Handling Documents that do not have ObjectID

[mgd216]

I have a program that is storing documents in MongoDB, but the program is creating it's own object ID (which is just a UUID). See example documents:

{ "_id" : "e5e781f9-2947-4198-adca-f4d452e98c1a", "isDone" : false, "description" : "New Task" }
{ "_id" : "07cea259-f333-4836-a53f-644d2428a382", "isDone" : false, "description" : "New Task" }
{ "_id" : "1dcf6de5-c634-44c4-b5d9-9e349612ed46", "isDone" : false, "description" : "New Task" }
{ "_id" : "dfd31230-4293-4539-aa55-292297474ec4", "isDone" : false, "description" : "New Task" }

When trying to pull these documents through mongodb-rest, I receive the following error:

node.js:178
throw e; // process.nextTick error, or 'error' event on first tick
^
TypeError: Object e5e781f9-2947-4198-adca-f4d452e98c1a has no method 'toHexString'
at Object.flavorize (/usr/local/lib/node/.npm/mongodb-rest/0.6.7/package/lib/util.js:22:25)
at /usr/local/lib/node/.npm/mongodb-rest/0.6.7/package/lib/rest.js:50:32
at Array.forEach (native)
at /usr/local/lib/node/.npm/mongodb-rest/0.6.7/package/lib/rest.js:49:18
at /usr/local/lib/node/.npm/mongodb/0.9.2/package/lib/mongodb/cursor.js:122:15
at /usr/local/lib/node/.npm/mongodb/0.9.2/package/lib/mongodb/cursor.js:167:11
at /usr/local/lib/node/.npm/mongodb/0.9.2/package/lib/mongodb/cursor.js:467:28
at [object Object].close (/usr/local/lib/node/.npm/mongodb/0.9.2/package/lib/mongodb/cursor.js:625:17)
at [object Object].nextObject (/usr/local/lib/node/.npm/mongodb/0.9.2/package/lib/mongodb/cursor.js:467:10)
at Array. (/usr/local/lib/node/.npm/mongodb/0.9.2/package/lib/mongodb/cursor.js:161:12)

On line 21 of the /lib/util.js package, a suggestion would be to put another 'if' statement to check if the _id is a Mongo ObjectID or just a string. Something like:

if (id == ObjectID) {
doc._id = doc._id.toHexString();
} else {
// leave doc._id alone
}

Just a suggestion, this could be a rare case since most people let Mongo (or the driver) create the ObjectID. This just happens where the project I'm on, I'm given a unique ID that is mapped to other data sources outside of Mongo via this UUID.

Great work, thanks.

Matt

[samyakbhuta]

+1 to mgd216,
Here it is assumed that the _id would be always going to be of BSON type ObjectID, which is false assumption. The assumption is made at following links, and other places as well.

• https://github.com/tdegrunt/mongodb-rest/blob/master/lib/rest.js#L23
• https://github.com/tdegrunt/mongodb-rest/blob/master/lib/rest.js#L91
• https://github.com/tdegrunt/mongodb-rest/blob/master/lib/rest.js#L109

Guess, one should be able to dictate using config.js ( or mongodb-rest should be able to do a smart guess) as what is the BSON type for _id field. E.g when it comes to uuid as values for _id, the BSON Binary type with subtype as UUID should be used ( See http://bsonspec.org/#/specification )

Also, node-mongodb-native already provide the support for various types. See https://github.com/christkv/node-mongodb-native/blob/master/examples/types.js#L30 and https://github.com/christkv/node-mongodb-native/blob/master/external-libs/bson/binary.cc#L21.

Please, also see the discussion regarding this issue at http://groups.google.com/group/node-mongodb-native/browse_thread/thread/73e0a02b5dd08102.

@mgd216, any specific reason why you don't want to store UUIDs as BSON Binary type with subtype UUID ? Why you have choose BSON type string to store them, it will occupy twice the space that too with indexing overhead.

[samyakbhuta]

Also, at https://github.com/tdegrunt/mongodb-rest/blob/master/lib/rest.js#L74 assuming that the _id would have equivalent hex string is not helpful for anybody who is dealing with BSON types other than ObjectIds.