example4

Example 4 - Modify the CLI to validate that the input is of JSON format

This simple CLI requests input for a file that's contents match a specific format structure:

{
    "title": "Workshop Title",
    "instructors": [
        {
            "name": "Instructor 1",
            "email": "instructor1@example.com"
        },
        {
            "name": "Instructor 2",
            "email": "instructor2@example.com"
        }
    ]
}

If the input file validates against this structure then the data is extracted and printed out, otherwise the application will exit 1.

Usage

To use this program, build the cli.go file:

$ go build cli.go // Unix, Linux $ go build -o cli.exe cli.go // Windows

This will create an executable file named cli in the current directory. You can then run the program with the ./cli command and provide the file flag to print its contents:

./cli -file <filename> // Unix, Linux .\cli.exe -file <filename> // Windows

Replace <filename> with the name of the file you want to read.

If the file cannot be opened or read, an error message will be printed and the program will exit 1. If the file can be read, the file's contents will be printed out.