I am currently following a tutorial that covers Lodash and it is prompting me to return this value :
{
author: "Robert C. Martin",
blogs: 3
}
given this array of objects:
const blogs = [
{
_id: "5a422a851b54a676234d17f7",
title: "React patterns",
author: "Michael Chan",
url: "https://reactpatterns.com/",
likes: 7,
__v: 0
},
{
_id: "5a422aa71b54a676234d17f8",
title: "Go To Statement Considered Harmful",
author: "Edsger W. Dijkstra",
url: "http://www.u.arizona.edu/~rubinson/copyright_violations/Go_To_Considered_Harmful.html",
likes: 5,
__v: 0
},
{
_id: "5a422b3a1b54a676234d17f9",
title: "Canonical string reduction",
author: "Edsger W. Dijkstra",
url: "http://www.cs.utexas.edu/~EWD/transcriptions/EWD08xx/EWD808.html",
likes: 12,
__v: 0
},
{
_id: "5a422b891b54a676234d17fa",
title: "First class tests",
author: "Robert C. Martin",
url: "http://blog.cleancoder.com/uncle-bob/2017/05/05/TestDefinitions.htmll",
likes: 10,
__v: 0
},
{
_id: "5a422ba71b54a676234d17fb",
title: "TDD harms architecture",
author: "Robert C. Martin",
url: "http://blog.cleancoder.com/uncle-bob/2017/03/03/TDD-Harms-Architecture.html",
likes: 0,
__v: 0
},
{
_id: "5a422bc61b54a676234d17fc",
title: "Type wars",
author: "Robert C. Martin",
url: "http://blog.cleancoder.com/uncle-bob/2016/05/01/TypeWars.html",
likes: 2,
__v: 0
}
]
I have tried a copious amount of ways to figure this out but i cannot seem to recreate the answer they want using only Lodash. Here is the code I tried but, to no avail, was I able to reproduce their answer:
const mostBlogs = async (blogs) => {
let result = _.countBy(blogs.map(blog => ({author: blog.author.value})))
const b = _.maxBy(result, 'blogs');
console.log(result);
I think you are pretty close. Something like this could work. Switched the map and countBy. First did the counting and then mapped over the result object
const blogs = [{_id: "5a422a851b54a676234d17f7",title: "React patterns",author: "Michael Chan",url: "https://reactpatterns.com/",likes: 7,__v: 0}, { _id: "5a422aa71b54a676234d17f8", title: "Go To Statement Considered Harmful", author: "Edsger W. Dijkstra",url: "http://www.u.arizona.edu/~rubinson/copyright_violations/Go_To_Considered_Harmful.html",likes: 5,__v: 0}, {_id: "5a422b3a1b54a676234d17f9", title: "Canonical string reduction", author: "Edsger W. Dijkstra", url: "http://www.cs.utexas.edu/~EWD/transcriptions/EWD08xx/EWD808.html", likes: 12, __v: 0}, { _id: "5a422b891b54a676234d17fa", title: "First class tests", author: "Robert C. Martin", url: "http://blog.cleancoder.com/uncle-bob/2017/05/05/TestDefinitions.htmll", likes: 10, __v: 0}, { _id: "5a422ba71b54a676234d17fb", title: "TDD harms architecture", author: "Robert C. Martin", url: "http://blog.cleancoder.com/uncle-bob/2017/03/03/TDD-Harms-Architecture.html", likes: 0, __v: 0}, { _id: "5a422bc61b54a676234d17fc", title: "Type wars", author: "Robert C. Martin", url: "http://blog.cleancoder.com/uncle-bob/2016/05/01/TypeWars.html", likes: 2, __v: 0}]
let result =_.map(_.countBy(blogs,'author'),(val,key)=>({author:key,blogs:val}))
const maxRes = _.maxBy(result, 'blogs');
console.log(maxRes);<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.21/lodash.min.js"></script>Does something like this solve your problem?
const author = "Robert C. Martin"
console.log({
author: author,
blogs: _.filter(blogs, (blog) => blog.author === author).length
})
Here's a link to a working example.