@deademx/dota2 is the Dota 2 (Source 2) demo parser and replay player for Node.js, Deno, Bun, and browsers, built on top of @deademx/engine.

The engine documentation covers the shared model — how to subscribe to data, use interceptors, configure the parser. This document covers Dota 2-specific details only.

Sibling packages: deadem (Deadlock) and @deademx/cs2 (Counter-Strike 2).

Contents

• Installation Install from npm or use the browser bundle.
• Quick Start Parse a replay, print stats.
• What Dota 2 Adds Everything the package registers on top of the engine.
  • Message Types Dota 2-specific message types.
  • String Tables Dota 2-specific string tables.
  • Decoders Dota 2-specific entity field decoders.
• Examples Runnable scripts: parsing, player.
• Compatibility Game patch and runtimes.
• Performance Measured throughput and memory usage.
• License MIT.

Installation

Node.js

npm install @deademx/dota2 --save

import { Parser, Player } from '@deademx/dota2';

Browser

<script src="//cdn.jsdelivr.net/npm/@deademx/[email protected]/dist/deadem-dota2.min.js"></script>

const { Parser, Player } = window.deademDota2;

Quick Start

import { createReadStream } from 'node:fs';

import { Parser, Printer } from '@deademx/dota2';

const parser = new Parser();
const readable = createReadStream('./match.dem');

await parser.parse(readable);

const printer = new Printer(parser);

printer.printStats();

await parser.dispose(); // cleanup state and resources

What Dota 2 Adds

Bootstrap registers the Dota 2 schema onto the engine registry:

Message Types

Dota 2-specific MessagePacketTypes — chat, objectives, economy.

String Tables

Dota 2-specific StringTableTypes.

| Table | Entries | Content | | --- | --- | --- | | StringTableType.ACTIVE_MODIFIERS | hundreds | Every buff/debuff on every entity. Decoded into CDOTAModifierBuffTableEntry lazily on first entry.value read. | | StringTableType.COMBAT_LOG_NAMES | hundreds | Resolves combat log entity/ability/item ids to names. | | StringTableType.COOLDOWN_NAMES | hundreds | Resolves ability cooldown ids to names. | | StringTableType.DOWNLOADABLES | hundreds | — | | StringTableType.ECON_ITEMS | hundreds | Equipped cosmetic items. | | StringTableType.LUA_MODIFIERS | hundreds | — | | StringTableType.MODIFIER_NAMES | thousands | Resolves ActiveModifiers.modifierClass to readable names. | | StringTableType.PARTICLE_ASSETS | hundreds | — | | StringTableType.RESPONSE_KEYS | hundreds | — |

Decoders

Dota 2-specific entity field decoders. Entity examples: CDOTAPlayerController, CDOTAGameRulesProxy. Entities, fields and types can be browsed in Deadem Explorer.

Examples

All example scripts live in the examples-node-dota2 package. They look for demo files in /demos; missing files are downloaded automatically from deadem.com.

Parsing

| # | Description | Source | Command | | --- | --- | --- | --- | | 100 | Parse a single replay file | 100_parse.js | node ./packages/examples-node-dota2/scripts/100_parse.js | | 101 | Parse multiple replay files | 101_parse_multiple.js | node ./packages/examples-node-dota2/scripts/101_parse_multiple.js --matches="8773493455,8777738576" | | 102 | Parse selected message types | 102_parse_selective.js | node ./packages/examples-node-dota2/scripts/102_parse_selective.js | | 103 | Print chat messages | 103_parse_chat.js | node ./packages/examples-node-dota2/scripts/103_parse_chat.js | | 104 | Rank high-churn entity classes and fields from ENTITY_PACKET deltas | 104_parse_entity_field_stats.js | node ./packages/examples-node-dota2/scripts/104_parse_entity_field_stats.js | | 105 | Print the combat log, names resolved through CombatLogNames | 105_parse_combat_log.js | node ./packages/examples-node-dota2/scripts/105_parse_combat_log.js | | 106 | Rank unit order fields by how often they are present and change | 106_parse_unit_orders.js | node ./packages/examples-node-dota2/scripts/106_parse_unit_orders.js |

Player

| # | Description | Source | Command | | --- | --- | --- | --- | | 200 | Load, seek, play, and pause a replay | 200_play.js | node ./packages/examples-node-dota2/scripts/200_play.js |

Compatibility

• Game patch: tested with Dota 2 demos from patch 7.41e and below.
• Runtimes: Node.js v18+, Deno, Bun; browsers: Chrome, Firefox, Safari, Edge.

Performance

| # | Configuration | Ticks/sec | 30-min replay, sec | Max Heap, MB | Max ArrayBuffers, MB | Max RSS, MB | | - | ------------------------------------------------------------------------------------- | ---------------- | ------------------ | ------------- | -------------------- | ------------ | | 1 | Everything — ParserConfiguration.DEFAULT | 25 464 +- 3.63% | ~2.12 | 104 +- 18.28% | 48 +- 28.16% | 330 +- 0.92% | | 2 | Chat — messagePacketTypes: [ DOTA_UM_CHAT_MESSAGE ] | 168 743 +- 3.21% | ~0.32 | 39 +- 6.07% | 22 +- 13.72% | 232 +- 6.87% | | 3 | One entity class — SVC_PACKET_ENTITIES + entityClasses: [ CDOTAPlayerController ] | 89 779 +- 0.75% | ~0.60 | 75 +- 23.59% | 17 +- 20.27% | 250 +- 2.96% |

Runtime: Node.js v22.14.0.

See engine performance notes for optimization tips.

License

MIT