FEATURE: Add touch command

docs/ascii-protocol/ch04-command-key-value.md

@@ -110,3 +110,22 @@ decr <key> <delta> [<flags> <exptime> <initial>] [noreply]\r\n
 | "TYPE_MISMATCH"      | 해당 아이템이 key-value 타입이 아님
 | "CLIENT_ERROR"       | 클라이언트에서 잘못된 질의를 했음을 의미. 이어 나오는 문자열을 통해 오류의 원인을 파악 가능. 예) invalid numeric delta argument, cannot increment or decrement non-numeric value
 | "SERVER ERROR"       | 서버 측의 오류로 연산하지 못했음을 의미. 이어 나오는 문자열을 통해 오류의 원인을 파악 가능. 예) out of memory
+
+## touch (Item의 expiretime 변경)
+
+key에 해당하는 item을 fetch 하지 않고 expiretime을 재설정하는 명령은 아래와 같다. 이 명령은 모든 item 타입에 대해 적용이 가능하다.
+
+```
+touch <key> <exptime> [noreply]\r\n
+```
+
+- \<key\> - 대상 item의 key string
+- \<exptime\> - 재설정할 expiretime 값
+
+이 명령의 response string과 그 의미는 아래와 같다.
+
+| Response String          | 설명                            |
+| ------------------------ | ------------------------------- |
+| "TOUCHED"                | 성공                            |
+| "NOT_FOUND"              | key miss                        |
+| "CLIENT_ERROR bad value" | exptime 값이 유효하지 않은 경우 |

memcached.c

@@ -13085,6 +13085,53 @@ static void process_setattr_command(conn *c, token_t *tokens, const size_t ntoke
     }
 }
 
+static void process_touch_command(conn *c, token_t *tokens, const size_t ntokens)
+{
+    assert(c != NULL);
+    assert(c->ewouldblock == false);
+    char *key = tokens[KEY_TOKEN].value;
+    size_t nkey = tokens[KEY_TOKEN].length;
+
+    if (nkey > KEY_MAX_LENGTH) {
+        out_string(c, "CLIENT_ERROR bad command line format");
+        return;
+    }
+
+    ENGINE_ERROR_CODE ret;
+    item_attr attr_data;
+    ENGINE_ITEM_ATTR attr_id = ATTR_EXPIRETIME;
+    int64_t exptime;
+
+    set_noreply_maybe(c, tokens, ntokens);
+
+    if (! safe_strtoll(tokens[KEY_TOKEN+1].value, &exptime)) {
+        ret = ENGINE_EBADVALUE;
+    } else {
+        attr_data.exptime = realtime(exptime);
+        ret = mc_engine.v1->setattr(mc_engine.v0, c, key, nkey,
+                                    &attr_id, 1, &attr_data, 0);
+        CONN_CHECK_AND_SET_EWOULDBLOCK(ret, c);
+        if (settings.detail_enabled) {
+            stats_prefix_record_setattr(key, nkey);
+        }
+    }
+
+    switch (ret) {
+    case ENGINE_SUCCESS:
+        STATS_HITS(c, setattr, key, nkey);
+        out_string(c, "TOUCHED");
+        break;
+    case ENGINE_KEY_ENOENT:
+        STATS_MISSES(c, setattr, key, nkey);
+        out_string(c, "NOT_FOUND");
+        break;
+    default:
+        STATS_CMD_NOKEY(c, setattr);
+        if (ret == ENGINE_EBADVALUE) out_string(c, "CLIENT_ERROR bad value");
+        else handle_unexpected_errorcode_ascii(c, __func__, ret);
+    }
+}
+
 static void process_command_ascii(conn *c, char *command, int cmdlen)
 {
     /* One more token is reserved in tokens strucure
@@ -13206,6 +13253,10 @@ static void process_command_ascii(conn *c, char *command, int cmdlen)
     {
         process_config_command(c, tokens, ntokens);
     }
+    else if ((ntokens >= 4 && ntokens <= 5) && (strcmp(tokens[COMMAND_TOKEN].value, "touch") == 0))
+    {
+        process_touch_command(c, tokens, ntokens);
+    }
 #ifdef ENABLE_ZK_INTEGRATION
     else if ((ntokens >= 3) && (strcmp(tokens[COMMAND_TOKEN].value, "zkensemble") == 0))
     {

t/tlist/engine_default_b.txt

@@ -102,3 +102,4 @@
 ./t/nested_prefix.t
 ./t/keyscan.t
 ./t/prefixscan.t
+./t/touch.t

t/tlist/engine_default_s.txt

@@ -95,3 +95,4 @@
 ./t/nested_prefix.t
 ./t/keyscan.t
 ./t/prefixscan.t
+./t/touch.t

t/touch.t

@@ -0,0 +1,81 @@
+#!/usr/bin/perl
+
+use strict;
+use Test::More tests =>19;
+use FindBin qw($Bin);
+use lib "$Bin/lib";
+use MemcachedTest;
+
+my $engine = shift;
+my $server = get_memcached($engine);
+my $sock = $server->sock;
+
+my $cmd;
+my $val;
+my $rst;
+my $expire;
+
+# Initialize
+$cmd = "set key 0 0 5"; $val = "datum"; $rst = "STORED";
+mem_cmd_is($sock, $cmd, $val, $rst);
+$cmd = "lop create lkey 0 0 1 error"; $rst = "CREATED";
+mem_cmd_is($sock, $cmd, "", $rst);
+$cmd = "sop create skey 0 0 1 error"; $rst = "CREATED";
+mem_cmd_is($sock, $cmd, "", $rst);
+$cmd = "mop create mkey 0 0 1 error"; $rst = "CREATED";
+mem_cmd_is($sock, $cmd, "", $rst);
+$cmd = "bop create bkey 0 0 1 error"; $rst = "CREATED";
+mem_cmd_is($sock, $cmd, "", $rst);
+
+# Success Cases
+# key value
+$cmd = "touch key 1"; $rst = "TOUCHED";
+mem_cmd_is($sock, $cmd, "", $rst);
+$cmd = "getattr key expiretime";
+$rst = "ATTR expiretime=1\n"
+     . "END";
+mem_cmd_is($sock, $cmd, "", $rst);
+# list
+$cmd = "touch lkey 1"; $rst = "TOUCHED";
+mem_cmd_is($sock, $cmd, "", $rst);
+$cmd = "getattr lkey expiretime";
+$rst = "ATTR expiretime=1\n"
+     . "END";
+mem_cmd_is($sock, $cmd, "", $rst);
+# set
+$cmd = "touch skey 1"; $rst = "TOUCHED";
+mem_cmd_is($sock, $cmd, "", $rst);
+$cmd = "getattr skey expiretime";
+$rst = "ATTR expiretime=1\n"
+     . "END";
+mem_cmd_is($sock, $cmd, "", $rst);
+# map
+$cmd = "touch mkey 1"; $rst = "TOUCHED";
+mem_cmd_is($sock, $cmd, "", $rst);
+$cmd = "getattr mkey expiretime";
+$rst = "ATTR expiretime=1\n"
+     . "END";
+mem_cmd_is($sock, $cmd, "", $rst);
+#btree
+$cmd = "touch bkey 1"; $rst = "TOUCHED";
+mem_cmd_is($sock, $cmd, "", $rst);
+$cmd = "getattr bkey expiretime";
+$rst = "ATTR expiretime=1\n"
+     . "END";
+mem_cmd_is($sock, $cmd, "", $rst);
+
+# Fail Cases
+# bad value
+$cmd = "set key 0 0 5"; $val = "datum"; $rst = "STORED";
+mem_cmd_is($sock, $cmd, $val, $rst);
+$cmd = "touch key str"; $rst = "CLIENT_ERROR bad value";
+mem_cmd_is($sock, $cmd, "", $rst);
+# not exist key
+$expire = time() - 1;
+$cmd = "touch key $expire"; $rst = "TOUCHED";
+mem_cmd_is($sock, $cmd, "", $rst);
+$cmd = "touch key 1"; $rst = "NOT_FOUND";
+mem_cmd_is($sock, $cmd, "", $rst);
+
+# after test
+release_memcached($engine, $server);