jc: JSON Convert CLI Tool and Python Library

1.25.6 · active · verified Wed Apr 15

jc is a CLI tool and Python library that converts the output of popular command-line tools and file-types to JSON, YAML, or Python dictionaries. This allows for easier parsing in scripts and seamless integration with tools like `jq`. The library is actively maintained with frequent releases, typically on a monthly or bi-monthly cadence.

Warnings

breaking The `iso-datetime` parser was removed. Use `datetime-iso` instead.
Fix: Replace `jc.parse('iso-datetime', ...)` with `jc.parse('datetime-iso', ...)`.
gotcha The `size` fields in `df` and `free` parsers were changed to integers and normalized to bytes, regardless of whether human-readable output (`-h`) was used in the original command. Previously, they might have been strings with units.
Fix: Update scripts that expect `size` as a string or in specific units to handle the new integer (byte) format. Perform explicit unit conversion if human-readable output is desired.
gotcha Attempting to use parsers that rely on optional third-party libraries (e.g., `xmltodict` for XML parsing) without those libraries installed will result in an `ImportError` or a crash.
Fix: Ensure all necessary optional dependencies are installed via `pip install jc[xml]` (if extras are defined) or `pip install <dependency_name>` if you plan to use parsers requiring them. For `xmltodict`, install with `pip install xmltodict`.
gotcha The `--slurp` functionality (or `slurp=True` in `jc.parse()`) only works with parsers designed for single-line inputs, not with streaming parsers. Using it with unsupported parsers will not yield the expected results.
Fix: Check `jc -hhh` on the command line or refer to the documentation to identify parsers compatible with the `--slurp` option before using it.

Install

pip install jc Install jc

Imports

jc
```
import jc
```
Most common and recommended way to access the high-level parsing API.
jc.parsers.<parser_name>
```
import jc.parsers.dig
```
For directly importing specific parser modules, bypassing the high-level API.

Quickstart

This quickstart demonstrates how to use `jc` to parse the output of a command-line tool. It captures command output using `subprocess.check_output` and then uses `jc.parse()` with the appropriate parser name ('dig', 'df') to convert it into a Python dictionary or list of dictionaries.

import subprocess
import jc

# Example: Parse 'dig example.com' output
cmd_output = subprocess.check_output(['dig', 'example.com'], text=True)
data = jc.parse('dig', cmd_output)

# The result is a Python list of dictionaries
print(data[0]['answer'])

# Example: Parse 'df' output
df_output = subprocess.check_output(['df', '-h'], text=True)
df_data = jc.parse('df', df_output)
print(df_data[0]['filesystem'])

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