MongoDB - Whats wrong with how I create index? - node.js

Question

I am trying to use Mongo's GeoSpatial features to locate documents based on coordinates.
I need to create indexes for it to work - but it seems like I can't get the index created? Can you help?
I'll walk through what I have so far.
//User saves the location using a PUT Command.
props.updateBandLocation({
geometry: {
type: "Point",
coordinates: [ lat, lon ]
}
})
Here is the route that puts it in the database. I try to get the index created here.
router.put('/:id', (req, res) => {
quoteGenerator.findByIdAndUpdate({_id: req.params.id}, req.body).then(() => {
quoteGenerator.findOne({_id: req.params.id}).then(generator => res.send(generator))
quoteGenerator.createIndex( { bandLocation: "2dsphere" } )
})
})
The indexing throws an error in my terminal but it creates the location anyways. Here it is in the database.
//How the query looks in the database
"bandLocation": {
"geometry": {
"type": "Point",
"coordinates": [
32.96179,
-96.82916850000001
]
}
},
Lastly, I am trying to get all the documents near a point using this route.
router.get('/allbands/:lat/:lng', (req, res) => {
quoteGenerator.find(
{
bandLocation:
{ $near: {
$geometry: {
type : "Point",
coordinates : [-req.params.lng, +req.params.lat],
}
}
}
}
).then(bands => res.json(bands))
});
Thanks for any help you have to offer!
Here is my schema --
//Create GeoSchema
const GeoSchema = new Schema({
geometry: {
type: {
type: String,
default: "Point",
index: "2dsphere",
},
coordinates: {
type: [Number],
},
}
})
//Create Schema - Band
const AutoQuoteGeneratorSchema = new Schema({
baseCost: {
type: Number
},
mainDate: {
type: Object
},
quoteGenerator: {
type: Array,
required: true,
},
userId: {
type: String,
required: true,
},
type: {
type: String,
required: true,
},
bandName: {
type: String,
required: true,
},
bandBio: {
type: String,
required: true,
},
bandLocation: GeoSchema,
bandTour: {
type: Array,
required: true,
},
bandGenre: {
type: String,
required: true,
},
youtube: {
type: Array,
required: true,
},
published: {
type: Boolean,
required: true,
},
posts: {
type: Array,
required: true,
},
});

Answer 1

Ok so from what i can see we have a couple of problems:
Structure:
From the 2dsphere index docs:
The 2dsphere index supports data stored as GeoJSON objects and legacy coordinate pairs
What type are GeoJSON objects?, they're { type: <GeoJSON type> , coordinates: <coordinates> }
And what type are legacy coordinates pairs? they're in the form of: [<longitude>, <latitude> ] or { <field1>: <x>, <field2>: <y> }
So we can see bandLocation is neither, you need to use
quoteGenerator.createIndex( { "bandLocation.geometry": "2dsphere" } )
Your Coordinates are in the wrong order, You need to specify in the order of longitude then latitude. The valid range of latitude in degrees is -90 and +90. Your value of latitude of -96 is out of range.
So change your document to [-96.82916850000001, 32.96179].
Now we just need to adjust your query:
quoteGenerator.find({
"bandLocation.geometry":
{ $near: {
$geometry: {
type : "Point",
coordinates : [-req.params.lng, +req.params.lat],
}
}
}
})
** Another thing that pops up is that you create (try to create) an index every time there's a function call when in-fact you should only do it once. it should not be a part of your code. Now this won't throw an error but it's redundant as Mongo auto index documents on changes / inserts.