Add support for Remap rule hit stats

proxy/http/HttpProxyServerMain.cc

@@ -27,6 +27,7 @@
 #include "HttpSessionAccept.h"
 #include "ReverseProxy.h"
 #include "HttpSessionManager.h"
+#include "remap/RemapHitCount.h"
 #ifdef USE_HTTP_DEBUG_LISTS
 #include "Http1ClientSession.h"
 #endif
@@ -374,6 +375,7 @@ start_HttpProxyServer()
 
   // Set up stat page for http connection count
   statPagesManager.register_http("connection_count", register_ShowConnectionCount);
+  statPagesManager.register_http("remap_hits", register_ShowRemapHitCount);
 
   // Alert plugins that connections will be accepted.
   APIHook *hook = lifecycle_hooks->get(TS_LIFECYCLE_PORTS_READY_HOOK);

proxy/http/remap/Makefile.am

@@ -48,6 +48,8 @@ libhttp_remap_a_SOURCES = \
 	NextHopStrategyFactory.cc \
 	RemapConfig.cc \
 	RemapConfig.h \
+        RemapHitCount.cc \
+        RemapHitCount.h \
 	RemapPluginInfo.cc \
 	RemapPluginInfo.h \
 	PluginDso.cc \

proxy/http/remap/RemapHitCount.cc

@@ -0,0 +1,47 @@
+/** @file
+
+  Stats to track remap rule matches
+
+  @section license License
+
+  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.
+ */
+
+#include "RemapHitCount.h"
+#include "UrlRewrite.h"
+
+extern UrlRewrite *rewrite_table;
+
+struct ShowRemapCount : public ShowCont {
+  ShowRemapCount(Continuation *c, HTTPHdr *h) : ShowCont(c, h) { SET_HANDLER(&ShowRemapCount::showHandler); }
+  int
+  showHandler(int event, Event *e)
+  {
+    auto table = rewrite_table->acquire();
+    CHECK_SHOW(show(rewrite_table->PrintRemapHits().c_str()));
+    table->release();
+    return completeJson(event, e);
+  }
+};
+
+Action *
+register_ShowRemapHitCount(Continuation *c, HTTPHdr *h)
+{
+  ShowRemapCount *s = new ShowRemapCount(c, h);
+  this_ethread()->schedule_imm(s);
+  return &s->action;
+}

proxy/http/remap/RemapHitCount.h

@@ -0,0 +1,30 @@
+/** @file
+
+  Show endpoint for remap rule hits
+
+  @section license License
+
+  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.
+ */
+
+#pragma once
+
+#include "HTTP.h"
+#include "I_EventSystem.h"
+#include "Show.h"
+
+Action *register_ShowRemapHitCount(Continuation *, HTTPHdr *);

proxy/http/remap/UrlMapping.cc

@@ -95,6 +95,13 @@ url_mapping::Print() const
          _plugin_inst_list.size());
 }
 
+std::string
+url_mapping::PrintRemapHitCount() const
+{
+  std::string result = "{\"fromURL\": \"" + remapKey + "\", \"hit_count\": " + std::to_string(_hitCount) + "}";
+  return result;
+}
+
 /**
  *
  **/

proxy/http/remap/UrlMapping.h

@@ -29,6 +29,7 @@
 #include "tscore/ink_config.h"
 #include "AclFiltering.h"
 #include "URL.h"
+#include "RemapHitCount.h"
 #include "RemapPluginInfo.h"
 #include "PluginFactory.h"
 #include "tscore/Regex.h"
@@ -93,6 +94,7 @@ class url_mapping
   }
 
   void Print() const;
+  std::string PrintRemapHitCount() const;
 
   int from_path_len = 0;
   URL fromURL;
@@ -112,6 +114,8 @@ class url_mapping
   acl_filter_rule *filter            = nullptr; // acl filtering (list of rules)
   LINK(url_mapping, link);                      // For use with the main Queue linked list holding all the mapping
   std::shared_ptr<NextHopSelectionStrategy> strategy = nullptr;
+  std::string remapKey;
+  std::atomic<uint64_t> _hitCount = 0; // counter can overflow
 
   int
   getRank() const
@@ -124,6 +128,24 @@ class url_mapping
     _rank = rank;
   };
 
+  void
+  setRemapKey()
+  {
+    remapKey = fromURL.string_get_ref();
+  }
+
+  const std::string &
+  getRemapKey()
+  {
+    return remapKey;
+  }
+
+  void
+  incrementCount()
+  {
+    _hitCount++;
+  }
+
 private:
   std::vector<RemapPluginInst *> _plugin_inst_list;
   int _rank = 0;

proxy/http/remap/UrlMappingPathIndex.cc

@@ -91,3 +91,16 @@ UrlMappingPathIndex::Print() const
     m_trie.second->Print();
   }
 }
+
+std::string
+UrlMappingPathIndex::PrintUrlMappingPathIndex() const
+{
+  std::string result;
+  for (auto &m_trie : m_tries) {
+    for (auto const &node : *m_trie.second) {
+      result += node.PrintRemapHitCount();
+      result += ",\n";
+    }
+  }
+  return result;
+}

proxy/http/remap/UrlMappingPathIndex.h

@@ -38,6 +38,7 @@ class UrlMappingPathIndex
   bool Insert(url_mapping *mapping);
   url_mapping *Search(URL *request_url, int request_port, bool normal_search = true) const;
   void Print() const;
+  std::string PrintUrlMappingPathIndex() const;
 
 private:
   typedef Trie<url_mapping> UrlMappingTrie;

proxy/http/remap/UrlRewrite.cc

@@ -182,6 +182,47 @@ UrlRewrite::PrintStore(const MappingsStore &store) const
   }
 }
 
+std::string
+UrlRewrite::PrintRemapHits()
+{
+  std::string result;
+  result += PrintRemapHitsStore(forward_mappings);
+  result += PrintRemapHitsStore(reverse_mappings);
+  result += PrintRemapHitsStore(permanent_redirects);
+  result += PrintRemapHitsStore(temporary_redirects);
+  result += PrintRemapHitsStore(forward_mappings_with_recv_port);
+
+  if (result.size() > 2) {
+    result.pop_back(); // remove the trailing \n
+    result.pop_back(); // remove the trailing ,
+    result = "{\"list\": [\n" + result + " \n]}";
+  }
+
+  return result;
+}
+
+/** Debugging method. */
+std::string
+UrlRewrite::PrintRemapHitsStore(MappingsStore &store)
+{
+  std::string result;
+  if (store.hash_lookup) {
+    for (auto &it : *store.hash_lookup) {
+      result += it.second->PrintUrlMappingPathIndex();
+    }
+  }
+
+  if (!store.regex_list.empty()) {
+    forl_LL(RegexMapping, list_iter, store.regex_list)
+    {
+      result += list_iter->url_map->PrintRemapHitCount();
+      result += ",\n";
+    }
+  }
+
+  return result;
+}
+
 /**
   If a remapping is found, returns a pointer to it otherwise NULL is
   returned.
@@ -551,6 +592,7 @@ UrlRewrite::_addToStore(MappingsStore &store, url_mapping *new_mapping, RegexMap
   bool retval;
 
   new_mapping->setRank(count); // Use the mapping rules number count for rank
+  new_mapping->setRemapKey();  // Used for remap hit stats
   if (is_cur_mapping_regex) {
     store.regex_list.enqueue(reg_map);
     retval = true;
@@ -766,6 +808,9 @@ UrlRewrite::_mappingLookup(MappingsStore &mappings, URL *request_url, int reques
     Debug("url_rewrite", "Using regex mapping with rank %d", (mapping_container.getMapping())->getRank());
     retval = true;
   }
+  if (retval) {
+    (mapping_container.getMapping())->incrementCount();
+  }
   return retval;
 }
 

proxy/http/remap/UrlRewrite.h

@@ -146,6 +146,8 @@ class UrlRewrite : public RefCountObj
 
   void PerformACLFiltering(HttpTransact::State *s, url_mapping *mapping);
   void PrintStore(const MappingsStore &store) const;
+  std::string PrintRemapHits();
+  std::string PrintRemapHitsStore(MappingsStore &store);
 
   void
   DestroyStore(MappingsStore &store)