Cache: Move key generation to module level

The key generation is dependent upon the storage implemenation,
but not on a particular storage instance.

server/modules/filter/cache/cache_storage_api.h

@@ -143,6 +143,18 @@ typedef struct cache_storage_api
                                      uint64_t max_size,
                                      int argc, char* argv[]);
 
+    /**
+     * Create a key for a GWBUF.
+     *
+     * @param query      An SQL query. Must be one contiguous buffer.
+     * @param key        Pointer to key.
+     *
+     * @return CACHE_RESULT_OK if a key was created, otherwise some error code.
+     */
+    cache_result_t (*getKey)(const char* default_db,
+                             const GWBUF* query,
+                             CACHE_KEY* key);
+
     /**
      * Frees an CACHE_STORAGE instance earlier created with createInstance.
      *
@@ -164,20 +176,6 @@ typedef struct cache_storage_api
     cache_result_t (*getInfo)(CACHE_STORAGE* storage,
                               uint32_t what,
                               json_t** info);
-    /**
-     * Create a key for a GWBUF.
-     *
-     * @param storage    Pointer to a CACHE_STORAGE.
-     * @param query      An SQL query. Must be one contiguous buffer.
-     * @param key        Pointer to key.
-     *
-     * @return CACHE_RESULT_OK if a key was created, otherwise some error code.
-     */
-    cache_result_t (*getKey)(CACHE_STORAGE* storage,
-                             const char* default_db,
-                             const GWBUF* query,
-                             CACHE_KEY* key);
-
     /**
      * Get a value from the cache.
      *

server/modules/filter/cache/storage/storage_inmemory/inmemorystorage.cc

@@ -46,6 +46,7 @@ InMemoryStorage::~InMemoryStorage()
 {
 }
 
+// static
 cache_result_t InMemoryStorage::get_key(const char* zdefault_db, const GWBUF* pquery, CACHE_KEY* pkey)
 {
     ss_dassert(GWBUF_IS_CONTIGUOUS(pquery));

server/modules/filter/cache/storage/storage_inmemory/inmemorystorage.hh

@@ -24,7 +24,7 @@ class InMemoryStorage
 public:
     virtual ~InMemoryStorage();
 
-    cache_result_t get_key(const char* zdefault_db, const GWBUF* pquery, CACHE_KEY* pkey);
+    static cache_result_t get_key(const char* zdefault_db, const GWBUF* pquery, CACHE_KEY* pkey);
 
     virtual cache_result_t get_info(uint32_t what, json_t** ppInfo) const = 0;
     virtual cache_result_t get_value(const CACHE_KEY& key, uint32_t flags, GWBUF** ppresult) = 0;

server/modules/filter/cache/storage/storage_inmemory/storage_inmemory.cc

@@ -76,6 +76,21 @@ CACHE_STORAGE* createInstance(cache_thread_model_t model,
     return reinterpret_cast<CACHE_STORAGE*>(sStorage.release());
 }
 
+cache_result_t getKey(const char* zdefault_db,
+                      const GWBUF* pquery,
+                      CACHE_KEY* pkey)
+{
+    // zdefault_db may be NULL.
+    ss_dassert(pquery);
+    ss_dassert(pkey);
+
+    cache_result_t result = CACHE_RESULT_ERROR;
+
+    MXS_EXCEPTION_GUARD(result = InMemoryStorage::get_key(zdefault_db, pquery, pkey));
+
+    return result;
+}
+
 void freeInstance(CACHE_STORAGE* pinstance)
 {
     MXS_EXCEPTION_GUARD(delete reinterpret_cast<InMemoryStorage*>(pinstance));
@@ -94,25 +109,6 @@ cache_result_t getInfo(CACHE_STORAGE* pStorage,
     return result;
 }
 
-cache_result_t getKey(CACHE_STORAGE* pstorage,
-                      const char* zdefault_db,
-                      const GWBUF* pquery,
-                      CACHE_KEY* pkey)
-{
-    ss_dassert(pstorage);
-    // zdefault_db may be NULL.
-    ss_dassert(pquery);
-    ss_dassert(pkey);
-
-    cache_result_t result = CACHE_RESULT_ERROR;
-
-    MXS_EXCEPTION_GUARD(result = reinterpret_cast<InMemoryStorage*>(pstorage)->get_key(zdefault_db,
-                                                                                       pquery,
-                                                                                       pkey));
-
-    return result;
-}
-
 cache_result_t getValue(CACHE_STORAGE* pstorage,
                         const CACHE_KEY* pkey,
                         uint32_t flags,
@@ -221,9 +217,9 @@ CACHE_STORAGE_API* CacheGetStorageAPI()
         {
             initialize,
             createInstance,
+            getKey,
             freeInstance,
             getInfo,
-            getKey,
             getValue,
             putValue,
             delValue,

server/modules/filter/cache/storage/storage_rocksdb/rocksdbstorage.cc

@@ -361,32 +361,8 @@ unique_ptr<RocksDBStorage> RocksDBStorage::Create(const string& storageDirectory
     return sStorage;
 }
 
-cache_result_t RocksDBStorage::getInfo(uint32_t what, json_t** ppInfo) const
+// static
-{
+cache_result_t RocksDBStorage::GetKey(const char* zDefaultDB, const GWBUF* pQuery, CACHE_KEY* pKey)
-    json_t* pInfo = json_object();
-
-    if (pInfo)
-    {
-        auto sStatistics = m_sDb->GetOptions().statistics;
-
-        for_each(rocksdb::TickersNameMap.begin(), rocksdb::TickersNameMap.end(),
-                 [pInfo, sStatistics](const std::pair<rocksdb::Tickers, string>& tickerName) {
-                     json_t* pValue = json_integer(sStatistics->getTickerCount(tickerName.first));
-
-                     if (pValue)
-                     {
-                         json_object_set(pInfo, tickerName.second.c_str(), pValue);
-                         json_decref(pValue);
-                     }
-                 });
-
-        *ppInfo = pInfo;
-    }
-
-    return pInfo ? CACHE_RESULT_OK : CACHE_RESULT_OUT_OF_RESOURCES;
-}
-
-cache_result_t RocksDBStorage::getKey(const char* zDefaultDB, const GWBUF* pQuery, CACHE_KEY* pKey)
 {
     ss_dassert(GWBUF_IS_CONTIGUOUS(pQuery));
 
@@ -444,6 +420,31 @@ cache_result_t RocksDBStorage::getKey(const char* zDefaultDB, const GWBUF* pQuer
     return CACHE_RESULT_OK;
 }
 
+cache_result_t RocksDBStorage::getInfo(uint32_t what, json_t** ppInfo) const
+{
+    json_t* pInfo = json_object();
+
+    if (pInfo)
+    {
+        auto sStatistics = m_sDb->GetOptions().statistics;
+
+        for_each(rocksdb::TickersNameMap.begin(), rocksdb::TickersNameMap.end(),
+                 [pInfo, sStatistics](const std::pair<rocksdb::Tickers, string>& tickerName) {
+                     json_t* pValue = json_integer(sStatistics->getTickerCount(tickerName.first));
+
+                     if (pValue)
+                     {
+                         json_object_set(pInfo, tickerName.second.c_str(), pValue);
+                         json_decref(pValue);
+                     }
+                 });
+
+        *ppInfo = pInfo;
+    }
+
+    return pInfo ? CACHE_RESULT_OK : CACHE_RESULT_OUT_OF_RESOURCES;
+}
+
 cache_result_t RocksDBStorage::getValue(const CACHE_KEY* pKey, uint32_t flags, GWBUF** ppResult)
 {
     // Use the root DB so that we get the value *with* the timestamp at the end.

server/modules/filter/cache/storage/storage_rocksdb/rocksdbstorage.hh

@@ -28,8 +28,9 @@ public:
     static SRocksDBStorage Create(const char* zName, uint32_t ttl, int argc, char* argv[]);
     ~RocksDBStorage();
 
+    static cache_result_t GetKey(const char* zDefaultDB, const GWBUF* pQuery, CACHE_KEY* pKey);
+
     cache_result_t getInfo(uint32_t flags, json_t** ppInfo) const;
-    cache_result_t getKey(const char* zDefaultDB, const GWBUF* pQuery, CACHE_KEY* pKey);
     cache_result_t getValue(const CACHE_KEY* pKey, uint32_t flags, GWBUF** ppResult);
     cache_result_t putValue(const CACHE_KEY* pKey, const GWBUF* pValue);
     cache_result_t delValue(const CACHE_KEY* pKey);

server/modules/filter/cache/storage/storage_rocksdb/storage_rocksdb.cc

@@ -80,21 +80,17 @@ cache_result_t getInfo(CACHE_STORAGE* pStorage,
     return result;
 }
 
-cache_result_t getKey(CACHE_STORAGE* pStorage,
+cache_result_t getKey(const char* zDefaultDB,
-                      const char* zDefaultDB,
                       const GWBUF* pQuery,
                       CACHE_KEY* pKey)
 {
-    ss_dassert(pStorage);
     // zDefaultDB may be NULL.
     ss_dassert(pQuery);
     ss_dassert(pKey);
 
     cache_result_t result = CACHE_RESULT_ERROR;
 
-    MXS_EXCEPTION_GUARD(result = reinterpret_cast<RocksDBStorage*>(pStorage)->getKey(zDefaultDB,
+    MXS_EXCEPTION_GUARD(result = RocksDBStorage::GetKey(zDefaultDB, pQuery, pKey));
-                                                                                     pQuery,
-                                                                                     pKey));
 
     return result;
 }
@@ -206,9 +202,9 @@ CACHE_STORAGE_API* CacheGetStorageAPI()
         {
             initialize,
             createInstance,
+            getKey,
             freeInstance,
             getInfo,
-            getKey,
             getValue,
             putValue,
             delValue,

server/modules/filter/cache/storagefactory.cc

@@ -238,3 +238,11 @@ Storage* StorageFactory::createRawStorage(cache_thread_model_t model,
 
     return pStorage;
 }
+
+cache_result_t StorageFactory::get_key(const char* zDefaultDb,
+                                       const GWBUF* pQuery,
+                                       CACHE_KEY* pKey) const
+{
+    return m_pApi->getKey(zDefaultDb, pQuery, pKey);
+}
+

server/modules/filter/cache/storagefactory.hh

@@ -95,6 +95,19 @@ public:
                               uint64_t max_size,
                               int argc, char* argv[]);
 
+    /**
+     * Create a key for a GWBUF.
+     *
+     * @param zDefaultDb  The default DB or NULL.
+     * @param query       An SQL query. Must be one contiguous buffer.
+     * @param pKey        Pointer to object where key will be stored.
+     *
+     * @return CACHE_RESULT_OK if a key was created, otherwise some error code.
+     */
+    cache_result_t get_key(const char* zDefaultDb,
+                           const GWBUF* pQuery,
+                           CACHE_KEY* pKey) const;
+
 private:
     StorageFactory(void* handle, CACHE_STORAGE_API* pApi, uint32_t capabilities);
 

server/modules/filter/cache/storagereal.cc

@@ -37,7 +37,7 @@ cache_result_t StorageReal::get_key(const char* zDefaultDb,
                                     const GWBUF* pQuery,
                                     CACHE_KEY* pKey) const
 {
-    return m_pApi->getKey(m_pStorage, zDefaultDb, pQuery, pKey);
+    return m_pApi->getKey(zDefaultDb, pQuery, pKey);
 }
 
 cache_result_t StorageReal::get_value(const CACHE_KEY& key,