How to generate simple schema from database in meteor - json

Question

How can we generate a schema from the database in meteor app.
I want to generate multiple schemas from each database entry.
The DB used is Mongo DB.
This schema will be used later to generate a form.
I am using autoform to generate a form.
[1: http://autoform.meteor.com]

Answer 1

I've written a small script that you can run in mongo to reverse engineer an existing (flat) collection.
/*
** SimpleSchema definition generator
**
** This will reverse engineer a flat collection
** only at this point. If you improve this,
** please share: {"email-left": "timstew", "at":"#", "email-right": "gmail.com"}
**
*/
var schemaName = "publisherSchema"; // Name you want to give to your simple schema
var collectionName = "publishers"; // mongodb collection name (not including 'db.')
var sampleID = "54c00f0d2b21500370a2e4c4"; // _id of a good representative document
// OK, that's all the info we need - Let's get started!
var message = eval("db." + collectionName + ".findOne({_id:\"" + sampleID +"\"})");
var count = 0;
// Hack because I can't figure out how to find out how many fields are in
var numKeys = 0;
for(var key in message) {numKeys += 1}
var index = 0;
for (var key in message) {
if (index == 0) {
print(schemaName + " = new SimpleSchema({");
}
print("\t" + key + ": {");
print("\t\ttype: " + toProper(eval("typeof db." + collectionName + ".findOne({_id:\"" + sampleID + "\"})." + key)) + ",");
print("\t\tlabel: \"" + toProper(key) + "\"");
if (index == numKeys-1) {
print("\t\t}");
print("\t})");
} else {
print("\t\t},");
}
index += 1;
}
function toProper(str)
{
return str.replace(/\w\S*/g, function(txt){return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();});
}

Answer 2

MongoDB is a document database, which doesn't require a schema. All you need to do is declare collections in Meteor
If you want to be strict about the document structure, check out https://github.com/aldeed/meteor-collection2 (meteor add aldeed:collection2)
I've recently explained Meteor collections and schemas here.
If you want to read the schema from a collection, you can simply access it via collectionName.simpleSchema(). For your purpose you can take this schema and convert it into your desired structure (or exclude certain configured fields).