- [About](#about)
    - [Supported versions](#supported-versions)
- [Installation](#installation)
- [Configuration](#configuration)
- [Labels](#labels)
- [Running](#running)
  - [RSpec](#rspec)
  - [Minitest](#minitest)
  - [Cucumber](#cucumber)
  - [Remote recording](#remote-recording)
  - [Server process recording](#server-process-recording)
- [AppMap for VSCode](#appmap-for-vscode)
- [AppMap Swagger](#appmap-swagger)
- [Uploading AppMaps](#uploading-appmaps)
- [Development](#development)
  - [Running tests](#running-tests)
  - [Using fixture apps](#using-fixture-apps)
    - [`test/fixtures`](#testfixtures)
    - [`spec/fixtures`](#specfixtures)


# About

`appmap-ruby` is a Ruby Gem for recording
[AppMaps](https://github.com/applandinc/appmap) of your code.
"AppMap" is a data format which records code structure (modules, classes, and methods), code execution events
(function calls and returns), and code metadata (repo name, repo URL, commit
SHA, labels, etc). It's more granular than a performance profile, but it's less
granular than a full debug trace. It's designed to be optimal for understanding the design intent and structure of code and key data flows.

There are several ways to record AppMaps of your Ruby program using the `appmap` gem:

* Run your tests (RSpec, Minitest, Cucumber) with the environment variable `APPMAP=true`. An AppMap will be generated for each spec.
* Run your application server with AppMap remote recording enabled, and use the [AppLand
  browser extension](https://github.com/applandinc/appland-browser-extension) to start,
  stop, and upload recordings.
* Wrap some code in an `AppMap.record` block, which returns JSON containing the code execution trace.

Once you have made a recording, there are two ways to view automatically generated diagrams of the AppMaps.

The first option is to load the diagrams directly in your IDE, using the [AppMap extension for VSCode](https://marketplace.visualstudio.com/items?itemName=appland.appmap).

The second option is to upload them to the [AppLand server](https://app.land) using the [AppLand CLI](https://github.com/applandinc/appland-cli/releases).

### Supported versions

* Ruby 2.5, 2.6, 2.7
* Rails 5, 6

Support for new versions is added frequently, please check back regularly for updates.

# Installation

<a href="https://www.loom.com/share/78ab32a312ff4b85aa8827a37f1cb655"> <p>Quick and easy setup of the AppMap gem for Rails - Watch Video</p> <img style="max-width:300px;" src="https://cdn.loom.com/sessions/thumbnails/78ab32a312ff4b85aa8827a37f1cb655-with-play.gif"> </a>


Add `gem 'appmap'` to **beginning** of your Gemfile. We recommend that you add the `appmap` gem to the `:development, :test` group. Your Gemfile should look something like this:

```
source 'https://rubygems.org'
git_source(:github) { |repo| "https://github.com/#{repo}.git" }

# Optional rubRuby version
# ruby '2.7.2'

group :development, :test do
  gem 'appmap'
end
```

Install with `bundle install`, as usual.

It's important to add the `appmap` gem before any other gems that you may want to instrument. There is more about this in the section on adding gems to the *appmap.yml*.

**Railtie**

If you are using Ruby on Rails, require the railtie after Rails is loaded. 

```
# application.rb is a good place to do this, along with all the other railties.
# Don't require the railtie in environments that don't bundle the appmap gem.
require 'appmap/railtie' if defined?(AppMap).
```

**application.rb**

Add this line to *application.rb*, to enable server recording with `APPMAP_RECORD=true`:

```ruby
module MyApp
  class Application < Rails::Application
    ...
  
    config.appmap.enabled = true if ENV['APPMAP_RECORD']
    
    ...
  end
end
```

# Configuration

When you run your program, the `appmap` gem reads configuration settings from `appmap.yml`. Here's a sample configuration
file for a typical Rails project:

```yaml
# 'name' should generally be the same as the code repo name.
name: my_project
packages:
- path: app/controllers
- path: app/models
  # Exclude sub-paths within the package path
  exclude:
  - concerns/accessor
- path: app/jobs
- path: app/helpers
# Include the gems that you want to see in the dependency maps.
# These are just examples.
- gem: activerecord
- gem: devise
- gem: aws-sdk
- gem: will_paginate
# Global exclusion of a class name
exclude:
- MyClass
- MyClass#my_instance_method
- MyClass.my_class_method
functions:
- packages: myapp
  class: ControllerHelper
  function: logged_in_user
  labels: [ authentication ]
```

* **name** Provides the project name (required)
* **packages** A list of source code directories which should be recorded.
* **exclude** A list of classes and/or methods to definitively exclude from recording.
* **functions** A list of specific functions, scoped by package and class, to record.

**packages**

Each entry in the `packages` list is a YAML object which has the following keys:

* **path** The path to the source code directory. The path may be relative to the current working directory, or it may
  be an absolute path.
* **gem** As an alternative to specifying the path, specify the name of a dependency gem. When using `gem`, don't specify `path`. In your `Gemfile`, the `appmap` gem **must** be listed **before** any gem that you specify in your *appmap.yml*.
* **exclude** A list of files and directories which will be ignored. By default, all modules, classes and public
  functions are inspected. See also: global `exclude` list.
* **shallow** When set to `true`, only the first function call entry into a package will be recorded. Subsequent function calls within 
  the same package are not recorded unless code execution leaves the package and re-enters it. Default: `true` when using `gem`,
  `false` when using `path`.

**exclude**

Optional list of fully qualified class and method names. Separate class and method names with period (`.`) for class methods and hash (`#`) for instance methods.

**functions**

Optional list of `class, function` pairs. The `package` name is used to place the function within the class map, and does not have to match
the folder or gem name. The primary use of `functions` is to apply specific labels to functions whose source code is not accessible (e.g., it's in a Gem).
For functions which are part of the application code, use `@label` or `@labels` in code comments to apply labels.

# Labels

The [AppMap data format](https://github.com/applandinc/appmap) provides for class and function `labels`, which can be used to enhance the AppMap visualizations, and to programatically analyze the data.

You can apply function labels using source code comments in your Ruby code. To apply a labels to a function, add a `@label` or `@labels` line to the comment which immediately precedes a function.

For example, if you add this comment to your source code:

```ruby
class ApiKey
  # @labels provider.authentication security
  def authenticate(key)
    # logic to verify the key here...
  end
end
```

Then the AppMap metadata section for this function will include:

```json
  {
    "name": "authenticate",
    "type": "function",
    "labels": [ "provider.authentication", "security" ]
  }
```


# Running

## RSpec

To record RSpec tests, follow these additional steps:

1) Require `appmap/rspec` in your `spec_helper.rb` before any other classes are loaded.

```ruby
require 'appmap/rspec'
```

Note that `spec_helper.rb` in a Rails project typically loads the application's classes this way:

```ruby
require File.expand_path("../../config/environment", __FILE__)
```

and `appmap/rspec` must be required before this:

```ruby
require 'appmap/rspec'
require File.expand_path("../../config/environment", __FILE__)
```

2) Run the tests with the environment variable `APPMAP=true`:

```sh-session
$ APPMAP=true bundle exec rspec
```

Each RSpec test will output an AppMap file into the directory `tmp/appmap/rspec`. For example:

```
$ find tmp/appmap/rspec
Hello_says_hello_when_prompted.appmap.json
```

## Minitest

To record Minitest tests, follow these additional steps:

1) Require `appmap/minitest` in `test_helper.rb`

```ruby
require 'appmap/minitest'
```

Note that `test_helper.rb` in a Rails project typically loads the application's classes this way:

```ruby
require_relative '../config/environment'
```

and `appmap/minitest` must be required before this:

```ruby
require 'appmap/minitest'
require_relative '../config/environment'
```

2) Run your tests as you normally would with the environment variable `APPMAP=true`. For example:  

```
$ APPMAP=true bundle exec rake test
```

or

```
$ APPMAP=true bundle exec ruby -Ilib -Itest test/*_test.rb
```

Each Minitest test will output an AppMap file into the directory `tmp/appmap/minitest`. For example:

```
$ find tmp/appmap/minitest
Hello_says_hello_when_prompted.appmap.json
```

## Cucumber

To record Cucumber tests, follow these additional steps:

1) Require `appmap/cucumber` in `support/env.rb`:

```ruby
require 'appmap/cucumber'
```

Be sure to require it before `config/environment` is required.

2) Create an `Around` hook in `support/hooks.rb` to record the scenario:


```ruby
if AppMap::Cucumber.enabled?
  Around('not @appmap-disable') do |scenario, block|
    appmap = AppMap.record do
      block.call
    end

    AppMap::Cucumber.write_scenario(scenario, appmap)
  end
end
```

3) Run the tests with the environment variable `APPMAP=true`:

```sh-session
$ APPMAP=true bundle exec cucumber
```

Each Cucumber test will output an AppMap file into the directory `tmp/appmap/cucumber`. For example:

```
$ find tmp/appmap/cucumber
Hello_Says_hello_when_prompted.appmap.json
```

## Remote recording

To manually record ad-hoc AppMaps of your Ruby app, use AppMap remote recording.

1. Add the AppMap remote recording middleware. For example, in `config/initializers/appmap_remote_recording.rb`:

```ruby
if defined?(AppMap)
  require 'appmap/middleware/remote_recording'

  Rails.application.config.middleware.insert_after \
    Rails::Rack::Logger,
    AppMap::Middleware::RemoteRecording
end
```

2. Download and unpack the [AppLand browser extension](https://github.com/applandinc/appland-browser-extension). Install into Chrome using `chrome://extensions/`. Turn on "Developer Mode" and then load the extension using the "Load unpacked" button.

3. Start your Rails application server. For example:

```sh-session
$ bundle exec rails server
```

4. Open the AppLand browser extension and push `Start`.

5. Use your app. For example, perform a login flow, or run through a manual UI test.

6. Open the AppLand browser extension and push `Stop`. The recording will be transferred to the AppLand website and opened in your browser.

## Server process recording

Run your Rails server with `APPMAP_RECORD=true`. When the server exits, an *appmap.json* file will be written to the project directory. This is a great way to start the server, interact with your app as a user (or through it's API), and then view an AppMap of everything that happened.

Be sure and set `WEB_CONCURRENCY=1`, if you are using a webserver that can run multiple processes. You only want there to be one process while you are recording, otherwise they will both try and write *appmap.json* and one of them will clobber the other.


# AppMap for VSCode

The [AppMap extension for VSCode](https://marketplace.visualstudio.com/items?itemName=appland.appmap) helps you navigate your code more efficiently with interactive, accurate software architecture diagrams right in your IDE. In less than two minutes you can go from installing the AppMap extension to exploring maps of your code's architecture. AppMap helps you:

* Onboard to code architecture, with no extra work for the team
* Conduct code and design reviews using live and accurate data
* Troubleshoot hard-to-understand bugs using a "top-down" approach.

Each interactive diagram links directly to the source code, and the information is easy to share.

# AppMap Swagger

[appmap_swagger](https://github.com/applandinc/appmap_swagger-ruby) is a tool to generate Swagger files from AppMap data. With `appmap_swagger`, you can add Swagger to your Ruby or Ruby on Rails project, with no need to write or modify code. Use the Swagger UI to interact with your web services API as you build it, and use diffs of Swagger to perform code review of web service changes.

# Uploading AppMaps

[https://app.land](https://app.land) can be used to store, analyze, and share AppMaps.

For instructions on uploading, see the documentation of the [AppLand CLI](https://github.com/applandinc/appland-cli).

# Development
[![Build Status](https://travis-ci.com/applandinc/appmap-ruby.svg?branch=master)](https://travis-ci.com/applandinc/appmap-ruby)

## Running tests

Before running tests, configure `local.appmap` to point to your local `appmap-ruby` directory.
```
$ bundle config local.appmap $(pwd)
```

Run the tests via `rake`:
```
$ bundle exec rake test
```

The `test` target will build the native extension first, then run the tests. If you need
to build the extension separately, run
```
$ bundle exec rake compile
```

## Using fixture apps

### `test/fixtures`

The fixture apps in `test/fixtures` are plain Ruby projects that exercise the basic functionality of the
`appmap` gem. To develop in a fixture, simply enter the fixture directory and `bundle`.

### `spec/fixtures`

The fixture apps in `spec/fixtures` are simple Rack, Rails5, and Rails6 apps.
You can use them to interactively develop and test the recording features of the `appmap` gem.
These fixture apps are more sophisticated than `test/fixtures`, because they include additional 
resources such as a PostgreSQL database.

To build the fixture container images, first run:

```sh-session
$ bundle exec rake build:fixtures:all
```

This will build the `appmap.gem`, along with a Docker image for each fixture app.

Then move to the directory of the fixture you want to use, and provision the environment.
In this example, we use Ruby 2.6.

```sh-session
$ export RUBY_VERSION=2.6
$ docker-compose up -d pg
$ sleep 10s # Or some reasonable amount of time
$ docker-compose run --rm app ./create_app
```

Now you can start a development container.

```sh-session
$ docker-compose run --rm -v $PWD:/app -v $PWD/../../..:/src/appmap-ruby app bash
Starting rails_users_app_pg_1 ... done
root@6fab5f89125f:/app# cd /src/appmap-ruby
root@6fab5f89125f:/src/appmap-ruby# rm ext/appmap/*.so ext/appmap/*.o
root@6fab5f89125f:/src/appmap-ruby# bundle
root@6fab5f89125f:/src/appmap-ruby# bundle exec rake compile
root@6fab5f89125f:/src/appmap-ruby# cd /src/app
root@6fab5f89125f:/src/app# bundle config local.appmap /src/appmap-ruby
root@6fab5f89125f:/src/app# bundle
```

At this point, the bundle is built with the `appmap` gem located  in `/src/appmap`, which is volume-mounted from the host.
So you can edit the fixture code and the appmap code and run test commands such as `rspec` and `cucumber` in the container.
For example:

```sh-session
root@6fab5f89125f:/src/app# bundle exec rspec
Configuring AppMap from path appmap.yml
....

Finished in 0.07357 seconds (files took 2.1 seconds to load)
4 examples, 0 failures
```