L4D2 Bridge

This is an application and service layer to a L4D2 server, that allows for external events to influence an active server live.

Features

• Live server remote console
• Robust action handling
• Multiple service event ingesting
• Fairly lightweight
• History recall
• High flexibility with actions
• Configurable

Console Functionality

Anything typed in the text box will be sent directly to the server via RCON, with the following exceptions:

• reload - reloads the configuration of the application
• clear/cls - clears the console log entirely
• pause/unpause/resume - if the test service is running, will pause/unpause the test service from generating events
• cancel - cancel all current command events
• respawn - respawns all players
• action <actionname> <donor> - runs this action on the server
• commands - prints the number of events in the queue
• help - prints out these commands directly to the console

Influence Service Sources

• Tiltify Donations
• Twitch Events

Setup

Configuration

All configuration data is stored in a flat file called config.json. Upon first time running the application, a blank config.json file will be created for you. For the most part, these settings are fairly straight forward to fill out. The rest of the sections are explained below.

Actions

The actions section is a dictionary with key names that correspond to the RuleName or SuccessEvent of a matching rule definition (see Rules section), and the string array of server commands that should be ran when rules with the given keyname matches.

Acceptable server actions are:

    SpawnTank,
    SpawnSpitter,
    SpawnJockey,
    SpawnWitch,
    SpawnMob,
    SpawnMobSmall,
    SpawnMobMedium,
    SpawnMobLarge,
    SpawnBoomer,
    SpawnHunter,
    SpawnCharger,
    SpawnSmoker,
    Lootbox,
    SupplyCrate,
    HealAllPlayersSmall,
    HealAllPlayersLarge,
    HealAllPlayersRand,
    RespawnAllPlayers,
    UppiesPlayers,
    RandomPositive,
    RandomNegative,
    RandomSpecialInfected,
    Random

The Random server action does a coin flip and if heads, will run a RandomPositive action, if tails, a RandomNegative action will execute instead.

Example

Here is an example of some actions that are defined in a config file. Names such as "chaos" and "santa" are used in the rules.json later.

  "Actions": {
    "chaos": [
      "SpawnMobLarge",
      "RandomSpecialInfected",
      "SpawnCharger"
    ],
    "tank": [
      "SpawnTank"
    ],
    "lootbox": [
      "Lootbox"
    ],
    "santa": [
      "Lootbox",
      "Lootbox",
      "SupplyCrate"
    ]
  },

Mob Sizes

These are the ranges for each type of mob spawn size in the server commands list. The Rand setting is when the mob size is not provided (using SpawnMob).

Negative Weights

These are the weights for each of the negative-based Actions with their weightings from 1-100 on how often they should appear. These are used to calculate what affect is used when a rule with the action RandomNegative is executed. If a negative action is not specified, it will not be randomly chosen when RandomNegative is executed. This field is also used to determine RandomSepcialInfected roll spawn chances.

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Rules

rules.json is an MS RulesEngine formatted file.

The following important notes are:

• WorkflowName has to be one of the services that this application supports. Currently tiltify or twitch
• For each rule, either RuleName or SuccessEvent should be the name of one of the actions you have defined in the config.json file earlier. The system will check for RuleName matches first and upon failure to match, will check the SuccessEvent for an action match.
• All rules are evaluated for every event of a given service type. Execution does not stop on the first rule event, so you can have mutliple rules running at once.
• Rules run every time against a given source event.

Source Event Types

Rules can check their input object types against these values to determine actions. These are the types that are supported:

    Donation,
    Subscription,
    Resubscription,
    GiftSubscription,
    MultiGiftSubscription,
    Raid,
    ChatCommand

Source Event Data

All input objects are data objects that contain the following fields that can be checked against:

• Type - the Source Event Types listed above
• Name - The user that caused this event to fire
• Channel - The twitch channel this occurred on (tiltify does not pass this data)
• Amount - The numerical amount of whatever was passed.
• Message - Any messages attached (if supported)

Rules Extensions

The rules can take advantage of some added extensions to the processor to do string based checks. A class named REUtils is provided to the RulesEngine to help you with string processing.

• REUtils.HasValue - Returns a boolean if the given string has an actual value instead of null/whitespace
• REUtils.CheckContains - Given the input and a string of a value or csv of values, will check if the input contains any of the values in the check. All values will be projected to case-insensitive checks.
• REUtils.PercentChance - Given a whole number percentage chance, if the RNG flip is that percentage or lower, returns true

Example

[
  {
    "WorkflowName": "tiltify",
    "Rules": [
      {
        "RuleName": "tank",
        "RuleExpressionType": "LambdaExpression",
        "Expression": "input1.Type == EventType.Donation AND input1.Amount >= 5.00"
      },
      {
        "RuleName": "santa",
        "SuccessEvent": "nothing",
        "RuleExpressionType": "LambdaExpression",
        "Expression": "input1.Type == EventType.Donation AND REutils.CheckContains(input1.Message, \"help,santa,save\") == true AND input1.Amount > 1.00"
      },
      {
        "RuleName": "EveryCoolAndAwesomeRuleName",
        "SuccessEvent": "lootbox",
        "RuleExpressionType": "LambdaExpression",
        "Expression": "input1.Type == EventType.Donation"
      }
    ]
  }
]

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Server Dependencies

In addition to the modifications made in the L4D2Mods directory, the following additional plugins are needed.

• Left 4 DHooks Direct by Silvers.
• Weapon Handling by Lux.
• Survivor Utilities by Eärendil.
• Explosive Shots by Eärendil.
• multicolors by Bara, et all.