Auto rehash keys on read miss + config.ini

Author: nicolasff

redis.c

@@ -63,6 +63,7 @@ PHP_INI_BEGIN()
 	PHP_INI_ENTRY("redis.arrays.previous", "", PHP_INI_ALL, NULL)
 	PHP_INI_ENTRY("redis.arrays.functions", "", PHP_INI_ALL, NULL)
 	PHP_INI_ENTRY("redis.arrays.index", "", PHP_INI_ALL, NULL)
+	PHP_INI_ENTRY("redis.arrays.autorehash", "", PHP_INI_ALL, NULL)
 PHP_INI_END()
 
 ZEND_DECLARE_MODULE_GLOBALS(redis)

redis_array.c

@@ -229,7 +229,7 @@ PHP_METHOD(RedisArray, __construct)
 }
 
 static void
-ra_forward_call(INTERNAL_FUNCTION_PARAMETERS, RedisArray *ra, const char *cmd, int cmd_len, zval *z_args) {
+ra_forward_call(INTERNAL_FUNCTION_PARAMETERS, RedisArray *ra, const char *cmd, int cmd_len, zval *z_args, zval *z_new_target) {
 
 	zval **zp_tmp, z_tmp;
 	char *key;
@@ -301,8 +301,12 @@ ra_forward_call(INTERNAL_FUNCTION_PARAMETERS, RedisArray *ra, const char *cmd, i
 
 		// check if we have an error.
 		if(failed && ra->prev && !b_write_cmd) { // there was an error reading, try with prev ring.
-			/* php_printf("ERROR, FALLBACK TO PREVIOUS RING.\n"); */
-			ra_forward_call(INTERNAL_FUNCTION_PARAM_PASSTHRU, ra->prev, cmd, cmd_len, z_args);
+			/* ERROR, FALLBACK TO PREVIOUS RING and forward a reference to the first redis instance we were looking at. */
+			ra_forward_call(INTERNAL_FUNCTION_PARAM_PASSTHRU, ra->prev, cmd, cmd_len, z_args, z_new_target?z_new_target:redis_inst);
+		}
+
+		if(!failed && !b_write_cmd && z_new_target && ra->auto_rehash) { /* move key from old ring to new ring */
+				ra_move_key(key, key_len, redis_inst, z_new_target TSRMLS_CC);
 		}
 	}
 
@@ -328,7 +332,7 @@ PHP_METHOD(RedisArray, __call)
 		RETURN_FALSE;
 	}
 
-	ra_forward_call(INTERNAL_FUNCTION_PARAM_PASSTHRU, ra, cmd, cmd_len, z_args);
+	ra_forward_call(INTERNAL_FUNCTION_PARAM_PASSTHRU, ra, cmd, cmd_len, z_args, NULL);
 }
 
 PHP_METHOD(RedisArray, _hosts)

redis_array.h

@@ -32,6 +32,7 @@ typedef struct RedisArray_ {
 	zval *z_fun;	/* key extractor */
 	zval *z_pure_cmds;	/* hash table */
 
+	int auto_rehash; /* migrate keys on read operations */
 	struct RedisArray_ *prev;
 } RedisArray;
 

redis_array_impl.c

@@ -152,9 +152,10 @@ RedisArray *ra_load_array(const char *name TSRMLS_DC) {
 	zval *z_params_prev, **z_prev;
 	zval *z_params_funs, **z_data_pp, *z_fun = NULL;
 	zval *z_params_index;
+	zval *z_params_autorehash;
 	RedisArray *ra = NULL;
 
-	zend_bool b_index = 0;
+	zend_bool b_index = 0, b_autorehash = 0;
 	HashTable *hHosts = NULL, *hPrev = NULL;
 
 	/* find entry */
@@ -197,8 +198,19 @@ RedisArray *ra_load_array(const char *name TSRMLS_DC) {
 		}
 	}
 
+	/* find autorehash option */
+	MAKE_STD_ZVAL(z_params_autorehash);
+	array_init(z_params_autorehash);
+	sapi_module.treat_data(PARSE_STRING, estrdup(INI_STR("redis.arrays.autorehash")), z_params_autorehash TSRMLS_CC);
+	if (zend_hash_find(Z_ARRVAL_P(z_params_autorehash), name, strlen(name) + 1, (void **) &z_data_pp) != FAILURE) {
+		if(Z_TYPE_PP(z_data_pp) == IS_STRING && strncmp(Z_STRVAL_PP(z_data_pp), "1", 1) == 0) {
+			b_autorehash = 1;
+		}
+	}
+
 	/* create RedisArray object */
 	ra = ra_make_array(hHosts, z_fun, hPrev, b_index TSRMLS_CC);
+	ra->auto_rehash = b_autorehash;
 
 	/* cleanup */
 	zval_dtor(z_params_hosts);
@@ -209,6 +221,8 @@ RedisArray *ra_load_array(const char *name TSRMLS_DC) {
 	efree(z_params_funs);
 	zval_dtor(z_params_index);
 	efree(z_params_index);
+	zval_dtor(z_params_autorehash);
+	efree(z_params_autorehash);
 
 	return ra;
 }
@@ -760,7 +774,7 @@ ra_move_list(const char *key, int key_len, zval *z_from, zval *z_to TSRMLS_DC) {
 	return ra_move_collection(key, key_len, z_from, z_to, 3, cmd_list, 1, cmd_add TSRMLS_CC);
 }
 
-static void
+void
 ra_move_key(const char *key, int key_len, zval *z_from, zval *z_to TSRMLS_DC) {
 
 	long type = ra_get_key_type(z_from, key, key_len TSRMLS_CC);

redis_array_impl.h

@@ -11,6 +11,7 @@ RedisArray *ra_make_array(HashTable *hosts, zval *z_fun, HashTable *hosts_prev,
 zval *ra_find_node(RedisArray *ra, const char *key, int key_len, int *out_pos TSRMLS_DC);
 void ra_init_function_table(RedisArray *ra);
 
+void ra_move_key(const char *key, int key_len, zval *z_from, zval *z_to TSRMLS_DC);
 char * ra_find_key(RedisArray *ra, zval *z_args, const char *cmd, int *key_len);
 void ra_index_multi(zval *z_redis TSRMLS_DC);