cheat/README.md
Chris Lane ce37b670c7 feat(installer): implement "installer"
Squashed commit of the following:

commit 5c322e79b7
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Fri Mar 6 19:56:56 2020 -0500

    docs(README): update the `README`

    Update the `README` to document the improved config-generation
    mechanism.

commit 803e1f014c
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Fri Mar 6 19:19:49 2020 -0500

    feat(config-init): platform-specific pathing

    Update `--init` subcommand to rely upon the same platform-detection
    intelligence that was previously implemented by the "installer".

    The installer and `--init` should now produce identical config files.

commit 99c48097e2
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Fri Mar 6 18:26:33 2020 -0500

    feat(installer): platform-correct config templating

    Modify the "installer" to populate cheatpaths with sensible defaults
    based on the detection of the user's operating system and environment.

commit 8e1580ff5a
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Thu Mar 5 20:19:58 2020 -0500

    fix(tests): fix `config.Paths` tests

    Refactor `config.Paths` (by externalizing a call to `homedir.Dir`) to
    decouple it from filesystem paths, thus facilitating cleaner unit-tests.

commit a08dca70d9
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Thu Mar 5 18:14:27 2020 -0500

    feat(installer): default path selection

    Modify the installer to improve default config and cheatsheet path
    selection.

commit e15bc6c966
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Thu Mar 5 17:49:50 2020 -0500

    fix(typo): correct comment typo in `main.go`

commit efd09575df
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Thu Mar 5 17:46:49 2020 -0500

    feat(config): refactor config path detection

    Previously, failing other checks, on Unix and BSD systems,
    `config.Paths` would attempt to compute the user's home directory by
    reading the `HOME` environment variable.

    This change deprecates that approach with a call to `homedir.Dir`, which
    is used elsewhere throughout the application.

commit ec10244ebe
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Thu Mar 5 17:15:28 2020 -0500

    chore(installer): delete unused file

    Delete `installer/installer.go`, which (in hindsight) was unnecessary.

commit ebd9ec6287
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Wed Mar 4 19:31:13 2020 -0500

    wip(installer): stub experimental "installer"

    Stubs out an experimental "installer" that will help new users to
    quickly configure `cheat`.

commit ecac5a0971
Author: Chris Lane <chris@chris-allen-lane.com>
Date:   Wed Mar 4 19:30:12 2020 -0500

    chore(dependencies): updates vendored dependencies
2020-03-06 20:17:26 -05:00

5.7 KiB

cheat

Build Status

cheat allows you to create and view interactive cheatsheets on the command-line. It was designed to help remind *nix system administrators of options for commands that they use frequently, but not frequently enough to remember.

The obligatory xkcd

Use cheat with cheatsheets.

Example

The next time you're forced to disarm a nuclear weapon without consulting Google, you may run:

cheat tar

You will be presented with a cheatsheet resembling the following:

# To extract an uncompressed archive:
tar -xvf '/path/to/foo.tar'

# To extract a .gz archive:
tar -xzvf '/path/to/foo.tgz'

# To create a .gz archive:
tar -czvf '/path/to/foo.tgz' '/path/to/foo/'

# To extract a .bz2 archive:
tar -xjvf '/path/to/foo.tgz'

# To create a .bz2 archive:
tar -cjvf '/path/to/foo.tgz' '/path/to/foo/'

Installing

cheat has no dependencies. To install it, download the executable from the releases page and place it on your PATH.

Configuring

conf.yml

cheat is configured by a YAML file that will be auto-generated on first run. Should you need to create a config file manually, you can do so via:

mkdir -p ~/.config/cheat && cheat --init > ~/.config/cheat/conf.yml

By default, the config file is assumed to exist on an XDG-compliant configuration path like ~/.config/cheat/conf.yml. If you would like to store it elsewhere, you may export a CHEAT_CONFIG_PATH environment variable that specifies its path:

export CHEAT_CONFIG_PATH="~/.dotfiles/cheat/conf.yml"

Cheatsheets

Cheatsheets are plain-text files with no file extension, and are named according to the command used to view them:

cheat tar     # file is named "tar"
cheat foo/bar # file is named "bar", in a "foo" subdirectory

Cheatsheet text may optionally be preceeded by a YAML frontmatter header that assigns tags and specifies syntax:

---
syntax: javascript
tags: [ array, map ]
---
// To map over an array:
const squares = [1, 2, 3, 4].map(x => x * x);

The cheat executable includes no cheatsheets, but community-sourced cheatsheets are available. You will be asked if you would like to install the community-sourced cheatsheets the first time you run cheat.

Cheatpaths

Cheatsheets are stored on "cheatpaths", which are directories that contain cheetsheets. Cheatpaths are specified in the conf.yml file.

It can be useful to configure cheat against multiple cheatpaths. A common pattern is to store cheatsheets from multiple repositories on individual cheatpaths:

# conf.yml:
# ...
cheatpaths:
  - name: community                   # a name for the cheatpath
    path: ~/documents/cheat/community # the path's location on the filesystem
    tags: [ community ]               # these tags will be applied to all sheets on the path
    readonly: true                    # if true, `cheat` will not create new cheatsheets here

  - name: personal
    path: ~/documents/cheat/personal  # this is a separate directory and repository than above
    tags: [ personal ]
    readonly: false                   # new sheets may be written here
# ...

The readonly option instructs cheat not to edit (or create) any cheatsheets on the path. This is useful to prevent merge-conflicts from arising on upstream cheatsheet repositories.

If a user attempts to edit a cheatsheet on a read-only cheatpath, cheat will transparently copy that sheet to a writeable directory before opening it for editing.

Directory-scoped Cheatpaths

At times, it can be useful to closely associate cheatsheets with a directory on your filesystem. cheat facilitates this by searching for a .cheat folder in the current working directory. If found, the .cheat directory will (temporarily) be added to the cheatpaths.

Usage

To view a cheatsheet:

cheat tar      # a "top-level" cheatsheet
cheat foo/bar  # a "nested" cheatsheet

To edit a cheatsheet:

cheat -e tar     # opens the "tar" cheatsheet for editing, or creates it if it does not exist
cheat -e foo/bar # nested cheatsheets are accessed like this

To view the configured cheatpaths:

cheat -d

To list all available cheatsheets:

cheat -l

To list all cheatsheets that are tagged with "networking":

cheat -l -t networking

To list all cheatsheets on the "personal" path:

cheat -l -p personal

To search for the phrase "ssh" among cheatsheets:

cheat -s ssh

To search (by regex) for cheatsheets that contain an IP address:

cheat -r -s '(?:[0-9]{1,3}\.){3}[0-9]{1,3}'

Flags may be combined in intuitive ways. Example: to search sheets on the "personal" cheatpath that are tagged with "networking" and match a regex:

cheat -p personal -t networking --regex -s '(?:[0-9]{1,3}\.){3}[0-9]{1,3}'

Advanced Usage

Shell autocompletion is currently available for the bash and fish shells. Copy the relevant completion script into the appropriate directory on your filesystem to enable autocompletion. (This directory will vary depending on operating system and shell specifics.)

Additionally, cheat supports enhanced autocompletion via integration with fzf. (This feature is currently available on bash only.) To enable fzf integration:

  1. Ensure that fzf is available on your $PATH
  2. Set an envvar: export CHEAT_USE_FZF=true