RunDOC

This library allows you to "run" your docs and embed the code as well as results back into the documentation. Here's a quick example:

Write documentation:

Install by running:

```
:::>> $ gem install rails --no-document
```

Now if you "run" this document you'll get this output:

Install by running:

```
$ gem install rails --no-document
Successfully installed rails-5.2.2
1 gem installed
```

The idea is that as your documentation "runs" it builds a working tutorial. It also acts as tests since if your docs become incorrect due to a typo or bit-rot then when you try to generate them, the process will fail.

Think of RunDOC as your ever-vigilant tech editor and writing partner.

This software is distributed as a Rubygem. Install it manually:

$ gem install rundoc

or add it to your Gemfile:

gem 'rundoc'

Run the rundoc build command on any markdown file

$ bin/rundoc build --path <test/fixtures/rails_7/rundoc.md>

Note: This command will create and manipulate directories in the working directory of your source markdown file. Best practice is to have your source markdown file in its own empty directory.

This will generate a project folder with your project in it, and a markdown README.md with the parsed output of the markdown docs, and a copy of the source.

• Understanding the Syntax
• Dotenv support
• Rendering cheat sheet

• Execute Bash Commands
  • $
  • fail.$
• Chain commands
  • pipe
  • |
• Manipulate Files
  • file.write
  • file.append
  • file.remove
• Boot background processes such as a local server
  • background.start
  • background.stop
  • background.log.read
  • background.log.clear
• Take screenshots
  • website.visit
  • website.nav
  • website.screenshot
• Configure RunDOC
  • rundoc.configure
• Import and compose documents
  • rundoc.depend_on
  • rundoc.require

RunDOC uses GitHub flavored markdown. This means you write like normal but in your code sections you can add special annotations that when run through RunDOC can generate a project.

All RunDOC commands are prefixed with three colons ::: and are inclosed in a code block a command such as $ which is an alias for bash commands like this:

```
:::>- $ git init .
```

Nothing before the three colons matters. The space between the colons and the command is optional.

If you don't want the command to output to your markdown document you can add a minus symbol - to the end to prevent it from being rendered.

```
:::-- $ git init .
```

Note: If all commands inside of a code block are hidden, the entire codeblock will not be rendered.

If you want the output of the actual command to be rendered to the screen you can use two arrows so that:

```
:::>> $ ls
```

This code block might generate an output something like this to your markdown doc:

```
$ ls
    Gemfile   README.rdoc app   config.ru doc   log   script    tmp
    Gemfile.lock  Rakefile  config    db    lib   public    test    vendor
```

Any items below the command will be passed into the stdin of the command. For example using a $ command you can effectively pipe contents to stdin:

```
:::>> $ tail -n 2
foo
bar
baz
bahz
```

Would output:

$ tail -n 2
baz
bahz

This STDIN feature could be useful if you are running an interactive command such as play new which requires user input.

Different commands will do different things with this input. For example the rundoc command executes Ruby configuration code:

```
:::-- rundoc
Rundoc.configure do |config|
  config.after_build do
    puts "you could push to GitHub here"
    puts "You could do anything here"
    puts "This code will run after the docs are done building"
  end
end
```

And the website.visit command allows you to navigate and manipulate a webpage via a Capybara API:

```
:::>> website.visit(name: "localhost", url: "http://localhost:3000", scroll: 100)
session.execute_script "window.scrollBy(0,100)"
session.click("sign up")
```

RunDOC only cares about things that come after a ::: section. If you have a "regular" code section, it will be rendered as as normal:

```
$ echo "I won't run since i'm missing the :::>> at the front"
```

You can mix non-command code and commands, as long as the things that aren't rendering come first. This can be used to "fake" a command, for example:

$ rails new myapp # Not a command since it's missing the ":::>>""
:::-> $ rails new myapp --skip-test --skip-yarn --skip-sprockets
:::>> | $ head -n 5

This will render as:

$ rails new myapp # Not a command since it's missing the ":::>>""
      create
      create  README.md
      create  Rakefile
      create  .ruby-version
      create  config.ru

It looks like the command was run without any flags, but in reality rails new myapp --skip-test --skip-yarn --skip-sprockets | head -n 5 was executed.

An arrow > is shorthand for "render this" and a dash - is shorthand for skip this section. The two positions are command first and result second.

• :::>- (YES command output, not result output)
• :::>> (YES command output, YES result output)
• :::-- (not command output, not result output)
• :::-> (not command output, YES result output)

Current Commands:

• $
• fail.$

Anything you pass to $ will be run in a shell. If a shell command returns a non-zero exit status an error will be raised. If you expect a non-zero exit status use fail.$ instead:

```
:::>> fail.$ cat /dev/null/foo
```

Even though this command returns a non zero exit status, the contents of the command will be written since we're stating that we don't care if the command fails. This would be the output:

```
$ cat /dev/null/foo
cat: /dev/null/foo: Not a directory
```

Some commands may be custom, for example when running cd you likely want to change the working directory that your script is running in. To do this we need to run Dir.chdir instead of shelling out. So this works as you would expect:

```
:::>> $ cd myapp/config
:::>> $ cat database.yml
```

However this command would fall on its face:

```
:::>> $ cd myapp && cat config/database.yml
:::>> $ rails g scaffold users # <=== This command would be in the wrong directory, not `myapp`
```

These custom commands are kept to a minimum, and for the most part behave as you would expect them to. Write your docs as you normally would and check the output frequently.

Running shell commands like this can be very powerful, you'll likely want more control of how you manipulate files in your project. To do this you can use the file. namespace:

Current Commands:

• file.write
• file.append
• file.remove

Use the file.write keyword followed by a filename, on the next line(s) put the contents of the file:

```
:::>- file.write config/routes.rb

Example::Application.routes.draw do
  root        :to => "pages#index"

  namespace :users do
    resources :after_signup
  end
end
```

If the exact filename is not known you can use a file glob (*).

If you wanted to change users to products you could write to the same file again.

```
:::>- file.write config/routes.rb
Example::Application.routes.draw do
  root        :to => "pages#index"

  namespace :products do
    resources :after_signup
  end
end
```

To fully delete files use bash $ command such as ::: $ rm foo.rb.

To add contents to a file you can use file.append

```
:::>> file.append myapp/Gemfile
gem 'pg'
gem 'sextant', group: :development
gem 'wicked'
gem 'opro'
```

The contents of the file (in this example a file named Gemfile) will remain unchanged, but the contents of the file.append block will now appear in the bottom of the file. If you want to append the contents to a specific part of the file instead of the end of the file you can specify line number by putting a hash (#) then a number following it.

```
:::>> file.append myapp/Gemfile#22
gem 'rails_12factor'
```

This will add the gem 'rails_12factor' on line 22 of the file myapp/Gemfile. If line 22 has existing contents, they will be bumped down to line 23.

Some times you may want to remove a small amount of text from an existing file. You can do this using file.remove, you pass in the contents you want removed:

```
:::>> file.remove myapp/Gemfile
gem 'sqlite3'
```

When this is run, the file Gemfile will be modified to not include gem 'sqlite3'.

Note: file.remove currently requires a very explicit match so things like double versus single quotes, whitespace, and letter case all matter. Current best practice is to only use it for single line removals.

Commands:

• |
• pipe (aliased |)

Sometimes you need to need to pass data from one command to another. To do this there is a provided pipe command |.

Let's say you want to output the first 23 lines of a file but you don't want to confuse your users with an additional pipe command in your shell line you could write something like this:

:::>  $ cat config/database.yml
:::>> | $ head -n 23

Anything after the pipe | will generate a new command with the output of the previous command passed to it. The pipe command will only ouput its result, so the user will not know it was even executed.

This command is currently hacked together, and needs a refactor. Use it, but if something does not behave as you would expected open an issue and explain it.

Sometimes you want to start a long lived process like a server in the background. In that case, the background namespace has your, well, back.

To start a process, pass in the command as the first arg, and give it a name (so it can be referenced later):

:::>> background.start("rails server", name: "server")

You can make the background process wait until it receives a certain string in the logs. For instance to make sure that the server is fully booted:

:::>> background.start("rails server", name: "server", wait: "Listening on")

You can stop the process by referencing the name:

:::-- background.stop(name: "server")

You can also get the log contents:

:::>> background.log.read(name: "server")

You can also truncate the logs:

:::>> background.log.clear(name: "server")

You'll need selenium and chromedriver installed on your system to make screenshots work. On a mac you can run:

$ brew cask install chromedriver

To take a screenshot first "visit" a website. The values you pass in to stdin can be used to further navigate. For more information see the Capybara DSL. Use the keyword session

Once you're on the page you want to capture you can execute website.screenshot:

:::>> website.visit(name: "localhost", url: "http://localhost:3000", scroll: 100)
session.execute_script "window.scrollBy(0,100)"
session.first(:link, "sign up").click

:::>> website.screenshot(name: "localhost")

The result of the screenshot command will be to replace the code section with a markdown link to a relative path of the screenshot.

Once you've visited a website you can further navigate using website.nav or website.navigate:

:::>> website.visit(name: "localhost", url: "http://localhost:3000")
:::>> website.navigate(name: "localhost")
session.execute_script "window.scrollBy(0,100)"
session.first(:link, "sign up").click

:::>> website.screenshot(name: "localhost")

You can specify that you want to upload files to S3 instead of hosting them locally by passing in upload: "s3" to the screenshot command:

:::>> website.visit(name: "localhost", url: "http://localhost:3000", scroll: 100)
:::>> website.screenshot(name: "localhost", upload: "s3")

To authorize, you'll need to set these environment variables:

AWS_ACCESS_KEY_ID
AWS_REGION
AWS_SECRET_ACCESS_KEY
AWS_BUCKET_NAME

The bucketeer addon on Heroku is supported out of the box. To specify project specific environment variables see the "dotenv" section below.

If you're writing multiple tutorials that all are used together to build one larger project then you can declare dependencies inside of your RunDOC document.

For example on day two (day_two/rundoc.md) of the tutorials you could:

:::-- rundoc.depend_on "../day_one/rundoc.md"

Now when you build day_two/rundoc.md it will also run the steps in day_one/rundoc.md first. This way you don't have to copy and paste previous commands.

You can also break up your document into smaller components:

:::>> rundoc.require "../shared/rails_new.md"

This will replace the code section with the generated contents of rundoc.require.

If you need to specify project specific environment variables create a file called .env at the same directory as your rundoc.md and it will be imported. Add this file to your .gitignore so you don't accidentally share with the world

You can configure your docs in your docs use the RunDOC command

```
:::-- rundoc.configure
```

Note: Make sure you run this as a hidden command (with -).

After Build

This will eval any code you put under that line (in Ruby). If you want to run some code after you're done building your docs you could use Rundoc.configure block and call the after_build method like this:

```
:::-- rundoc.configure
Rundoc.configure do |config|
  config.after_build do
    puts "you could push to GitHub here"
    puts "You could do anything here"
    puts "This code will run after the docs are done building"
  end
end
```

Project Root

By default your app builds in a tmp directory. If any failures occur the results will remain in tmp. On a successful build the contents are copied over to project. If you are generating a new rails project in your code $ rails new myapp. Then the finished directory would be in project/myapp. If you don't like the ./project prefix you could tell RunDOC to output contents in ./myapp instead.

```
:::-- rundoc.configure
Rundoc.configure do |config|
  config.project_root = "myapp"
end
```

This will also be the root directory that the after_build is executed in.

Filter Sensitive Info

Sometimes sensitive info like usernames, email addresses, or passwords may be introduced to the output readme. Let's say that your email address was schneems@example.com you could filter this out of your final document and replace it with developer@example.com instead like this:

```
:::-- rundoc.configure
Rundoc.configure do |config|
  config.filter_sensitive("schneems@example.com" => "developer@example.com")
end
```

This command filter_sensitive can be called multiple times with different values. Since the config is in Ruby you could iterate over an array of sensitive data

All content Copyright Richard Schneeman © 2020