CMake to tweak about JSON strings

test-json.cmake

cmake_minimum_required(VERSION 3.19)

include(CMakePrintHelpers)

message(STATUS START)

set(jsonContent
[[
{
    "key1": 123,
    "key2": [4, 5, "test"],
    "one": {
        "two": {
            "three": ["x", "y", "z"]
        }
    }
}
]]
)

message(STATUS "Get key1")
string(JSON outVar ERROR_VARIABLE errorVar GET ${jsonContent} key1)
cmake_print_variables(errorVar outVar)

message(STATUS "Set key2.[1]")
string(JSON outVar ERROR_VARIABLE errorVar SET ${jsonContent} key2 1 [["hello"]])
cmake_print_variables(errorVar outVar)

message(STATUS "Get key2.[1]")
string(JSON outVar ERROR_VARIABLE errorVar GET ${jsonContent} key2 1)
cmake_print_variables(errorVar outVar)

message(STATUS "Set one.two.three.[2]")
string(JSON outVar ERROR_VARIABLE errorVar GET ${jsonContent} one two three 2)
cmake_print_variables(errorVar outVar)