feat(cache): Check cache database capacity

`cache_occupied_space()` would return the used size in caching database.

close #488

accelerator/cli_info.h

@@ -54,6 +54,7 @@ typedef enum ta_cli_arg_value_e {
   NO_GTTA,
   BUFFER_LIST,
   DONE_LIST,
+  REDIS_CAPACITY,
 
   /** LOGGER */
   QUIET,
@@ -90,6 +91,7 @@ static struct ta_cli_argument_s {
     {"no-gtta", no_argument, NULL, NO_GTTA, "Disable getTransactionToConfirm (gTTA) when sending transacation"},
     {"buffer_list", required_argument, NULL, BUFFER_LIST, "Set the value of `buffer_list_name`"},
     {"done_list", required_argument, NULL, DONE_LIST, "Set the value of `done_list_name`"},
+    {"redis_capacity", required_argument, NULL, REDIS_CAPACITY, "Set the maximum redis capacity`"},
     {"quiet", no_argument, NULL, QUIET, "Disable logger"},
     {NULL, 0, NULL, 0, NULL}};
 

accelerator/config.c

@@ -175,6 +175,9 @@ status_t cli_core_set(ta_core_t* const core, int key, char* const value) {
     case DONE_LIST:
       cache->done_list_name = value;
       break;
+    case REDIS_MAX_CAPACITY:
+      cache->redis_capacity = value;
+      break;
 
     // File configuration
     case CONF_CLI: {
@@ -224,6 +227,7 @@ status_t ta_core_default_init(ta_core_t* const core) {
   cache->cache_state = false;
   cache->buffer_list_name = BUFFER_LIST_NAME;
   cache->done_list_name = DONE_LIST_NAME;
+  cache->redis_capacity = REDIS_MAX_CAPACITY;
 
   ta_log_info("Initializing IRI configuration\n");
   iota_conf->milestone_depth = MILESTONE_DEPTH;

accelerator/config.h

@@ -55,7 +55,8 @@ extern "C" {
 #define MAM_FILE_PREFIX "/tmp/mam_bin_XXXXXX"
 #define BUFFER_LIST_NAME "txn_buff_list"
 #define DONE_LIST_NAME "done_txn_buff_list"
-#define IRI_HEALTH_TRACK_PERIOD 1800  // Check every half hour in default
+#define REDIS_MAX_CAPACITY 170 * 1024 * 1024  // default in 170MB
+#define IRI_HEALTH_TRACK_PERIOD 1800          // Check every half hour in default
 
 /** @name Redis connection config */
 /** @{ */
@@ -96,6 +97,7 @@ typedef struct ta_cache_s {
   char* done_list_name;   /**< Name of the list to store successfully broadcast transactions from buffer */
   uint16_t port;          /**< Binding port of redis server */
   bool cache_state;       /**< Set it true to turn on cache server */
+  long int redis_capacity /**< The maximum capacity of redis cache server */
 } ta_cache_t;
 
 /** struct type of accelerator core */

accelerator/main.c

@@ -40,6 +40,11 @@ void health_track(void* arg) {
       }
     }
 
+    // The usage exceeds the maximum redis capacity
+    if (core->cache.redis_capacity < cache_occupied_space()) {
+      // TODO clean redis
+    }
+
     sleep(core->ta_conf.health_track_period);
   }
 }

tests/unit-test/test_cache.c

@@ -75,6 +75,8 @@ void test_cache_list_pop(void) {
   TEST_ASSERT_EQUAL_STRING(TEST_UUID, res);
 }
 
+void test_cache_occupied_space() { TEST_ASSERT_GREATER_THAN(-1, cache_occupied_space()); }
+
 int main(void) {
   UNITY_BEGIN();
   cache_init(true, REDIS_HOST, REDIS_PORT);
@@ -87,6 +89,7 @@ int main(void) {
   RUN_TEST(test_cache_list_at);
   RUN_TEST(test_cache_list_size);
   RUN_TEST(test_cache_list_pop);
+  RUN_TEST(test_cache_occupied_space);
   cache_stop();
   return UNITY_END();
 }

utils/cache/backend_redis.c

@@ -6,7 +6,9 @@
  * "LICENSE" at the root of this distribution.
  */
 
+#include <errno.h>
 #include <hiredis/hiredis.h>
+#include <limits.h>
 #include "cache.h"
 #include "common/logger.h"
 
@@ -227,6 +229,32 @@ static status_t redis_list_pop(redisContext* c, const char* const key, char* res
   return ret;
 }
 
+long int redis_occupied_space(redisContext* c) {
+  const char size_field[] = "used_memory:";
+  redisReply* reply = redisCommand(c, "INFO");
+  if (reply->type == REDIS_REPLY_STRING) {
+    // Parsing the result returned by redis. Get informationa from field `used_memory`
+    char* str = strstr(reply->str, size_field);
+    char* size_str = strtok(str, "\n");
+    char* ptr = size_str + strlen(size_field);
+
+    char* strtol_p = NULL;
+    long int strtol_temp;
+    strtol_temp = strtol(ptr, &strtol_p, 10);
+    if (strtol_p != ptr && errno != ERANGE && strtol_temp >= INT_MIN && strtol_temp <= INT_MAX) {
+      freeReplyObject(reply);
+      return strtol_temp;
+    } else {
+      ta_log_error("Malformed input or illegal input character\n");
+    }
+  } else {
+    ta_log_error("%s\n", "Failed to operate redis command.");
+  }
+
+  freeReplyObject(reply);
+  return -1;
+}
+
 /*
  * Public functions
  */
@@ -328,3 +356,12 @@ status_t cache_list_pop(const char* const key, char* res) {
   }
   return redis_list_pop(CONN(cache)->rc, key, res);
 }
+
+long int cache_occupied_space() {
+  if (!cache_state) {
+    ta_log_info("%s\n", "SC_CACHE_OFF");
+    return SC_CACHE_OFF;
+  }
+
+  return redis_occupied_space(CONN(cache)->rc);
+}

utils/cache/cache.h

@@ -187,6 +187,15 @@ status_t cache_list_exist(const char* const key, const char* const value, const
  */
 status_t cache_list_pop(const char* const key, char* res);
 
+/**
+ * Get the size of redis occupied space.
+ *
+ * @return
+ * - Used size of the cache database on success
+ * - `-1` on error
+ */
+long int cache_occupied_space();
+
 #ifdef __cplusplus
 }
 #endif