How VSCode parses json files like language-configuration.json that is used to describe language extensions? I see that these files contain comments and many, like typescript, contain trailing commans.
If such content is parsed using JSON.parse() the error will be raised.
I implement an extension that reads these config files and like to use the same parsing method that is used in vscode.
Thank you
I would assume they use the jsonc-parser - since it is written by one of the vscode team and has 3 million+ downloads a week.
npm package: jsonc-parser
I use it myself because I need to parse complicated custom settings that might have comments in them for example.
Add the package to your dependencies. npm install --save jsonc-parser
Then import it (I have it in a js extension for now):
const jsonc = require("jsonc-parser");
const rootNode = jsonc.parseTree(document.getText());
Related
I'm trying to require some JSON files in my React app (based on CRA 3.01 with Typescript).
The normal const obj = require('./path/file.json') would work if my files had a .json extension - however, these files have .md for 'metadata' and a couple other extensions, and the standard require isn't working. The files are from a tool, so changing to .json isn't a practical option.
Doing some research, it seems the approach is to use the webpack json-loader module (the webpack json-loader docs says that working with different file extensions is the main reason for using the module). I found an example and am using this:
const context = require.context(
"json-loader!./metadata",
true,
/^\.\/.*\.md$/
);
const metadata = context("./foo.md");
I've got a minimum reproduction here (see App.tsx):
https://github.com/ericsolberg/testjson
It seems that this is correctly using the json-loader, and finding the file correctly. However, I'm getting a syntax error:
Error: Module build failed (from ./node_modules/json-loader/index.js):
SyntaxError: Unexpected token m in JSON at position 0
at JSON.parse (<anonymous>)
at Object.module.exports (/Users/***/projects/jsontest/node_modules/json-loader/index.js:4:49)
I did some research on this error, and believe the problem is that the file is being parsed twice - first by the loader configured by CreateCreactApp's default webpack config, then by the specified JSON loader.
I don't want to eject my CRA app to modify the webpack config, and would like to avoid a re-wire hack (and whatever other issues that introduces) ... does anyone know of a way to load JSON files in a CRA app, if these files don't have a JSON extension?
Here's the solution that ended up working for me.
I could eject my project, of course, and customize the webpack config to load JSON files with other extensions. It may be possible to make a rewire hack work as well.
But I realized that when I require a file that is not one of the extensions recognized by CRA's config, it instead copies that file into the build, and require('file.ext') returns the URL of the file. So I'm using axios to load the file. This means a trip to the server for something that could be done statically, but for where I'm taking this project that is actually OK (eventually it will load metadata from a server anyway).
Will importing local json/text like the following I have written below be async or sync in Create-React-App?
import SampleLocalJson from './sample/sampleJson.json'
This depends on your environment. If you are using webpack >=v2.0.0 (which you probably do if the above line works) this will be done automatically by webpack json-loader during build time and is therefore sync.
If you are not on webpack >=v2.0.0 there can be multiple issues with directly importing json. Here is a good thread about it: How to import a json file in ecmascript 6?
UPDATE
If you are interested in lazy loading the json, there is support for that built in to webpack. They have a good example in their documentation on that.
This is handled by webpack during the build time. That JSON becomes part of your bundle file shipped to the browser.
i am building an extension to parse json using vs code extension.
so my need is ,it should be able able to load .json file from a particular folder and iterate through content of the file.
Then it should allow user to select few keys from it make a new json file out of this and save it in any folder.
But i am not able to find any way to read and write files in "vs code extension".Could someone please help me.
If you want to read the current edit state of a file you can use the following API workspace function:
vscode.workspace.openTextDocument(uri).then((document) => {
let text = document.getText();
});
This will show you the current state of the file including unpersisted changes. document is of type TextDocument and has isDirty set to true if it has pending changes.
Since the extension runs in nodejs, you should be able to use any nodejs module built-in or installed by npm in the usual way.
For your purpose you will be OK with the built-in fs module: https://nodejs.org/dist/latest-v6.x/docs/api/fs.html
In your extension you will need to import the required module, so your code file should contain this:
let fs = require("fs");
and then use the methods in the usual way, eg. fs.fileReadSync( filename, encoding ) ...
Please not that there is one exception. If you install a nodejs module containing compiled, binary code, it will not run in the extension and instead you will see an error message saying something like %1 is not a valid Win32 application. Pure javascript modules are OK, though.
VSCode extensions are running in node.js. Therefore you can use any available node.js package/module within your extension. For instance, check out this question for reading JSON.
For JSON, you just need to require or import the JSON file, such as:
const jsonObject = require('./myJSONfile.json');
// do something
For JSON with comments, you can use node-jsonc-parser.
After the manipulation, you could use the fs module of nodej.js to write to the disk.
I'm writing a simple Erlang program that requests an URL and parses the response as JSON.
To do that, I need to use a Library called Jiffy. I downloaded and compiled it, and now i have a .beam file along with a .app file. My question is: How do I use it? How do I include this library in my program?. I cannot understand why I can't find an answer on the web for something that must be very crucial.
Erlang has an include syntax, but receives a .hrl file.
Thanks!
You don't need to include the file in your project. In Erlang, it is at run time that the code will try to find any function. So the module you are using must be in the search path of the VM which run your code at the point you need it, that's all.
For this you can add files to your path when you start erlang: erl -pa your/path/to/beam (it exists also -pz see erlang doc)
Note that it is also possible to modify the path from the application itself using code:add_path(Dir).
You should have a look to the OTP way to build applications in erlang documentation or Learn You Some Erlang, and also look at Rebar a tool that helps you to manage erlang application (for example starting with rebar or rebar wiki)
To add to Pascal's answer, yes Erlang will search for your files at runtime and you can add extra paths as command line arguments.
However, when you build a project of a scale that you are including other libraries, you should be building an Erlang application. This normally entails using rebar.
When using rebar, your app should have a deps/ directory. To include jiffy in your project, it is easiest to simply clone the repo into deps/jiffy. That is all that needs to be done for you to do something like jiffy:decode(Data) in your project.
Additionally, you can specify additional include files in your rebar.config file by adding extra lines {erl_opts, [{i, "./Some/path/to/file"}]}.. rebar will then look for file.so using that path.
I want to use BIRT to generate reports against data that comes from a JSON based REST API. How can I import this data?
The process for doing this is described at http://developer.actuate.com/community/forum/?app=blog&blogid=45&showentry=471, but it turns out that there are a few important steps missing. I'll fill in a few blanks here.
The original instructions describe creating a Scripted Data Source, with an "open" script that makes use of the com.actuate.json.JSONParser class. First, it is important to realise that this class is not part of BIRT, and needs to be manually added (along with any dependencies).
The download provided by the original instructions provides the com.actuate.json.JSONParser class, but leaves it up to you to source the dependencies. To make things easier I have reimplemented the JSONParser library in Maven, which will then download and package the dependencies for you. It also includes some bug fixes and enhancements like GZIP compression support. You can get the Maven project from https://github.com/mcasperson/birt-jsonparser, and to build the JSONParser library and package the dependencies, run the command
mvn clean package dependency:copy-dependencies
This will result in the birt-jsonparser-0.0.1-SNAPSHOT.jar file being created in the target directory, and all the dependencies copied into the target\dependency directory. Copy all of these JAR files into the {BIRT_INSTALL}/plugins/org.eclipse.birt.report.viewer_{BIRT_VIEWER_VERSION}/birt/scriptlib directory to allow the JSONParser class to be accessed from within your BIRT report.
If you want to debug your report, these JAR files will also have to be referenced in the Debug profile.