How to choose where to append data? - javascript

How do I choose where to append data with fs.appendFileSync()?
My current code:
var fd = fs.openSync('test.js', 'a');
fs.appendFileSync('test.js', "/**/");
fs.closeSync(fd);
This just appends the data at the end of the file. The options object gives me no way to choose where to append it.

fs.appendFileSync() can only append data to the end of the file. It does not have the option you are asking for.
In fact, the only way (with a normal file system) to insert data into the middle of a file is to rewrite data that is in the file to move it later in the file and then write to the block where you want the new data to go. For this, you would use fs.read() and fs.write() passing it the desired file positions.

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How to create a function that returns an array of image paths in javascript?

How can I create a function that loops through a folder in my directory called "data." It contains only image files, and I will keep adding more image files to it. Previously, I was using the following function that returns an array of URLs:
function _image_urls(){return(
[
"https://images.pexels.com/photos/4050284/pexels-photo-4050284.jpeg?auto=compress&cs=tinysrgb&w=1260&h=750&dpr=1",
"https://images.pexels.com/photos/1323550/pexels-photo-1323550.jpeg?auto=compress&cs=tinysrgb&w=600",
"https://images.pexels.com/photos/2002719/pexels-photo-2002719.jpeg?auto=compress&cs=tinysrgb&w=1260&h=750&dpr=1",
"https://images.pexels.com/photos/919606/pexels-photo-919606.jpeg?auto=compress&cs=tinysrgb&w=600",
"https://images.pexels.com/photos/1983038/pexels-photo-1983038.jpeg?auto=compress&cs=tinysrgb&w=1260&h=750&dpr=1",
"https://images.pexels.com/photos/1702624/pexels-photo-1702624.jpeg?auto=compress&cs=tinysrgb&w=1260&h=750&dpr=1",
"https://images.pexels.com/photos/3631430/pexels-photo-3631430.jpeg?auto=compress&cs=tinysrgb&w=1260&h=750&dpr=1",
"https://images.pexels.com/photos/5011647/pexels-photo-5011647.jpeg?auto=compress&cs=tinysrgb&w=1260&h=750&dpr=1",
"https://images.pexels.com/photos/135018/pexels-photo-135018.jpeg?auto=compress&cs=tinysrgb&w=1260&h=750&dpr=1",
"https://images.pexels.com/photos/161154/stained-glass-spiral-circle-pattern-161154.jpeg?auto=compress&cs=tinysrgb&w=1260&h=750&dpr=1"
]
)}
I'm trying to create a function that returns an array of paths for all the images in the data folder. I have been trying the following approach:
function _image_urls(){
const image_folder = 'data';
const image_extension = '.jpg';
let image_urls = [];
for (let i = 0; i < 10; i++) {
let image_url = image_folder + i + image_extension;
image_urls.push(image_url);
}
return image_urls;
}
It seems like this will just return an array like:
[
"data0.jpg",
"data1.jpg",
"data2.jpg",
"data3.jpg",
"data4.jpg",
"data5.jpg",
"data6.jpg",
"data7.jpg",
"data8.jpg",
"data9.jpg"
]
If that's what you're getting, then you need to use i as the index for an array that contains the file names.
The bigger question is how are you getting that list of files in the first place? This is generally not something that JavaScript can do on its own. If the files exist on the server, you'd need some server-side script to actually access the folder and output the array of file names - this can then be put into an array several ways (either writing it directly to the code if you allow your server side code to process the JS file or probably more likely using an XHR to request the file names and then populate the array when you get the response.)
If you write this server side script such that it formats the output as JSON, then it could simply be a matter of using JSON.parse() to convert the output to an array directly without any need to iterate over the response such as the function in the question.
EDIT/UPDATE after comment from OP:
Since you're using PHP on the server side, I would create a server side script that readers the contents of the "Data" folder and outputs a JSON formatted string which can then be parsed by the JS on the front end.
In general, this is done using the scandir function. See https://www.php.net/manual/en/function.scandir.php for details.
and the steps would be as follows:
Use scandir to get an array of files in the Data folder
Remove the first two items in the array (. and ..)
Use the json_encode function to convert the array to a JSON formatted string
Echo that string
Then on the page where you have your JS you have two options:
Include the PHP script described above such that it becomes a JS array using JSON.parse().
Use an XHR to request the PHP script, and when you get a response use JSON.parse() to set it as an array variable.
The first method is outdated, but very simple - though it does require that your JS code is parsed by PHP which may or may not be possible/advisable depending on your server configuration.
The second method is probably what you should do, as long as you're fine with the array being populated after the page loads and that you wait for the XHR to complete before calling any functions that rely on the array.
The main thing to know here is that what you want to do is not possible using only JavaScript because JS cannot read the contents of a folder on the server. Your JS will need to interact with some server side code in order to read the contents of a folder into any array.

Generate Table/Grid from script in Adobe InDesign

Documentation doesn't help at all,no Table or Grid is specified...(or I cant find it)
I tried to create a grid from inside InDesign and it shows up as TextFrame,but still I dont understand how to manage it.
The tool I need to do takes a file(CSV/JSON) and generates a Table(or whatever is called in Adobe) from it,but the problem is that I can't find anything about Table generation.
Basically you can make a table from a selected text with the method convertToTable() this way:
var doc = app.activeDocument; // your document
var frame = doc.pages[0].textFrames[0]; // first text frame on first page
frame.texts.everyItem().select(); // select all text inside the frame
var table = app.selection[0].convertToTable(); // convert the selection into a table
Before:
After:
Reference:
Text object
As for the rest... it's need more details about your workflow. JSON and CSV are quite different beasts, it would be different parsing algorithms for each of the formats. Will you copy the contents of the files manually or the script should read all csv or json files from some predefined folder? Or there should be some interface to select a file(s). Or a folder? How it supposed to handle a page size and formatting of the table? Etc...

Tabulator combine multiple tables in a single pdf

I am using http://tabulator.info/ to generate multiple tables on a single HTML document page.
When I am triggering the pdf-download via the button, a pdf document should get generated that includes the tables from the document.
So far, downloading a single table works, but I don't know how I could potentially add more tables to the document before jsPDF finishes.
What I have tried out so far is that I grabbed the lastTable1 = doc.lastAutoTable object inside the documentProcessing function when triggering a download for table1. The plan is to pass it into table2.download() and add it via autoTable: function(doc){doc.autoTable(lastTable1)}.
While I do grab an object with this approach, I can not use it to reconstruct the autotable object (e.g. doc.autoTable(lastTable1) does not produce the same table again).
I have prepared a simple jsfiddle where I generate two tables and a download button. Just to illustrate that the reconstruction of the autotable object does not work, I have added it once more to the doc before creating the pdf.
There is no built in way for tabulator to do this.
But the good news is that it should be easy to add something to handle this yourself.
This Issue shows how you can use jsPDF to merge to PDFs into the same document.
You could use the downloadReady callback built into tabulator to intercept the PDF file created from each table and then combine them using the method outlined in the above issue
var table = new Tabulator("#example-table", {
downloadReady:function(fileContents, blob){
//fileContents - the unencoded contents of the file
//blob - the blob object for the download
mergeWithPreviousPDFs(blob); // call a function based on the previous issue that merges the new PDF with the previous PDF's
return blob; //must return a blob to proceed with the download, return false to abort download
}
});
if you return false from this callback the download will not be triggered, so you can intercept the PDF output on all but the final table to prevent download and then return the combined output from the last table to trigger the download.

Importing text file contents to database

I'm working with sensor units outfield that spit out data in the form of native text files and have a database created with pre-defined tags. E.G mm, level, voltage. The text file I'm using is pretty unstructured with the data being on the right side of the header separated by semicolon delimiters.
I want to try and import the content into the database where each header matches the tag name and the values are inserted into that tag consecutively. I'm wondering if there's a possible solution or maybe even some tips on how i can achieve this?
Currently i have been working with PHP but haven't gotten to far, is it the best language to use for such a method? Or would javascript be preferred?
Text file is delimited by semicolons:
L;MINVi;Min voltage;V;PTi;Processor temperature;C;AVGVi;Average voltage;V;SDB;Network signal dB;dB;WL02;waterlevel 2m;cm;RSSI;Network signal indication;RSSI;OCi;Operating cycle;sec;SCNT;Satellites;;LAT;Latitude;deg;LON;Longitude;deg
S;170427000428;ERR;SERVER_LOGIN;+CME ERROR: Bad or no response from server
S;170427000428;ERR;FTP
S;170427000450;ALARM_SEND_OK
S;170427000510;WDT;GPS
D;170427000510;SCNT;0*T;LAT;0*T;LON;0*T
S;170427000518;ERR;SERVER_LOGIN;+CME ERROR: Bad or no response from server
S;170427000518;ERR;FTP
S;170427000647;ERR;SERVER_LOGIN;+CME ERROR: Bad or no response from server
S;170502171807;POWER_ON;ML-315;V2.7B1
S;170502171807;SYS_START;BHSDemo 5170991
D;170502171817;MINVi;3.66;PTi;25.8;AVGVi;3.71;WL02;2.86*A;OCi;9.95
S;170502171822;WDT;MODEM_INIT
D;170502171823;SDB;0*T;RSSI;0*T
S;170502171823;WDT;Network signal
database table Tag_data Structure
You can do like this
LOAD DATA INFILE '/yourtext.txt' INTO TABLE TABLENAME;
Your text will be pretty hard to explode every value with it's parameter because every single word end with ; so, first try to make your text file like parameter:value; or parameter=value; or parameter_value; then you can read the content of this file with this php function $content = file_get_contents("path/text_file_name.txt"); now the value of $content variable is equal to the entire text of your file hence, you can split this variable into an array with $splittedcontent = explode(";" , $content); every parameter:value is a parameter in this array like $splittedcontent[0] = parameter0:value0, $splittedcontent[1] = parameter1:value1 and so on, now you can use for loop throw this array and make what your need in you database..
I hope this will help you.

Getting all of the .json files from a directory

I'm creating an android app which takes in some json data, is there a way to set up a directory such as;
http://......./jsons/*.json
Alternatively, a way to add into a json file called a.json, and extend its number of containing array data, pretty much add more data into the .json file this increase its size.
It could be by PHP or Javascript.
Look into Parsing JSON, you can use the JSON.parse() function, in addition, I'm not sure about getting all your JSON files from a directory call, maybe someone else will explain that.
var data ='{"name":"Ray Wlison",
"position":"Staff Author",
"courses":[
"JavaScript & Ajax",
"Buildinf Facebook Apps"]}';
var info = JSON.parse(data);
//var infostoring = JSON.stringify(info);
One way to add to a json file is to parse it, add to it, then save it again. This might not be optimal if you have large amounts of data but in that case you'll probably want a proper database anyway (like mongo).
Using PHP:
$json_data = json_decode(file_get_contents('a.json'));
array_push($json_data, 'some value');
file_put_contents('a.json', json_encode($json_data));

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