UpdateResult update(const UpdateRequest& request, OpDebug* opDebug) {
// Should the modifiers validate their embedded docs via okForStorage
// Only user updates should be checked. Any system or replication stuff should pass through.
// Config db docs shouldn't get checked for valid field names since the shard key can have
// a dot (".") in it.
bool shouldValidate = !(request.isFromReplication() ||
request.getNamespaceString().isConfigDB());
// TODO: Consider some sort of unification between the UpdateDriver, ModifierInterface
// and UpdateRequest structures.
UpdateDriver::Options opts;
opts.multi = request.isMulti();
opts.upsert = request.isUpsert();
opts.logOp = request.shouldUpdateOpLog();
opts.modOptions = ModifierInterface::Options( request.isFromReplication(), shouldValidate );
UpdateDriver driver( opts );
Status status = driver.parse( request.getUpdates() );
if ( !status.isOK() ) {
uasserted( 16840, status.reason() );
}
return update(request, opDebug, &driver);
}
UpdateResult update(OperationContext* txn,
Database* db,
const UpdateRequest& request,
OpDebug* opDebug) {
invariant(db);
// Explain should never use this helper.
invariant(!request.isExplain());
const NamespaceString& nsString = request.getNamespaceString();
Collection* collection = db->getCollection(txn, nsString.ns());
// The update stage does not create its own collection. As such, if the update is
// an upsert, create the collection that the update stage inserts into beforehand.
if (!collection && request.isUpsert()) {
// We have to have an exclusive lock on the db to be allowed to create the collection.
// Callers should either get an X or create the collection.
const Locker* locker = txn->lockState();
invariant(locker->isW() ||
locker->isLockHeldForMode(ResourceId(RESOURCE_DATABASE, nsString.db()),
MODE_X));
ScopedTransaction transaction(txn, MODE_IX);
Lock::DBLock lk(txn->lockState(), nsString.db(), MODE_X);
WriteUnitOfWork wuow(txn);
collection = db->createCollection(txn, nsString.ns());
invariant(collection);
if (!request.isFromReplication()) {
repl::logOp(txn,
"c",
(db->name() + ".$cmd").c_str(),
BSON("create" << (nsString.coll())));
}
wuow.commit();
}
// Parse the update, get an executor for it, run the executor, get stats out.
ParsedUpdate parsedUpdate(txn, &request);
uassertStatusOK(parsedUpdate.parseRequest());
PlanExecutor* rawExec;
uassertStatusOK(getExecutorUpdate(txn, collection, &parsedUpdate, opDebug, &rawExec));
boost::scoped_ptr<PlanExecutor> exec(rawExec);
uassertStatusOK(exec->executePlan());
return UpdateStage::makeUpdateResult(exec.get(), opDebug);
}
UpdateResult update(
OperationContext* txn,
Database* db,
const UpdateRequest& request,
OpDebug* opDebug,
UpdateDriver* driver,
CanonicalQuery* cq) {
LOG(3) << "processing update : " << request;
std::auto_ptr<CanonicalQuery> cqHolder(cq);
const NamespaceString& nsString = request.getNamespaceString();
UpdateLifecycle* lifecycle = request.getLifecycle();
Collection* collection = db->getCollection(txn, nsString.ns());
validateUpdate(nsString.ns().c_str(), request.getUpdates(), request.getQuery());
// TODO: This seems a bit circuitious.
opDebug->updateobj = request.getUpdates();
if (lifecycle) {
lifecycle->setCollection(collection);
driver->refreshIndexKeys(lifecycle->getIndexKeys());
}
Runner* rawRunner;
Status status = cq ?
getRunner(collection, cqHolder.release(), &rawRunner) :
getRunner(collection, nsString.ns(), request.getQuery(), &rawRunner, &cq);
uassert(17243,
"could not get runner " + request.getQuery().toString() + "; " + causedBy(status),
status.isOK());
// Create the runner and setup all deps.
auto_ptr<Runner> runner(rawRunner);
// Register Runner with ClientCursor
const ScopedRunnerRegistration safety(runner.get());
//
// We'll start assuming we have one or more documents for this update. (Otherwise,
// we'll fall-back to insert case (if upsert is true).)
//
// We are an update until we fall into the insert case below.
driver->setContext(ModifierInterface::ExecInfo::UPDATE_CONTEXT);
int numMatched = 0;
// If the update was in-place, we may see it again. This only matters if we're doing
// a multi-update; if we're not doing a multi-update we stop after one update and we
// won't see any more docs.
//
// For example: If we're scanning an index {x:1} and performing {$inc:{x:5}}, we'll keep
// moving the document forward and it will continue to reappear in our index scan.
// Unless the index is multikey, the underlying query machinery won't de-dup.
//
// If the update wasn't in-place we may see it again. Our query may return the new
// document and we wouldn't want to update that.
//
// So, no matter what, we keep track of where the doc wound up.
typedef unordered_set<DiskLoc, DiskLoc::Hasher> DiskLocSet;
const scoped_ptr<DiskLocSet> updatedLocs(request.isMulti() ? new DiskLocSet : NULL);
// Reset these counters on each call. We might re-enter this function to retry this
// update if we throw a page fault exception below, and we rely on these counters
// reflecting only the actions taken locally. In particlar, we must have the no-op
// counter reset so that we can meaningfully comapre it with numMatched above.
opDebug->nscanned = 0;
opDebug->nscannedObjects = 0;
opDebug->nModified = 0;
// Get the cached document from the update driver.
mutablebson::Document& doc = driver->getDocument();
mutablebson::DamageVector damages;
// Used during iteration of docs
BSONObj oldObj;
// Get first doc, and location
Runner::RunnerState state = Runner::RUNNER_ADVANCED;
uassert(ErrorCodes::NotMaster,
mongoutils::str::stream() << "Not primary while updating " << nsString.ns(),
!request.shouldCallLogOp()
|| repl::getGlobalReplicationCoordinator()->canAcceptWritesForDatabase(
nsString.db()));
while (true) {
// Get next doc, and location
DiskLoc loc;
state = runner->getNext(&oldObj, &loc);
if (state != Runner::RUNNER_ADVANCED) {
if (state == Runner::RUNNER_EOF) {
// We have reached the logical end of the loop, so do yielding recovery
break;
}
else {
uassertStatusOK(Status(ErrorCodes::InternalError,
str::stream() << " Update query failed -- "
<< Runner::statestr(state)));
}
}
// We fill this with the new locs of moved doc so we don't double-update.
if (updatedLocs && updatedLocs->count(loc) > 0) {
continue;
}
// We count how many documents we scanned even though we may skip those that are
// deemed duplicated. The final 'numMatched' and 'nscanned' numbers may differ for
// that reason.
// TODO: Do we want to pull this out of the underlying query plan?
opDebug->nscanned++;
// Found a matching document
opDebug->nscannedObjects++;
numMatched++;
// Ask the driver to apply the mods. It may be that the driver can apply those "in
// place", that is, some values of the old document just get adjusted without any
// change to the binary layout on the bson layer. It may be that a whole new
// document is needed to accomodate the new bson layout of the resulting document.
doc.reset(oldObj, mutablebson::Document::kInPlaceEnabled);
BSONObj logObj;
FieldRefSet updatedFields;
Status status = Status::OK();
if (!driver->needMatchDetails()) {
// If we don't need match details, avoid doing the rematch
status = driver->update(StringData(), &doc, &logObj, &updatedFields);
}
else {
// If there was a matched field, obtain it.
MatchDetails matchDetails;
matchDetails.requestElemMatchKey();
dassert(cq);
verify(cq->root()->matchesBSON(oldObj, &matchDetails));
string matchedField;
if (matchDetails.hasElemMatchKey())
matchedField = matchDetails.elemMatchKey();
// TODO: Right now, each mod checks in 'prepare' that if it needs positional
// data, that a non-empty StringData() was provided. In principle, we could do
// that check here in an else clause to the above conditional and remove the
// checks from the mods.
status = driver->update(matchedField, &doc, &logObj, &updatedFields);
}
if (!status.isOK()) {
uasserted(16837, status.reason());
}
// Ensure _id exists and is first
uassertStatusOK(ensureIdAndFirst(doc));
// If the driver applied the mods in place, we can ask the mutable for what
// changed. We call those changes "damages". :) We use the damages to inform the
// journal what was changed, and then apply them to the original document
// ourselves. If, however, the driver applied the mods out of place, we ask it to
// generate a new, modified document for us. In that case, the file manager will
// take care of the journaling details for us.
//
// This code flow is admittedly odd. But, right now, journaling is baked in the file
// manager. And if we aren't using the file manager, we have to do jounaling
// ourselves.
bool docWasModified = false;
BSONObj newObj;
const char* source = NULL;
bool inPlace = doc.getInPlaceUpdates(&damages, &source);
// If something changed in the document, verify that no immutable fields were changed
// and data is valid for storage.
if ((!inPlace || !damages.empty()) ) {
if (!(request.isFromReplication() || request.isFromMigration())) {
const std::vector<FieldRef*>* immutableFields = NULL;
if (lifecycle)
immutableFields = lifecycle->getImmutableFields();
uassertStatusOK(validate(oldObj,
updatedFields,
doc,
immutableFields,
driver->modOptions()) );
}
}
// Save state before making changes
runner->saveState();
if (inPlace && !driver->modsAffectIndices()) {
// If a set of modifiers were all no-ops, we are still 'in place', but there is
// no work to do, in which case we want to consider the object unchanged.
if (!damages.empty() ) {
collection->updateDocumentWithDamages( txn, loc, source, damages );
docWasModified = true;
opDebug->fastmod = true;
}
newObj = oldObj;
}
else {
// The updates were not in place. Apply them through the file manager.
// XXX: With experimental document-level locking, we do not hold the sufficient
// locks, so this would cause corruption.
fassert(18516, !useExperimentalDocLocking);
newObj = doc.getObject();
uassert(17419,
str::stream() << "Resulting document after update is larger than "
<< BSONObjMaxUserSize,
newObj.objsize() <= BSONObjMaxUserSize);
StatusWith<DiskLoc> res = collection->updateDocument(txn,
loc,
newObj,
true,
opDebug);
uassertStatusOK(res.getStatus());
DiskLoc newLoc = res.getValue();
docWasModified = true;
// If the document moved, we might see it again in a collection scan (maybe it's
// a document after our current document).
//
// If the document is indexed and the mod changes an indexed value, we might see it
// again. For an example, see the comment above near declaration of updatedLocs.
if (updatedLocs && (newLoc != loc || driver->modsAffectIndices())) {
updatedLocs->insert(newLoc);
}
}
// Restore state after modification
uassert(17278,
"Update could not restore runner state after updating a document.",
runner->restoreState(txn));
// Call logOp if requested.
if (request.shouldCallLogOp() && !logObj.isEmpty()) {
BSONObj idQuery = driver->makeOplogEntryQuery(newObj, request.isMulti());
repl::logOp(txn, "u", nsString.ns().c_str(), logObj , &idQuery,
NULL, request.isFromMigration());
}
// Only record doc modifications if they wrote (exclude no-ops)
if (docWasModified)
opDebug->nModified++;
if (!request.isMulti()) {
break;
}
// Opportunity for journaling to write during the update.
txn->recoveryUnit()->commitIfNeeded();
}
// TODO: Can this be simplified?
if ((numMatched > 0) || (numMatched == 0 && !request.isUpsert()) ) {
opDebug->nMatched = numMatched;
return UpdateResult(numMatched > 0 /* updated existing object(s) */,
!driver->isDocReplacement() /* $mod or obj replacement */,
opDebug->nModified /* number of modified docs, no no-ops */,
numMatched /* # of docs matched/updated, even no-ops */,
BSONObj());
}
//
// We haven't found any existing document so an insert is done
// (upsert is true).
//
opDebug->upsert = true;
// Since this is an insert (no docs found and upsert:true), we will be logging it
// as an insert in the oplog. We don't need the driver's help to build the
// oplog record, then. We also set the context of the update driver to the INSERT_CONTEXT.
// Some mods may only work in that context (e.g. $setOnInsert).
driver->setLogOp(false);
driver->setContext(ModifierInterface::ExecInfo::INSERT_CONTEXT);
// Reset the document we will be writing to
doc.reset();
// This remains the empty object in the case of an object replacement, but in the case
// of an upsert where we are creating a base object from the query and applying mods,
// we capture the query as the original so that we can detect immutable field mutations.
BSONObj original = BSONObj();
// Calling createFromQuery will populate the 'doc' with fields from the query which
// creates the base of the update for the inserterd doc (because upsert was true)
if (cq) {
uassertStatusOK(driver->populateDocumentWithQueryFields(cq, doc));
// Validate the base doc, as taken from the query -- no fields means validate all.
FieldRefSet noFields;
uassertStatusOK(validate(BSONObj(), noFields, doc, NULL, driver->modOptions()));
if (!driver->isDocReplacement()) {
opDebug->fastmodinsert = true;
// We need all the fields from the query to compare against for validation below.
original = doc.getObject();
}
else {
original = request.getQuery();
}
}
else {
fassert(17354, CanonicalQuery::isSimpleIdQuery(request.getQuery()));
BSONElement idElt = request.getQuery()["_id"];
original = idElt.wrap();
fassert(17352, doc.root().appendElement(idElt));
}
// Apply the update modifications and then log the update as an insert manually.
FieldRefSet updatedFields;
status = driver->update(StringData(), &doc, NULL, &updatedFields);
if (!status.isOK()) {
uasserted(16836, status.reason());
}
// Ensure _id exists and is first
uassertStatusOK(ensureIdAndFirst(doc));
// Validate that the object replacement or modifiers resulted in a document
// that contains all the immutable keys and can be stored.
if (!(request.isFromReplication() || request.isFromMigration())){
const std::vector<FieldRef*>* immutableFields = NULL;
if (lifecycle)
immutableFields = lifecycle->getImmutableFields();
// This will only validate the modified fields if not a replacement.
uassertStatusOK(validate(original,
updatedFields,
doc,
immutableFields,
driver->modOptions()) );
}
// Only create the collection if the doc will be inserted.
if (!collection) {
collection = db->getCollection(txn, request.getNamespaceString().ns());
if (!collection) {
collection = db->createCollection(txn, request.getNamespaceString().ns());
}
}
// Insert the doc
BSONObj newObj = doc.getObject();
uassert(17420,
str::stream() << "Document to upsert is larger than " << BSONObjMaxUserSize,
newObj.objsize() <= BSONObjMaxUserSize);
StatusWith<DiskLoc> newLoc = collection->insertDocument(txn,
newObj,
!request.isGod() /*enforceQuota*/);
uassertStatusOK(newLoc.getStatus());
if (request.shouldCallLogOp()) {
repl::logOp(txn, "i", nsString.ns().c_str(), newObj,
NULL, NULL, request.isFromMigration());
}
opDebug->nMatched = 1;
return UpdateResult(false /* updated a non existing document */,
!driver->isDocReplacement() /* $mod or obj replacement? */,
1 /* docs written*/,
1 /* count of updated documents */,
newObj /* object that was upserted */ );
}