Extensible data structure traversal in the command line
Project description
lens
lens
is a command line tool for easy traversal and
pretty printing fo data structures from the terminal.
It is extensible.
Uses the great Pygments library.
It should work on both Python 2 and 3, but was developed with Python 3 in mind.
Installation
The package is yet registered to PyPI. That means you should
be able to install it with pip. lens
was already taken, so
we used lens-cli
.
pip install lens-cli
Usage
Calling lens -h
will print this message:
usage: lens [-h] [--input INPUT] [--format FORMAT]
[--no-highlight NO_HIGHLIGHT]
[key [key ...]]
Extensible data structure traversal from the command line
positional arguments:
key the keys to traverse
optional arguments:
-h, --help show this help message and exit
--input INPUT, -i INPUT
the input file (defaults to the standard input)
--format FORMAT, -f FORMAT
the data format to consume (defaults to json)
--no-highlight NO_HIGHLIGHT, -n NO_HIGHLIGHT
prevent syntax highlighting
This should be relatively straightforward. Let's go through a few examples:
# just calling lens will print everything, syntax-highlighted
$ curl -s https://httpbin.org/get | lens
{
"args": {},
"headers": {
"Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",
"Accept-Encoding": "gzip, deflate, br",
"Accept-Language": "de,en-US;q=0.7,en;q=0.3",
"Dnt": "1",
"Host": "httpbin.org",
"Referer": "https://httpbin.org/",
"Upgrade-Insecure-Requests": "1",
"User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:50.0) Gecko/20100101 Firefox/50.0"
},
"origin": "213.61.134.12",
"url": "https://httpbin.org/get"
}
# suppose we only want to see the "Host" header
$ curl -s https://httpbin.org/get | lens header Host
"httpbin.org"
# or use xml
$ curl -s https://httpbin.org/xml | lens -f=xml
<slideshow
title="Sample Slide Show"
date="Date of publication"
author="Yours Truly"
>
<slide type="all">
<title>Wake up to WonderWidgets!</title>
</slide>
<slide type="all">
<title>Overview</title>
<item>Why <em>WonderWidgets</em> are great</item>
<item/>
<item>Who <em>buys</em> WonderWidgets</item>
</slide>
</slideshow>
# suppose we want to only get the title of the second slide
$ curl -s https://httpbin.org/xml | lens -f=xml slide 1 title
<title>Overview</title>
We can also read from files by providing an -i
option.
lens also discovers if its output is redirected to a file, in which case
no syntax highlighting will be applied (the same can be achieved through
the --no-highlighting/-n
option).
Extending
You can write your own parsers/traversers - admittedly, parsers is not a great name, but for now we stick with it.
They should inherit from LensParser
in lens.parsers.base
,
and at least implement the method treat(self, inpt, keys)
,
where inpt
is the input string and keys
are the keys to
traverse. It should return the traversed data structure as a
string.
Optionally, the parser can specify a Pygments lexer by exposing
the static attribute lexer
, if highlighting is applicable. It
will work without one, though.
The plugins can be third party pip
modules, in which case they
should follow the naming scheme lens-{format-name}
and export
the parser under the name Parser
.
An example of a plugin can be found in the bson parser repository.
That is all you need to know!
Have fun!
Project details
Download files
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.
Source Distribution
File details
Details for the file lens-cli-0.1.4.tar.gz
.
File metadata
- Download URL: lens-cli-0.1.4.tar.gz
- Upload date:
- Size: 5.0 kB
- Tags: Source
- Uploaded using Trusted Publishing? No
- Uploaded via: twine/1.12.1 pkginfo/1.4.2 requests/2.21.0 setuptools/41.0.1 requests-toolbelt/0.8.0 tqdm/4.24.0 CPython/3.7.4
File hashes
Algorithm | Hash digest | |
---|---|---|
SHA256 | 8a755ceb5a07044b4dabbd1cb18bbc17a207338f25d7b46b9082a827eca3392a |
|
MD5 | 67fdc11aba9ca83f9ca1b45511301ab5 |
|
BLAKE2b-256 | fd59cc0fb74e66366f31b0543764da59a07d048866585b42ea02f77f728918b7 |