hosh-shell.github.io

Hosh

Features

Hosh is an experimental shell, featuring:

portability¹
- written in Java 11, distributed as Uber-JAR
- works out-of-the-box in Windows, MacOS, Linux
- limited HTTP 1.1/2.0 client (http) and ifconfig clone (network) as built-in commands
usability as first class citizen²
- interactive output displayed as table by default
- sorting with natural sort
- ANSI colors by default
- errors (i.e. stderr) always colored in red
- file sizes reported by default as KB, MB, GB, …
- better history by default
  - record timestamps for each command (see history command)
  - ignoring duplicated by default (like HISTCONTROL=ignoredups in bash)
  - append to history is incremental and shared between all sessions
  - no limits
robust scripts by default
- as if running bash scripts with set -euo pipefail (unofficial-strict-mode)
- strongly typed (but not statically typed)
  - every value has a type not everything is a string
  - avoiding the need to dump/parse fields
  - basic types are: text, number, path, duration and instant
pipelines built around schema-less records:
- built-in commands produce records with well-defined keys
- use | schema to inspect available keys
- interoperability with external commands is achieved by using single-key record (with key text)
wrapping commands, with before/after behavior:
- withTime { lines very-big-file.txt | count } like time command in bash
- withLock file.lock { command } run command as critical section guarded by file.lock
- benchmark 10 { command } run command 10 times and then report best/worst/average execution time
built with modern tooling and concepts
- designed to be compatible with Java Platform Module System (i.e. Jigsaw)
- designed to be compatible with Project Loom as commands run in isolated thread and communicate only via immutable messages
- Fitness Functions from Evolutionary Architecture ISBN-13: 978-1491986363)

¹ it is not intended to conform to IEEE POSIX P1003.2/ISO 9945.2 Shell and Tools standard

² much more design and work is needed in this area

Downloads

Binary releases:

v0.2.0 - 2023-12-31 [with GPG signature]

Getting started

Requirements: JDK17+

$ java -jar hosh-0.2.0.jar
hosh> echo "hello world!"
hello world!
hosh>

Examples

Sorting

Sorting is always performed using a well-defined key:

hosh> ls
# unsorted, following local file-system order
...
hosh> ls | schema
path size
hosh> ls | sort size
# files sorted by size
...
hosh> ls | sort path
# files sorted by alphanum algorithm
...

Find top-n files by size

Walk is able to recursively walk a directory and its subdirectories, providing file name and size:

hosh> walk . | schema
path size
...

By sorting the output of walk it is trivial to detect the biggest files:

hosh> walk . | sort size desc | take 5
aaa 2,5MB
bbb 1MB
ccc 1MB
ddd 1MB
eee 1MB

HTTP

Stream line by line a TSV file via HTTPS, take first 10 lines, split each line by tab yielding a 1-indexed record and finally show a subset of keys.

Bash + wget + awk:

bash$ wget -q -O - -- https://git.io/v9MjZ | head -n 10 | awk -v OFS='\t' '{print $10, $1, $12}'

Hosh (no external commands):

hosh> http https://git.io/v9MjZ | take 10 | split text '\\t' | select 10 1 12

Glob expansion and lambda blocks

To recursively remove all .class files in target:

hosh> walk target/ | glob '*.class' | { path -> rm ${path}; echo removed ${path} }

{ path -> ... } is lambda syntax, inside this scope is possible to use ${path}.

Parsing

It is possible to create records by using regex built-in with capturing groups:

hosh> git config -l | schema
text
...
hosh> git config -l | regex text '(?<key>.+)=(?<value>.+)' | take 2
key                value
credential.helper  osxkeychain
user.name          Davide Angelocola
hosh> hosh> git config -l | regex text '(?<key>.+)=(?<value>.+)' | take 2 | schema
key value
key value