CLI

CLI Reference

The typediagram CLI reads typeDiagram source (or other language source) and writes SVG or language code to stdout.

Installation

npm install -g typediagram
# or use via npx:
npx typediagram schema.td > diagram.svg

Usage

typediagram [options] [file]

If file is omitted, reads from stdin. Output goes to stdout. Errors go to stderr with exit code 1.

Options

Flag Value Description
--from typescript|python|rust|go|csharp|fsharp|dart|protobuf|php Convert from language source to SVG
--to typescript|python|rust|go|csharp|fsharp|dart|protobuf|php Convert from typeDiagram to language source
--theme light|dark Color theme (default: light)
--font-size number Font size in pixels
-h, --help Show help

--from and --to are mutually exclusive.

Examples

Render typeDiagram to SVG

# From a file
typediagram schema.td > diagram.svg

# From stdin
echo 'type User { name: String }' | typediagram > diagram.svg

# Dark theme
typediagram --theme dark schema.td > diagram.svg

# Custom font size
typediagram --font-size 16 schema.td > diagram.svg

Convert from other languages

# TypeScript interfaces → SVG
typediagram --from typescript types.ts > diagram.svg

# Python dataclasses → SVG
typediagram --from python models.py > diagram.svg

# Rust structs/enums → SVG
typediagram --from rust types.rs > diagram.svg

# Go structs → SVG
typediagram --from go types.go > diagram.svg

# C# classes → SVG
typediagram --from csharp Models.cs > diagram.svg

Export to other languages

# typeDiagram → TypeScript
typediagram --to typescript schema.td > types.ts

# typeDiagram → Python
typediagram --to python schema.td > models.py

# typeDiagram → Rust
typediagram --to rust schema.td > types.rs

# typeDiagram → Go
typediagram --to go schema.td > types.go

# typeDiagram → C#
typediagram --to csharp schema.td > Models.cs

Exit codes

Code Meaning
0 Success
1 Parse error, render error, unknown type in --to, or bad args

Parse errors include line:col diagnostics on stderr:

  3:12  error   expected '{', got Ident "User"
  7:1   error   unexpected token EOF

Unknown types fail --to

Code generation is strict: every referenced type must be a primitive, a generic built-in (List, Map, Option, Any), a declared type, or a generic parameter. An unknown name (a typo, or an unsupported type) exits 1 with a diagnostic instead of emitting source that won't compile:

$ printf 'type Probe {\n  a: Timestamp\n}\n' | typediagram --to python
  0:0  error   unknown type 'Timestamp': not a primitive, builtin, or declared type — declare it or use a builtin scalar
$ echo $?
1

Use the built-in semantic scalars DateTime, Uuid, and Decimal for timestamps, ids, and money — they map to each language's native type. Rendering a diagram (without --to) still treats unknown names as opaque external references.

Makefile shortcuts

make cli FILE=schema.td                    # typeDiagram → SVG
make cli FILE=types.ts LANG=typescript     # TypeScript → SVG
make cli FILE=models.py LANG=python        # Python → SVG