#how to extract a value from a key:value pair inside of an object that's inside of an array

145 messages · Page 1 of 1 (latest)

novel wing
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basically, i'm running a database querry that returns an array of results as an array and an object inside of the array for every matching result
it doesn't really matter that it's a databse though, that's not my concern, my concern is how to extract the values from a specific key for every single object that gets returned?
for example;

image.png
mighty owlBOT
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tall jasper
novel wing
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I haven't found how to extract a value from an object there though

tall jasper
novel wing
marble pastureBOT
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Documentation suggestion for @novel wing:
mdn Array.prototype.filter()
The filter() method of Array instances creates a shallow copy of a portion of a given array, filtered down to just the elements from the given array that pass the test implemented by the provided function.

tall jasper
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check if it‘s the right user using filter

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then map the resulting array

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more importantly though, you‘re running a database query, so if you‘re only interested in specific results, then you should modify your query to do that for you

novel wing
tall jasper
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and where’s the problem? I‘m having trouble understanding what you‘re stuck on

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what‘s the end result you want to get from the array of objects

novel wing
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but i also need to reply with a specific message if the array is empty (aka, if the user has no strikes)

tall jasper
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if you want to create one embedBuilder and append for each row of the array, there‘s also .reduce(), but I don‘t think that‘s even necessary in this case

novel wing
tall jasper
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because that‘s how an array is stringified

novel wing
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ah i see

tall jasper
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Array.isArray(variable) can also show if it‘s an array

novel wing
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yeah i know that but

tall jasper
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it‘s general fuckery because console.log() is not the same as array.toString()

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console.log() calls a formatting function

novel wing
tall jasper
novel wing
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i console.logged the result before that and it logged []

tall jasper
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essentially you're logging whether or not result and the newly created [] are stored at the same memory address, which is never possible

novel wing
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ohhh okay that makes sense

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one sec

novel wing
tall jasper
novel wing
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okay let me get back on track now

novel wing
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cause i would be sending out how many strikes a specific person has

tall jasper
novel wing
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if so then that's simpler than i thought lmfao

tall jasper
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out of curiosity, is javascript your first programming language?

novel wing
tall jasper
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discord.js is pretty complex for a starter project

novel wing
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it's not really my first project though

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plus im kind of forced to learn like 4 programming languages at once so lmfao 😭

tall jasper
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well, the length of an array exists in almost every programming language

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so that's why I suspected it

novel wing
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ah i see what you mean

novel wing
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i always

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tried to avoid fiddling around with complex array operations but

tall jasper
novel wing
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yes i know that

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okay hold on let me try something

novel wing
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or actually i might just use fields

tall jasper
novel wing
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this is purely me brainstorming but couldnt i make a for loop to make it add fields to the embed until it's at the last array index?

tall jasper
novel wing
tall jasper
# novel wing wdym

result array -> .map() to APIEmbedField {name: string, value: string, inline?: boolean} -> pass it to EmbedBuilder.addFields()

novel wing
tall jasper
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my bad, value*

novel wing
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or is this something else

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right

novel wing
tall jasper
novel wing
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i just

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don't know what APIEmbedField is supposed to mean

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im looking at the guide rn

tall jasper
novel wing
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i can explain more if you misunderstood because i might've not explained it the best 😅

tall jasper
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there's the upper limit of 25 due to how discord set that limit, but there's no limit for passing fields to the function

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it uses rest parameters / spread operator

novel wing
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like if i added 5 fields and someone only had 2 strikes for example

tall jasper
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if you loop over an array and are out of bounds, then you wrote your for loop wrong.

novel wing
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oh yeah about that pipeline

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oh wait im supposed to be using a for loop

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i moved it far out of the way lmfao one sec

tall jasper
novel wing
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oh

novel wing
tall jasper
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it can transform to ANY value. The function in map receives a strike object as parameter, and whatever you return ends up in the new array

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that includes transforming the strike object into an APIEmbedField

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If that confuses you, then I suggest looking up the following concepts

  • General: Callback Function
  • JavaScript: Arrow Function Syntax
novel wing
tall jasper
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correct!

novel wing
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meaning for me to add fields to an embed

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it would add a new field

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for every element in an array?

tall jasper
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map is specifically meant for returning the function's value

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it returns an array that has the same length as result, but each element within was changed according to the passed function

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in this case, it's function(id) { return id.strike_id; }

novel wing
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right so i need

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ok so basically

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what you're telling me i need to do is

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since an object is a single element in an array

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i need the function to extract the strike_id value from each object in an array, and then store it in a separate array

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?

tall jasper
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you need to take each strike object and change it into an APIEmbedField. Then you can return that newly created object

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since you now have an array of APIEmbedField, you can pass it to EmbedBuilder.addFields()

novel wing
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hmm wait i have an idea

novel wing
tall jasper
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since strike_id is a string

novel wing
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logged objewct

tall jasper
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oh that

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it‘s an array of strings

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arrays are objects in javascript so typeof logged that

novel wing
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ohhh

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okay

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OH okay i was

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thinking of something else

novel wing
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so

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const newID = result.map((id) => id.strike_id);
                                const newReason = result.map((strike) => strike.strike_reason);
                                for (let i = 0; i <= newID.length; i++) {
                                        yesStrikes.addFields(
                                            {title: `${newReason[i]}`, value: `${newID[i]}`}
                                        )
                                    }
tall jasper
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you can. There‘s always multiple ways

novel wing
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ah

tall jasper
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that code will fail though since i = newID.length is out of bounds

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remember, 0 indexed. So i goes from 0 to newID.length - 1

novel wing
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oh so

novel wing
tall jasper
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yes

novel wing
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OHH WAIT

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i set it to title: not name:

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i think

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oh okay that fixed it, thank you so much for the time <3

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I'll keep this open just in case I need something

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I'll close it later today

novel wing
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@tall jasper hey sorry for the ping but i have another question, i added a new column to the database which is date_issued which just stores a UNIX timestamp of when the command was ran.
Now when I try to print out those times on an embed using the same maping method as we described before, but it prints out the two values that are in the database for both cases, why is that?

image.png
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const newID = result.map((id) => id.strike_id);
const newReason = result.map((strike) => strike.strike_reason);
const newTime = result.map((time) => time.date_issued)
for (let i = 0; i < newID.length; i++) {
  yesStrikes.addFields(
    { name: `${newReason[i]}`, value: `Strike ID: ${newID[i]} | <t:${newTime}>` }
  )
}
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Sorry for the ping btw

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never the fuck mind im blind as fuck

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i swear to god i ask for help and as soon as i do it clicks

tall jasper
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get a rubber duck so you can ask it first

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if it clicks immediately, it‘ll work