Build the bookSelection query string when we parse the query.

We have to reuse the query the user give us to generate the
pagination links.
At search result rendering step we don't have access to the query object.
The best place to know which arguments are used to select books
(and so which arguments to keep in the pagination links) is when we
parse the query to select books.

Fix tests (pagination links) with book selector other than "books.id="
(pattern=jazz&books.query.lang=eng)

include/search_renderer.h

@@ -81,9 +81,9 @@ class SearchRenderer
   void setSearchPattern(const std::string& pattern);
 
   /**
-   * Set the book names used to do the search.
+   * Set the querystring used to select books
    */
-  void setSearchBookIds(const std::set<std::string>& bookIds);
+  void setSearchBookQuery(const std::string& bookQuery);
 
   /**
    * Set protocol prefix.
@@ -112,7 +112,7 @@ class SearchRenderer
   zim::SearchResultSet m_srs;
   NameMapper* mp_nameMapper;
   Library* mp_library;
-  std::set<std::string> searchBookIds;
+  std::string searchBookQuery;
   std::string searchPattern;
   std::string protocolPrefix;
   std::string searchProtocolPrefix;

src/search_renderer.cpp

@@ -71,9 +71,9 @@ void SearchRenderer::setSearchPattern(const std::string& pattern)
   searchPattern = pattern;
 }
 
-void SearchRenderer::setSearchBookIds(const std::set<std::string>& bookIds)
+void SearchRenderer::setSearchBookQuery(const std::string& bookQuery)
 {
-  searchBookIds = bookIds;
+  searchBookQuery = bookQuery;
 }
 
 void SearchRenderer::setProtocolPrefix(const std::string& prefix)
@@ -90,15 +90,13 @@ kainjow::mustache::data buildQueryData
 (
   const std::string& searchProtocolPrefix,
   const std::string& pattern,
-  const std::set<std::string>& bookIds
+  const std::string& bookQuery
 ) {
   kainjow::mustache::data query;
   query.set("pattern", kiwix::encodeDiples(pattern));
   std::ostringstream ss;
   ss << searchProtocolPrefix << "?pattern=" << urlEncode(pattern, true);
-  for (auto& bookId: bookIds) {
-    ss << "&books.id="<<urlEncode(bookId, true);
-  }
+  ss << "&" << bookQuery;
   query.set("unpaginatedQuery", ss.str());
   return query;
 }
@@ -199,7 +197,7 @@ std::string SearchRenderer::getHtml()
   kainjow::mustache::data query = buildQueryData(
     searchProtocolPrefix,
     searchPattern,
-    searchBookIds
+    searchBookQuery
   );
 
   std::string template_str = RESOURCE::templates::search_result_html;

src/server/internalServer.cpp

@@ -214,13 +214,15 @@ void checkBookNumber(const Library::BookIdSet& bookIds, size_t limit) {
 
 } // unnamed namespace
 
-Library::BookIdSet InternalServer::selectBooks(const RequestContext& request) const
+std::pair<std::string, Library::BookIdSet> InternalServer::selectBooks(const RequestContext& request) const
 {
   // Try old API
   try {
     auto bookName = request.get_argument("content");
     try {
-      return {mp_nameMapper->getIdForName(bookName)};
+      const auto bookIds = Library::BookIdSet{mp_nameMapper->getIdForName(bookName)};
+      const auto queryString = request.get_query([&](const std::string& key){return key == "content";});
+      return {queryString, bookIds};
     } catch (const std::out_of_range&) {
       throw Error(noSuchBookErrorMsg(bookName));
     }
@@ -236,7 +238,8 @@ Library::BookIdSet InternalServer::selectBooks(const RequestContext& request) co
       throw Error(noValueForArgMsg("books.id"));
     }
     const auto bookIds = Library::BookIdSet(id_vec.begin(), id_vec.end());
-    return bookIds;
+    const auto queryString = request.get_query([&](const std::string& key){return key == "books.id";});
+    return {queryString, bookIds};
   } catch(const std::out_of_range&) {}
 
   // Use the names
@@ -253,7 +256,8 @@ Library::BookIdSet InternalServer::selectBooks(const RequestContext& request) co
         throw Error(noSuchBookErrorMsg(bookName));
       }
     }
-    return bookIds;
+    const auto queryString = request.get_query([&](const std::string& key){return key == "books.name";});
+    return {queryString, bookIds};
   } catch(const std::out_of_range&) {}
 
   // Check for filtering
@@ -263,13 +267,14 @@ Library::BookIdSet InternalServer::selectBooks(const RequestContext& request) co
     throw Error(nonParameterizedMessage("no-book-found"));
   }
   const auto bookIds = Library::BookIdSet(id_vec.begin(), id_vec.end());
-  return bookIds;
+  const auto queryString = request.get_query([&](const std::string& key){return startsWith(key, "books.filter.");});
+  return {queryString, bookIds};
 }
 
 SearchInfo InternalServer::getSearchInfo(const RequestContext& request) const
 {
   auto bookIds = selectBooks(request);
-  checkBookNumber(bookIds, m_multizimSearchLimit);
+  checkBookNumber(bookIds.second, m_multizimSearchLimit);
   auto pattern = request.get_optional_param<std::string>("pattern", "");
   GeoQuery geoQuery;
 
@@ -286,13 +291,14 @@ SearchInfo InternalServer::getSearchInfo(const RequestContext& request) const
     throw Error(nonParameterizedMessage("no-query"));
   }
 
-  return SearchInfo(pattern, geoQuery, bookIds);
+  return SearchInfo(pattern, geoQuery, bookIds.second, bookIds.first);
 }
 
-SearchInfo::SearchInfo(const std::string& pattern, GeoQuery geoQuery, const Library::BookIdSet& bookIds)
+SearchInfo::SearchInfo(const std::string& pattern, GeoQuery geoQuery, const Library::BookIdSet& bookIds, const std::string& bookFilterQuery)
   : pattern(pattern),
     geoQuery(geoQuery),
-    bookIds(bookIds)
+    bookIds(bookIds),
+    bookFilterQuery(bookFilterQuery)
 {}
 
 zim::Query SearchInfo::getZimQuery(bool verbose) const {
@@ -751,7 +757,7 @@ std::unique_ptr<Response> InternalServer::handle_search(const RequestContext& re
     SearchRenderer renderer(search->getResults(start, pageLength), mp_nameMapper, mp_library, start,
                             search->getEstimatedMatches());
     renderer.setSearchPattern(searchInfo.pattern);
-    renderer.setSearchBookIds(bookIds);
+    renderer.setSearchBookQuery(searchInfo.bookFilterQuery);
     renderer.setProtocolPrefix(m_root + "/");
     renderer.setSearchProtocolPrefix(m_root + "/search");
     renderer.setPageLength(pageLength);

src/server/internalServer.h

@@ -68,7 +68,7 @@ struct GeoQuery {
 
 class SearchInfo {
   public:
-    SearchInfo(const std::string& pattern, GeoQuery geoQuery, const Library::BookIdSet& bookIds);
+    SearchInfo(const std::string& pattern, GeoQuery geoQuery, const Library::BookIdSet& bookIds, const std::string& bookFilterString);
 
     zim::Query getZimQuery(bool verbose) const;
     const Library::BookIdSet& getBookIds() const { return bookIds; }
@@ -83,6 +83,7 @@ class SearchInfo {
     std::string pattern;
     GeoQuery geoQuery;
     Library::BookIdSet bookIds;
+    std::string bookFilterQuery;
 };
 
 
@@ -149,7 +150,7 @@ class InternalServer {
 
     bool etag_not_needed(const RequestContext& r) const;
     ETag get_matching_if_none_match_etag(const RequestContext& request) const;
-    Library::BookIdSet selectBooks(const RequestContext& r) const;
+    std::pair<std::string, Library::BookIdSet> selectBooks(const RequestContext& r) const;
     SearchInfo getSearchInfo(const RequestContext& r) const;
 
   private: // data