intrusive_ptr<DocumentSource> DocumentSourceProject::createFromBson(
BSONElement elem,
const intrusive_ptr<ExpressionContext> &pExpCtx) {
/* validate */
uassert(15969, str::stream() << projectName <<
" specification must be an object",
elem.type() == Object);
Expression::ObjectCtx objectCtx(
Expression::ObjectCtx::DOCUMENT_OK
| Expression::ObjectCtx::TOP_LEVEL
| Expression::ObjectCtx::INCLUSION_OK
);
VariablesIdGenerator idGenerator;
VariablesParseState vps(&idGenerator);
intrusive_ptr<Expression> parsed = Expression::parseObject(elem.Obj(), &objectCtx, vps);
ExpressionObject* exprObj = dynamic_cast<ExpressionObject*>(parsed.get());
massert(16402, "parseObject() returned wrong type of Expression", exprObj);
uassert(16403, "$projection requires at least one output field", exprObj->getFieldCount());
intrusive_ptr<DocumentSourceProject> pProject(new DocumentSourceProject(pExpCtx, exprObj));
pProject->_variables.reset(new Variables(idGenerator.getIdCount()));
BSONObj projectObj = elem.Obj();
pProject->_raw = projectObj.getOwned();
return pProject;
}
intrusive_ptr<DocumentSource> DocumentSourceProject::createFromBson(
BSONElement elem,
const intrusive_ptr<ExpressionContext> &pExpCtx) {
/* validate */
uassert(15969, str::stream() << projectName <<
" specification must be an object",
elem.type() == Object);
Expression::ObjectCtx objectCtx(
Expression::ObjectCtx::DOCUMENT_OK
| Expression::ObjectCtx::TOP_LEVEL
| Expression::ObjectCtx::INCLUSION_OK
);
VariablesIdGenerator idGenerator;
VariablesParseState vps(&idGenerator);
intrusive_ptr<Expression> parsed = Expression::parseObject(elem.Obj(), &objectCtx, vps);
ExpressionObject* exprObj = dynamic_cast<ExpressionObject*>(parsed.get());
massert(16402, "parseObject() returned wrong type of Expression", exprObj);
uassert(16403, "$projection requires at least one output field", exprObj->getFieldCount());
intrusive_ptr<DocumentSourceProject> pProject(new DocumentSourceProject(pExpCtx, exprObj));
pProject->_variables.reset(new Variables(idGenerator.getIdCount()));
BSONObj projectObj = elem.Obj();
pProject->_raw = projectObj.getOwned(); // probably not necessary, but better to be safe
#if defined(_DEBUG)
if (exprObj->isSimple()) {
set<string> deps;
vector<string> path;
exprObj->addDependencies(deps, &path);
pProject->_simpleProjection.init(depsToProjection(deps));
}
#endif
return pProject;
}
