introduced QueryStringContributor component interface

... the idea is to allow nexus plugins contribute additional
query string paramaters.

Signed-off-by: Igor Fedorenko <igor@ifedorenko.com>

nexus/nexus-proxy/src/main/java/org/sonatype/nexus/proxy/storage/remote/http/QueryStringBuilder.java

@@ -0,0 +1,65 @@
+/**
+ * Sonatype Nexus (TM) Open Source Version
+ * Copyright (c) 2007-2012 Sonatype, Inc.
+ * All rights reserved. Includes the third-party code listed at http://links.sonatype.com/products/nexus/oss/attributions.
+ *
+ * This program and the accompanying materials are made available under the terms of the Eclipse Public License Version 1.0,
+ * which accompanies this distribution and is available at http://www.eclipse.org/legal/epl-v10.html.
+ *
+ * Sonatype Nexus (TM) Professional Version is available from Sonatype, Inc. "Sonatype" and "Sonatype Nexus" are trademarks
+ * of Sonatype, Inc. Apache Maven is a trademark of the Apache Software Foundation. M2eclipse is a trademark of the
+ * Eclipse Foundation. All other trademarks are the property of their respective owners.
+ */
+package org.sonatype.nexus.proxy.storage.remote.http;
+
+import java.util.List;
+
+import javax.inject.Inject;
+import javax.inject.Named;
+import javax.inject.Singleton;
+
+import org.codehaus.plexus.util.StringUtils;
+import org.sonatype.nexus.proxy.repository.ProxyRepository;
+import org.sonatype.nexus.proxy.storage.remote.RemoteStorageContext;
+
+@Named
+@Singleton
+public class QueryStringBuilder
+{
+    private final List<QueryStringContributor> queryParameterContributors;
+
+    @Inject
+    public QueryStringBuilder( List<QueryStringContributor> queryParameterContributors )
+    {
+        this.queryParameterContributors = queryParameterContributors;
+    }
+
+    public String getQueryString( RemoteStorageContext ctx, ProxyRepository repository )
+    {
+        final StringBuilder result = new StringBuilder();
+
+        final String configuredQueryString = ctx.getRemoteConnectionSettings().getQueryString();
+
+        if ( StringUtils.isNotBlank( configuredQueryString ) )
+        {
+            result.append( configuredQueryString );
+        }
+
+        for ( QueryStringContributor contributor : queryParameterContributors )
+        {
+            String contributedQueryString = contributor.getQueryString( ctx, repository );
+            if ( StringUtils.isNotBlank( contributedQueryString ) )
+            {
+                if ( StringUtils.isNotBlank( result.toString() ) )
+                {
+                    result.append( '&' );
+                }
+                result.append( contributedQueryString );
+            }
+        }
+
+        final String resultStr = result.toString();
+
+        return StringUtils.isNotBlank( resultStr ) ? resultStr : null;
+    }
+}

nexus/nexus-proxy/src/main/java/org/sonatype/nexus/proxy/storage/remote/http/QueryStringContributor.java

@@ -0,0 +1,32 @@
+/**
+ * Sonatype Nexus (TM) Open Source Version
+ * Copyright (c) 2007-2012 Sonatype, Inc.
+ * All rights reserved. Includes the third-party code listed at http://links.sonatype.com/products/nexus/oss/attributions.
+ *
+ * This program and the accompanying materials are made available under the terms of the Eclipse Public License Version 1.0,
+ * which accompanies this distribution and is available at http://www.eclipse.org/legal/epl-v10.html.
+ *
+ * Sonatype Nexus (TM) Professional Version is available from Sonatype, Inc. "Sonatype" and "Sonatype Nexus" are trademarks
+ * of Sonatype, Inc. Apache Maven is a trademark of the Apache Software Foundation. M2eclipse is a trademark of the
+ * Eclipse Foundation. All other trademarks are the property of their respective owners.
+ */
+package org.sonatype.nexus.proxy.storage.remote.http;
+
+import org.sonatype.nexus.proxy.repository.ProxyRepository;
+import org.sonatype.nexus.proxy.storage.remote.RemoteStorageContext;
+
+/**
+ * Classes implementing this interface are injected into the {@link QueryStringBuilder} and asked for a custom string to
+ * append to the query string. The string will be prepended with either ``&'' or ``?'' as necessary. 
+ * 
+ * @since 2.2
+ */
+public interface QueryStringContributor
+{
+    /**
+     * @param ctx The remote storage settings.
+     * @param repository The proxy repository
+     * @return The string to append to query string
+     */
+    public String getQueryString( RemoteStorageContext ctx, ProxyRepository repository );
+}

nexus/nexus-proxy/src/main/java/org/sonatype/nexus/proxy/storage/remote/httpclient/HttpClientRemoteStorage.java

@@ -56,6 +56,7 @@
 import org.sonatype.nexus.proxy.storage.remote.RemoteItemNotFoundException;
 import org.sonatype.nexus.proxy.storage.remote.RemoteRepositoryStorage;
 import org.sonatype.nexus.proxy.storage.remote.RemoteStorageContext;
+import org.sonatype.nexus.proxy.storage.remote.http.QueryStringBuilder;
 import org.sonatype.nexus.proxy.utils.UserAgentBuilder;
 
 /**
@@ -99,16 +100,19 @@ public class HttpClientRemoteStorage
      */
     private static final boolean CAN_WRITE = true;
 
+    private QueryStringBuilder queryStringBuilder;
+
     // ----------------------------------------------------------------------
     // Constructors
     // ----------------------------------------------------------------------
 
     @Inject
     HttpClientRemoteStorage( final UserAgentBuilder userAgentBuilder,
                              final ApplicationStatusSource applicationStatusSource,
-                             final MimeSupport mimeSupport )
+                             final MimeSupport mimeSupport, QueryStringBuilder queryStringBuilder)
     {
         super( userAgentBuilder, applicationStatusSource, mimeSupport );
+        this.queryStringBuilder = queryStringBuilder;
     }
 
     // ----------------------------------------------------------------------
@@ -573,7 +577,8 @@ private URL appendQueryString( final URL url,
     {
         final RemoteStorageContext ctx = getRemoteStorageContext( repository );
 
-        final String queryString = ctx.getRemoteConnectionSettings().getQueryString();
+        String queryString = queryStringBuilder.getQueryString( ctx, repository );
+
         if ( StringUtils.isNotBlank( queryString ) )
         {
             try

nexus/nexus-proxy/src/test/java/org/sonatype/nexus/proxy/storage/remote/http/QueryStringBuilderTest.java

@@ -0,0 +1,110 @@
+/**
+ * Sonatype Nexus (TM) Open Source Version
+ * Copyright (c) 2007-2012 Sonatype, Inc.
+ * All rights reserved. Includes the third-party code listed at http://links.sonatype.com/products/nexus/oss/attributions.
+ *
+ * This program and the accompanying materials are made available under the terms of the Eclipse Public License Version 1.0,
+ * which accompanies this distribution and is available at http://www.eclipse.org/legal/epl-v10.html.
+ *
+ * Sonatype Nexus (TM) Professional Version is available from Sonatype, Inc. "Sonatype" and "Sonatype Nexus" are trademarks
+ * of Sonatype, Inc. Apache Maven is a trademark of the Apache Software Foundation. M2eclipse is a trademark of the
+ * Eclipse Foundation. All other trademarks are the property of their respective owners.
+ */
+package org.sonatype.nexus.proxy.storage.remote.http;
+
+import java.util.Arrays;
+import java.util.Collections;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.sonatype.nexus.proxy.repository.DefaultRemoteConnectionSettings;
+import org.sonatype.nexus.proxy.repository.ProxyRepository;
+import org.sonatype.nexus.proxy.storage.remote.DefaultRemoteStorageContext;
+import org.sonatype.nexus.proxy.storage.remote.RemoteStorageContext;
+
+public class QueryStringBuilderTest
+{
+    @Test
+    public void testNoQueryString()
+    {
+        QueryStringBuilder subject = new QueryStringBuilder( Collections.<QueryStringContributor> emptyList() );
+        Assert.assertNull( subject.getQueryString( getRemoteStorageContext( null ), null ) );
+    }
+
+    @Test
+    public void testConfiguredStringOnly()
+    {
+        QueryStringBuilder subject = new QueryStringBuilder( Collections.<QueryStringContributor> emptyList() );
+
+        String configuredString = "configuredString";
+
+        Assert.assertEquals( configuredString,
+                             subject.getQueryString( getRemoteStorageContext( configuredString ), null ) );
+    }
+
+    @Test
+    public void testOneContributor()
+    {
+        final String contributedString = "contributedString";
+        QueryStringContributor contributor = new QueryStringContributor()
+        {
+            @Override
+            public String getQueryString( RemoteStorageContext ctx, ProxyRepository repository )
+            {
+                return contributedString;
+            }
+        };
+        QueryStringBuilder subject = new QueryStringBuilder( Collections.singletonList( contributor ) );
+        Assert.assertEquals( contributedString, subject.getQueryString( getRemoteStorageContext( null ), null ) );
+    }
+
+    @Test
+    public void testTwoContributor()
+    {
+        QueryStringContributor contributor1 = new QueryStringContributor()
+        {
+            @Override
+            public String getQueryString( RemoteStorageContext ctx, ProxyRepository repository )
+            {
+                return "contributedString1";
+            }
+        };
+        QueryStringContributor contributor2 = new QueryStringContributor()
+        {
+            @Override
+            public String getQueryString( RemoteStorageContext ctx, ProxyRepository repository )
+            {
+                return "contributedString2";
+            }
+        };
+
+        QueryStringBuilder subject = new QueryStringBuilder( Arrays.asList( contributor1, contributor2 ) );
+        Assert.assertEquals( "contributedString1&contributedString2",
+                             subject.getQueryString( getRemoteStorageContext( null ), null ) );
+    }
+
+    @Test
+    public void testConfiguredStringAndOneContributor()
+    {
+        QueryStringContributor contributor = new QueryStringContributor()
+        {
+            @Override
+            public String getQueryString( RemoteStorageContext ctx, ProxyRepository repository )
+            {
+                return "contributedString";
+            }
+        };
+        QueryStringBuilder subject = new QueryStringBuilder( Collections.singletonList( contributor ) );
+        Assert.assertEquals( "configuredString&contributedString",
+                             subject.getQueryString( getRemoteStorageContext( "configuredString" ), null ) );
+    }
+
+    private DefaultRemoteStorageContext getRemoteStorageContext( String configuredString )
+    {
+        DefaultRemoteConnectionSettings settings = new DefaultRemoteConnectionSettings();
+        settings.setQueryString( configuredString );
+        DefaultRemoteStorageContext ctx = new DefaultRemoteStorageContext( null );
+        ctx.setRemoteConnectionSettings( settings );
+        return ctx;
+    }
+}