char *charset = "0123456789abcdef";
int j;
- if (!fp) {
- redisLog(REDIS_WARNING,
- "Unrecovarable error: can't open /dev/urandom:%s" ,strerror(errno));
- exit(1);
+ if (fp == NULL || fread(p,REDIS_CLUSTER_NAMELEN,1,fp) == 0) {
+ for (j = 0; j < REDIS_CLUSTER_NAMELEN; j++)
+ p[j] = rand();
}
- fread(p,REDIS_CLUSTER_NAMELEN,1,fp);
for (j = 0; j < REDIS_CLUSTER_NAMELEN; j++)
p[j] = charset[p[j] & 0x0F];
fclose(fp);
* If the slot is already assigned to another instance this is considered
* an error and REDIS_ERR is returned. */
int clusterAddSlot(clusterNode *n, int slot) {
- redisAssert(clusterNodeSetSlotBit(n,slot) == 0);
+ if (clusterNodeSetSlotBit(n,slot) != 0)
+ return REDIS_ERR;
server.cluster.slots[slot] = n;
return REDIS_OK;
}
+/* Delete the specified slot marking it as unassigned.
+ * Returns REDIS_OK if the slot was assigned, otherwise if the slot was
+ * already unassigned REDIS_ERR is returned. */
+int clusterDelSlot(int slot) {
+ clusterNode *n = server.cluster.slots[slot];
+
+ if (!n) return REDIS_ERR;
+ redisAssert(clusterNodeClearSlotBit(n,slot) == 1);
+ server.cluster.slots[slot] = NULL;
+ return REDIS_OK;
+}
+
/* -----------------------------------------------------------------------------
* Cluster state evaluation function
* -------------------------------------------------------------------------- */
return ci;
}
+int getSlotOrReply(redisClient *c, robj *o) {
+ long long slot;
+
+ if (getLongLongFromObject(o,&slot) != REDIS_OK ||
+ slot < 0 || slot > REDIS_CLUSTER_SLOTS)
+ {
+ addReplyError(c,"Invalid or out of range slot");
+ return -1;
+ }
+ return (int) slot;
+}
+
void clusterCommand(redisClient *c) {
if (server.cluster_enabled == 0) {
addReplyError(c,"This instance has cluster support disabled");
o = createObject(REDIS_STRING,ci);
addReplyBulk(c,o);
decrRefCount(o);
- } else if (!strcasecmp(c->argv[1]->ptr,"addslots") && c->argc >= 3) {
- int j;
- long long slot;
+ } else if ((!strcasecmp(c->argv[1]->ptr,"addslots") ||
+ !strcasecmp(c->argv[1]->ptr,"delslots")) && c->argc >= 3) {
+ int j, slot;
unsigned char *slots = zmalloc(REDIS_CLUSTER_SLOTS);
+ int del = !strcasecmp(c->argv[1]->ptr,"delslots");
memset(slots,0,REDIS_CLUSTER_SLOTS);
/* Check that all the arguments are parsable and that all the
* slots are not already busy. */
for (j = 2; j < c->argc; j++) {
- if (getLongLongFromObject(c->argv[j],&slot) != REDIS_OK ||
- slot < 0 || slot > REDIS_CLUSTER_SLOTS)
- {
- addReplyError(c,"Invalid or out of range slot index");
+ if ((slot = getSlotOrReply(c,c->argv[j])) == -1) {
zfree(slots);
return;
}
- if (server.cluster.slots[slot]) {
- addReplyErrorFormat(c,"Slot %lld is already busy", slot);
+ if (del && server.cluster.slots[slot] == NULL) {
+ addReplyErrorFormat(c,"Slot %d is already unassigned", slot);
+ zfree(slots);
+ return;
+ } else if (!del && server.cluster.slots[slot]) {
+ addReplyErrorFormat(c,"Slot %d is already busy", slot);
zfree(slots);
return;
}
}
for (j = 0; j < REDIS_CLUSTER_SLOTS; j++) {
if (slots[j]) {
- int retval = clusterAddSlot(server.cluster.myself,j);
-
+ int retval;
+
+ /* If this slot was set as importing we can clear this
+ * state as now we are the real owner of the slot. */
+ if (server.cluster.importing_slots_from[j])
+ server.cluster.importing_slots_from[j] = NULL;
+
+ retval = del ? clusterDelSlot(j) :
+ clusterAddSlot(server.cluster.myself,j);
redisAssert(retval == REDIS_OK);
}
}
/* SETSLOT 10 MIGRATING <instance ID> */
/* SETSLOT 10 IMPORTING <instance ID> */
/* SETSLOT 10 STABLE */
- long long aux;
- unsigned int slot;
+ int slot;
clusterNode *n;
- if (getLongLongFromObjectOrReply(c,c->argv[2],&aux,NULL) != REDIS_OK)
- return;
- if (aux < 0 || aux >= REDIS_CLUSTER_SLOTS) {
- addReplyError(c,"Slot out of range");
- return;
- }
- slot = (unsigned int) aux;
- if (server.cluster.slots[slot] != server.cluster.myself) {
- addReplyErrorFormat(c,"I'm not the owner of hash slot %u",slot);
- return;
- }
+ if ((slot = getSlotOrReply(c,c->argv[2])) == -1) return;
+
if (!strcasecmp(c->argv[3]->ptr,"migrating") && c->argc == 5) {
+ if (server.cluster.slots[slot] != server.cluster.myself) {
+ addReplyErrorFormat(c,"I'm not the owner of hash slot %u",slot);
+ return;
+ }
if ((n = clusterLookupNode(c->argv[4]->ptr)) == NULL) {
addReplyErrorFormat(c,"I don't know about node %s",
(char*)c->argv[4]->ptr);
}
server.cluster.migrating_slots_to[slot] = n;
} else if (!strcasecmp(c->argv[3]->ptr,"importing") && c->argc == 5) {
+ if (server.cluster.slots[slot] == server.cluster.myself) {
+ addReplyErrorFormat(c,
+ "I'm already the owner of hash slot %u",slot);
+ return;
+ }
if ((n = clusterLookupNode(c->argv[4]->ptr)) == NULL) {
addReplyErrorFormat(c,"I don't know about node %s",
(char*)c->argv[3]->ptr);
}
server.cluster.importing_slots_from[slot] = n;
} else if (!strcasecmp(c->argv[3]->ptr,"stable") && c->argc == 4) {
+ /* CLUSTER SETSLOT <SLOT> STABLE */
server.cluster.importing_slots_from[slot] = NULL;
+ server.cluster.migrating_slots_to[slot] = NULL;
+ } else if (!strcasecmp(c->argv[3]->ptr,"node") && c->argc == 4) {
+ /* CLUSTER SETSLOT <SLOT> NODE <NODE ID> */
+ clusterNode *n = clusterLookupNode(c->argv[4]->ptr);
+
+ if (!n) addReplyErrorFormat(c,"Unknown node %s",
+ (char*)c->argv[4]->ptr);
+ /* If this hash slot was served by 'myself' before to switch
+ * make sure there are no longer local keys for this hash slot. */
+ if (server.cluster.slots[slot] == server.cluster.myself &&
+ n != server.cluster.myself)
+ {
+ int numkeys;
+ robj **keys;
+
+ keys = zmalloc(sizeof(robj*)*1);
+ numkeys = GetKeysInSlot(slot, keys, 1);
+ zfree(keys);
+ if (numkeys == 0) {
+ addReplyErrorFormat(c, "Can't assign hashslot %d to a different node while I still hold keys for this hash slot.", slot);
+ return;
+ }
+ }
+ /* If this node was the slot owner and the slot was marked as
+ * migrating, assigning the slot to another node will clear
+ * the migratig status. */
+ if (server.cluster.slots[slot] == server.cluster.myself &&
+ server.cluster.migrating_slots_to[slot])
+ server.cluster.migrating_slots_to[slot] = NULL;
+
+ clusterDelSlot(slot);
+ clusterAddSlot(n,slot);
} else {
addReplyError(c,"Invalid CLUSTER SETSLOT action or number of arguments");
+ return;
}
clusterSaveConfigOrDie();
addReply(c,shared.ok);
long ttl;
/* Make sure this key does not already exist here... */
- if (dbExists(c->db,c->argv[1])) {
+ if (lookupKeyWrite(c->db,c->argv[1]) != NULL) {
addReplyError(c,"Target key name is busy.");
return;
}
/* Return the pointer to the cluster node that is able to serve the query
* as all the keys belong to hash slots for which the node is in charge.
*
- * If keys in query spawn multiple nodes NULL is returned. */
-clusterNode *getNodeByQuery(redisClient *c, struct redisCommand *cmd, robj **argv, int argc, int *hashslot) {
+ * If the returned node should be used only for this request, the *ask
+ * integer is set to '1', otherwise to '0'. This is used in order to
+ * let the caller know if we should reply with -MOVED or with -ASK.
+ *
+ * If the request contains more than a single key NULL is returned,
+ * however a request with more then a key argument where the key is always
+ * the same is valid, like in: RPOPLPUSH mylist mylist.*/
+clusterNode *getNodeByQuery(redisClient *c, struct redisCommand *cmd, robj **argv, int argc, int *hashslot, int *ask) {
clusterNode *n = NULL;
+ robj *firstkey = NULL;
multiState *ms, _ms;
multiCmd mc;
- int i;
+ int i, slot = 0;
/* We handle all the cases as if they were EXEC commands, so we have
* a common code path for everything */
if (!(c->flags & REDIS_MULTI)) return server.cluster.myself;
ms = &c->mstate;
} else {
- /* Create a fake Multi State structure, with just one command */
+ /* In order to have a single codepath create a fake Multi State
+ * structure if the client is not in MULTI/EXEC state, this way
+ * we have a single codepath below. */
ms = &_ms;
_ms.commands = &mc;
_ms.count = 1;
mc.cmd = cmd;
}
+ /* Check that all the keys are the same key, and get the slot and
+ * node for this key. */
for (i = 0; i < ms->count; i++) {
struct redisCommand *mcmd;
robj **margv;
margv = ms->commands[i].argv;
keyindex = getKeysFromCommand(mcmd,margv,margc,&numkeys,
- REDIS_GETKEYS_PRELOAD);
+ REDIS_GETKEYS_ALL);
for (j = 0; j < numkeys; j++) {
- int slot = keyHashSlot((char*)margv[keyindex[j]]->ptr,
- sdslen(margv[keyindex[j]]->ptr));
- struct clusterNode *slotnode;
-
- slotnode = server.cluster.slots[slot];
- if (hashslot) *hashslot = slot;
- /* Node not assigned? (Should never happen actually
- * if we reached this function).
- * Different node than the previous one?
- * Return NULL, the cluster can't serve multi-node requests */
- if (slotnode == NULL || (n && slotnode != n)) {
- getKeysFreeResult(keyindex);
- return NULL;
+ if (firstkey == NULL) {
+ /* This is the first key we see. Check what is the slot
+ * and node. */
+ firstkey = margv[keyindex[j]];
+
+ slot = keyHashSlot((char*)firstkey->ptr, sdslen(firstkey->ptr));
+ n = server.cluster.slots[slot];
+ redisAssert(n != NULL);
} else {
- n = slotnode;
+ /* If it is not the first key, make sure it is exactly
+ * the same key as the first we saw. */
+ if (!equalStringObjects(firstkey,margv[keyindex[j]])) {
+ decrRefCount(firstkey);
+ getKeysFreeResult(keyindex);
+ return NULL;
+ }
}
}
getKeysFreeResult(keyindex);
}
- return (n == NULL) ? server.cluster.myself : n;
+ if (ask) *ask = 0; /* This is the default. Set to 1 if needed later. */
+ /* No key at all in command? then we can serve the request
+ * without redirections. */
+ if (n == NULL) return server.cluster.myself;
+ if (hashslot) *hashslot = slot;
+ /* This request is about a slot we are migrating into another instance?
+ * Then we need to check if we have the key. If we have it we can reply.
+ * If instead is a new key, we pass the request to the node that is
+ * receiving the slot. */
+ if (n == server.cluster.myself &&
+ server.cluster.migrating_slots_to[slot] != NULL)
+ {
+ if (lookupKeyRead(&server.db[0],firstkey) == NULL) {
+ if (ask) *ask = 1;
+ return server.cluster.migrating_slots_to[slot];
+ }
+ }
+ /* Handle the case in which we are receiving this hash slot from
+ * another instance, so we'll accept the query even if in the table
+ * it is assigned to a different node. */
+ if (server.cluster.importing_slots_from[slot] != NULL)
+ return server.cluster.myself;
+ /* It's not a -ASK case. Base case: just return the right node. */
+ return n;
}
projects / redis.git / blobdiff