JC Version 1.7.1 Released | Brazil's Blog

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I’m happy to announce that jc version 1.7.1 has been released and is available on github and pypi. In addition to the new and updated parsers and features outlined below, some back-end code cleanup to improve performance along with minor bug fixes were completed.

To upgrade, run:

$ pip3 install --upgrade jc

New Parsers

jc now includes 37 parsers! New parsers (tested on linux and OSX) include id, crontab-u, INI, XML, and YAML:

id parser

Linux and OSX support for the id command:

$ id | jc --id -p
{
  "uid": {
    "id": 1000,
    "name": "joeuser"
  },
  "gid": {
    "id": 1000,
    "name": "joeuser"
  },
  "groups": [
    {
      "id": 1000,
      "name": "joeuser"
    },
    {
      "id": 10,
      "name": "wheel"
    }
  ],
  "context": {
    "user": "unconfined_u",
    "role": "unconfined_r",
    "type": "unconfined_t",
    "level": "s0-s0:c0.c1023"
  }
}

crontab files with user defined

Some crontab files contain the user field. In this case, use the new crontab-u parser:

$ cat /etc/crontab | jc --crontab-u -p
{
  "variables": [
    {
      "name": "MAILTO",
      "value": "root"
    },
    {
      "name": "PATH",
      "value": "/sbin:/bin:/usr/sbin:/usr/bin"
    },
    {
      "name": "SHELL",
      "value": "/bin/bash"
    }
  ],
  "schedule": [
    {
      "minute": [
        "5"
      ],
      "hour": [
        "10-11",
        "22"
      ],
      "day_of_month": [
        "*"
      ],
      "month": [
        "*"
      ],
      "day_of_week": [
        "*"
      ],
      "user": "root",
      "command": "/var/www/devdaily.com/bin/mk-new-links.php"
    },
    {
      "minute": [
        "30"
      ],
      "hour": [
        "4/2"
      ],
      "day_of_month": [
        "*"
      ],
      "month": [
        "*"
      ],
      "day_of_week": [
        "*"
      ],
      "user": "root",
      "command": "/var/www/devdaily.com/bin/create-all-backups.sh"
    },
    {
      "occurrence": "yearly",
      "user": "root",
      "command": "/home/maverick/bin/annual-maintenance"
    },
    {
      "occurrence": "reboot",
      "user": "root",
      "command": "/home/cleanup"
    },
    {
      "occurrence": "monthly",
      "user": "root",
      "command": "/home/maverick/bin/tape-backup"
    }
  ]
}

INI file parser

Convert generic INI files to JSON:

$ cat example.ini
[DEFAULT]
ServerAliveInterval = 45
Compression = yes
CompressionLevel = 9
ForwardX11 = yes

[bitbucket.org]
User = hg

[topsecret.server.com]
Port = 50022
ForwardX11 = no

$ cat example.ini | jc --ini -p
{
  "bitbucket.org": {
    "serveraliveinterval": "45",
    "compression": "yes",
    "compressionlevel": "9",
    "forwardx11": "yes",
    "user": "hg"
  },
  "topsecret.server.com": {
    "serveraliveinterval": "45",
    "compression": "yes",
    "compressionlevel": "9",
    "forwardx11": "no",
    "port": "50022"
  }
}

XML file parser

Convert generic XML files to JSON:

$ cat cd_catalog.xml 
<?xml version="1.0" encoding="UTF-8"?>
<CATALOG>
  <CD>
    <TITLE>Empire Burlesque</TITLE>
    <ARTIST>Bob Dylan</ARTIST>
    <COUNTRY>USA</COUNTRY>
    <COMPANY>Columbia</COMPANY>
    <PRICE>10.90</PRICE>
    <YEAR>1985</YEAR>
  </CD>
  <CD>
    <TITLE>Hide your heart</TITLE>
    <ARTIST>Bonnie Tyler</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>CBS Records</COMPANY>
    <PRICE>9.90</PRICE>
    <YEAR>1988</YEAR>
  </CD>
  ...

$ cat cd_catalog.xml | jc --xml -p
{
  "CATALOG": {
    "CD": [
      {
        "TITLE": "Empire Burlesque",
        "ARTIST": "Bob Dylan",
        "COUNTRY": "USA",
        "COMPANY": "Columbia",
        "PRICE": "10.90",
        "YEAR": "1985"
      },
      {
        "TITLE": "Hide your heart",
        "ARTIST": "Bonnie Tyler",
        "COUNTRY": "UK",
        "COMPANY": "CBS Records",
        "PRICE": "9.90",
        "YEAR": "1988"
      },
  ...
}

YAML file parser

Convert YAML files to JSON – even files that contain multiple YAML documents:

$ cat istio-mtls-permissive.yaml 
apiVersion: "authentication.istio.io/v1alpha1"
kind: "Policy"
metadata:
  name: "default"
  namespace: "default"
spec:
  peers:
  - mtls: {}
---
apiVersion: "networking.istio.io/v1alpha3"
kind: "DestinationRule"
metadata:
  name: "default"
  namespace: "default"
spec:
  host: "*.default.svc.cluster.local"
  trafficPolicy:
    tls:
      mode: ISTIO_MUTUAL

$ cat istio-mtls-permissive.yaml | jc --yaml -p
[
  {
    "apiVersion": "authentication.istio.io/v1alpha1",
    "kind": "Policy",
    "metadata": {
      "name": "default",
      "namespace": "default"
    },
    "spec": {
      "peers": [
        {
          "mtls": {}
        }
      ]
    }
  },
  {
    "apiVersion": "networking.istio.io/v1alpha3",
    "kind": "DestinationRule",
    "metadata": {
      "name": "default",
      "namespace": "default"
    },
    "spec": {
      "host": "*.default.svc.cluster.local",
      "trafficPolicy": {
        "tls": {
          "mode": "ISTIO_MUTUAL"
        }
      }
    }
  }
]

Updated Parsers

• history parser now outputs line fields as integers
• crontab parser bug fix for an issue that sometimes lost a row of data
• Updated the compatibility information for du and history parsers

__version__ Attribute Added

Python programmers can now call the __version__ attribute on all parsers when running them as modules.

>>> import jc.parsers.arp
>>> print(jc.parsers.arp.__version__)
1.1

Added Exit Codes

jc will now provide an exit code (1) if it did not successfully exit.

Schema Changes

The history parser now outputs line fields as integers

$ history | jc --history -p
[
  {
    "line": 118,
    "command": "sleep 100"
  },
  ...
]
 

Full Parser List

• arp
• crontab
• crontab-u
• df
• dig
• du
• env
• free
• fstab
• history
• hosts
• id
• ifconfig
• INI
• iptables
• jobs
• ls
• lsblk
• lsmod
• lsof
• mount
• netstat
• pip list
• pip show
• ps
• route
• ss
• stat
• systemctl
• systemctl list-jobs
• systemctl list-sockets
• systemctl list-unit-files
• uname -a
• uptime
• w
• XML
• YAML

For more information on the motivations for creating jc, see my blog post.

Happy parsing!