I am trying to learn to react.js with hooks. I have encountered an issue with an array of objects.
Here's the code
const [stories, setStoreis] = useState(
[
{
name: "1st Story",
sid: "1",
appartmentDetails: [
{
aptName: "Master Bath",
status: "",
media: Logo,
},
{
aptName: "Master Bath",
status: "",
media: Logo,
},
],
},
{
name: "2nd Story",
sid: "2",
appartmentDetails: [
{
aptName: "Master Bath",
status: "",
media: Logo,
},
],
},
]
);
To add new Story here's what I am doing
const newStory = {
name: "3rd Story",
sid: "3",
appartmentDetails: [],
};
setStory([...stories, newStory]);
It's adding completely fine. Now I want to add appartmentDetails. How can I add appartmentDetails of specific story? Also if I want to update how to do it?
If you are working with nested data like this with immutability in mind, I'd suggest using Immer as it makes cases like this much easier. There's a use-immer hook that is very useful to this.
Edit: Codesandbox with an example of use-immer with create/update/delete on the story data.
import { useImmer } from 'use-immer';
const [stories, updateStories] = useImmer(
[
{
name: "1st Story",
sid: "1",
appartmentDetails: [
{
aptName: "Master Bath",
status: "",
media: Logo,
},
{
aptName: "Master Bath",
status: "",
media: Logo,
},
],
},
{
name: "2nd Story",
sid: "2",
appartmentDetails: [
{
aptName: "Master Bath",
status: "",
media: Logo,
},
],
},
]
);
Your add story code can remain exactly the same:
const newStory = {
name: "3rd Story",
sid: "3",
apartmentDetails: [],
};
updateStories([...stories, newStory]);
Pushing to apartmentDetails:
updateStories(draft=>{draft[index].apartmentDetails.push({aptName: 'New Apartment'})});
Updating apartmentDetails:
updateStories(draft=>{
const story = draft.find(story=>story.sid === '2');
story.apartmentDetails[0].aptName = 'Better Bath'
});
If you don't want an external library it's much more complicated to work with:
setStories(stories=>stories.map((story,index)=>index===changeIndex? {...story, apartmentDetails: story.apartmentDetails.concat([{aptName: 'New Apartment'}])} :story));
You can find a specific story using Array.find:
const story = stories.find(story => story.sid === '3');
const storyWithDetails = {...story, appartmentDetails: [{aptName: "Master Bath"}]};
To manipulate existing appartmentDetails array you can use array methods like:
const storyWithDetails = {...story, appartmentDetails: story.appartmentDetails.filter()]};
const storyWithDetails = {...story, appartmentDetails: story.appartmentDetails.map()]};
const storyWithDetails = {...story, appartmentDetails: story.appartmentDetails.slice()]}
... and so on. Then put it back into state like:
const otherStoris = stories.filter(story => story.sid !== '3');
setStory([...otherStoris, storyWithDetails]);
#Zachary Haber, i am adding changeIndex and its saying; "cant find variable changeIndex"
Related
My array contains multiple arrays and to access the objects, I have used multiple forEach. How do I handle using multiple foreach loops?
Kindly suggest an equivalent method to avoid this chaining.
See the below snippet and suggest a better solution to optimize my code.
var v = [
{
"company_name": "Apple",
"company_code": "AP",
"states": [
{
"state_name": "California",
"state_code": "CA",
"locations": [
{
"location_name": "USA - New York",
"location_code": "US - NY"
},
{
"location_name": "USA - San Francisco",
"location_code": "US - SF"
}
]
},
{
"state_name": "Rajasthan",
"state_code": "RJ",
"locations": [
{
"location_name": "Udaipur",
"location_code": "UDR"
},
{
"location_name": "Jaipur",
"location_code": "JP"
}
]
}
]
}
]
var AllData=[]
for (let i = 0; i < v.length; i++) {
const data = v[i];
//console.log(data);
data.states.forEach((state) => {
state.locations.forEach((location) => {
const ELEMENT_DATA = {
companyname: data.company_name,
statename: state.state_name,
locationname: location.location_name,
};
AllData.push(ELEMENT_DATA);
});
});
}
console.log(AllData);
Not really an optimisation, more of a readability improvement:
const arr = v.map(data =>
data.states.map(state =>
state.locations.map(location =>
({
companyname: data.company_name,
statename: state.state_name,
locationname: location.location_name
})
)
)
);
Check the following snippet to see if the output is the same.
var v = [{
"company_name": "Apple",
"company_code": "AP",
"states": [{
"state_name": "California",
"state_code": "CA",
"locations": [{
"location_name": "USA - New York",
"location_code": "US - NY"
},
{
"location_name": "USA - San Francisco",
"location_code": "US - SF"
}
]
},
{
"state_name": "Rajasthan",
"state_code": "RJ",
"locations": [{
"location_name": "Udaipur",
"location_code": "UDR"
},
{
"location_name": "Jaipur",
"location_code": "JP"
}
]
}
]
}]
const arr = v.map(data =>
data.states.map(state =>
state.locations.map(location =>
({
companyname: data.company_name,
statename: state.state_name,
locationname: location.location_name
})
)
)
);
console.log(arr)
This is basically your code, looping on each of the properties, it is just more easy to read.
{
"a": [
[
{
"_id": "57e55b64016c3551c025abc1",
"title": "Main Campus"
},
{
"_id": "5810e2e27064497f74ad4874",
"title": "Ahm Campus"
},
{
"_id": "5d5d2633a1d0680620ac3cce",
"title": "Baroda"
},
{
"_id": "5d5d3af3a1d0680620ac3ef8",
"title": "India"
}
],
[
{
"_id": "57e55b64016c3551c025abc1",
"title": "Main Campus"
},
{
"_id": "5810e2e27064497f74ad4874",
"title": "Ahm Campus"
},
{
"_id": "5d5d2633a1d0680620ac3cce",
"title": "Baroda"
},
{
"_id": "5d5d3af3a1d0680620ac3ef8",
"title": "India"
}
]
]
}
How to create the schema in the realm(React native) for this type of JSON object. I tried all possible ways but did not found any specific solution. Basically, it is a nested array where the second array does not have any specific key(I tried with key it works fine but I want to do it without adding key).
You can use something like:
const ParentSchema = {
name: "parent",
properties: {
key: "string",
values: "Value[]"
}
};
const ValueSchema = {
name: "Value",
embedded: true,
properties: {
_id: "string",
title: "string"
}
};
You can insert objects like:
realm.write(() => {
realm.create("Parent", { key: "a", values: [
{ _id: "57e55b64016c3551c025abc1", title: "Main Campus" },
{ _id: "5810e2e27064497f74ad4874", title: "Ahm Campus" }
]
});
});
Documentation: https://docs.mongodb.com/realm/node/data-model
As of now there is no way to insert direct value in Realm database without key so for now we need to modify data and then we can store in following schema.
const ParentSchema = {
name: "parent",
properties: {
a: "level[]"
}
};
const level = {
name: 'level',
properties: {
level: 'sites[]'
}
}
const sites = {
name: 'sites',
properties: {
sites: 'site[]'
}
}
const site = {
name: 'site',
properties: {
title: 'string?',
_id: 'string?',
version: 'int?',
}
}
Data modification need to done like following.
var a = {
level: []
}
data.a.map((Site, index) => {
const sites = []
Site.map((s) => { sites.push(s)})
a.level.push({sites})
})
I am making a mongodb model>>
const mongoose = require('mongoose');
const {Schema} = mongoose;
const locationSchema = new Schema({
name: String,
Address: String,
ContactInfo: {
phone: Number,
email: String,
},
Website: String,
Hours: {
DaysOpen: String,
OpeningTime:[Number],
ClosingTime:[Number],
},
Services: String,
Languages: String,
Documentation: Boolean,
OtherNotes: String,
})
mongoose.model('Locations', locationSchema);
When I try and run a get request to see what is in my database I am returned
{
"error": false,
"location": {
"Hours": {
"OpeningTime": [
1215,
898
],
"ClosingTime": [
1400
],
"DaysOpen": "Sunday"
},
"_id": "5ee8fd2e57aa5126d4c1c854",
"name": "Evergreen Christian Center Food Pantry",
"Address": "4400 NW Glencoe Rd, Hillsboro, OR 97124",
"ContactInfo": {
"phone": 5033196590,
"email": "gonzocyn2#msn.com"
},
"Website": "https://www.ecc4.org/home",
"Services": "All foods available including meat and frozen foods",
"Languages": "English, Spanish",
"Documentation": false,
"OtherNotes": "Bring own bag or box. Sign up starts at 9:00am",
"__v": 0
}
The problem is that "Hours" is being displayed before the name, address, and contact info. This only occurs when I have the fields "OpeningTime" and "ClosingTime" as arrays. Any idea on how to fix this?
I'm currently working on a new application in React. This is the first time I'm creating something in React. The application will display our own promotions.
My initial state is as follows:
{
"promotion": {
"name": "",
"campaign": "",
"url": "https://",
"position": 0,
"periods": [
{
"startDateTimeStamp": 1510558814960,
"endDateTimeStamp": 1510558814960,
"variants": [
{
"title": "",
"text": "",
"image": ""
}
]
}
]
}
}
This is created from my defaultPromotion constant. This constant is stored in a separate file, which I call api.js
export const defaultPromotion = {
name: '',
campaign: '',
url: 'https://',
position: 0,
periods: [
{
startDateTimeStamp: Date.now(),
endDateTimeStamp: Date.now(),
variants: [
{
title: '',
text: '',
image: '',
},
]
},
]
}
In my createPromotion component it's created as followed
let promotionState = api.promotions.defaultPromotion;
this.state = {
promotion: promotionState
};
I can add a new period with the following:
addPromotion() {
let promotion = this.state.promotion;
promotion.periods.push( api.promotions.defaultPromotion.periods[0] );
this.forceUpdate();
}
After that, a new period is added as expected. Suggestions to do this with setState() are very welcome! So, my new state is now:
{
"promotion": {
"name": "",
"campaign": "",
"url": "https://",
"position": 0,
"periods": [
{
"startDateTimeStamp": 1510559984421,
"endDateTimeStamp": 1510559984421,
"variants": [
{
"title": "",
"text": "",
"image": ""
}
]
},
{
"startDateTimeStamp": 1510559984421,
"endDateTimeStamp": 1510559984421,
"variants": [
{
"title": "",
"text": "",
"image": ""
}
]
}
]
}
}
Now, I want to add a new variant for this promotion period, this is where I'm stuck for 2 days now.
I'm adding a new period as follows:
addVariant( periodKey ) {
const promotion = this.state.promotion;
promotion.periods[periodKey].variants.push(api.promotions.defaultPromotion.periods[0].variants[0]);
this.setState({ promotion: promotion });
}
periodKey is here "1", so, I'm expecting that there will be added a new variant for periods[1], but, it's added to both periods. State is now as follows:
{
"promotion": {
"name": "",
"campaign": "",
"url": "https://",
"position": 0,
"periods": [
{
"startDateTimeStamp": 1510559984421,
"endDateTimeStamp": 1510559984421,
"variants": [
{
"title": "",
"text": "",
"image": ""
},
{
"title": "",
"text": "",
"image": ""
}
]
},
{
"startDateTimeStamp": 1510559984421,
"endDateTimeStamp": 1510559984421,
"variants": [
{
"title": "",
"text": "",
"image": ""
},
{
"title": "",
"text": "",
"image": ""
}
]
}
]
}
}
Can someone explain me why this is happening and how I can add a new variant the right way?
Many, many thanks in advance!
UPDATE 1
Based on the answers from bennygenel and Patrick Hübl-Neschkudla, my implementation is now as follows:
Setting the initial state:
constructor(props) {
super(props);
let promotionState = api.promotions.defaultPromotion;
this.state = { ...promotionState };
}
Method:
addVariant( periodKey ) {
this.setState((prevState) => {
const { periods } = prevState;
periods[periodKey].variants.push(
Object.assign({}, { ...periods[periodKey].variants, api.promotions.defaultPromotion.periods[0].variants[0]})
);
return { periods };
});
}
But this still is setting the new variant in all the periods. I've also tried the exact code from Benny, but with the same results. The method is called as
this.props.addVariant( this.props.periodKey );
Even when I call it as:
this.props.addVariant(2);
The same behaviour is happening.
UPDATE 2
I now have rewritten everything to redux, this is so I have access to my promotion in every component the easy way, instead off passing them through certain components. Based on the answer of #mersocarlin, I now have the following reducer cases:
Add period
case PROMOTION_ADD_PERIOD:
const { periods } = { ...state };
periods.push(api.promotions.defaultPromotion.periods[0]);
state = {
...state,
periods: periods
};
break;
Add a period variant
case PROMOTION_ADD_PERIOD_VARIANT :
state = {
...state,
periods: [
...state.periods[action.payload.period],
{
variants: [
...state.periods[action.payload.period].variants,
api.promotions.defaultPromotion.periods[0].variants[0]
]
}
]
};
break;
The following case:
Add a new variant, works, state:
{
"name": "",
"campaign": "",
"url": "https://",
"position": 0,
"periods": [
{
"startDateTimeStamp": 1510599968588,
"endDateTimeStamp": 1510599968588,
"variants": [
{
"title": "",
"text": "",
"image": ""
}
]
},
{
"startDateTimeStamp": 1510599968594,
"endDateTimeStamp": 1510599968594,
"variants": [
{
"title": "",
"text": "",
"image": ""
}
]
}
]
}
After that, adding a new variant, kinda works, well, the variant is added, but I'm losing my 2nd period. State:
{
"name": "",
"campaign": "",
"url": "https://",
"position": 0,
"periods": [
{
"variants": [
{
"title": "",
"text": "",
"image": ""
},
{
"title": "",
"text": "",
"image": ""
}
]
}
]
}
I think this is a small thing I'm not see'ing. Does someone have the solution for the "PROMOTION_ADD_PERIOD_VARIANT" case?
Update 3
Changed the "PROMOTION_ADD_PERIOD" case as follows:
case PROMOTION_ADD_PERIOD:
state = {
...state,
periods: [
...state.periods,
initialState.periods[0]
]
};
break;
Update 4
Finaly found the solution. See the final code for PROMOTION_ADD_PERIOD_VARIANT below:
state = {
...state,
periods: [
...state.periods.map((item, index) => {
if ( index !== action.payload.period ) {
return item;
}
return {
...item,
variants: [
...item.variants,
initialState.periods[0].variants[0]
]
}
})
]
};
Thank you all so much for your help!!
Rather destruct your state object and avoid mutating it directly. This also happens to be a bad pattern.
Whenever you need to add a new item to the array:
const state = {
arrayProp: [{ prop1: 'prop1', prop2: 'prop2' }]
}
const newItem = {
prop1: 'value1',
prop2: 'value2',
}
const newState = {
...state,
arrayProp: [
...state.arrayProp,
newItem,
]
}
console.log('newState', newState)
Same applies for nested properties within your state:
Redux also uses this very same approach
const state = {
objectProp: {
arrayPropWithinArray: [
{ id: '0', otherProp: 123, yetAnotherProp: 'test' },
{ id: '1', otherProp: 0, yetAnotherProp: '' }
]
}
}
const { objectProp } = state
const index = objectProp.arrayPropWithinArray.findIndex(obj => obj.id === '1')
const newSubItem = {
otherProp: 1,
yetAnotherProp: '2',
}
const newState = {
...state,
objectProp: {
...objectProp,
arrayPropWithinArray: [
...objectProp.arrayPropWithinArray.slice(0, index),
{
...objectProp.arrayPropWithinArray[index],
...newSubItem,
},
...objectProp.arrayPropWithinArray.slice(index + 1),
]
}
}
console.log('newState', newState)
Your specific case (as described in your comment)
const periodKey = '2' // your periodKey var. Get it from the right place, it can be your action for example
const index = state.periods.findIndex(period => period.id === periodKey) // find which index has to be updated
state = {
...state, // propagates current state
periods: [
...state.periods.slice(0, index), // propagates everything before index
{
...state.periods[index],
variants: [
...state.periods[index].variants,
api.promotions.defaultPromotion.periods[0].variants[0],
],
},
...state.periods.slice(0, index + 1) // propagates everything after index
]
}
So, what's happening here is that you have an array with two references to the same object.
Imagine it like this:
myArray[0] = reference to defaultPromotion
myArray[1] = reference to defaultPromotion
That's actually a wonderful example of why immutability concepts got so much attention in the past few years :)
What you'd want to do here is instead of adding the defaultPromotion object to the promotions array, you create a new object with the same props as this object and add it. It would look something like this (depending on your ES version etc.)
promotion.periods.push(
Object.assign({}, api.promotions.defaultPromotion.periods[0])
);
This way, you're creating a new object and pass this to the array instead of a reference to the already existing one.
First suggestion, if you are going to have only one promotion object in your state and not an array, lose the promotion level. this will reduce the complexity of your state. You can use spread syntax to easily set your initial state.
Example
let promotionState = api.promotions.defaultPromotion;
this.state = { ...promotionState };
Above code would end up creating a state like below;
{
"name": "",
"campaign": "",
"url": "https://",
"position": 0,
"periods": [{
"startDateTimeStamp": 1510559984421,
"endDateTimeStamp": 1510559984421,
"variants": [{
"title": "",
"text": "",
"image": ""
}]
}, {
"startDateTimeStamp": 1510559984421,
"endDateTimeStamp": 1510559984421,
"variants": [{
"title": "",
"text": "",
"image": ""
}]
}]
}
Another suggestion I can make is to use functional setState to reduce possibility to mutate.
Example
addPromotion() {
this.setState((prevState) => {
const { periods } = prevState;
periods.push(api.promotions.defaultPromotion.periods[0]);
return { periods };
});
}
addVariant( periodKey ) {
this.setState((prevState) => {
const { periods } = prevState;
periods[periodKey].variants.push(api.promotions.defaultPromotion.periods[0].variants[0]);
return { periods };
});
}
I need to modify a document inside an array that is inside another array.
I know MongoDB doesn't support multiple '$' to iterate on multiple arrays at the same time, but they introduced arrayFilters for that.
See: https://jira.mongodb.org/browse/SERVER-831
MongoDB's sample code:
db.coll.update({}, {$set: {“a.$[i].c.$[j].d”: 2}}, {arrayFilters: [{“i.b”: 0}, {“j.d”: 0}]})
Input: {a: [{b: 0, c: [{d: 0}, {d: 1}]}, {b: 1, c: [{d: 0}, {d: 1}]}]}
Output: {a: [{b: 0, c: [{d: 2}, {d: 1}]}, {b: 1, c: [{d: 0}, {d: 1}]}]}
Here's how the documents are set:
{
"_id" : ObjectId("5a05a8b7e0ce3444f8ec5bd7"),
"name" : "support",
"contactTypes" : {
"nonWorkingHours" : [],
"workingHours" : []
},
"workingDays" : [],
"people" : [
{
"enabled" : true,
"level" : "1",
"name" : "Someone",
"_id" : ObjectId("5a05a8c3e0ce3444f8ec5bd8"),
"contacts" : [
{
"_id" : ObjectId("5a05a8dee0ce3444f8ec5bda"),
"retries" : "1",
"priority" : "1",
"type" : "email",
"data" : "some.email#email.com"
}
]
}
],
"__v" : 0
}
Here's the schema:
const ContactSchema = new Schema({
data: String,
type: String,
priority: String,
retries: String
});
const PersonSchema = new Schema({
name: String,
level: String,
priority: String,
enabled: Boolean,
contacts: [ContactSchema]
});
const GroupSchema = new Schema({
name: String,
people: [PersonSchema],
workingHours: { start: String, end: String },
workingDays: [Number],
contactTypes: { workingHours: [String], nonWorkingHours: [String] }
});
I need to update a contact. This is what I tried using arrayFilters:
Group.update(
{},
{'$set': {'people.$[i].contacts.$[j].data': 'new data'}},
{arrayFilters: [
{'i._id': mongoose.Types.ObjectId(req.params.personId)},
{'j._id': mongoose.Types.ObjectId(req.params.contactId)}]},
function(err, doc) {
if (err) {
res.status(500).send(err);
}
res.send(doc);
}
);
The document is never updated and I get this response:
{
"ok": 0,
"n": 0,
"nModified": 0
}
What am I doing wrong?
So the arrayFilters option with positional filtered $[<identifier>] does actually work properly with the development release series since MongoDB 3.5.12 and also in the current release candidates for the MongoDB 3.6 series, where this will actually be officially released. The only problem is of course is that the "drivers" in use have not actually caught up to this yet.
Re-iterating the same content I have already placed on Updating a Nested Array with MongoDB:
NOTE Somewhat ironically, since this is specified in the "options" argument for .update() and like methods, the syntax is generally compatible with all recent release driver versions.
However this is not true of the mongo shell, since the way the method is implemented there ( "ironically for backward compatibility" ) the arrayFilters argument is not recognized and removed by an internal method that parses the options in order to deliver "backward compatibility" with prior MongoDB server versions and a "legacy" .update() API call syntax.
So if you want to use the command in the mongo shell or other "shell based" products ( notably Robo 3T ) you need a latest version from either the development branch or production release as of 3.6 or greater.
All this means is that the current "driver" implementation of .update() actually "removes" the necessary arguments with the definition of arrayFilters. For NodeJS this will be addressed in the 3.x release series of the driver, and of course "mongoose" will then likely take some time after that release to implement it's own dependencies on the updated driver, which would then no longer "strip" such actions.
You can however still run this on a supported server instance, by dropping back to the basic "update command" syntax usage, since this bypassed the implemented driver method:
const mongoose = require('mongoose'),
Schema = mongoose.Schema,
ObjectId = mongoose.Types.ObjectId;
mongoose.Promise = global.Promise;
mongoose.set('debug',true);
const uri = 'mongodb://localhost/test',
options = { useMongoClient: true };
const contactSchema = new Schema({
data: String,
type: String,
priority: String,
retries: String
});
const personSchema = new Schema({
name: String,
level: String,
priority: String,
enabled: Boolean,
contacts: [contactSchema]
});
const groupSchema = new Schema({
name: String,
people: [personSchema],
workingHours: { start: String, end: String },
workingDays: { type: [Number], default: undefined },
contactTypes: {
workingHours: { type: [String], default: undefined },
contactTypes: { type: [String], default: undefined }
}
});
const Group = mongoose.model('Group', groupSchema);
function log(data) {
console.log(JSON.stringify(data, undefined, 2))
}
(async function() {
try {
const conn = await mongoose.connect(uri,options);
// Clean data
await Promise.all(
Object.entries(conn.models).map(([k,m]) => m.remove() )
);
// Create sample
await Group.create({
name: "support",
people: [
{
"_id": ObjectId("5a05a8c3e0ce3444f8ec5bd8"),
"enabled": true,
"level": "1",
"name": "Someone",
"contacts": [
{
"type": "email",
"data": "adifferent.email#example.com"
},
{
"_id": ObjectId("5a05a8dee0ce3444f8ec5bda"),
"retries": "1",
"priority": "1",
"type": "email",
"data": "some.email#example.com"
}
]
}
]
});
let result = await conn.db.command({
"update": Group.collection.name,
"updates": [
{
"q": {},
"u": { "$set": { "people.$[i].contacts.$[j].data": "new data" } },
"multi": true,
"arrayFilters": [
{ "i._id": ObjectId("5a05a8c3e0ce3444f8ec5bd8") },
{ "j._id": ObjectId("5a05a8dee0ce3444f8ec5bda") }
]
}
]
});
log(result);
let group = await Group.findOne();
log(group);
} catch(e) {
console.error(e);
} finally {
mongoose.disconnect();
}
})()
Since that sends the "command" directly through to the server, we see the expected update does in fact take place:
Mongoose: groups.remove({}, {})
Mongoose: groups.insert({ name: 'support', _id: ObjectId("5a06557fb568aa0ad793c5e4"), people: [ { _id: ObjectId("5a05a8c3e0ce3444f8ec5bd8"), enabled: true, level: '1', name: 'Someone', contacts: [ { type: 'email', data: 'adifferent.email#example.com', _id: ObjectId("5a06557fb568aa0ad793c5e5") }, { _id: ObjectId("5a05a8dee0ce3444f8ec5bda"), retries: '1', priority: '1', type: 'email', data: 'some.email#example.com' } ] } ], __v: 0 })
{ n: 1,
nModified: 1,
opTime:
{ ts: Timestamp { _bsontype: 'Timestamp', low_: 3, high_: 1510364543 },
t: 24 },
electionId: 7fffffff0000000000000018,
ok: 1,
operationTime: Timestamp { _bsontype: 'Timestamp', low_: 3, high_: 1510364543 },
'$clusterTime':
{ clusterTime: Timestamp { _bsontype: 'Timestamp', low_: 3, high_: 1510364543 },
signature: { hash: [Object], keyId: 0 } } }
Mongoose: groups.findOne({}, { fields: {} })
{
"_id": "5a06557fb568aa0ad793c5e4",
"name": "support",
"__v": 0,
"people": [
{
"_id": "5a05a8c3e0ce3444f8ec5bd8",
"enabled": true,
"level": "1",
"name": "Someone",
"contacts": [
{
"type": "email",
"data": "adifferent.email#example.com",
"_id": "5a06557fb568aa0ad793c5e5"
},
{
"_id": "5a05a8dee0ce3444f8ec5bda",
"retries": "1",
"priority": "1",
"type": "email",
"data": "new data" // <-- updated here
}
]
}
]
}
So right "now"[1] the drivers available "off the shelf" don't actually implement .update() or it's other implementing counterparts in a way that is compatible with actually passing through the necessary arrayFilters argument. So if you are "playing with" a development series or release candiate server, then you really should be prepared to be working with the "bleeding edge" and unreleased drivers as well.
But you can actually do this as demonstrated in any driver, in the correct form where the command being issued is not going to be altered.
[1] As of writing on November 11th 2017 there is no "official" release of MongoDB or the supported drivers that actually implement this. Production usage should be based on official releases of the server and supported drivers only.
I had a similar use case. But my second level nested array doesn't have a key. While most examples out there showcase an example with arrays having a key like this:
{
"id": 1,
"items": [
{
"name": "Product 1",
"colors": ["yellow", "blue", "black"]
}
]
}
My use case is like this, without the key:
{
"colors": [
["yellow"],
["blue"],
["black"]
]
}
I managed to use the arrayfilters by ommiting the label of the first level of the array nest. Example document:
db.createCollection('ProductFlow')
db.ProductFlow.insertOne(
{
"steps": [
[
{
"actionType": "dispatch",
"payload": {
"vehicle": {
"name": "Livestock Truck",
"type": "road",
"thirdParty": true
}
}
},
{
"actionType": "dispatch",
"payload": {
"vehicle": {
"name": "Airplane",
"type": "air",
"thirdParty": true
}
}
}
],
[
{
"actionType": "store",
"payload": {
"company": "Company A",
"is_supplier": false
}
}
],
[
{
"actionType": "sell",
"payload": {
"reseller": "Company B",
"is_supplier": false
}
}
]
]
}
)
In my case, I want to:
Find all documents that have any steps with payload.vehicle.thirdParty=true and actionType=dispatch
Update the actions set payload.vehicle.thirdParty=true only for the actions that have actionType=dispatch.
My first approach was withour arrayfilters. But it would create the property payload.vehicle.thirdParty=true inside the steps with actionType store and sell.
The final query that updated the properties only inside the steps with actionType=dispatch:
Mongo Shell:
db.ProductFlow.updateMany(
{"steps": {"$elemMatch": {"$elemMatch": {"payload.vehicle.thirdParty": true, "actionType": "dispatch"}}}},
{"$set": {"steps.$[].$[i].payload.vehicle.thirdParty": false}},
{"arrayFilters": [ { "i.actionType": "dispatch" } ], multi: true}
)
PyMongo:
query = {
"steps": {"$elemMatch": {"$elemMatch": {"payload.vehicle.thirdParty": True, "actionType": "dispatch"}}}
}
update_statement = {
"$set": {
"steps.$[].$[i].payload.vehicle.thirdParty": False
}
}
array_filters = [
{ "i.actionType": "dispatch" }
]
NOTE that I'm omitting the label on the first array at the update statement steps.$[].$[i].payload.vehicle.thirdParty. Most examples out there will use both labels because their objects have a key for the array. I took me some time to figure that out.