Ember Data: Using "links" on JSON payload for hasMany relationships - json

Given two models in an app using DS.RESTAdapter:
App.Calendar = DS.Model.extend({
reservations: DS.hasMany("reservation", { async: true })
});
App.Reservation = DS.Model.extend({
date: DS.attr("date"),
calendar: DS.belongsTo("calendar")
});
And payloads such as:
/api/calendar/1:
{
"calendar": {
"id": 1,
"reservations": [],
"links": {
"reservations": "/api/calendar/1/reservations"
}
}
}
/api/calendar/1/reservations:
{
"reservations": [
{
"id": 1,
"date": "10/01/2014"
}
]
}
Why is it that the reservations array on the Calendar model isn't being lazy-loaded?

Your json shouldn't have reservations defined twice
{
"calendar": {
"id": 1,
"links": {
"reservations": "/api/calendar/1/reservations"
}
}
}

Related

Map mongo aggregation result to array

I have a mongo query that looks like this:
db.myCollection.aggregate([ {
$group: {
_id: null,
price: {
$sum: "$price"
},
inventory: {
$sum: "$inventory"
}
}
}])
Which returns
{
"_id" : null,
"price" : 26,
"inventory" : 5,
}
I would like a query which would rather return something like this:
[
{
name: "price",
amount: 26
},
{
name: "inventory",
amount: 5
}
]
EDIT:
How would I write this in Java with Spring Data? I can group and sum but don't know how to project it?
Aggregation aggregation = newAggregation(
group("$id")
.sum("price").as("price")
.sum("inventory").as("inventory")
);
You'll need to use $project. It allows us to define which fields will be returned, as well as their format.
db.myCollection.aggregate([{
$group: {
_id: null,
price: {
$sum: "$price"
},
inventory: {
$sum: "$inventory"
}
}
},
{
$project: {
_id: 0 //removes _id from result
something: [
{name: "price", amount: "$price"},
{name: "inventory", amount: "$inventory"}
]
}
}])
That will give you:
{
"something" : [
{
"name" : "price",
"amount" : 26
},
{
"name" : "inventory",
"amount" : 5
}
]
}
You can use below aggregation
db.collection.aggregate([
{ "$project": {
"data": {
"$map": {
"input": { "$objectToArray": "$$ROOT" },
"in": { "name": "$$this.k", "amount": "$$this.v" }
}
}
}},
{ "$unwind": "$data" },
{ "$replaceRoot": { "newRoot": "$data" }},
{ "$match": { "amount": { "$ne": null }}
}
])

Angular - convert HAL to JSON

The following service extracts category objects from a REST service which returns them in HAL format. Now I try to convert that response into JSON. For that I searched and tried different solutions, e.g. chariotsolutions or so. Some are based on Response from '#angular/http' which is deprecated and which I cannot make work.
How can I do the conversion?
import { Injectable } from '#angular/core';
import { HttpClient, HttpHeaders } from '#angular/common/http';
import { Observable } from 'rxjs/Rx';
import { of } from 'rxjs/observable/of';
import 'rxjs/Rx';
import 'rxjs/add/operator/map';
import { Category } from './category';
#Injectable()
export class CategoryService {
private categoriesUrl = 'http://localhost:8080/account/categories';
constructor(private http: HttpClient) { }
getCategories(): Observable<Category[]> {
return this.http.get<Category[]>(this.categoriesUrl);
}
}
The response as HAL
{
"_embedded": {
"categories": [
{
"id": 1,
"name": "hardware",
"description": "comprises all computer hardware",
"level": "FIRST",
"_links": {
"self": {
"href": "http://localhost:8080/account/categories/1"
},
"categoryEntity": {
"href": "http://localhost:8080/account/categories/1"
}
}
},
{
"id": 2,
"name": "hardware_notebook",
"description": "all notebooks",
"level": "SECOND",
"_links": {
"self": {
"href": "http://localhost:8080/account/categories/2"
},
"categoryEntity": {
"href": "http://localhost:8080/account/categories/2"
}
}
}
]
},
"_links": {
"self": {
"href": "http://localhost:8080/account/categories{?page,size,sort}",
"templated": true
},
"profile": {
"href": "http://localhost:8080/account/profile/categories"
}
},
"page": {
"size": 20,
"totalElements": 8,
"totalPages": 1,
"number": 0
}
}
getCategories(): Observable<Category[]> {
return this.http.get<Category[]>(this.categoriesUrl)
.map((result:any)=>{
console.log(result); //<--it's an object
//result={"_embedded": {"categories": [..]..}
return result._embedded.categories; //just return "categories"
});
}
With Rjxs 6.0 we must use pipe(map)
getCategories(): Observable<Category[]> {
return this.http.get<Category[]>(this.categoriesUrl).pipe(
map((result:any)=>{
console.log(result); //<--it's an object
//result={"_embedded": {"categories": [..]..}
return result._embedded.categories; //just return "categories"
}));
}
Try following:
getCategories(): Observable<Category[]> {
return this.http.get<Category[]>(this.categoriesUrl).map((response)=>{
return response;
})
}

Add some data in aggregation with $match in MongoDb

I am using mongoDb, restheart and also new in these technologies. I want to add one more field in aggregation. So my exist aggregation working fine. I am sharing aggregation
Aggregation:
aggrs: [{
type: "pipeline",
uri: "by_time",
stages: [{
_$match: {
bus::destination: {
_$in: {
_$var: "stands"
}
},
bus::eta: {
_$gte: {
_$var: "dateFrom"
},
_$lte: {
_$var: "dateTo"
}
}
}
},
]
}]
Json Data:
{
_id: "1938378_32323",
bus: {
valid: true,
eta: {
$date: 1500661200000
},
busDate: {
$date: 1500595200000
},
etd: {
$date: 1500661200000
},
origin: "kalu",
destination: "cell",
},
apose: false
}
Above aggregation working fine, But I want to add "apose" in aggregation. So I have implemented this code for aggregation.
stages: [{
_$match: {
bus::destination: {
_$in: {
_$var: "stands"
}
},
bus::eta: {
_$gte: {
_$var: "dateFrom"
},
_$lte: {
_$var: "dateTo"
}
},
"apose": {
"_$eq": {
"_$var": "opposit"
}
}
}
},
]
But When I hit this aggregation, I got only
{"_embedded":[],"_size":0,"_total_pages":0,"_returned":0}
My hitting url is
http:...abc.../_aggrs/by_time?avars={"stands":["KALU","MAL","SALU"],"dateFrom":{"$date":"2007-12-21T01:30:00Z"},"dateTo":{"$date":"2010-02-15T09:30:00Z"},"opposit":"false"}
your answer is valuable for me. Thanks

How to perform join in sails JS

I have documents of the form
challenge:
{
"name": "challenge by abdul",
"created_user_id": "1",
"game_id": "123",
"platform_id": "9857",
"amount": 30
}
game:
{
"_id": "auto_generated",
"name": "NFS",
"version": "3",
}
platform:
{
"_id": "auto_generated",
"name": "ps2",
"version": "sami"
}
I want to perform join query in sails and want result in below format
{
"name": "challenge by abdul",
"created_user_id": "1",
"game_id": "123",
"game_name":"NFS",
"platform_name": "ps2",
"platform_id": "9857",
"amount": 30
}
There is no join in Sails but populate. So you need make associations between models and populate them. Example:
// api/models/Platform.js
module.exports = {
attributes: {
name: {
type: 'string'
},
version: {
type: 'string'
},
game: {
model: 'Game',
via: 'platform'
}
}
};
// api/models/Game.js
module.exports = {
attributes: {
name: {
type: 'string'
},
version: {
type: 'string'
},
platform: {
model: 'Platform',
via: 'game'
}
}
};
You can write following code then:
// api/controllers/AnyController.js
module.exports = {
index: function(req, res) {
Game
.findOne({name: 'MY_GAME'})
.populate('platform')
.then(function(game) {
console.log(game); // Game model
console.log(game.platform); // Platform model
return game;
})
.then(res.ok)
.catch(res.negotiate);
}
};

Elasticsearch: how to store all json objects dynamically

I'm trying to store all Json objects through elasticsearch.
client.create({
index: 'index',
type: 'type',
id:"1"
body:result[0]
},function (error,response)
{
if (error)
{
console.log('elasticsearch cluster is down!');
}
else
{
console.log('All is well');
}
});
In this result[0] I'm getting my first value of a Json object but I need to store all Json objects dynamically.
The output which i'm getting is:
-> POST http://localhost:9200/index/type/1?op_type=create
{
"Name": "Martin",
"Age": "43",
"Address": "trichy"
}
<- 201
{
"_index": "index",
"_type": "type",
"_id": "1",
"_version": 4,
"created": true
}
But I need an output like this:
-> POST http://localhost:9200/index/type/1?op_type=create
{
"Name": "Martin",
"Age": "43",
"Address": "trichy"
},
{
"Name": "vel",
"Age": "23",
"Address": "chennai"
},
{
"Name": "ajay",
"Age": "23",
"Address": "chennai"
}
<- 201
{
"_index": "index",
"_type": "type",
"_id": "1",
"_version": 4,
"created": true
}
What you need is to use the bulk endpoint in order to send many documents at the same time.
The body contains two rows per document, the first row contains the index, type and id of the document and the document itself is in the next row. Rinse and repeat for each document.
client.bulk({
body: [
// action description
{ index: { _index: 'index', _type: 'type', _id: 1 } },
// the document to index
{ Name: 'Martin', Age: 43, Address: 'trichy' },
{ index: { _index: 'index', _type: 'type', _id: 2 } },
{ Name: 'vel', Age: 23, Address: 'chennai' },
{ index: { _index: 'index', _type: 'type', _id: 3 } },
{ Name: 'ajay', Age: 23, Address: 'chennai' }
]
}, function (err, resp) {
// ...
});
I suspect your result array is the JSON you get from your other question from yesterday. If so, then you can build the bulk body dynamically, like this:
var body = [];
result.forEach(function(row, id) {
body.push({ index: { _index: 'index', _type: 'type', _id: (id+1) } });
body.push(row);
});
Then you can use the body in your bulk call like this:
client.bulk({
body: body
}, function (err, resp) {
// ...
});