Error occured while trying to proxy: localhost:3000/ code example

Example 1: Error occurred while trying to proxy to: localhost:3000/

{
"/api": {
"target": "https://localhost:12345",
"secure": false,
"changeOrigin": true
}
}

Example 2: Error occurred while trying to proxy to: localhost:3000/

{
  "*": {
    "target": "[::1]:8080/",
    "secure": true,
    "logLevel": "debug",
    "changeOrigin": true,
    "headers": {
      "Connection": "keep-alive"
    },
    "pathRewrite": { "^/*": "" }
  }
}