1 files changed, 140 insertions, 0 deletions
diff --git a/mobile/android/thirdparty/ch/boye/httpclientandroidlib/impl/client/cache/ConditionalRequestBuilder.java b/mobile/android/thirdparty/ch/boye/httpclientandroidlib/impl/client/cache/ConditionalRequestBuilder.java
new file mode 100644
index 000000000..0edc4fb85
--- /dev/null
+++ b/mobile/android/thirdparty/ch/boye/httpclientandroidlib/impl/client/cache/ConditionalRequestBuilder.java
@@ -0,0 +1,140 @@
+/*
+ * ====================================================================
+ * 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.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ *
+ */
+package ch.boye.httpclientandroidlib.impl.client.cache;
+
+import java.util.Map;
+
+import ch.boye.httpclientandroidlib.Header;
+import ch.boye.httpclientandroidlib.HeaderElement;
+import ch.boye.httpclientandroidlib.ProtocolException;
+import ch.boye.httpclientandroidlib.annotation.Immutable;
+import ch.boye.httpclientandroidlib.client.cache.HeaderConstants;
+import ch.boye.httpclientandroidlib.client.cache.HttpCacheEntry;
+import ch.boye.httpclientandroidlib.client.methods.HttpRequestWrapper;
+
+/**
+ * @since 4.1
+ */
+@Immutable
+class ConditionalRequestBuilder {
+
+    /**
+     * When a {@link HttpCacheEntry} is stale but 'might' be used as a response
+     * to an {@link ch.boye.httpclientandroidlib.HttpRequest} we will attempt to revalidate
+     * the entry with the origin.  Build the origin {@link ch.boye.httpclientandroidlib.HttpRequest}
+     * here and return it.
+     *
+     * @param request the original request from the caller
+     * @param cacheEntry the entry that needs to be re-validated
+     * @return the wrapped request
+     * @throws ProtocolException when I am unable to build a new origin request.
+     */
+    public HttpRequestWrapper buildConditionalRequest(final HttpRequestWrapper request, final HttpCacheEntry cacheEntry)
+            throws ProtocolException {
+        final HttpRequestWrapper newRequest = HttpRequestWrapper.wrap(request.getOriginal());
+        newRequest.setHeaders(request.getAllHeaders());
+        final Header eTag = cacheEntry.getFirstHeader(HeaderConstants.ETAG);
+        if (eTag != null) {
+            newRequest.setHeader(HeaderConstants.IF_NONE_MATCH, eTag.getValue());
+        }
+        final Header lastModified = cacheEntry.getFirstHeader(HeaderConstants.LAST_MODIFIED);
+        if (lastModified != null) {
+            newRequest.setHeader(HeaderConstants.IF_MODIFIED_SINCE, lastModified.getValue());
+        }
+        boolean mustRevalidate = false;
+        for(final Header h : cacheEntry.getHeaders(HeaderConstants.CACHE_CONTROL)) {
+            for(final HeaderElement elt : h.getElements()) {
+                if (HeaderConstants.CACHE_CONTROL_MUST_REVALIDATE.equalsIgnoreCase(elt.getName())
+                    || HeaderConstants.CACHE_CONTROL_PROXY_REVALIDATE.equalsIgnoreCase(elt.getName())) {
+                    mustRevalidate = true;
+                    break;
+                }
+            }
+        }
+        if (mustRevalidate) {
+            newRequest.addHeader(HeaderConstants.CACHE_CONTROL, HeaderConstants.CACHE_CONTROL_MAX_AGE + "=0");
+        }
+        return newRequest;
+
+    }
+
+    /**
+     * When a {@link HttpCacheEntry} does not exist for a specific
+     * {@link ch.boye.httpclientandroidlib.HttpRequest} we attempt to see if an existing
+     * {@link HttpCacheEntry} is appropriate by building a conditional
+     * {@link ch.boye.httpclientandroidlib.HttpRequest} using the variants' ETag values.
+     * If no such values exist, the request is unmodified
+     *
+     * @param request the original request from the caller
+     * @param variants
+     * @return the wrapped request
+     */
+    public HttpRequestWrapper buildConditionalRequestFromVariants(final HttpRequestWrapper request,
+            final Map<String, Variant> variants) {
+        final HttpRequestWrapper newRequest = HttpRequestWrapper.wrap(request.getOriginal());
+        newRequest.setHeaders(request.getAllHeaders());
+
+        // we do not support partial content so all etags are used
+        final StringBuilder etags = new StringBuilder();
+        boolean first = true;
+        for(final String etag : variants.keySet()) {
+            if (!first) {
+                etags.append(",");
+            }
+            first = false;
+            etags.append(etag);
+        }
+
+        newRequest.setHeader(HeaderConstants.IF_NONE_MATCH, etags.toString());
+        return newRequest;
+    }
+
+    /**
+     * Returns a request to unconditionally validate a cache entry with
+     * the origin. In certain cases (due to multiple intervening caches)
+     * our cache may actually receive a response to a normal conditional
+     * validation where the Date header is actually older than that of
+     * our current cache entry. In this case, the protocol recommendation
+     * is to retry the validation and force syncup with the origin.
+     * @param request client request we are trying to satisfy
+     * @param entry existing cache entry we are trying to validate
+     * @return an unconditional validation request
+     */
+    public HttpRequestWrapper buildUnconditionalRequest(final HttpRequestWrapper request, final HttpCacheEntry entry) {
+        final HttpRequestWrapper newRequest = HttpRequestWrapper.wrap(request.getOriginal());
+        newRequest.setHeaders(request.getAllHeaders());
+        newRequest.addHeader(HeaderConstants.CACHE_CONTROL,HeaderConstants.CACHE_CONTROL_NO_CACHE);
+        newRequest.addHeader(HeaderConstants.PRAGMA,HeaderConstants.CACHE_CONTROL_NO_CACHE);
+        newRequest.removeHeaders(HeaderConstants.IF_RANGE);
+        newRequest.removeHeaders(HeaderConstants.IF_MATCH);
+        newRequest.removeHeaders(HeaderConstants.IF_NONE_MATCH);
+        newRequest.removeHeaders(HeaderConstants.IF_UNMODIFIED_SINCE);
+        newRequest.removeHeaders(HeaderConstants.IF_MODIFIED_SINCE);
+        return newRequest;
+    }
+
+}