From: Joakim Erdfelt <joakime@apache.org>
Date: Thu, 12 Apr 2007 20:11:31 +0000 (+0000)
Subject: Creating archiva-policies module
X-Git-Tag: archiva-1.0-alpha-1~113^2~54
X-Git-Url: https://source.dussan.org/?a=commitdiff_plain;h=4a0241c5919acd3fb80076f42d6f77947bc2a5d5;p=archiva.git

Creating archiva-policies module

git-svn-id: https://svn.apache.org/repos/asf/maven/archiva/branches/archiva-jpox-database-refactor@528216 13f79535-47bb-0310-9956-ffa450edef68
---

diff --git a/archiva-base/archiva-policies/pom.xml b/archiva-base/archiva-policies/pom.xml
new file mode 100644
index 000000000..068148950
--- /dev/null
+++ b/archiva-base/archiva-policies/pom.xml
@@ -0,0 +1,63 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Licensed to the Apache Software Foundation (ASF) under one
+  ~ or more contributor license agreements.  See the NOTICE file
+  ~ distributed with this work for additional information
+  ~ regarding copyright ownership.  The ASF licenses this file
+  ~ to you 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.
+  -->
+
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <parent>
+    <groupId>org.apache.maven.archiva</groupId>
+    <artifactId>archiva-base</artifactId>
+    <version>1.0-SNAPSHOT</version>
+  </parent>
+  <modelVersion>4.0.0</modelVersion>
+  <artifactId>archiva-policies</artifactId>
+  <name>Archiva Base :: Policies</name>
+  <dependencies>
+    <dependency>
+      <groupId>org.apache.maven.archiva</groupId>
+      <artifactId>archiva-common</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>commons-lang</groupId>
+      <artifactId>commons-lang</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.codehaus.plexus</groupId>
+      <artifactId>plexus-digest</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>easymock</groupId>
+      <artifactId>easymock</artifactId>
+      <version>1.2_Java1.3</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.codehaus.plexus</groupId>
+      <artifactId>plexus-slf4j-logging</artifactId>
+      <version>1.1-alpha-1-SNAPSHOT</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-log4j12</artifactId>
+      <version>1.2</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+</project>
diff --git a/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/AbstractUpdatePolicy.java b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/AbstractUpdatePolicy.java
new file mode 100644
index 000000000..c9960e186
--- /dev/null
+++ b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/AbstractUpdatePolicy.java
@@ -0,0 +1,173 @@
+package org.apache.maven.archiva.policies;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+import org.apache.commons.lang.StringUtils;
+import org.apache.maven.archiva.common.utils.VersionUtil;
+import org.codehaus.plexus.logging.AbstractLogEnabled;
+
+import java.io.File;
+import java.util.Calendar;
+import java.util.HashSet;
+import java.util.Properties;
+import java.util.Set;
+
+/**
+ * AbstractUpdatePolicy 
+ *
+ * @author <a href="mailto:joakim@erdfelt.com">Joakim Erdfelt</a>
+ * @version $Id$
+ */
+public abstract class AbstractUpdatePolicy
+    extends AbstractLogEnabled
+    implements PreDownloadPolicy
+{
+    /**
+     * The DISABLED policy means that the artifact retrieval isn't even attempted,
+     * let alone updated locally.
+     */
+    public static final String DISABLED = "disabled";
+
+    /**
+     * <p>
+     * The DAILY policy means that the artifact retrieval occurs only if one of
+     * the following conditions are met...
+     * </p>
+     * <ul>
+     *   <li>The local artifact is not present.</li>
+     *   <li>The local artifact has a last modified timestamp older than (now - 1 day).</li>
+     * </ul>
+     */
+    public static final String DAILY = "daily";
+
+    /**
+     * <p>
+     * The HOURLY policy means that the artifact retrieval occurs only if one of
+     * the following conditions are met...
+     * </p>
+     * <ul>
+     *   <li>The local artifact is not present.</li>
+     *   <li>The local artifact has a last modified timestamp older than (now - 1 hour).</li>
+     * </ul>
+     */
+    public static final String HOURLY = "hourly";
+
+    /**
+     * The ONCE policy means that the artifact retrieval occurs only if the
+     * local artifact is not present.  This means that the retreival can only
+     * occur once.
+     */
+    public static final String ONCE = "once";
+
+    private Set validPolicyCodes = new HashSet();
+
+    public AbstractUpdatePolicy()
+    {
+        validPolicyCodes.add( IGNORED );
+        validPolicyCodes.add( DISABLED );
+        validPolicyCodes.add( DAILY );
+        validPolicyCodes.add( HOURLY );
+        validPolicyCodes.add( ONCE );
+    }
+
+    protected abstract boolean isSnapshotPolicy();
+
+    public boolean applyPolicy( String policySetting, Properties request, File localFile )
+    {
+        String version = request.getProperty( "version", "" );
+        boolean isSnapshotVersion = false;
+        
+        if( StringUtils.isNotBlank( version ) )
+        {
+            isSnapshotVersion = VersionUtil.isSnapshot( version );
+        }
+
+        // Test for mismatches.
+        if ( !isSnapshotVersion && isSnapshotPolicy() )
+        {
+            getLogger().debug( "Non-snapshot version detected in during snapshot policy. ignoring policy.");
+            return true;
+        }
+        
+        if ( isSnapshotVersion && !isSnapshotPolicy() )
+        {
+            getLogger().debug( "Snapshot version detected in during release policy. ignoring policy.");
+            return true;
+        }
+
+        if ( !validPolicyCodes.contains( policySetting ) )
+        {
+            // No valid code? false it is then.
+            getLogger().error( "Unknown artifact-update policyCode [" + policySetting + "]" );
+            return false;
+        }
+        
+        if ( IGNORED.equals( policySetting ) )
+        {
+            // Disabled means no.
+            getLogger().debug( "OK to update, policy ignored." );
+            return true;
+        }
+
+        if ( DISABLED.equals( policySetting ) )
+        {
+            // Disabled means no.
+            getLogger().debug( "NO to update, disabled." );
+            return false;
+        }
+
+        if ( !localFile.exists() )
+        {
+            // No file means it's ok.
+            getLogger().debug( "OK to update, local file does not exist." );
+            return true;
+        }
+
+        if ( ONCE.equals( policySetting ) )
+        {
+            // File exists, but policy is once.
+            getLogger().debug( "NO to update, local file exist (and policy is ONCE)." );
+            return false;
+        }
+
+        if ( DAILY.equals( policySetting ) )
+        {
+            Calendar cal = Calendar.getInstance();
+            cal.add( Calendar.DAY_OF_MONTH, -1 );
+            Calendar fileCal = Calendar.getInstance();
+            fileCal.setTimeInMillis( localFile.lastModified() );
+
+            return cal.after( fileCal );
+        }
+
+        if ( HOURLY.equals( policySetting ) )
+        {
+            Calendar cal = Calendar.getInstance();
+            cal.add( Calendar.HOUR, -1 );
+            Calendar fileCal = Calendar.getInstance();
+            fileCal.setTimeInMillis( localFile.lastModified() );
+
+            return cal.after( fileCal );
+        }
+
+        getLogger().error( "Unhandled policyCode [" + policySetting + "]" );
+        return false;
+    }
+}
diff --git a/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/ChecksumPolicy.java b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/ChecksumPolicy.java
new file mode 100644
index 000000000..f297aa700
--- /dev/null
+++ b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/ChecksumPolicy.java
@@ -0,0 +1,239 @@
+package org.apache.maven.archiva.policies;
+
+import org.codehaus.plexus.digest.ChecksumFile;
+import org.codehaus.plexus.digest.Digester;
+import org.codehaus.plexus.digest.DigesterException;
+import org.codehaus.plexus.logging.AbstractLogEnabled;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Properties;
+import java.util.Set;
+
+public class ChecksumPolicy
+    extends AbstractLogEnabled
+    implements PostDownloadPolicy
+{
+    /**
+     * The FAIL policy indicates that if the checksum does not match the
+     * downloaded file, then remove the downloaded artifact, and checksum
+     * files, and fail the transfer to the client side.
+     */
+    public static final String FAIL = "fail";
+
+    /**
+     * The FIX policy indicates that if the checksum does not match the
+     * downloaded file, then fix the checksum file locally, and return
+     * to the client side the corrected checksum.
+     */
+    public static final String FIX = "fix";
+
+    /**
+     * The IGNORE policy indicates that the checksum is never tested
+     * and even bad downloads and checksum files are left in place
+     * on the local repository.
+     */
+    public static final String IGNORED = "ignored";
+
+    /**
+     * @plexus.requirement role-hint="sha1"
+     */
+    private Digester digestSha1;
+
+    /**
+     * @plexus.requirement role-hint="md5"
+     */
+    private Digester digestMd5;
+
+    /**
+     * @plexus.requirement
+     */
+    private ChecksumFile checksumFile;
+
+    private Set validPolicyCodes = new HashSet();
+
+    public ChecksumPolicy()
+    {
+        validPolicyCodes.add( FAIL );
+        validPolicyCodes.add( FIX );
+        validPolicyCodes.add( IGNORED );
+    }
+
+    public boolean applyPolicy( String policySetting, Properties request, File localFile )
+    {
+        if ( !validPolicyCodes.contains( policySetting ) )
+        {
+            // No valid code? false it is then.
+            getLogger().error( "Unknown checksum policyCode [" + policySetting + "]" );
+            return false;
+        }
+
+        if ( IGNORED.equals( policySetting ) )
+        {
+            // Ignore.
+            return true;
+        }
+
+        if ( !localFile.exists() )
+        {
+            // Local File does not exist.
+            getLogger().debug( "Local file " + localFile.getAbsolutePath() + " does not exist." );
+            return false;
+        }
+
+        File sha1File = new File( localFile.getAbsolutePath() + ".sha1" );
+        File md5File = new File( localFile.getAbsolutePath() + ".md5" );
+
+        if ( FAIL.equals( policySetting ) )
+        {
+            if ( !sha1File.exists() && !md5File.exists() )
+            {
+                getLogger().error( "File " + localFile.getAbsolutePath() + " has no checksum files (sha1 or md5)." );
+                localFile.delete();
+                return false;
+            }
+
+            // Test for sha1 first, then md5
+
+            if ( sha1File.exists() )
+            {
+                try
+                {
+                    return checksumFile.isValidChecksum( sha1File );
+                }
+                catch ( FileNotFoundException e )
+                {
+                    getLogger().warn( "Unable to find sha1 file: " + sha1File.getAbsolutePath(), e );
+                    return false;
+                }
+                catch ( DigesterException e )
+                {
+                    getLogger().warn( "Unable to process sha1 file: " + sha1File.getAbsolutePath(), e );
+                    return false;
+                }
+                catch ( IOException e )
+                {
+                    getLogger().warn( "Unable to process sha1 file: " + sha1File.getAbsolutePath(), e );
+                    return false;
+                }
+            }
+
+            if ( md5File.exists() )
+            {
+                try
+                {
+                    return checksumFile.isValidChecksum( md5File );
+                }
+                catch ( FileNotFoundException e )
+                {
+                    getLogger().warn( "Unable to find md5 file: " + md5File.getAbsolutePath(), e );
+                    return false;
+                }
+                catch ( DigesterException e )
+                {
+                    getLogger().warn( "Unable to process md5 file: " + md5File.getAbsolutePath(), e );
+                    return false;
+                }
+                catch ( IOException e )
+                {
+                    getLogger().warn( "Unable to process md5 file: " + md5File.getAbsolutePath(), e );
+                    return false;
+                }
+            }
+        }
+
+        if ( FIX.equals( policySetting ) )
+        {
+            if ( !sha1File.exists() )
+            {
+                try
+                {
+                    checksumFile.createChecksum( localFile, digestSha1 );
+                }
+                catch ( DigesterException e )
+                {
+                    getLogger().warn( "Unable to create sha1 file: " + e.getMessage(), e );
+                    return false;
+                }
+                catch ( IOException e )
+                {
+                    getLogger().warn( "Unable to create sha1 file: " + e.getMessage(), e );
+                    return false;
+                }
+            }
+            else
+            {
+                try
+                {
+                    checksumFile.isValidChecksum( sha1File );
+                }
+                catch ( FileNotFoundException e )
+                {
+                    getLogger().warn( "Unable to find sha1 file: " + sha1File.getAbsolutePath(), e );
+                    return false;
+                }
+                catch ( DigesterException e )
+                {
+                    getLogger().warn( "Unable to process sha1 file: " + sha1File.getAbsolutePath(), e );
+                    return false;
+                }
+                catch ( IOException e )
+                {
+                    getLogger().warn( "Unable to process sha1 file: " + sha1File.getAbsolutePath(), e );
+                    return false;
+                }
+            }
+
+            if ( !md5File.exists() )
+            {
+                try
+                {
+                    checksumFile.createChecksum( localFile, digestMd5 );
+                }
+                catch ( DigesterException e )
+                {
+                    getLogger().warn( "Unable to create md5 file: " + e.getMessage(), e );
+                    return false;
+                }
+                catch ( IOException e )
+                {
+                    getLogger().warn( "Unable to create md5 file: " + e.getMessage(), e );
+                    return false;
+                }
+            }
+            else
+            {
+                try
+                {
+                    return checksumFile.isValidChecksum( md5File );
+                }
+                catch ( FileNotFoundException e )
+                {
+                    getLogger().warn( "Unable to find md5 file: " + md5File.getAbsolutePath(), e );
+                    return false;
+                }
+                catch ( DigesterException e )
+                {
+                    getLogger().warn( "Unable to process md5 file: " + md5File.getAbsolutePath(), e );
+                    return false;
+                }
+                catch ( IOException e )
+                {
+                    getLogger().warn( "Unable to process md5 file: " + md5File.getAbsolutePath(), e );
+                    return false;
+                }
+            }
+        }
+
+        getLogger().error( "Unhandled policyCode [" + policySetting + "]" );
+        return false;
+    }
+
+    public String getDefaultPolicySetting()
+    {
+        return FIX;
+    }
+
+}
diff --git a/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/DownloadPolicy.java b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/DownloadPolicy.java
new file mode 100644
index 000000000..36f283705
--- /dev/null
+++ b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/DownloadPolicy.java
@@ -0,0 +1,55 @@
+package org.apache.maven.archiva.policies;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+import java.io.File;
+import java.util.Properties;
+
+/**
+ * DownloadPolicy 
+ *
+ * @author <a href="mailto:joakim@erdfelt.com">Joakim Erdfelt</a>
+ * @version $Id$
+ */
+public interface DownloadPolicy
+{
+    /**
+     * The IGNORED policy means that the policy is ignored.
+     */
+    public static final String IGNORED = "ignored";
+    
+    /**
+     * Get the default policy setting.
+     * 
+     * @return the default policy setting.
+     */
+    public String getDefaultPolicySetting();
+
+    /**
+     * Apply the download policy.
+     * 
+     * @param policySetting the policy setting.
+     * @param request the list of request properties that the policy might use.
+     * @param localFile
+     * 
+     * @return true if the policy passes.
+     */
+    public boolean applyPolicy( String policySetting, Properties request, File localFile );
+}
diff --git a/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/PostDownloadPolicy.java b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/PostDownloadPolicy.java
new file mode 100644
index 000000000..ff836f10d
--- /dev/null
+++ b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/PostDownloadPolicy.java
@@ -0,0 +1,48 @@
+package org.apache.maven.archiva.policies;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+
+import java.io.File;
+import java.util.Properties;
+
+/**
+ * Policy to apply after the download has completed, but before the
+ * resource is made available to the calling client. 
+ *
+ * @author <a href="mailto:joakim@erdfelt.com">Joakim Erdfelt</a>
+ * @version $Id$
+ */
+public interface PostDownloadPolicy extends DownloadPolicy
+{
+    /**
+     * Apply the download policy.
+     * 
+     * A true result allows the download to succeed.  false indicates that the 
+     * download is a failure.
+     * 
+     * @param policySetting the policy setting.
+     * @param request the list of request properties that the policy might use.
+     * @param localFile the local file that this policy affects
+     * 
+     * @return true if the policy passes. false if not.
+     */
+    public boolean applyPolicy( String policySetting, Properties request, File localFile );
+}
diff --git a/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/PreDownloadPolicy.java b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/PreDownloadPolicy.java
new file mode 100644
index 000000000..3d8532f05
--- /dev/null
+++ b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/PreDownloadPolicy.java
@@ -0,0 +1,47 @@
+package org.apache.maven.archiva.policies;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+
+import java.io.File;
+import java.util.Properties;
+
+/**
+ * Policy to apply before the download is attempted.
+ *
+ * @author <a href="mailto:joakim@erdfelt.com">Joakim Erdfelt</a>
+ * @version $Id$
+ */
+public interface PreDownloadPolicy extends DownloadPolicy
+{
+    /**
+     * Apply the download policy.
+     * 
+     * A true result lets the download occur.  A false result prevents the download
+     * from occuring. 
+     * 
+     * @param policySetting the policy setting.
+     * @param request the list of request properties that the policy might use.
+     * @param localFile the local file that this policy affects
+     * 
+     * @return true if the policy passes. false if not.
+     */
+    public boolean applyPolicy( String policySetting, Properties request, File localFile );
+}
diff --git a/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/ReleasesPolicy.java b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/ReleasesPolicy.java
new file mode 100644
index 000000000..9c9bc2daa
--- /dev/null
+++ b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/ReleasesPolicy.java
@@ -0,0 +1,45 @@
+package org.apache.maven.archiva.policies;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+
+/**
+ * {@link PreDownloadPolicy} to apply for released versions.
+ *
+ * @author <a href="mailto:joakim@erdfelt.com">Joakim Erdfelt</a>
+ * @version $Id$
+ * 
+ * @plexus.component role="org.apache.maven.archiva.policies.download.PreDownloadPolicy"
+ *                   role-hint="releases"
+ */
+public class ReleasesPolicy
+    extends AbstractUpdatePolicy
+    implements PreDownloadPolicy
+{
+    public String getDefaultPolicySetting()
+    {
+        return AbstractUpdatePolicy.IGNORED;
+    }
+
+    protected boolean isSnapshotPolicy()
+    {
+        return false;
+    }
+}
diff --git a/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/SnapshotsPolicy.java b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/SnapshotsPolicy.java
new file mode 100644
index 000000000..d786275ed
--- /dev/null
+++ b/archiva-base/archiva-policies/src/main/java/org/apache/maven/archiva/policies/SnapshotsPolicy.java
@@ -0,0 +1,45 @@
+package org.apache.maven.archiva.policies;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+
+/**
+ * {@link PreDownloadPolicy} to apply for snapshot versions. 
+ *
+ * @author <a href="mailto:joakim@erdfelt.com">Joakim Erdfelt</a>
+ * @version $Id$
+ * 
+ * @plexus.component role="org.apache.maven.archiva.policies.download.PreDownloadPolicy"
+ *                   role-hint="releases"
+ */
+public class SnapshotsPolicy
+    extends AbstractUpdatePolicy
+    implements PreDownloadPolicy
+{
+    public String getDefaultPolicySetting()
+    {
+        return AbstractUpdatePolicy.IGNORED;
+    }
+
+    protected boolean isSnapshotPolicy()
+    {
+        return true;
+    }
+}