VS Code - Launch.Json and App.Json file parameters

 This blog is content detail about all parameter detail about this 2 important configuration file.

Json Configuration Files

JSON stands for JavaScript Object Notation, which is a lightweight data interchange format, often used for storing and transporting data. In an AL project there are two JSON files: the app.json file and the launch.json file. These files are automatically created when you start a new AL project. These files are used to store configuration data about your AL project. The app.json file contains information about the extension you are building, such as publisher information, the name and the version of the extension.

Launch.json file

The launch.json is a configuration file that contains information about the server that the extension launches on. There are two configurations depending on whether the extension is published to a local server or to the cloud.

Let’s discuss some important and mandatory properties.

Publish to local server settings

Setting	Mandatory	Value
name	Yes	Name of your configuration, for example "Local dev server"
type	Yes	Must be set to “.al”. Required by Visual Studio Code
request	Yes	Must be set to “launch”. Required by Visual Studio Code
server	Yes	The HTTP URL of your server, for example “http://localhost”
serverInstance	Yes	The instance name of your server, for example: “D365”
authentication	Yes	Specified the server authentication method
startupObjectId	Yes	Specified the ID of the object to open after publishing. Only objects of type Page and Table are currently supported
startupObjectType	Yes	Specifies with type of object to open after publishing. This is used in combination with the setting “startupObjectId”. Only objects of type Page and Table are currently supported
schemaUpdateMode	No	Specifies the data synchronization mode when you publish an extension to the development server: "Synchronize” or “Recreate". The default value is Synchronize. With Synchronize the existing data is kept, while Recreate will delete the existing data.

Publish to cloud settings

Setting	Mandatory	Value
name	Yes	Name of your configuration, for example "Local dev server"
type	Yes	Must be set to “.al”. Required by Visual Studio Code
request	Yes	Must be set to “launch”. Required by Visual Studio Code
serverInstance	Yes	The instance name of your server, for example: “US”
startupObjectId	Yes	Specified the ID of the object to open after publishing. Only objects of type Page and Table are currently supported
startupObjectType	Yes	Specifies with type of object to open after publishing. This is used in combination with the setting “startupObjectId”. Only objects of type Page and Table are currently supported

App.json file 

The app.json file contains information about the extension that you are building, such as publisher information, name and the minimum supported version. Often the app.json file is referred to as the manifest.

Setting	Mandatory	Value
id	Yes	The unique ID of the extension. When the app.json file is automatically created, the ID is set to a new GUID value
name	Yes	The unique extension name
publisher	Yes	The publisher name
brief	No*	Short description of the extension
description	No*	Longer description of the extension
version	Yes	The version of the app package
platform	Yes	The minimum supported version of the platform symbol package file
application	Yes	The minimum supported version, for example “application”: “11.0.0.0”
idRange	Yes	A range for application object IDs. Objects outside the range will raise a compilation error. A new ID is automatically suggested. The allowed range is provided to you from Microsoft.