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lodash filter using forEach?

Having trouble filtering out some data from a deeply nested array of objects.
I need to loop through each day, then loop through each event and filter out all events that don't include an attendee with the email 'barry#gmail.com'.
'18 Sun': [
{
name: 'Event 01',
attendees: [
{
name: 'John',
email: 'john#gmail.com'
},
{
name: 'Barry',
email: 'barry#gmail.com'
}
]
}
],
'19 Mon':[
{
name: 'Event 02',
attendees: [
{
name: 'John',
email: 'john#gmail.com'
}
]
},
{
name: 'Event 03',
attendees: [
{
name: 'John',
email: 'john#gmail.com'
},
{
name: 'Barry',
email: 'barry#gmail.com'
}
]
}
]
expectation after filtering (removed Event 02 since barry#gmail.com does not exist)
'18 Sun': [
{
name: 'Event 01',
attendees: [
{
name: 'John',
email: 'john#gmail.com'
},
{
name: 'Barry',
email: 'barry#gmail.com'
}
]
}
],
'19 Mon':[
{
name: 'Event 03',
attendees: [
{
name: 'John',
email: 'john#gmail.com'
},
{
name: 'Barry',
email: 'barry#gmail.com'
}
]
}
]
I've tried this snippet
_.forEach(globalEvents, d => {
_.forEach(d, e => {
_.filter(e.attendees, p => {
return p.email === 'barry#gmail.com'
})
})
})
but this just returns the entire, unfiltered array. I would like to use lodash, but isn't necessary.

Try this code it's works..
_.forEach(data, d => {
_.remove(d, e => {
return _.some(e.attendees, {email: 'barry#gmail.com'}) != true;
})
});

How to create a nested array of object from an array of objects

How Can I loop through this array of objects and change it so that the individual menu items are nested in the object menu_name?
const menus = [
{ menu_name: 'Entre', id:0 },
{
name: 'Soup',
price: 14.99,
id:1
},
{
name: 'Chips & Salsa',
price: 7.99,
id:2
},
{
name: 'Chicken Nuggets',
price: 12.99,
id:3
},
{ menu_name: 'Sides', id:4 },
{
name: 'Fries',
price: 4.99,
id:5
},
{
name: 'Drinks',
price: 2.99,
id:6
},
{
name: 'Onion Rings',
price: 5.99,
id:7
},
];
the end result should look like this for each menu_name object, where an array of menus is nested in the menu_name object
{
menu_name: 'Sides',
menu: [
{
name: 'Fries',
price: 4.99,
},
{
name: 'Drinks',
price: 2.99,
},
{
name: 'Onion Rings',
price: 5.99,
},
],
},

You can easily achieve this using reduce and object destructuring
const menus = [
{ menu_name: "Entre", id: 0 },
{
name: "Soup",
price: 14.99,
id: 1,
},
{
name: "Chips & Salsa",
price: 7.99,
id: 2,
},
{
name: "Chicken Nuggets",
price: 12.99,
id: 3,
},
{ menu_name: "Sides", id: 4 },
{
name: "Fries",
price: 4.99,
id: 5,
},
{
name: "Drinks",
price: 2.99,
id: 6,
},
{
name: "Onion Rings",
price: 5.99,
id: 7,
},
];
const result = menus.reduce((acc, curr) => {
const { menu_name } = curr;
if (menu_name) {
acc.push({ menu_name, menu: [] });
} else {
const { name, price } = curr;
acc[acc.length - 1].menu.push({ name, price });
}
return acc;
}, []);
console.log(result);

var newMenu = [];
menus.forEach(menu=>{
if(menu.menu_name){
newMenu.push({...menu, menu: []})
}else{
newMenu[newMenu.length-1].menu.push(menu)
}
});

Grouping and summing array objects

I'm having a data sample like this
this.userData = [
{id:1, category: 'Food', amount: 30, pDate: '2021-01-13', description: 'test desc'},
{id:2, category: 'Fuel', amount: 10, pDate: '2021-01-12', description: 'test desc'},
{id:3, category: 'Food', amount: 70, pDate: '2021-01-14', description: 'test desc'},
]
What I want to achieve with this data is to group it and sum it up so it comes out like this
[
{name: Food, total: 100},
{name: Fuel, total: 30}
]
What the current code I have, I do not get the output as I want.
const data = this.userData;
const groups = data.reduce((groups, item) => ({
...groups,
[item.category]: [...(groups[item.category] || []), item]
}), {});
console.log(groups);

You could take an object for grouping and get the values.
const
userData = [{ id:1, category: 'Food', amount: 30, pDate: '2021-01-13', description: 'test desc' }, { id:2, category: 'Fuel', amount: 10, pDate: '2021-01-12', description: 'test desc' }, { id:3, category: 'Food', amount: 70, pDate: '2021-01-14', description: 'test desc' }],
groups = Object.values(userData.reduce((r, o) => {
(r[o.category] ??= { name: o.category, total: 0 }).total += o.amount;
return r;
}, {}))
console.log(groups);

Try this
const userData = [
{id:1, category: 'Food', amount: 30, pDate: '2021-01-13', description: 'test desc'},
{id:2, category: 'Fuel', amount: 10, pDate: '2021-01-12', description: 'test desc'},
{id:3, category: 'Food', amount: 70, pDate: '2021-01-14', description: 'test desc'},
]
const hashMap = {}
for (const { category, amount } of userData) {
if (hashMap[category]) {
hashMap[category].total += amount
} else {
hashMap[category] = { name: category, total: amount }
}
}
const output = Object.values(hashMap)
console.log(output)

Filter array of objects by nested array of object value

Suppose I have an array of objects, each of which contains a nested array of objects likes:
[
{
id: 1,
title: 'Lorem',
private: false,
likes: [
{ id: 01, username: 'mike' },
{ id: 02, username: 'john' }
]
},
{
id: 2,
title: 'Ipsum',
private: true,
likes: [
{ id: 03, username: 'steve' },
{ id: 04, username: 'mike' },
{ id: 05, username: 'sara' }
]
},
{
id: 3,
title: 'Dolor',
private: false,
likes: [
{ id: 06, username: 'brad' },
{ id: 07, username: 'cameron' },
{ id: 08, username: 'liam' }
]
}
]
How can I filter the outer array by the username value inside its items nested array? Let's say output the items that contains in its inner arrays objects with property username: 'mike'?

You could filter by looking into the nested array.
var data = [{ id: 1, title: 'Lorem', private: false, likes: [{ id: 01, username: 'mike' }, { id: 02, username: 'john' }] }, { id: 2, title: 'Ipsum', private: true, likes: [{ id: 03, username: 'steve' }, { id: 04, username: 'mike' }, { id: 05, username: 'sara' }] }, { id: 3, title: 'Dolor', private: false, likes: [{ id: 06, username: 'brad' }, { id: 07, username: 'cameron' }, { id: 08, username: 'liam' }] }],
result = data.filter(({ likes }) => likes.some(({ username }) => username === 'mike'));
console.log(result);
.as-console-wrapper { max-height: 100% !important; top: 0; }

Use filter and some functions:
const input = [{
id: 1,
title: "Lorem",
private: false,
likes: [{
id: 1,
username: "mike"
}, {
id: 2,
username: "john"
}]
},
{
id: 2,
title: "Ipsum",
private: true,
likes: [{
id: 3,
username: "steve"
},
{
id: 4,
username: "mike"
},
{
id: 5,
username: "sara"
}
]
},
{
id: 3,
title: "Dolor",
private: false,
likes: [{
id: 6,
username: "brad"
},
{
id: 7,
username: "cameron"
},
{
id: 8,
username: "liam"
}
]
}
];
const criteria = {
username: "mike"
};
const result = input.filter(x =>
x.likes.some(y => y.username === criteria.username)
);
console.log(result);

you can use 'map' function to filter the internal array
const data = [
{
id: 1,
title: 'Lorem',
private: false,
likes: [
{ id: 1, username: 'mike' },
{ id: 2, username: 'john' }
]
},
{
id: 2,
title: 'Ipsum',
private: true,
likes: [
{ id: 3, username: 'steve' },
{ id: 4, username: 'mike' },
{ id: 5, username: 'sara' }
]
},
{
id: 3,
title: 'Dolor',
private: false,
likes: [
{ id: 6, username: 'brad' },
{ id: 7, username: 'cameron' },
{ id: 8, username: 'liam' }
]
}
]
const res = data.map( item => {
let likes = item.likes.filter( user => user.username === 'mike')
if(likes.length > 0 ) {
item.likes = likes
return item
}
return null
}).filter(item => item !== null )
console.log(res)

use filter and find in likes.
const filter = (data, name) =>
data.filter(({ likes }) => likes.find(({ username }) => username === name));
const data = [
{
id: 1,
title: "Lorem",
private: false,
likes: [
{ id: 01, username: "mike" },
{ id: 02, username: "john" },
],
},
{
id: 2,
title: "Ipsum",
private: true,
likes: [
{ id: 03, username: "steve" },
{ id: 04, username: "mike" },
{ id: 05, username: "sara" },
],
},
{
id: 3,
title: "Dolor",
private: false,
likes: [
{ id: 06, username: "brad" },
{ id: 07, username: "cameron" },
{ id: 08, username: "liam" },
],
},
];
console.log(filter(data, "mike"));
console.log(filter(data, "blah"));

JavaScript - Flatten Array of Nested Objects

I am working with an array of objects and need to flatten and re-assign the data set into an array of single objects using the object values as the new object keys.
Incoming Data:
results = [
{
surveyValues: [
{ id: 135, name: 'First Name', value: 'Jim' },
{ id: 136, name: 'Last Name', value: 'Jones' },
{ id: 137, name: 'City', value: 'Fredsburg' },
],
},
{
surveyValues: [
{ id: 135, name: 'First Name', value: 'Greg' },
{ id: 136, name: 'Last Name', value: 'Jones' },
{ id: 137, name: 'City', value: 'Waverly' },
],
},
];
Desired Result:
output = [
{
id: 1, FirstName: 'Jim', LastName: 'Jones', City: 'Fredsburg',
},
{
id: 2, FirstName: 'Greg', LastName: 'Jones', City: 'Waverly',
},
];
My current attempt gets me to placing the updated key/value pairs in the correct order, but creates a huge array of single objects.
Current Code:
const results = [];
surveyResults.map(s => s.surveyValues)
.forEach(s => Object.entries(s)
.forEach(([key, value]) => {
Object.entries(value)
.forEach(([k, v]) => {
if (k === 'name') {
results.push({
id: value.id,
[v]: value.value.toString(),
});
}
});
}));
Current Code Output:
[
{
id: 135, FirstName: 'Jim',
},
{
id: 136, LastName: 'Jones',
},
{
id: 137, City: 'Fredsburg',
},
{
id: 135, FirstName: 'Greg',
},
{
id: 136, LastName: 'Jones',
},
{
id: 137, City: 'Waverly',
},
]
What am I missing and why is my code not created the new arrays of objects as desired?

You may use map and reduce to accomplish this. I'm also accessing an index i in the map function's callback to set the id property and string.replace() to strip the space from the FirstName and LastName keys.
const results = [
{
surveyValues: [
{ id: 135, name: 'First Name', value: 'Jim' },
{ id: 136, name: 'Last Name', value: 'Jones' },
{ id: 137, name: 'City', value: 'Fredsburg' },
],
},
{
surveyValues: [
{ id: 135, name: 'First Name', value: 'Greg' },
{ id: 136, name: 'Last Name', value: 'Jones' },
{ id: 137, name: 'City', value: 'Waverly' },
],
},
];
const result = results.map((e, i) =>
e.surveyValues.reduce((a, e) => {
a[e.name.replace(" ", "")] = e.value;
return a;
}, {id: i + 1})
);
console.log(result);

Create each object in the outer map() loop, and add properties to it in the inner forEach().
surveyResults = [
{
surveyValues: [
{ id: 135, name: 'First Name', value: 'Jim' },
{ id: 136, name: 'Last Name', value: 'Jones' },
{ id: 137, name: 'City', value: 'Fredsburg' },
],
},
{
surveyValues: [
{ id: 135, name: 'First Name', value: 'Greg' },
{ id: 136, name: 'Last Name', value: 'Jones' },
{ id: 137, name: 'City', value: 'Waverly' },
],
},
];
const results = surveyResults.map((s, i) => {
let v = s.surveyValues;
let obj = {id: i};
v.forEach(item => obj[item.name.replace(/\s+/g, "")] = item.value.toString());
return obj;
});
console.log(results);