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Javascript adding an object inside an existing object

I want the user to have the option to add more stepTypes, stepCodes and properties. He can add an stepCode with an existing StepType, or with a different stepType, so, the object would like similar to this:
You see? In the stepType called 'guide', I have 2 stepCodes (G019, G040). In the stepType called 'success', I have just one (S003), and so on. Since I'm newbie with js and even more with objects, I'd like you guys to help me creating a function that checks if the stepType already exists, and then adds another stepCode to it (with its properties). And, if it doesn't exist yet, I want this function to create this new stepType, with the stepCode and its properties.
Currently, my code looks like this:
const checkStep = () => {
if (!Object.keys(procedures).length) {
let proc =
{[key]:
{
[stepType]: {
[stepCode]: {
[language]: stepText,
timeout,
nextInstruction,
}
}
}
}
setProcedures(proc)
}
else{
Object.entries(procedures).forEach((p, k) =>{
...
})
}
}
I call this function everytime the user clicks the "Add another step" button. The first part checks if the object already exists, and, if it doesn't, it creates the object with its key and so on (this part is working). What I don't know how to do is the ELSE part. I think we have to check if the stepType already exists in the object called procedures, but I don't know how to do it. I don't know how to put the stepCode and properties inside the existing object(procedures) either. Maybe I create a variable and do like: setProcedures (...procedures, variable). I don't want to lose the content I have in the procedure, just to add more content to it in the way I explained you.
P.S.: All the variables (stepType, stepCode, language, stepText, timeout, nextInstruction) are an useState. When the user writes anything in the input text field, I set the specific variable with the e.target.value.
Thank you.

You can do the loop on the each keys and if it matches then add to existing data or create a new stepType and add.
var newStepType = "test", stepCode="test1", language ="en", stepText="hello", timeout=9, nextInstruction="new ins";
Object.keys(procedure.DOF0014).forEach(key => {
//if newStepType matches insert stepCode. eg: stepType is "guide"
if(key === newStepType) {
procedure.DOF0014[key] = { ...procedure.DOF0014[key], ...{[stepCode]: {[language]: stepText,timeout,nextInstruction}}}
}else{
procedure.DOF0014 = {...procedure.DOF0014, ...{[newStepType]:{[stepCode]: {[language]: stepText,timeout,nextInstruction}}}};
}
});
Try this. I didnt tested code. But hope it works. I am sharing the idea how to do.
Object.keys(procedure).forEach(codes => {
Object.keys(procedure[codes]).forEach(key => {
if(key === newStepType) {
procedure[codes][key] = { ...procedure[codes][key], ...{[stepCode]: {[language]: stepText,timeout,nextInstruction}}}
}else{
procedure[codes] = {...procedure[codes], ...{[newStepType]:{[stepCode]: {[language]: stepText,timeout,nextInstruction}}}};
}
});
})

How to pass by value and not by reference in React?

I have the following file, LookupPage.jsx and AccountDetails.jsx.
In LookUp
this.updateCustomer = (customer) => {
if(JSON.stringify(customer.address) !== JSON.stringify(this.state.activeAccount.customer.address)) {
console.log('address changed');
customer.update_address = true;
customer.address.source = 'user';
}
return fetch(
`${API_ENDPOINT}/customer/${customer.id}/`,
{
method: 'PATCH',
headers: {
'Authorization': 'Token ' + this.props.session_token,
'Content-Type': 'application/json',
},
body: JSON.stringify(customer),
}
).then(restJSONResponseToPromise).then(responseJSON => {
if(responseJSON.results){
console.log('update customers client side.')
}
}, clearSessionIfInvalidToken(this.props.clearSession));
};
<AccountsDetailModal
show={this.state.showAccountDetail}
close={this.toggleAccountDetail}
customer={this.state.activeAccount.customer}
updateCustomer={this.updateCustomer}
/>
In side AccountDetails
this.onChangeAddress = (e) => {
const customer = {...this.state.customer};
const address = customer.address;
address[e.target.name] = e.target.value;
customer.address = address;
this.setState({customer, errors: {
...this.state.errors,
[e.target.name]: [],
}});
};
this.saveCustomer = () => {
this.setState({postDisable: true});
const errors = this.getFormErrors();
const hasErrors = !every(errors, (item) => !item.length);
if(!hasErrors){
this.props.updateCustomer(this.state.customer);
} else {
sweetAlert('Error!', 'Form is invalid.', 'error');
}
this.setState({postDisable: false});
};
this.componentDidMount = () => {
this.setState({customer: this.props.customer});
}
When I am updating the customers address, it is updating active accounts address, so it seems like it is being passed by reference. What I want to happen is only update the customer address if the address was changed/different from the original. How would I modify my code to do this?

You can pass any object by value in JS (whether you're using React or not) by passing:
JSON.parse(JSON.stringify(myObject))
as an argument instead of the object itself.
Essentially this will just clone the object and pass a copy of it, so you can manipulate the copy all you want without affecting the original.
Note that this will not work if the object contains functions, it will only copy the properties. (In your example this should be fine.)

I am going to put my two cents here:
First of all, this isn't really specific to React and is more of a JS related question.
Secondly, setting props against internal state is considered to be a bad practice when it comes to react. There's really no need to do that given your particular scenario. I am referring to
this.setState({customer: this.props.customer});
So, coming to your problem, the reason you are having reference issues is because you are mutating the original passed in object at certain points in your code. For instance, if I look at:
this.updateCustomer = (customer) => {
if(JSON.stringify(customer.address) !== JSON.stringify(this.state.activeAccount.customer.address)) {
console.log('address changed');
customer.update_address = true;
customer.address.source = 'user';
}
};
You are mutating the original props of the argument object which is very likely to be passed around in other methods of your component. So, to overcome that you can do:
const updatedCustomer = Object.assign({}, customer, {
update_address: true
});
And you can pass in updatedCustomer in your API call. Object.assign() will not perform operation on the passed in object but will return a new object so you can be sure that at any point in your app you are not mutating the original object.
Note: Object.assign would work on plain object and not a nested one. So, if you want to achieve something similar that would work on nested object properties too, you can use lodash merge.

changing prototype Elements set scopes

I am wanting to attach into an Elements default property such as innerHTML as a backup under an object that way it does not pollute the Elements properties. so to help give an idea of what I am trying to achieve and what currently works:
Element.prototype._backupPropertyDescriptors = {};
Element.prototype._backupProperties = {};
Element.prototype._backupPropertyDescriptors._innerHTML = Object.getOwnPropertyDescriptor(Element.prototype,'innerHTML');
//This is what I want to do but loses Elements scope:
Object.defineProperty(Element.prototype._backupProperties,'_innerHTML',Element.prototype._backupPropertyDescriptors._innerHTML);
//the scope has changed from element to _backupProperties so this property fails.
//The working version:
Object.defineProperty(Element.prototype,'_innerHTML',Element.prototype._backupPropertyDescriptors._innerHTML);
//the reason for this is I want to be able to manipulate the get and set such as:
Object.defineProperty(Element.prototype._backupProperties,'_innerHTML',{configurable:true,enumerable:true,get:function(){console.log('getting',this.innerHTML);return this.innerHTML},set:function(val){console.log('doing something here before setting');this.innerHTML = val;}});
The problem with this is once it is inside of backup the this statement no longer holds the element...
I know one way to do this would be to use a bind or call but that still poses the how do I get the elements scope... as this during define property is the window..

So for anyone looking to try and do this, here is the solution I found :) might be something better out there, but this does work. requires only 3 properties in the prototype and then all others get put inside a single one.
Element.prototype._backupPropertyDescriptors = {};
Element.prototype._backupProperties = {};
Object.defineProperty(Element.prototype,'_backupProvider',
{
writeable:false,
enumerable:true,
configurable:true,
get:function()
{
var _backupProperties = this._backupProperties;
_backupProperties._Element = this;
return {_Element:this,_backupPropertyDescriptors:this._backupPropertyDescriptors,_backupProperties:_backupProperties};
}
});
//These first ones set up the main provider and property and descriptor holders.
//then just copy a descriptor:
Element.prototype._backupPropertyDescriptors._innerHTML = Object.getOwnPropertyDescriptor(Element.prototype,'innerHTML');
//and assign it to a new property inside the backupProperties:
Object.defineProperty(Element.prototype._backupProvider._backupProperties,'_innerHTML',
{
enumerable:true,
configurable:true,
get:function()
{
return this._Element._backupProvider._backupPropertyDescriptors._innerHTML.get.call(this._Element);
},
set:function(val)
{
console.log('setting html to: ',val);
this._Element._backupProvider._backupPropertyDescriptors._innerHTML.set.call(this._Element,val);
}
});
//and if you wanted to do something really crazy.... like overwrite the original..
Object.defineProperty(Element.prototype,'innerHTML',
{
enumerable:true,
configurable:true,
get:function()
{
return this._backupProvider._backupProperties._innerHTML;
},
set:function(val)
{
console.log('setting html to: ',val);
//do some crazy two way template binding here or something else crazy
this._backupProvider._backupProperties._innerHTML = val;
}
});
that is all.. thanks for the help #Bergi

Meteor Storing and Retrieving Custom Objects in Session

I have a custom shopping cart object that I created and put it in the lib folder.
ShoppingCart = function ShoppingCart() {
this.Items = new Array();
this.grandTotal = 0.00;
}
ShoppingCart.prototype.addItem = function(Item){
this.Items.push(Item);
this.Items.sort();
this.calculateTotal();
}
I initialized the shopping cart and store it as Session.set('shoppingCart') during the page created phase.
Template.loginStatus.created = function() {
Session.set('loginShown',false);
if(!Session.get('shoppingCart')){ //set default if session shopping cart not exist
var cart = new ShoppingCart();
Session.setDefault('shoppingCart',cart);
}
Then when user click add item to cart, it will trigger this logic:
var cart = Session.get('shoppingCart');
cart.addItem(item);
Session.set('shoppingCart',cart);
Somehow, it does not work. When I take a look ad the chrome console it says undefined is not a function, pointing at cart.addItem(item) line. If I change it to this, it will work , but of course since everytime new shopping cart is created, I cannot accumulate items in the cart.
var cart = new ShoppingCart();
cart.addItem(item);
Session.set('shoppingCart',cart);
How should I store and retrieve the object from session properly? It looks like the returned object from the Session.get() somehow not considered as ShoppingCart. Did I miss any type cast?

As #Peppe L-G mentioned, you can only store EJSONs in Session. To store your custom object, you need to be able to manually transform it to and from EJSONs. Example:
_.extend(ShoppingCart, {
fromJSON: function(json) {
var obj = new ShoppingCart();
obj.grandTotal = json.grandTotal;
obj.Items = json.Items;
return obj;
},
});
_.extend(ShoppingCart.prototype, {
toJSON: function() {
return {
grandTotal: this.grandTotal,
Items: this.Items,
};
},
});
Then you can save it to Session:
Session.set('shoppingCart', cart.toJSON());
and restore:
ShoppingCart.fromJSON(Session.get('shoppingCart'));

I ran into the same problem. Essentially what is happening Meteor Sessions (and Collections) can only store EJSON types, so your ShoppingCart custom type is retrieved from the Session as a normal Object.
While you can manually transform to and from EJSONs, you may end up needing to do this repeatedly in a lot of different places. If your ShoppingCart is a member of another object, you'll have to also manually transform the member. It's better to use EJSON.addType to tell Meteor how to handle it automatically anywhere you store or retrieve an object of that type.
There's a great demo of this here: https://www.eventedmind.com/feed/meteor-create-a-custom-ejson-type. Full docs are also here: http://docs.meteor.com/#/full/ejson. But a short version is this:
Add a method to your custom type called typeName:
ShoppingCart.prototoype.typeName = function(){
return "ShoppingCart";
};
Add another method called toJSONValue:
ShoppingCart.prototype.toJSONValue = function(){
/* return a JSON compatible version of your object */
};
And finally, add the custom type to EJSON with:
EJSON.addType("ShoppingCart", function fromJSONValue(value){
/* return an object of your custom type from the JSON object 'value' */
};
NOTE: the "Type Name" in steps 1 and 3 must match exactly.

Ember not updating template when I add or remove an object from an array field in the model

So I've got a model that has a field of an array objects it looks like this
App.Post = DS.Model.extend({
...
codes: attr(),
...
});
and Codes looks like this
codes: [
{
code: stuff
comment: stuff_1
other_things: other_stuff
},
{
...
},
{
...
}
...
]
So now I have an add / remove button which has actions attached to them and this is what they do
add_code_input: function() {
var codes = this.get('model.codes');
var self = this;
var last_code = codes[codes.length-1];
// Cannot edit as an ember.set error is occurring
last_code.code = 'Add new (please change)';
last_code.code_type = "";
last_code.comment = "";
console.log(last_code);
codes.push(last_code);
this.set('model.codes', codes);
console.log(codes);
},
remove_code_input: function() {
var codes = this.get('model.codes');
codes.pop();
console.log(codes);
this.set('model.codes', codes);
}
So the remove works fine but the add doesn't work.
It gives me this error when I try to update last_code: Uncaught Error: Assertion Failed: You must use Ember.set() to access this property (of [object Object])
I essentially want to add a dummy object that user can change.
So first issue is figuring out how to add dummy objects into the array properly and secondly how to update the template as the model changes.

You should be using arr.pushObject(obj) and arr.popObject() for manipulating an array in Ember (think of it as the setter/getter of arrays).
is codes really just attr() because it appears to be behaving like a DS record.
If it is a record, you just use record.set('foo', 'bar') if it's just a POJO you can use Ember.set(obj, 'foo', 'bar').
It should be as easy as this (I'm assuming you're using and in the ObjectController here)
var newCode = {
code:'foo'
};
this.get('codes').pushObject(newCode);