bool Pipeline::run(BSONObjBuilder &result, string &errmsg) {
massert(16600, "should not have an empty pipeline",
!sources.empty());
/* chain together the sources we found */
DocumentSource* prevSource = sources.front().get();
for(SourceContainer::iterator iter(sources.begin() + 1),
listEnd(sources.end());
iter != listEnd;
++iter) {
intrusive_ptr<DocumentSource> pTemp(*iter);
pTemp->setSource(prevSource);
prevSource = pTemp.get();
}
/*
Iterate through the resulting documents, and add them to the result.
We do this even if we're doing an explain, in order to capture
the document counts and other stats. However, we don't capture
the result documents for explain.
*/
if (explain) {
if (!pCtx->getInRouter())
writeExplainShard(result);
else {
writeExplainMongos(result);
}
}
else {
// the array in which the aggregation results reside
// cant use subArrayStart() due to error handling
BSONArrayBuilder resultArray;
DocumentSource* finalSource = sources.back().get();
for(bool hasDoc = !finalSource->eof(); hasDoc; hasDoc = finalSource->advance()) {
Document pDocument(finalSource->getCurrent());
/* add the document to the result set */
BSONObjBuilder documentBuilder (resultArray.subobjStart());
pDocument->toBson(&documentBuilder);
documentBuilder.doneFast();
// object will be too large, assert. the extra 1KB is for headers
uassert(16389,
str::stream() << "aggregation result exceeds maximum document size ("
<< BSONObjMaxUserSize / (1024 * 1024) << "MB)",
resultArray.len() < BSONObjMaxUserSize - 1024);
}
resultArray.done();
result.appendArray("result", resultArray.arr());
}
return true;
}
void Pipeline::run(BSONObjBuilder& result) {
/*
Iterate through the resulting documents, and add them to the result.
We do this even if we're doing an explain, in order to capture
the document counts and other stats. However, we don't capture
the result documents for explain.
*/
if (explain) {
if (!pCtx->getInRouter())
writeExplainShard(result);
else {
writeExplainMongos(result);
}
}
else {
// the array in which the aggregation results reside
// cant use subArrayStart() due to error handling
BSONArrayBuilder resultArray;
DocumentSource* finalSource = sources.back().get();
for (bool hasDoc = !finalSource->eof(); hasDoc; hasDoc = finalSource->advance()) {
Document pDocument(finalSource->getCurrent());
/* add the document to the result set */
BSONObjBuilder documentBuilder (resultArray.subobjStart());
pDocument->toBson(&documentBuilder);
documentBuilder.doneFast();
// object will be too large, assert. the extra 1KB is for headers
uassert(16389,
str::stream() << "aggregation result exceeds maximum document size ("
<< BSONObjMaxUserSize / (1024 * 1024) << "MB)",
resultArray.len() < BSONObjMaxUserSize - 1024);
}
resultArray.done();
result.appendArray("result", resultArray.arr());
}
}
bool Pipeline::run(BSONObjBuilder &result, string &errmsg,
const intrusive_ptr<DocumentSource> &pInputSource) {
/* chain together the sources we found */
DocumentSource *pSource = pInputSource.get();
for(SourceVector::iterator iter(sourceVector.begin()),
listEnd(sourceVector.end()); iter != listEnd; ++iter) {
intrusive_ptr<DocumentSource> pTemp(*iter);
pTemp->setSource(pSource);
pSource = pTemp.get();
}
/* pSource is left pointing at the last source in the chain */
/*
Iterate through the resulting documents, and add them to the result.
We do this even if we're doing an explain, in order to capture
the document counts and other stats. However, we don't capture
the result documents for explain.
We wrap all the BSONObjBuilder calls with a try/catch in case the
objects get too large and cause an exception.
*/
try {
if (explain) {
if (!pCtx->getInRouter())
writeExplainShard(result, pInputSource);
else {
writeExplainMongos(result, pInputSource);
}
}
else
{
BSONArrayBuilder resultArray; // where we'll stash the results
for(bool hasDocument = !pSource->eof(); hasDocument;
hasDocument = pSource->advance()) {
intrusive_ptr<Document> pDocument(pSource->getCurrent());
/* add the document to the result set */
BSONObjBuilder documentBuilder;
pDocument->toBson(&documentBuilder);
resultArray.append(documentBuilder.done());
}
result.appendArray("result", resultArray.arr());
}
} catch(AssertionException &ae) {
/*
If its not the "object too large" error, rethrow.
At time of writing, that error code comes from
mongo/src/mongo/bson/util/builder.h
*/
if (ae.getCode() != 13548)
throw;
/* throw the nicer human-readable error */
uassert(16029, str::stream() <<
"aggregation result exceeds maximum document size limit ("
<< (BSONObjMaxUserSize / (1024 * 1024)) << "MB)",
false);
}
return true;
}
