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Variable Changing Value On It's Own Javascript

I have formatted a string to be used within a putItem call using DynamoDB SDK. This Long string (item I would like to add has lots of information) is stored in a variable and I should be able to use it within the Item {} part of dynamoDdb.putItem() .
However, when the variable is actually processed extra characters are added in causing the formatting to be incorrect for how an Item {} should look.
See below:
itemToAdd = JSON.stringify(marshalled2, null,2)
newString = itemToAdd.slice(4, itemToAdd.length-1)
correct = newString.replaceAll(" ", '');
correct2 = correct.replaceAll("\n", "")
//console.log(newString)
var params = {
TableName: "Music",
Item: {
correct2
}
}
dynamodb.putItem(params, function(err, data) {
if (err) {
console.log("Error", err);
} else {
console.log("Success", data);
}
});
My issue is that the string correct2 has no slashes or \n in it as I have removed them prior however when the string correct2 is used with the params object extra black slashes have been added into the string messing up the formatting.
An example of the string contained in correct2 would be as follows:
"AlbumData":{"S":"2B5C1828-6077-4ED1-89AD-13602A7AC08D"},"label":{"S":"EvolutionMediaMusic"},"Album":{"S":"BleakDrama"},"albumCode":{"S":"EMM101"},"releaseDate":{"S":"21/06/2016"},"description":{"S":"Contemporarynoircrimedrama:coldandforebodingcueswithtwistedsyntheticatmospheresandpulsingrhythms."},"credits":{"S":""},"tracks":{"L":[{"M":{"id":{"S":"984CA56C-3FA8-4F49-9C9E-3F96C237EE7E"},"trackNo":{"S":"1"},"albumCode":{"S":"EMM101"},"albumName":{"S":"BleakDrama"},"lengthOfTrack":{"S":"02:30"}, //more fields would go here
If I was to copy the text above and insert it into where the variable is there is no issue with the code. Using the javascript debug console the variable correct2 is set to the above however
params.Item = \"AlbumData\":{\"S\":\"2B5C1828-6077-4ED1-89AD-13602A7AC08D\"},\"label\":{\"S\":\"EvolutionMediaMusic\"},\"Album\":{\"S\":\"BleakDrama\"}, // and the patten repeats
What is causing the difference between correct2 and params.Item? I would expect them to be the same.

Dude, its ok, just relax. Its called escaping
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String#escape_sequences
https://www.geeksforgeeks.org/how-to-use-escape-characters-to-correctly-log-quotes-in-a-string-using-javascript/

How can I convert this text to JSON by nodejs?

How can I convert this text to JSON by nodejs?
Input :
---
title:Hello World
tags:java,C#,python
---
## Hello World
```C#
Console.WriteLine(""Hello World"");
```
Expected output :
{
title:"Hello World",
tags:["java","C#","python"],
content:"## Hello World\n```C#\nConsole.WriteLine(\"Hello World\"");\n```"
}
What I've tried to think :
use regex to get key:value array, like below:
---
{key}:{value}
---
then check if key equals tags then use string.split function by , to get tags values array else return value.
other part is content value.
but I have no idea how to implement it by nodejs.

If the input is in a known format then you should use a battle tested library to convert the input into json especially if the input is extremeley dynamic in nature, otherwise depending on how much dynamic is the input you might be able to build a parser easily.
Assuming the input is of a static structure as you posted then the following should do the work
function convertToJson(str) {
const arr = str.split('---').filter(str => str !== '')
const tagsAndTitle = arr[0]
const tagsAndTitleArr = tagsAndTitle.split('\n').filter(str => str !== '')
const titleWithTitleLabel = tagsAndTitleArr[0]
const tagsWithTagsLabel = tagsAndTitleArr[1]
const tagsWithoutTagsLabel = tagsWithTagsLabel.slice(tagsWithTagsLabel.indexOf(':') + 1)
const titleWithoutTitleLabel = titleWithTitleLabel.slice(titleWithTitleLabel.indexOf(':') + 1)
const tags = tagsWithoutTagsLabel.split(',')
const result = {
title: titleWithoutTitleLabel,
tags,
content: arr[1].slice(0, arr[1].length - 1).slice(1) // get rid of the first new line, and last new line
}
return JSON.stringify(result)
}
const x = `---
title:Hello World
tags:java,C#,python
---
## Hello World
\`\`\`C#
Console.WriteLine(""Hello World"");
\`\`\`
`
console.log(convertToJson(x))

Looks like you're trying to convert markdown to JSON. Take a look at markdown-to-json.
You can also use a markdown parser (like markdown-it) to get tokens out of the text which you'd have to parse further.

In this specific case, if your data is precisely structured like that, you can try this:
const fs = require("fs");
fs.readFile("input.txt", "utf8", function (err, data) {
if (err) {
return console.log(err);
}
const obj = {
title: "",
tags: [],
content: "",
};
const content = [];
data.split("\n").map((line) => {
if (!line.startsWith("---")) {
if (line.startsWith("title:")) {
obj.title = line.substring(6);
} else if (line.startsWith("tags")) {
obj.tags = line.substring(4).split(",");
} else {
content.push(line);
}
}
});
obj.content = content.join("\n");
fs.writeFileSync("output.json", JSON.stringify(obj));
});
Then you just wrap the whole fs.readFile in a loop to process multiple inputs.
Note that you need each input to be in a separate file and structured EXACTLY the way you mentioned in your question for this to work. For more general usage, probably try some existing npm packages like others suggest so you do not reinvent the wheel.

Import text json for node js template literals

For my node js projects i typically have a text.json file and require it, instead of having static text within my code. something like below
JSON file
{
"greet":"Hello world"
}
var text = require('./text.json');
var greet = text.greet
I am having a little trouble in figuring out how this would work with template literals ?

I know this is an old issue but I just came up with a need for the same thing and.. yeah there are node modules that help do this but, this isn't that complex so I just made my own solution
function injectVariables( replacements, input ) {
const entries = Object.entries(replacements)
const result = entries.reduce( (output, entry) => {
const [key, value] = entry
const regex = new RegExp( `\\$\{${key}\}`, 'g')
return output.replace( regex, value )
}, input )
return result
}
const template = 'Hello my name is ${name} and I like ${language}'
const inputs = { name: 'David', language: 'JavaScript' }
const replaced = injectVariables(inputs, template)
console.log(replaced)
So, in this, it takes an input string and an object where the keys are the variable names in the string and the values are, you guessed it, the values.
It creates an array the values using Object.entries and then runs reduce across the entries to keep an updated version of the string as you go. On each iteration it makes a regex to match the variable expression and replaces that value with the one passed it.
This in particular won't look through nested objects (I didn't need that) but if for example your string had ${name.last} in it, since object keys can be strings, your input variable could be inputs = { 'name.last': 'Smith' } and it should work.
Hopefully this helps someone else.

I often use a very tiny templating helper library (tim - https://github.com/premasagar/tim) and it can be used to accomplish this:
//in my json file
var strings = {
'Hello': 'Hello {{name}}!',
'Goodbye': 'Goodbye {{name}}!'
};
//in my app
var tim = require('tim'); //templating library
var strings = require('./strings.json');
//replace
console.log(tim(strings.Hello,{name:'Fred'}));
Relevant JSFiddle:
https://jsfiddle.net/rtresjqv/
Alternatively, you could turn your strings into functions and then pass in the arguments:
//in my json file
var strings = {
'Hello': function() { return `Hello ${arguments[0]}!`; },
'Goodbye': function() { return `Goodbye {$arguments[0]}!`; }
};
//in my app
var strings = require('./strings.json');
//replace
console.log(strings.Hello('Fred'));
Fiddle:
https://jsfiddle.net/t6ta0576/

Replacing values in JSON object

I have the following JSON object data returned from my apicontroller :
[
{"id":2,"text":"PROGRAMME","parent":null},
{"id":3,"text":"STAGE","parent":2},
{"id":4,"text":"INFRA","parent":2},
{"id":5,"text":"SYSTEM","parent":3},
{"id":6,"text":"STOCK","parent":3},
{"id":7,"text":"DPT","parent":3},
{"id":9,"text":"EXTERNAL","parent":null}
]
I want to replace "parent":null with "parent":'"#"'
I have tried the code below, but it is only replacing the first occurrence of "parent":null. How can I replace all "parent":null entries?
$(document).ready(function () {
$.ajax({
url: "http://localhost:37994/api/EPStructures2/",
type: "Get",
success: function (data) {
var old = JSON.stringify(data).replace(null, "'#'"); //convert to JSON string
var new = JSON.parse(old); //convert back to array
},
error: function (msg) { alert(msg); }
});
});
Thanks,

You need to make the replace global:
var old = JSON.stringify(data).replace(/null/g, '"#"'); //convert to JSON string
var newArray = JSON.parse(old); //convert back to array
This way it will continue to replace nulls until it reaches the end
Regex docs:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp
Also, as a side note, you should avoid using new as a variable name as it is a reserved word in javascript and most browsers will not allow you to use it

#JonathanCrowe's answer is correct for regex, but is that the right choice here? Particularly if you have many items, you'd be much better off modifying the parsed object, rather than running it through JSON.stringify for a regex solution:
data.forEach(function(record) {
if (record.parent === null) {
record.parent = "#";
}
});
In addition to being faster, this won't accidentally replace other nulls you want to keep, or mess up a record like { text: "Denullification Program"}.

Backbone.js - Filter a Collection based on an Array containing multiple keywords

I'm using Backbone.js/Underscore.js to render a HTML table which filters as you type into a textbox. In this case it's a basic telephone directory.
The content for the table comes from a Collection populated by a JSON file.
A basic example of the JSON file is below:
[{
"Name":"Sales and Services",
"Department":"Small Business",
"Extension":"45446",
},
{
"Name":"Technical Support",
"Department":"Small Business",
"Extension":"18800",
},
{
"Name":"Research and Development",
"Department":"Mid Market",
"Extension":"75752",
}]
I convert the text box value to lower case and then pass it's value along with the Collection to this function, I then assign the returned value to a new Collection and use that to re-render the page.
filterTable = function(collection, filterValue) {
var filteredCollection;
if (filterValue === "") {
return collection.toJSON();
}
return filteredCollection = collection.filter(function(data) {
return _.some(_.values(data.toJSON()), function(value) {
value = (!isNaN(value) ? value.toString() : value.toLowerCase());
return value.indexOf(filterValue) >= 0;
});
});
};
The trouble is that the function is literal. To find the "Sales and Services" department from my example I'd have to type exactly that, or maybe just "Sales" or "Services". I couldn't type "sal serv" and still find it which is what I want to be able to do.
I've already written some javascript that seems pretty reliable at dividing up the text into an array of Words (now updated to code in use).
toWords = function(text) {
text = text.toLowerCase();
text = text.replace(/[^A-Za-z_0-9#.]/g, ' ');
text = text.replace(/[\s]+/g, ' ').replace(/\s\s*$/, '');
text = text.split(new RegExp("\\s+"));
var newsplit = [];
for (var index in text) {
if (text[index]) {
newsplit.push(text[index]);
};
};
text = newsplit;
return text;
};
I want to loop through each word in the "split" array and check to see if each word exists in one of the key/values. As long as all words exist then it would pass the truth iterator and get added to the Collection and rendered in the table.
So in my example if I typed "sal serv" it would find that both of those strings exist within the Name of the first item and it would be returned.
However if I typed "sales business" this would not be returned as although both the values do appear in that item, the same two words do not exist in the Name section.
I'm just not sure how to write this in Backbone/Underscore, or even if this is the best way to do it. I looked at the documentation and wasn't sure what function would be easiest.
I hope this makes sense. I'm a little new to Javascript and I realise I've dived into the deep-end but learning is the fun part ;-)
I can provide more code or maybe a JSFiddle if needed.

Using underscore's any and all make this relatively easy. Here's the gist of it:
var toWords = function(text) {
//Do any fancy cleanup and split to words
//I'm just doing a simple split by spaces.
return text.toLowerCase().split(/\s+/);
};
var partialMatch = function(original, fragment) {
//get the words of each input string
var origWords = toWords(original + ""), //force to string
fragWords = toWords(fragment);
//if all words in the fragment match any of the original words,
//returns true, otherwise false
return _.all(fragWords, function(frag) {
return _.any(origWords, function(orig) {
return orig && orig.indexOf(frag) >= 0;
});
});
};
//here's your original filterTable function slightly simplified
var filterTable = function(collection, filterValue) {
if (filterValue === "") {
return collection.toJSON();
}
return collection.filter(function(data) {
return _.some(_.values(data.toJSON()), function(value) {
return partialMatch(value, filterValue);
});
});
};
Note: This method is computationally pretty inefficient, as it involves first looping over all the items in the collection, then all the fields of each item, then all words in that item value. In addition there are a few nested functions declared inside loops, so the memory footprint is not optimal. If you have a small set of data, that should be OK, but if needed, there's a number of optimizations that can be done. I might come back later and edit this a bit, if I have time.
/code samples not tested