Feature: template blocks in JavaScript, Python, etc.

[juanMarinero]

Issues

• I have checked existing issues and there are no existing ones with the same request.

Feature description

https://www.jetbrains.com/help/idea/exploring-http-syntax.html#response-handling states:

You can handle the response using JavaScript. Type the > character after the request and specify the path and name of the JavaScript file or put the response handler script code wrapped in {% ... %}.

This does not apply to this plugin (I think). Only Lua is practical in template blocks.
I.e. there is no direct JavaScript equivalent to request.variables.set. Nor for Python, etc.

Below I coded how to workaround with io.popen, but I insist, this is a workaround.

With Lua it's easy:

# @lang=lua
< {%
  -- Install base64 library
  --   sudo luarocks install base64

  local base64 = require("base64")
  local encoded = base64.encode("user:passwd")
  -- Set variables directly in the context
  request.variables.set("authHeader_Local_02", encoded)
%}
// Request (200)
GET https://httpbin.org/basic-auth/user/passwd
Authorization: Basic {{authHeader_Local_02}}
###

Pseudo-JavaScript: base64 user-pass for test JS in template blocks

# @lang=lua
< {%
  -- Use Lua to execute a Node.js command and capture its output
  local handle = io.popen('node -e "console.log(\\\"dXNlcjpwYXNzd2Q=\\\")"')
  local encoded = handle:read("*a")
  handle:close()
  
  -- Trim whitespace and newlines
  encoded = encoded:gsub('%s+$', '')
  
  -- Only set variable if we got valid output (not an error)
  if encoded and encoded ~= "" and not encoded:match("Error") then
    request.variables.set("authHeader_Local_JS_01", encoded)
  else
    print("Error getting encoded value: " .. (encoded or "nil"))
  end
%}
// Request (200)
GET https://httpbin.org/basic-auth/user/passwd
Authorization: Basic {{authHeader_Local_JS_01}}
###

Pseudo-JavaScript second example

# @lang=lua
< {%
  -- Use Lua to execute a Node.js command and capture its output
  local handle = io.popen('node -e "console.log(Buffer.from(\\\"user:passwd\\\").toString(\\\"base64\\\"))"')
  local encoded = handle:read("*a")
  handle:close()
  
  -- Trim whitespace and newlines
  encoded = encoded:gsub('%s+$', '')
  
  -- Only set variable if we got valid output (not an error)
  if encoded and encoded ~= "" and not encoded:match("Error") then
    request.variables.set("authHeader_Local_JS_02", encoded)
  else
    print("Error getting encoded value: " .. (encoded or "nil"))
  end
%}
// Request (200)
GET https://httpbin.org/basic-auth/user/passwd
Authorization: Basic {{authHeader_Local_JS_02}}
###