement string.
+ * 
+ * <p>
+ * The function uses standard Java regular expression components from the <code>java.util.regex</code> package.
+ * It is therefore helpful to have an understanding of the use of these Java classes.
+ * </p>
+ * 
+ * <p>
+ * The rutime logic is effectively:
+ * <blockquote><pre>
+ * Pattern pattern = Pattern.compile(regex);
+ * Matcher matcher = pattern.matcher(entityID);
+ * if (matcher.matches()) {
+ *   return matcher.replaceAll(replacement);
+ * else {
+ *   return null;
+ * }
+ * </pre></blockquote>
+ * </p>
+ * 
+ * <p>
+ * For supported regular expression syntax see {@link Pattern}. For details on the replacement operation,
+ * see {@link Matcher#replaceAll(String)}.
+ * </p>
+ * 
+ * <p>
+ * It is expected that the typical use case is that the supplied replacement string will be a combination of 
+ * literal text combined with back references to the regular expression match groups, e.g. $1, $2, etc.
+ * </p>
+ * 
+ * <p>
+ * If the regular expression does not match the entity ID, or if there is an error in evaluating the 
+ * regular expression, then null is returned.
+ * </p>
+ * 
  */
 public class RegexRequestURLBuilder implements Function<String, String> {
     
-    private String pattern;
+    /** Logger. */
+    private final Logger log = LoggerFactory.getLogger(RegexRequestURLBuilder.class);
     
+    /** The compiled pattern. */
+    private Pattern pattern;
+    
+    /** The replacement template. */
     private String template;
     
+    /**
+     * Constructor.
+     *
+     * @param regex the regular expression against which to evaluate the entity ID
+     * @param replacement the the replacement template string.
+     */
     public RegexRequestURLBuilder(@Nonnull @NotEmpty final String regex, @Nonnull @NotEmpty final String replacement) {
-        pattern = Constraint.isNotNull(StringSupport.trimOrNull(regex), "Regex was null or empty");
-        template = Constraint.isNotNull(StringSupport.trimOrNull(replacement), "Replacement template was null or empty");
+        String regexTemp = Constraint.isNotNull(StringSupport.trimOrNull(regex), "Regex was null or empty");
+        /*
+        // TODO: Defensively add start and end anchors if not supplied?
+        if (!regexTemp.startsWith("^")) {
+            regexTemp = "^" + regexTemp;
+        }
+        if (!regexTemp.endsWith("$")) {
+            regexTemp = regexTemp + "$";
+        }
+        */
+        pattern = Pattern.compile(regexTemp);
+        
+        template = Constraint.isNotNull(StringSupport.trimOrNull(replacement), 
+                "Replacement template was null or empty");
     }
 
     /** {@inheritDoc} */
     @Nullable public String apply(@Nonnull String entityID) {
         Constraint.isNotNull(entityID, "Entity ID was null");
         
-        //TODO logging, exception handling
-        
-        //TODO not sure if this approach is fundamentally right
-        return entityID.replaceAll(pattern, template);
+        try {
+            Matcher matcher = pattern.matcher(entityID);
+            if (matcher.matches()) {
+                String result = matcher.replaceAll(template);
+                log.debug("Regular expression '{}' matched successfully against entity ID '{}', returning '{}'", 
+                        pattern.pattern(), entityID, result);

[... 14 lines stripped ...]