void ProjectionSpecValidator::parseElement(const BSONElement& elem, const FieldPath& pathToElem) {
if (elem.type() == BSONType::Object) {
parseNestedObject(elem.Obj(), pathToElem);
} else {
ensurePathDoesNotConflictOrThrow(pathToElem.fullPath());
}
}
void ExclusionNode::excludePath(FieldPath path) {
if (path.getPathLength() == 1) {
_excludedFields.insert(path.fullPath());
return;
}
addOrGetChild(path.getFieldName(0))->excludePath(path.tail());
}
void ProjectionNode::addProjectionForPath(const FieldPath& path) {
if (path.getPathLength() == 1) {
_projectedFields.insert(path.fullPath());
return;
}
// FieldPath can't be empty, so it is safe to obtain the first path component here.
addOrGetChild(path.getFieldName(0).toString())->addProjectionForPath(path.tail());
}
void ProjectionNode::addExpressionForPath(const FieldPath& path,
boost::intrusive_ptr<Expression> expr) {
// If the computed fields policy is 'kBanComputedFields', we should never reach here.
invariant(_policies.computedFieldsPolicy == ComputedFieldsPolicy::kAllowComputedFields);
if (path.getPathLength() == 1) {
auto fieldName = path.fullPath();
_expressions[fieldName] = expr;
_orderToProcessAdditionsAndChildren.push_back(fieldName);
return;
}
// FieldPath can't be empty, so it is safe to obtain the first path component here.
addOrGetChild(path.getFieldName(0).toString())->addExpressionForPath(path.tail(), expr);
}
void ProjectionSpecValidator::parseNestedObject(const BSONObj& thisLevelSpec,
const FieldPath& prefix) {
if (thisLevelSpec.isEmpty()) {
uasserted(
40180,
str::stream() << "an empty object is not a valid value. Found empty object at path "
<< prefix.fullPath());
}
for (auto&& elem : thisLevelSpec) {
auto fieldName = elem.fieldNameStringData();
if (fieldName[0] == '$') {
// This object is an expression specification like {$add: [...]}. It will be parsed
// into an Expression later, but for now, just track that the prefix has been
// specified and skip it.
if (thisLevelSpec.nFields() != 1) {
uasserted(40181,
str::stream() << "an expression specification must contain exactly "
"one field, the name of the expression. Found "
<< thisLevelSpec.nFields()
<< " fields in "
<< thisLevelSpec.toString()
<< ", while parsing object "
<< _rawObj.toString());
}
ensurePathDoesNotConflictOrThrow(prefix.fullPath());
continue;
}
if (fieldName.find('.') != std::string::npos) {
uasserted(40183,
str::stream() << "cannot use dotted field name '" << fieldName
<< "' in a sub object: "
<< _rawObj.toString());
}
parseElement(elem, FieldPath::getFullyQualifiedPath(prefix.fullPath(), fieldName));
}
}