Writing this Plugin (Python)

Entry Point

Plugins use start_plugin_with_fn with a function that receives PluginInput and returns PluginOutput:

from cyanprintsdk import start_plugin_with_fn, PluginInput, PluginOutput

def plugin_fn(input: PluginInput) -> PluginOutput:
    # Plugin logic here
    return PluginOutput(directory=input.directory)

start_plugin_with_fn(plugin_fn)

PluginInput

class PluginInput:
    directory: str   # Absolute path to the generated output directory
    config: Any      # Configuration from template's cyan.yaml

Important: PluginInput has NO SDK file helpers. There are no read_dir, read_file, or file_exists methods. Plugins use native OS operations for all file I/O.

PluginOutput

class PluginOutput:
    directory: str   # Return the directory path (typically input.directory)

Native File I/O Patterns

from pathlib import Path

dir = Path(input.directory)

# Read a file
content = (dir / 'src' / 'main.py').read_text()

# Check if file exists
exists = (dir / 'README.md').exists()

# List directory
files = list((dir / 'src').iterdir())

# Write a file
(dir / 'src' / 'main.py').write_text(modified)

Command Execution Patterns

import subprocess

result = subprocess.run(
    ["prettier", "--write", "."],
    cwd=input.directory,
    capture_output=True,
    text=True,
    check=True,
)

File Mutation Workflow

Read files from input.directory, modify content, write back:

from pathlib import Path

file_path = Path(input.directory) / 'src' / 'main.py'
content = file_path.read_text()
modified = content.replace('old', 'new')
file_path.write_text(modified)

Entry Point Skeleton

from cyanprintsdk import start_plugin_with_fn, PluginInput, PluginOutput
from pathlib import Path
import subprocess

def plugin_fn(input: PluginInput) -> PluginOutput:
    dir = Path(input.directory)
    config = input.config

    # Use pathlib / open() for file I/O
    # Use subprocess.run for command execution

    return PluginOutput(directory=input.directory)

start_plugin_with_fn(plugin_fn)

Advanced Patterns

Walk directory recursively

from pathlib import Path

all_files = list(Path(input.directory).rglob("*"))
py_files = list(Path(input.directory).rglob("*.py"))

Read, modify, and write a file

from pathlib import Path

file_path = Path(input.directory) / "src" / "main.py"
content = file_path.read_text()
modified = content.replace("print(", "logger.info(")
file_path.write_text(modified)