Crie uma coleção de
counters com propriedades value e collection {
"name": "counters",
"base": "PersistedModel",
"idInjection": true,
"options": {
"validateUpsert": true
},
"properties": {
"type": "number",
"collection": "string"
},
"validations": [],
"relations": {},
"acls": [
{
"accessType": "*",
"principalType": "ROLE",
"principalId": "$everyone",
"permission": "ALLOW"
}
],
"methods": []
}
Agora supondo que seu nome de coleção de incremento automático
tweets . Insira este valor em
counters . {
"value" : 0,
"collection" : "tweet"
}
tweet.observe('before save', function (ctx, next) {
var app = ctx.Model.app;
//Apply this hooks for save operation only..
if(ctx.isNewInstance){
//suppose my datasource name is mongodb
var mongoDb = app.dataSources.mongodb;
var mongoConnector = app.dataSources.mongodb.connector;
mongoConnector.collection("counters").findAndModify({collection: 'tweet'}, [['_id','asc']], {$inc: { value: 1 }}, {new: true}, function(err, sequence) {
if(err) {
throw err;
} else {
// Do what I need to do with new incremented value sequence.value
//Save the tweet id with autoincrement..
ctx.instance.id = sequence.value.value;
next();
} //else
});
} //ctx.isNewInstance
else{
next();
}
}); //Observe before save..
