Order output of commands returning random arrays using table.sort when called from Lua, partially fixing issue #165. The issue is yet not completely fixed since we can't add the REDIS_CMD_SORT_FOR_SCRIPT flag in SORT currently, both because it may contain NULLs and because it is not cool to re-sort everything at every call when instead this should be sorted only if BY <constant> is used.

This commit is contained in:
antirez 2012-01-31 16:09:21 +01:00
parent 8dd19d818f
commit 548efd91e5
3 changed files with 36 additions and 9 deletions

View File

@ -102,7 +102,10 @@ struct redisCommand *commandTable;
* s: command not allowed in scripts.
* R: random command. Command is not deterministic, that is, the same command
* with the same arguments, with the same key space, may have different
* results. For instance SPOP and RANDOMKEY are two random commands. */
* results. For instance SPOP and RANDOMKEY are two random commands.
* S: Sort command output array if called from script, so that the output
* is deterministic.
*/
struct redisCommand redisCommandTable[] = {
{"get",getCommand,2,"r",0,NULL,1,1,1,0,0},
{"set",setCommand,3,"wm",0,noPreloadGetKeys,1,1,1,0,0},
@ -145,13 +148,13 @@ struct redisCommand redisCommandTable[] = {
{"scard",scardCommand,2,"r",0,NULL,1,1,1,0,0},
{"spop",spopCommand,2,"wRs",0,NULL,1,1,1,0,0},
{"srandmember",srandmemberCommand,2,"rR",0,NULL,1,1,1,0,0},
{"sinter",sinterCommand,-2,"r",0,NULL,1,-1,1,0,0},
{"sinter",sinterCommand,-2,"rS",0,NULL,1,-1,1,0,0},
{"sinterstore",sinterstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0},
{"sunion",sunionCommand,-2,"r",0,NULL,1,-1,1,0,0},
{"sunion",sunionCommand,-2,"rS",0,NULL,1,-1,1,0,0},
{"sunionstore",sunionstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0},
{"sdiff",sdiffCommand,-2,"r",0,NULL,1,-1,1,0,0},
{"sdiff",sdiffCommand,-2,"rS",0,NULL,1,-1,1,0,0},
{"sdiffstore",sdiffstoreCommand,-3,"wm",0,NULL,1,-1,1,0,0},
{"smembers",sinterCommand,2,"r",0,NULL,1,1,1,0,0},
{"smembers",sinterCommand,2,"rS",0,NULL,1,1,1,0,0},
{"zadd",zaddCommand,-4,"wm",0,NULL,1,1,1,0,0},
{"zincrby",zincrbyCommand,4,"wm",0,NULL,1,1,1,0,0},
{"zrem",zremCommand,-3,"w",0,NULL,1,1,1,0,0},
@ -177,8 +180,8 @@ struct redisCommand redisCommandTable[] = {
{"hincrbyfloat",hincrbyfloatCommand,4,"wm",0,NULL,1,1,1,0,0},
{"hdel",hdelCommand,-3,"w",0,NULL,1,1,1,0,0},
{"hlen",hlenCommand,2,"r",0,NULL,1,1,1,0,0},
{"hkeys",hkeysCommand,2,"r",0,NULL,1,1,1,0,0},
{"hvals",hvalsCommand,2,"r",0,NULL,1,1,1,0,0},
{"hkeys",hkeysCommand,2,"rS",0,NULL,1,1,1,0,0},
{"hvals",hvalsCommand,2,"rS",0,NULL,1,1,1,0,0},
{"hgetall",hgetallCommand,2,"r",0,NULL,1,1,1,0,0},
{"hexists",hexistsCommand,3,"r",0,NULL,1,1,1,0,0},
{"incrby",incrbyCommand,3,"wm",0,NULL,1,1,1,0,0},
@ -196,7 +199,7 @@ struct redisCommand redisCommandTable[] = {
{"expireat",expireatCommand,3,"w",0,NULL,1,1,1,0,0},
{"pexpire",pexpireCommand,3,"w",0,NULL,1,1,1,0,0},
{"pexpireat",pexpireatCommand,3,"w",0,NULL,1,1,1,0,0},
{"keys",keysCommand,2,"r",0,NULL,0,0,0,0,0},
{"keys",keysCommand,2,"rS",0,NULL,0,0,0,0,0},
{"dbsize",dbsizeCommand,1,"r",0,NULL,0,0,0,0,0},
{"auth",authCommand,2,"rs",0,NULL,0,0,0,0,0},
{"ping",pingCommand,1,"r",0,NULL,0,0,0,0,0},
@ -1118,6 +1121,7 @@ void populateCommandTable(void) {
case 'f': c->flags |= REDIS_CMD_FORCE_REPLICATION; break;
case 's': c->flags |= REDIS_CMD_NOSCRIPT; break;
case 'R': c->flags |= REDIS_CMD_RANDOM; break;
case 'S': c->flags |= REDIS_CMD_SORT_FOR_SCRIPT; break;
default: redisPanic("Unsupported command flag"); break;
}
f++;

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@ -77,6 +77,7 @@
#define REDIS_CMD_PUBSUB 32 /* "p" flag */
#define REDIS_CMD_NOSCRIPT 64 /* "s" flag */
#define REDIS_CMD_RANDOM 128 /* "R" flag */
#define REDIS_CMD_SORT_FOR_SCRIPT 256 /* "S" flag */
/* Object types */
#define REDIS_STRING 0

View File

@ -27,7 +27,7 @@ int redis_math_randomseed (lua_State *L);
* is like a normal client that bypasses all the slow I/O paths.
*
* Note: in this function we do not do any sanity check as the reply is
* generated by Redis directly. This allows use to go faster.
* generated by Redis directly. This allows us to go faster.
* The reply string can be altered during the parsing as it is discared
* after the conversion is completed.
*
@ -128,6 +128,22 @@ void luaPushError(lua_State *lua, char *error) {
lua_settable(lua,-3);
}
/* Sort the array currently in the stack. We do this to make the output
* of commands like KEYS or SMEMBERS something deterministic when called
* from Lua (to play well with AOf/replication).
*
* The array is sorted using table.sort itself, and assuming all the
* list elements are strings. */
void luaSortArray(lua_State *lua) {
/* Initial Stack: array */
lua_getglobal(lua,"table");
lua_pushstring(lua,"sort");
lua_gettable(lua,-2); /* Stack: array, table, table.sort */
lua_pushvalue(lua,-3); /* Stack: array, table, table.sort, array */
lua_call(lua,1,0); /* Stack: array (sorted), table */
lua_pop(lua,1); /* Stack: array (sorted) */
}
int luaRedisGenericCommand(lua_State *lua, int raise_error) {
int j, argc = lua_gettop(lua);
struct redisCommand *cmd;
@ -208,6 +224,12 @@ int luaRedisGenericCommand(lua_State *lua, int raise_error) {
}
if (raise_error && reply[0] != '-') raise_error = 0;
redisProtocolToLuaType(lua,reply);
/* Sort the output array if needed, assuming it is a non-null multi bulk
* reply as expected. */
if ((cmd->flags & REDIS_CMD_SORT_FOR_SCRIPT) &&
(reply[0] == '*' && reply[1] != '-')) {
luaSortArray(lua);
}
sdsfree(reply);
cleanup: