Roblox API Dump

An API dump file is created when a Roblox executable is run using the following options:

RobloxPlayer -API api.txt
RobloxPlayerBeta --API api.txt

These dump the API to a file named api.txt. Note that Studio does not currently support this command. However, the ReflectionMetadata.xml file is required to generate the dump (otherwise a parsing error is reported), but is currently only distributed with studio and needs to be copied to RobloxPlayerBeta.exe's folder.

This repo contains Lua functions for parsing the contents of the dump into a Lua table, so that it may be manipulated more easily.

The first function, ParseAPI, uses regular expressions for parsing. It is small and fast, but will crash and burn if the contents of the dump are malformed. It is pretty much safe to use on an unmodified dump file taken directly from the Roblox exe.

In comparison, the second function, LexAPI, is larger and slower, but significantly more accurate. If the dump is malformed in any way, this function will tell you the exact location of the error, down to the character. Use this if you're making modifications to the dump file, and need to verify that it is correct.

Usage

Both functions expect a string, which is the contents of the dump file. They both return a table containing the parsed data, in the exact same format. Here's an example:

local ParseAPI = require 'ParseAPI'

local f = io.open('api.txt')
local data = f:read('*a')
f:close()

local database = ParseAPI(data)

Table Contents

The returned table is a list of "items", which are tables. All items contain the following fields:

• string type: The type of item. Used to indicate what other fields are available in the item.
• table tags: A set of tags attached to the item. Each entry is a ["tagname"]=true pair.

Each item has a specific type with its own additional fields:

• Class
  • string Name: The name of the class.
  • string Superclass: The class this class inherits from. Will be nil if the class does not inherit.
• Property
  • string Name: The name of the member.
  • string Class : The class this item is a member of.
  • string ValueType: The type of the property's value.
• Function
  • string Name: The name of the member.
  • string Class: The class this item is a member of.
  • string ReturnType: The type of the value returned by the function.
  • table Arguments: A list of arguments passed to the function. Each argument is a table containing the following fields:
    • string Name: The name of the argument.
    • string Type: The value type of the argument.
    • string Default: The default value if the argument is not given. Will be nil if the argument does not have default value.
• Event
  • string Name: The name of the member.
  • string Class: The class this item is a member of.
  • table Parameters: A list of parameters received by the event listener. Each parameter is a table containing the following fields:
    • string Name: The name of the parameter.
    • string Type: The value type of the parameter.
• Callback
  • string Name: The name of the member.
  • string Class: The class this item is a member of.
  • string ReturnType: The type of the value that should be returned by the callback.
  • table Parameters: A list of parameters received by the callback. Each parameter is a table containing the following fields:
    • string Name: The name of the parameter.
    • string Type: The value type of the parameter.
• YieldFunction
  • string Name: The name of the member.
  • string Class: The class this item is a member of.
  • string ReturnType: The type of the value returned by the function.
  • table Arguments: A list of arguments passed to the function. Each argument is a table containing the following fields:
    • string Name: The name of the argument.
    • string Type: The value type of the argument.
    • string Default: The default value if the argument is not given. Will be nil if the argument does not have default value.
• Enum
  • string Name: The name of the enum.
• EnumItem
  • string Enum: The enum this item is a member of.
  • string Name: The name associated with the enum item.
  • int Value: The enum item's integer value.

Example

Dump:

Class Instance : Root
	Property int Instance.DataCost [readonly] [RobloxPlaceSecurity]
	Function Instance Instance:FindFirstChild(string name, bool recursive = false)

Table:

return {
	{
		type = "Class";
		tags = {};
		Name = "Instance";
		Superclass = "Root";
	};
	{
		type = "Property";
		tags = {readonly = true, RobloxPlaceSecurity = true};
		Name = "DataCost";
		Class = "Instance";
		ValueType = "int";
	};
	{
		type = "Function";
		tags = {};
		Name = "FindFirstChild";
		Class = "Instance";
		ReturnType = "Instance";
		Arguments = {
			{
				Name = "name";
				Type = "string";
			};
			{
				Name = "recursive";
				Type = "bool";
				Default = "false";
			};
		};
	};
}