BSONObj UpdateStage::applyUpdateOpsForInsert(OperationContext* opCtx,
const CanonicalQuery* cq,
const BSONObj& query,
UpdateDriver* driver,
mutablebson::Document* doc,
bool isInternalRequest,
const NamespaceString& ns,
bool enforceOkForStorage,
UpdateStats* stats) {
// 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->setInsert(true);
FieldRefSet immutablePaths;
if (!isInternalRequest) {
auto immutablePathsVector = getImmutableFields(opCtx, ns);
if (immutablePathsVector) {
immutablePaths.fillFrom(
transitional_tools_do_not_use::unspool_vector(*immutablePathsVector));
}
}
immutablePaths.keepShortest(&idFieldRef);
if (cq) {
uassertStatusOK(driver->populateDocumentWithQueryFields(*cq, immutablePaths, *doc));
if (driver->isDocReplacement())
stats->fastmodinsert = true;
} else {
fassert(17354, CanonicalQuery::isSimpleIdQuery(query));
BSONElement idElt = query[idFieldName];
fassert(17352, doc->root().appendElement(idElt));
}
// Apply the update modifications here. Do not validate for storage, since we will validate the
// entire document after the update. However, we ensure that no immutable fields are updated.
const bool validateForStorage = false;
if (isInternalRequest) {
immutablePaths.clear();
}
Status updateStatus = driver->update(StringData(), doc, validateForStorage, immutablePaths);
if (!updateStatus.isOK()) {
uasserted(16836, updateStatus.reason());
}
// Ensure _id exists and is first
auto idAndFirstStatus = ensureIdFieldIsFirst(doc);
if (idAndFirstStatus.code() == ErrorCodes::InvalidIdField) { // _id field is missing
addObjectIDIdField(doc);
} else {
uassertStatusOK(idAndFirstStatus);
}
// Validate that the object replacement or modifiers resulted in a document
// that contains all the immutable keys and can be stored if it isn't coming
// from a migration or via replication.
if (!isInternalRequest) {
if (enforceOkForStorage) {
storage_validation::storageValid(*doc);
}
checkImmutablePathsPresent(*doc, immutablePaths);
}
BSONObj newObj = doc->getObject();
if (newObj.objsize() > BSONObjMaxUserSize) {
uasserted(17420,
str::stream() << "Document to upsert is larger than " << BSONObjMaxUserSize);
}
return newObj;
}
/**
* This will verify that all updated fields are
* 1.) Valid for storage (checking parent to make sure things like DBRefs are valid)
* 2.) Compare updated immutable fields do not change values
*
* If updateFields is empty then it was replacement and/or we need to check all fields
*/
inline Status validate(const BSONObj& original,
const FieldRefSet& updatedFields,
const mb::Document& updated,
const std::vector<FieldRef*>* immutableAndSingleValueFields,
const ModifierInterface::Options& opts) {
LOG(3) << "update validate options -- "
<< " updatedFields: " << updatedFields << " immutableAndSingleValueFields.size:"
<< (immutableAndSingleValueFields ? immutableAndSingleValueFields->size() : 0)
<< " validate:" << opts.enforceOkForStorage;
// 1.) Loop through each updated field and validate for storage
// and detect immutable field updates
// The set of possibly changed immutable fields -- we will need to check their vals
FieldRefSet changedImmutableFields;
// Check to see if there were no fields specified or if we are not validating
// The case if a range query, or query that didn't result in saved fields
if (updatedFields.empty() || !opts.enforceOkForStorage) {
if (opts.enforceOkForStorage) {
// No specific fields were updated so the whole doc must be checked
Status s = storageValid(updated, true);
if (!s.isOK())
return s;
}
// Check all immutable fields
if (immutableAndSingleValueFields)
changedImmutableFields.fillFrom(*immutableAndSingleValueFields);
} else {
// TODO: Change impl so we don't need to create a new FieldRefSet
// -- move all conflict logic into static function on FieldRefSet?
FieldRefSet immutableFieldRef;
if (immutableAndSingleValueFields)
immutableFieldRef.fillFrom(*immutableAndSingleValueFields);
FieldRefSet::const_iterator where = updatedFields.begin();
const FieldRefSet::const_iterator end = updatedFields.end();
for (; where != end; ++where) {
const FieldRef& current = **where;
// Find the updated field in the updated document.
mutablebson::ConstElement newElem = updated.root();
size_t currentPart = 0;
while (newElem.ok() && currentPart < current.numParts())
newElem = newElem[current.getPart(currentPart++)];
// newElem might be missing if $unset/$renamed-away
if (newElem.ok()) {
// Check element, and its children
Status s = storageValid(newElem, true);
if (!s.isOK())
return s;
// Check parents to make sure they are valid as well.
s = storageValidParents(newElem);
if (!s.isOK())
return s;
}
// Check if the updated field conflicts with immutable fields
immutableFieldRef.findConflicts(¤t, &changedImmutableFields);
}
}
const bool checkIdField = (updatedFields.empty() && !original.isEmpty()) ||
updatedFields.findConflicts(&idFieldRef, NULL);
// Add _id to fields to check since it too is immutable
if (checkIdField)
changedImmutableFields.keepShortest(&idFieldRef);
else if (changedImmutableFields.empty()) {
// Return early if nothing changed which is immutable
return Status::OK();
}
LOG(4) << "Changed immutable fields: " << changedImmutableFields;
// 2.) Now compare values of the changed immutable fields (to make sure they haven't)
const mutablebson::ConstElement newIdElem = updated.root()[idFieldName];
FieldRefSet::const_iterator where = changedImmutableFields.begin();
const FieldRefSet::const_iterator end = changedImmutableFields.end();
for (; where != end; ++where) {
const FieldRef& current = **where;
// Find the updated field in the updated document.
mutablebson::ConstElement newElem = updated.root();
size_t currentPart = 0;
while (newElem.ok() && currentPart < current.numParts())
newElem = newElem[current.getPart(currentPart++)];
if (!newElem.ok()) {
if (original.isEmpty()) {
// If the _id is missing and not required, then skip this check
if (!(current.dottedField() == idFieldName))
return Status(ErrorCodes::NoSuchKey,
mongoutils::str::stream() << "After applying the update, the new"
<< " document was missing the '"
<< current.dottedField()
<< "' (required and immutable) field.");
} else {
if (current.dottedField() != idFieldName)
return Status(ErrorCodes::ImmutableField,
mongoutils::str::stream()
<< "After applying the update to the document with "
<< newIdElem.toString()
<< ", the '"
<< current.dottedField()
<< "' (required and immutable) field was "
"found to have been removed --"
<< original);
}
} else {
// Find the potentially affected field in the original document.
const BSONElement oldElem = dps::extractElementAtPath(original, current.dottedField());
const BSONElement oldIdElem = original.getField(idFieldName);
// Ensure no arrays since neither _id nor shard keys can be in an array, or one.
mb::ConstElement currElem = newElem;
while (currElem.ok()) {
if (currElem.getType() == Array) {
return Status(
ErrorCodes::NotSingleValueField,
mongoutils::str::stream()
<< "After applying the update to the document {"
<< (oldIdElem.ok() ? oldIdElem.toString() : newIdElem.toString())
<< " , ...}, the (immutable) field '"
<< current.dottedField()
<< "' was found to be an array or array descendant.");
}
currElem = currElem.parent();
}
// If we have both (old and new), compare them. If we just have new we are good
if (oldElem.ok() && newElem.compareWithBSONElement(oldElem, nullptr, false) != 0) {
return Status(ErrorCodes::ImmutableField,
mongoutils::str::stream()
<< "After applying the update to the document {"
<< oldElem.toString()
<< " , ...}, the (immutable) field '"
<< current.dottedField()
<< "' was found to have been altered to "
<< newElem.toString());
}
}
}
return Status::OK();
}
BSONObj UpdateStage::transformAndUpdate(const Snapshotted<BSONObj>& oldObj, RecordId& recordId) {
const UpdateRequest* request = _params.request;
UpdateDriver* driver = _params.driver;
CanonicalQuery* cq = _params.canonicalQuery;
UpdateLifecycle* lifecycle = request->getLifecycle();
// If asked to return new doc, default to the oldObj, in case nothing changes.
BSONObj newObj = oldObj.value();
// 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. In any event,
// only enable in-place mutations if the underlying storage engine offers support for
// writing damage events.
_doc.reset(oldObj.value(),
(_collection->updateWithDamagesSupported()
? mutablebson::Document::kInPlaceEnabled
: mutablebson::Document::kInPlaceDisabled));
BSONObj logObj;
bool docWasModified = false;
Status status = Status::OK();
const bool validateForStorage = getOpCtx()->writesAreReplicated() && _enforceOkForStorage;
FieldRefSet immutablePaths;
if (getOpCtx()->writesAreReplicated() && !request->isFromMigration()) {
if (lifecycle) {
auto immutablePathsVector =
getImmutableFields(getOpCtx(), request->getNamespaceString());
if (immutablePathsVector) {
immutablePaths.fillFrom(
transitional_tools_do_not_use::unspool_vector(*immutablePathsVector));
}
}
immutablePaths.keepShortest(&idFieldRef);
}
if (!driver->needMatchDetails()) {
// If we don't need match details, avoid doing the rematch
status = driver->update(
StringData(), &_doc, validateForStorage, immutablePaths, &logObj, &docWasModified);
} else {
// If there was a matched field, obtain it.
MatchDetails matchDetails;
matchDetails.requestElemMatchKey();
dassert(cq);
verify(cq->root()->matchesBSON(oldObj.value(), &matchDetails));
string matchedField;
if (matchDetails.hasElemMatchKey())
matchedField = matchDetails.elemMatchKey();
status = driver->update(
matchedField, &_doc, validateForStorage, immutablePaths, &logObj, &docWasModified);
}
if (!status.isOK()) {
uasserted(16837, status.reason());
}
// Skip adding _id field if the collection is capped (since capped collection documents can
// neither grow nor shrink).
const auto createIdField = !_collection->isCapped();
// Ensure if _id exists it is first
status = ensureIdFieldIsFirst(&_doc);
if (status.code() == ErrorCodes::InvalidIdField) {
// Create ObjectId _id field if we are doing that
if (createIdField) {
addObjectIDIdField(&_doc);
}
} else {
uassertStatusOK(status);
}
// See if the changes were applied in place
const char* source = NULL;
const bool inPlace = _doc.getInPlaceUpdates(&_damages, &source);
if (inPlace && _damages.empty()) {
// An interesting edge case. A modifier didn't notice that it was really a no-op
// during its 'prepare' phase. That represents a missed optimization, but we still
// shouldn't do any real work. Toggle 'docWasModified' to 'false'.
//
// Currently, an example of this is '{ $push : { x : {$each: [], $sort: 1} } }' when the 'x'
// array exists and is already sorted.
docWasModified = false;
}
if (docWasModified) {
// Prepare to write back the modified document
WriteUnitOfWork wunit(getOpCtx());
RecordId newRecordId;
OplogUpdateEntryArgs args;
if (!request->isExplain()) {
invariant(_collection);
auto* css = CollectionShardingState::get(getOpCtx(), _collection->ns());
args.nss = _collection->ns();
args.uuid = _collection->uuid();
args.stmtId = request->getStmtId();
args.update = logObj;
args.criteria = css->getMetadata().extractDocumentKey(newObj);
uassert(16980,
"Multi-update operations require all documents to have an '_id' field",
!request->isMulti() || args.criteria.hasField("_id"_sd));
args.fromMigrate = request->isFromMigration();
args.storeDocOption = getStoreDocMode(*request);
if (args.storeDocOption == OplogUpdateEntryArgs::StoreDocOption::PreImage) {
args.preImageDoc = oldObj.value().getOwned();
}
}
if (inPlace) {
if (!request->isExplain()) {
newObj = oldObj.value();
const RecordData oldRec(oldObj.value().objdata(), oldObj.value().objsize());
Snapshotted<RecordData> snap(oldObj.snapshotId(), oldRec);
StatusWith<RecordData> newRecStatus = _collection->updateDocumentWithDamages(
getOpCtx(), recordId, std::move(snap), source, _damages, &args);
newObj = uassertStatusOK(std::move(newRecStatus)).releaseToBson();
}
newRecordId = recordId;
} else {
// The updates were not in place. Apply them through the file manager.
newObj = _doc.getObject();
uassert(17419,
str::stream() << "Resulting document after update is larger than "
<< BSONObjMaxUserSize,
newObj.objsize() <= BSONObjMaxUserSize);
if (!request->isExplain()) {
newRecordId = _collection->updateDocument(getOpCtx(),
recordId,
oldObj,
newObj,
true,
driver->modsAffectIndices(),
_params.opDebug,
&args);
}
}
invariant(oldObj.snapshotId() == getOpCtx()->recoveryUnit()->getSnapshotId());
wunit.commit();
// 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
// updatedRecordIds.
//
// This must be done after the wunit commits so we are sure we won't be rolling back.
if (_updatedRecordIds && (newRecordId != recordId || driver->modsAffectIndices())) {
_updatedRecordIds->insert(newRecordId);
}
}
// Only record doc modifications if they wrote (exclude no-ops). Explains get
// recorded as if they wrote.
if (docWasModified || request->isExplain()) {
_specificStats.nModified++;
}
return newObj;
}
