Status ChunkManagerTargeter::targetUpdate( const BatchedUpdateDocument& updateDoc,
vector<ShardEndpoint*>* endpoints ) const {
//
// Update targeting may use either the query or the update. This is to support save-style
// updates, of the form:
//
// coll.update({ _id : xxx }, { _id : xxx, shardKey : 1, foo : bar }, { upsert : true })
//
// Because drivers do not know the shard key, they can't pull the shard key automatically
// into the query doc, and to correctly support upsert we must target a single shard.
//
// The rule is simple - If the update is replacement style (no '$set'), we target using the
// update. If the update is replacement style, we target using the query.
//
BSONObj query = updateDoc.getQuery();
BSONObj updateExpr = updateDoc.getUpdateExpr();
UpdateType updateType = getUpdateExprType( updateDoc.getUpdateExpr() );
if ( updateType == UpdateType_Unknown ) {
return Status( ErrorCodes::UnsupportedFormat,
stream() << "update document " << updateExpr
<< " has mixed $operator and non-$operator style fields" );
}
BSONObj targetedDoc = updateType == UpdateType_OpStyle ? query : updateExpr;
bool exactShardKeyQuery = false;
if ( _manager ) {
//
// Sharded collections have the following futher requirements for targeting:
//
// Upserts must be targeted exactly by shard key.
// Non-multi updates must be targeted exactly by shard key *or* exact _id.
//
exactShardKeyQuery = _manager->hasTargetableShardKey(targetedDoc);
if ( updateDoc.getUpsert() && !exactShardKeyQuery ) {
return Status( ErrorCodes::ShardKeyNotFound,
stream() << "upsert " << updateDoc.toBSON()
<< " does not contain shard key for pattern "
<< _manager->getShardKey().key() );
}
bool exactIdQuery = isExactIdQuery( updateDoc.getQuery() );
if ( !updateDoc.getMulti() && !exactShardKeyQuery && !exactIdQuery ) {
return Status( ErrorCodes::ShardKeyNotFound,
stream() << "update " << updateDoc.toBSON()
<< " does not contain _id or shard key for pattern "
<< _manager->getShardKey().key() );
}
// Track autosplit stats for sharded collections
// Note: this is only best effort accounting and is not accurate.
if ( exactShardKeyQuery ) {
ChunkPtr chunk = _manager->findChunkForDoc(targetedDoc);
_stats->chunkSizeDelta[chunk->getMin()] +=
( query.objsize() + updateExpr.objsize() );
}
}
Status result = Status::OK();
if (exactShardKeyQuery) {
// We can't rely on our query targeting to be exact
ShardEndpoint* endpoint = NULL;
result = targetShardKey(targetedDoc, &endpoint);
endpoints->push_back(endpoint);
invariant(result.isOK());
invariant(NULL != endpoint);
}
else {
result = targetQuery(targetedDoc, endpoints);
}
return result;
}
Status ChunkManagerTargeter::targetUpdate(OperationContext* txn,
const BatchedUpdateDocument& updateDoc,
vector<ShardEndpoint*>* endpoints) const {
//
// Update targeting may use either the query or the update. This is to support save-style
// updates, of the form:
//
// coll.update({ _id : xxx }, { _id : xxx, shardKey : 1, foo : bar }, { upsert : true })
//
// Because drivers do not know the shard key, they can't pull the shard key automatically
// into the query doc, and to correctly support upsert we must target a single shard.
//
// The rule is simple - If the update is replacement style (no '$set'), we target using the
// update. If the update is replacement style, we target using the query.
//
// If we have the exact shard key in either the query or replacement doc, we target using
// that extracted key.
//
BSONObj query = updateDoc.getQuery();
BSONObj updateExpr = updateDoc.getUpdateExpr();
UpdateType updateType = getUpdateExprType(updateDoc.getUpdateExpr());
if (updateType == UpdateType_Unknown) {
return Status(ErrorCodes::UnsupportedFormat,
stream() << "update document " << updateExpr
<< " has mixed $operator and non-$operator style fields");
}
BSONObj shardKey;
if (_manager) {
//
// Sharded collections have the following futher requirements for targeting:
//
// Upserts must be targeted exactly by shard key.
// Non-multi updates must be targeted exactly by shard key *or* exact _id.
//
// Get the shard key
if (updateType == UpdateType_OpStyle) {
// Target using the query
StatusWith<BSONObj> status =
_manager->getShardKeyPattern().extractShardKeyFromQuery(query);
// Bad query
if (!status.isOK())
return status.getStatus();
shardKey = status.getValue();
} else {
// Target using the replacement document
shardKey = _manager->getShardKeyPattern().extractShardKeyFromDoc(updateExpr);
}
//
// Extra sharded update validation
//
if (updateDoc.getUpsert()) {
// Sharded upserts *always* need to be exactly targeted by shard key
if (shardKey.isEmpty()) {
return Status(ErrorCodes::ShardKeyNotFound,
stream() << "upsert " << updateDoc.toBSON()
<< " does not contain shard key for pattern "
<< _manager->getShardKeyPattern().toString());
}
// Also check shard key size on upsert
Status status = ShardKeyPattern::checkShardKeySize(shardKey);
if (!status.isOK())
return status;
}
// Validate that single (non-multi) sharded updates are targeted by shard key or _id
if (!updateDoc.getMulti() && shardKey.isEmpty() && !isExactIdQuery(updateDoc.getQuery())) {
return Status(ErrorCodes::ShardKeyNotFound,
stream() << "update " << updateDoc.toBSON()
<< " does not contain _id or shard key for pattern "
<< _manager->getShardKeyPattern().toString());
}
}
// Target the shard key, query, or replacement doc
if (!shardKey.isEmpty()) {
// We can't rely on our query targeting to be exact
ShardEndpoint* endpoint = NULL;
Status result =
targetShardKey(txn, shardKey, (query.objsize() + updateExpr.objsize()), &endpoint);
endpoints->push_back(endpoint);
return result;
} else if (updateType == UpdateType_OpStyle) {
return targetQuery(query, endpoints);
} else {
return targetDoc(updateExpr, endpoints);
}
}