# @ts-graphviz/ast
> Graphviz AST(Abstract Syntax Tree) Utilities
Latest version **3.0.6** (published 2026-02-07) · MIT license · 2.1M weekly downloads
## Install
```sh
npm install @ts-graphviz/ast
pnpm add @ts-graphviz/ast
yarn add @ts-graphviz/ast
bun add @ts-graphviz/ast
```
## Health
**Score 80/100 (A)** — status: stable.
Positive: high downloads; has types; esm support; no vulnerabilities; has provenance.
## Facts
| | |
|---|---|
| Version | 3.0.6 |
| Published | 2026-02-07 |
| First published | 2024-02-25 |
| Weekly downloads | 2.1M |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM |
| Node | >=20 |
| Dependencies | 1 |
| Unpacked size | 192.7 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 203 |
| Author | kamiazya |
| Maintainers | kamiazya |
## Links
- npm: https://www.npmjs.com/package/@ts-graphviz/ast
- Repository: https://github.com/ts-graphviz/ts-graphviz
- Homepage: https://github.com/ts-graphviz/ts-graphviz#readme
- Issues: https://github.com/ts-graphviz/ts-graphviz/issues
- Funding: https://github.com/sponsors/ts-graphviz
- npm.io page: https://npm.io/package/@ts-graphviz/ast
## Dependencies (1)
- [@ts-graphviz/common](https://npm.io/package/@ts-graphviz/common.md) ^3.0.5
## Recent versions
- 3.0.6 (latest) — 2026-02-07
- 3.0.6-next-8edec5962ac368d759a4903f69e8db2cd0496c97 (next) — 2026-02-07
- 0.0.0-pr956-20240225163634 (develop) — 2024-02-25
- 3.0.6-next-0bbfc4b9b75a148a7befa38de56e708c6b50e534 — 2026-02-07
- 3.0.6-next-19f6894843460029b772f865e1571b6d3cca9a02 — 2026-01-04
- 3.0.6-next-7bb47523bbe841fed9235a9731cc8a1a3d7daf02 — 2025-12-02
- 3.0.6-next-cf506102146d4141e9d6b82af57210dda2ec8573 — 2025-11-12
- 3.0.6-next-984b47df8049ab0ec23269df464c7b7bbdeb9525 — 2025-11-11
- 3.0.5 — 2025-11-10
- 3.0.5-next-67a316f1e0eac9561c00d9257b6777a079848834 — 2025-11-10
- 3.0.5-next-9296372cefd7dcf81ff8d3d827bb124ac56849ec — 2025-11-10
- 3.0.5-next-4296b4e0cf17f36cc385c2ce93ec7ec89bd4a73a — 2025-10-26
- 3.0.5-next-11f7126347816f64f7892c8608b5e3bf1a826670 — 2025-10-26
- 3.0.5-next-dc3ef34316f5642c416711cb6a50704dbef7bb64 — 2025-10-26
- 3.0.4 — 2025-10-25
- … 73 more at https://npm.io/package/@ts-graphviz/ast/versions
## README
[](https://github.com/ts-graphviz/ts-graphviz/actions/workflows/main.yaml)
[](https://github.com/ts-graphviz/ts-graphviz/actions/workflows/codeql-analysis.yml)
[](https://github.com/ts-graphviz/ts-graphviz/blob/main/LICENSE)
[](#contributors-)
[](https://www.bestpractices.dev/projects/8396)
[](https://scorecard.dev/viewer/?uri=github.com/ts-graphviz/ts-graphviz)
[](https://tidelift.com/subscription/pkg/npm-ts-graphviz?utm_source=npm-ts-graphviz&utm_medium=readme)
[](https://badge.fury.io/js/ts-graphviz)
[](https://github.com/denoland/deno)
[](https://npmtrends.com/ts-graphviz)
# @ts-graphviz/ast
This package contains the module for processing the DOT language at the **A**bstract **S**yntax **T**ree (AST) level for the ts-graphviz library.
🔗
[](https://github.com/ts-graphviz/ts-graphviz)
[](https://www.npmjs.com/package/ts-graphviz)
[](https://ts-graphviz.github.io/ts-graphviz/)
[](https://deepwiki.com/ts-graphviz/ts-graphviz)
[](https://github.com/sponsors/ts-graphviz)
[](https://opencollective.com/ts-graphviz)
[](https://biomejs.dev/)
[](https://vitest.dev/)
[](https://rollupjs.org/)
---
> It is part of the ts-graphviz library, which is split into modular packages to improve maintainability, flexibility, and ease of use.
## Overview
This package is a foundational component of the ts-graphviz library that enables low-level manipulation of DOT language structures.
It provides a parser that converts DOT language strings into AST nodes and a stringifier that converts AST nodes back to DOT language.
## Main Functions
The AST package provides several key functions:
- `parse(input: string, options?)`: Parses a DOT language string into an AST structure
- `stringify(ast: ASTNode)`: Converts an AST structure to a DOT language string
- `fromModel(model)`: Converts a Graph Model to an AST structure
- `toModel(ast)`: Converts an AST structure to a Graph Model
## Usage Examples
### Parsing DOT Language
```ts
import { parse } from "@ts-graphviz/ast";
const dotString = "digraph G { A -> B; }";
const ast = parse(dotString);
console.log(ast);
// Output: A DotASTNode representing the DOT structure
```
#### Parser Options
The `parse` function accepts an optional second argument for configuration:
```ts
import { parse } from "@ts-graphviz/ast";
// Parse with custom security limits
const ast = parse(dotString, {
startRule: 'Dot', // Specify the starting rule (default: 'Dot')
maxHtmlNestingDepth: 200, // Maximum HTML nesting depth (default: 100)
maxEdgeChainDepth: 2000, // Maximum edge chain depth (default: 1000)
maxInputSize: 20971520, // Maximum input size in bytes (default: 10MB)
maxASTNodes: 200000 // Maximum AST nodes (default: 100,000)
});
```
**Available Options**:
| Option | Default | Description |
|--------|---------|-------------|
| `startRule` | `'Dot'` | Starting grammar rule for parsing |
| `maxHtmlNestingDepth` | `100` | Maximum depth of nested HTML-like structures |
| `maxEdgeChainDepth` | `1000` | Maximum depth of chained edges (e.g., `a -> b -> c -> ...`) |
| `maxInputSize` | `10485760` (10MB) | Maximum input size in bytes |
| `maxASTNodes` | `100000` | Maximum number of AST nodes to create |
**Security Note**:
These limits protect against denial-of-service attacks:
- **`maxHtmlNestingDepth`**: Prevents stack overflow from deeply nested HTML-like structures
- Normal use cases: typically <10 levels
- HTML-like labels are GraphViz DOT syntax, not browser HTML
- **`maxEdgeChainDepth`**: Prevents stack overflow from deeply chained edges
- Example dangerous input: `a -> b -> c -> ... -> z (1000+ nodes)`
- **`maxInputSize`**: Prevents memory exhaustion from extremely large files
- Default 10MB is sufficient for most legitimate graphs
- Can be increased for known large graphs or disabled with `0` (not recommended for untrusted input)
- **`maxASTNodes`**: Prevents memory exhaustion from inputs with excessive elements
- Each DOT element creates multiple AST nodes
- Example: A single node statement (`node1;`) creates ~2-3 AST nodes
- Can be disabled with `0` (not recommended for untrusted input)
**Important**: When processing untrusted DOT files (e.g., user uploads), keep these limits enabled with conservative values appropriate for your environment. For additional validation of untrusted content, see the validation guide in [@ts-graphviz/adapter documentation](../adapter/README.md#security-considerations).
### Generating DOT Language
```ts
import { parse, stringify } from "@ts-graphviz/ast";
const dotString = "digraph G { A -> B; }";
const ast = parse(dotString);
// Modify the AST if needed
const outputDotString = stringify(ast);
console.log(outputDotString);
// Output: "digraph G { A -> B; }"
```
## Error Handling
The package provides a specialized error class for handling syntax errors during parsing.
When a parsing error occurs, the parser throws a `DotSyntaxError` with detailed information about the issue, which helps in debugging DOT language syntax problems.
## Contributors 👥
Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/docs/en/emoji-key)):
This project follows the [all-contributors](https://github.com/all-contributors/all-contributors)
specification. Contributions of any kind welcome!
## Changelog 📜
See [CHANGELOG.md](https://github.com/ts-graphviz/ts-graphviz/blob/main/packages/ast/CHANGELOG.md) for more details.
## License ⚖️
This software is released under the MIT License, see [LICENSE](https://github.com/ts-graphviz/ts-graphviz/blob/main/LICENSE).
---
_Source: https://npm.io/package/@ts-graphviz/ast · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._
