fisher/man/man7/fisher-plugins.md

fisher-plugins(7) -- Creating Fisherman Plugins
===============================================

## DESCRIPTION

This document describes how to create Fisherman plugins. This includes stand-alone utilities, prompts, extension commands and configuration plugins.

There is no technical distinction between any of the terms aforementioned, but there is a *conceptual* difference.

## DEFINITIONS

* `Standalone Utilities`: Plugins that define one or more functions, meant to be used at the command line.

* `Prompts / Themes`: Plugins that modify the appearance of the fish prompt by defining a `fish_prompt` and / or `fish_right_prompt` functions.

* `Extension Commands`: Plugins that extend Fisherman default commands. An extension plugin must define one or more functions like `fisher_<my_command>`. For specific information about commands, see `fisher help commands` and then return to this guide.

* `Configuration Plugins`: Plugins that include one or more `my_plugin.config.fish` files. Files that follow this convention are evaluated at the start of the session.

The following tree is that of a plugin that displays the characteristics of all the plugins described above.

```
my_plugin
|-- fisher_my_plugin.fish
|-- my_plugin.fish
|-- fish_prompt.fish
|-- fish_right_prompt.fish
|-- my_plugin.config.fish
|-- functions/
|   |-- my_plugin_helper.fish
|-- completions/
|   |-- my_plugin.fish
|-- man/
    |-- man1/
        |-- my_plugin.1
```

Plugins may list any number of dependencies to other plugins using a *fishfile*, see `fisher help fishfile`.

Plugins may also define completions using `complete(1)` and provide documentation in the form of `man(1)` pages.

## EXAMPLE

This section walks you through creating *wtc*, a stand-alone plugin based in *github.com/ngerakines/commitment* random commit message generator.


* Navigate to your preferred workspace and create the plugin's directory and Git repository:

```
mkdir -p my/workspace/wtc; and cd my/workspace/wtc
git init
git remote add origin https://github.com/<owner>/wtc
```

* Add the implementation.

```
cat > wtc.fish

function wtc -d "Generate a random commit message"
    switch "$argv"
        case -h --help
            printf "usage: wtc [--help]\n\n"
            printf "  -h --help  Show usage help\n"
            return
    end
    curl -s whatthecommit.com/index.txt
end
^C
```

* Add completions. *wtc* is simple enough that you could get away without `__fisher_parse_help`, but more complex utilities, or utilities whose CLI evolves over time, can benefit using automatic completion generation. Note that in order to use `__fisher_parse_help`, your command must provide a `--help` option that prints usage information to standard output.

```
mkdir completions
cat > completions/wtc.fish

set -l IFS ";"
wtc --help | __fisher_parse_help | while read -l info long short
    complete -c wtc -s "$short" -l "$long" -d "$info"
end
^C
```

* Add basic documentation. Fisherman uses standard manual pages for displaying help information. There are utilities that can help you generate man pages from other text formats, such as Markdown. One example is `ronn(1)`. For this example, type will do:

```
mkdir -p man/man1
cat > man/man1/wtc.1

 .TH man 1 "Today" "1.0" "wtc man page"
 .SH NAME
 wtc \- Generate a random commit message
 .SH SYNOPSIS
 wtc [--help]
 .SH OPTIONS
 -h, --help: Display help information.
 .SH SEE ALSO
 https://github.com/ngerakines/commitment
^C
```

* Commit changes and push to the remote repository.

```
git add --all
git commit -m "What the commit? 1.0"
git push origin master
```

* Install with Fisherman. If you would like to submit your package for registration install the `submit` plugin or send a pull request to the main index repository in *https://github.com/fisherman/index*. See `Index` in `fisher help tour`.

```
fisher install github/*owner*/wtc
wtc
(\ /)
(O.o)
(> <) Bunny approves these changes.
```


## SEE ALSO

man(1)<br>
complete(1)<br>
fisher help commands<br>
fisher help fishfile<br>