ridjohansen / structured-text-tools

A list of command line tools for manipulating structured text data

What follows is a list of text-based file formats with command line tools for manipulating each (with a focus on Linux).

Table of contents

• DSV
• XML, HTML
• JSON
• YAML, TOML
• INI
• Configuration files
• Bonus round: CLIs for single-file databases
• License
• Disclosure

DSV

Delimiter-separated values, including CSV, TSV, etc.

Awk

Awk is a POSIX-standard command line tool and programming language for processing DSV data. A list of Awk links follows.

• Awk.info — an extensive resource on Awk.
• AWK Vs NAWK Vs GAWK — a comparison of implementations.
• If you already know how to program in some language, the nawk man page is a great way to learn Awk quickly. What you learn from it will apply to other implementations on different platforms. Read it first if you feel overwhelmed by the sheer size of the GNU Awk manual.

POSIX commands

Name and link	Description
cut	Select portions of each line in a file or several. Can work with delimiter-separated fields. See man 1 cut on your system (GNU, FreeBSD).
join	Join the lines of two files on a common field. See man 1 join on your system (GNU, FreeBSD).
paste	Combine consecutive lines in a text file into one. See man 1 paste on your system (GNU, FreeBSD).
sort	Sort lines by key fields. See man 1 sort on your system (GNU, FreeBSD).
uniq	Find or remove repeated lines. See man 1 uniq on your system (GNU, FreeBSD).

Other tools

Name and link	Description
GNU datamash	Perform statistical operations on text input.
Miller	sed, awk, cut, join and sort for name-indexed data such as CSV and tabular JSON.
tab	A non-Turing-complete programming language for data processing. An alternative to Awk.
xsv	Index, slice, analyze, split and join CSV files.

SQL-based utilities

Name	Programming language and database engine	Features	Usage link	License
csvkit	Python, SQLite 3	Use header row for column names, custom input and output encoding, custom input field separator, custom output field separator, custom output formatting, CSV JOINs, Python module. Excel and JSON to CSV. CSV to JSON. SQL queries for CSV.	Usage	MIT
q	Python, SQLite 3	Use header row for column names, custom input and output encoding, gzipped input, custom input field separator (string literal), custom output field separator, custom output formatting, table JOINs, Python module.	Usage	GNU GPL 3
Sqawk	Tcl, SQLite 3	Use header row for column names, custom input field separator (regexp, per-file), custom input record delimiter (regexp, per-file), custom table names, custom output field separator, custom output record separator, merge selected columns into one, ASCII/Unicode table output, CSV input and output, JSON output, Tcl output, table JOINs.	Usage	MIT
sqawk	C, SQLite 3	Use header row for column names, column name aliases, can skip lines until a regexp matches, custom input field separator (string literal, per-file), keep SQLite file, show generated SQL, table JOINs.	Usage	?
Squawk	Python, custom SQL interpreter	Access log and CSV input, JSON and CSV output, Python code generation.	—	Three-clause BSD
termsql	Python, SQLite 3	Use header rows for column names, custom field separator (regexp), custom record separator (string literal), lines as columns, skip a given number of lines and the beginning and at the end, merge selected columns into one, HTML, CSV, SQL and Tcl output.	Manual	MIT
textql	Go, SQLite 3	Use header rows for column names, keep SQLite file, custom input field separator (string literal).	Usage	MIT

XML, HTML

Name and link	Description
pup	Filter HTML pages using CSS selectors. Inspired by jq.
Saxon	Scrape XML and HTML data using XPath. Documentation.
tq	Retrieve content from HTML using CSS selectors.
xml2	Convert XML and HTML to and from flat, greppable lists of "path=value" statements.
XMLStarlet	Transform, query, validate and edit XML documents.

See also: Grep and Sed Equivalent for XML Command Line Processing on StackOverflow.

JSON

Name and link	Description
jo	Create JSON objects from the shell.
jq	Create and manipulate JSON with a functional (as in "functional programming") DSL. Can convert JSON to other formats.
jshon	Create and manipulate JSON using getopt-style command-line options.
json2	Convert JSON to and from flat, greppable lists of "path=value" statements. Modeled after xml2.
jsonaxe	A JSON processor similar to JQ with a Python-based DSL.
json	Similar to JQ but written in JavaScript. Can run arbitrary JavaScript on the JSON input.
json-table	Transform JSON data structures into tables of columns and rows for processing in the shell.
json.tool (Python 3 docs)	Validate and pretty-print JSON data. This module is part of the standard library of Python 2/3 and so is likely available wherever Python is installed.
jsonwatch	Track changes in JSON data live from the command line. Works like watch -d.
lobar	Explore JSON interactively or process it in batch with a wrapper for lodash.chain(). An alternative to jq with a JavaScript syntax.
validjson	Validate or pretty-print JSON data.

YAML, TOML

With a format converter like Remarshal (below) you can use (JSON)[#json] tools to process YAML and TOML but beware that you don't lose data in the conversion (example).

Name and link	Description
Remarshal.	Convert between YAML, TOML and JSON. Validate or pretty-print each of the three formats.
shyaml	Read data from YAML files. Can output null-terminated strings for use in shell scripts.
validyaml	Validate or pretty-print YAML data.

INI

Name and link	Platform	License	Description
crudini	Any with Python 2.x	GNU GPLv2	Set and remove properties in INI files. Retrieve properties as shell script commands to set the corresponding variables. Outputs updated INI data or changes files in place.
IniFile (DOS version)	Windows (x86, x86-64), MS-DOS	Closed-source freeware	Set and remove properties in INI files. Retrieve properties as a list of batch file set commands to set the corresponding variables. Changes files in place.
initool	Windows, Linux, FreeBSD	MIT	Set and remove properties in INI files and check for their existence. Outputs updated INI data.

Configuration files

• Augeas — extract data from and modify a number of file formats. Note that not all formats are equally well supported by Augeas and for some only a limited subset of all valid files can be parsed.
• Elektra — manipulate configuration files. Shares Augeas' limitations when it comes to application-specific configuration files (it uses the same lenses) but has better support for generic formats such as JSON or INI.

Bonus round: CLIs for single-file databases

Name	Description	File format
GNU Recutils	"[A] set of tools and libraries to access human-editable, plain text databases called recfiles."	Text-based, roughly "key: value"
SDB	"[A] simple string key/value database based on djb's cdb disk storage and supports JSON and arrays introspection."	Binary
sqlite3(1)	"[A] simple command-line utility [...] that allows the user to manually enter and execute SQL statements against an SQLite database."	Binary

License

The contents of this document is licensed under the Creative Commons Attribution 4.0 International License. By contributing you agree to release your contribution under this license.

Disclosure

Sqawk, jsonwatch, Remarshal and initool were written by the curator of this document.