Mailspring/docs/ComposerExtensions.md
Juan Tejada 9f309d399b update(extensions): Rename DraftStoreExtension and MessageStoreExtension
Summary:
- Rename DraftStoreExtension to ComposerExtension
- Rename MessageStoreExtension to MessageViewExtension
- Rename ContenteditablePlugin to ContenteditableExtension
  - Update Contenteditable to use new naming convention
  - Adds support for extension handlers as props
- Add ExtensionRegistry to register extensions:
  - ContenteditableExtensions will not be registered through the
    ExtensionRegistry. They are meant for internal use, or if anyone wants
    to use our Contenteditable component directly in their plugins.
  - Adds specs
- Refactors internal_packages and src to use new names and new ExtensionRegistry api
- Adds deprecation util function and deprecation notices for old api methods:
  - DraftStore.{registerExtension, unregisterExtension}
  - MessageStore.{registerExtension, unregisterExtension}
  - DraftStoreExtension.{onMouseUp, onTabDown}
  - MessageStoreExtension
- Adds and updates docs

Test Plan: - Unit tests

Reviewers: bengotow, evan

Reviewed By: evan

Differential Revision: https://phab.nylas.com/D2293
2015-11-30 16:08:05 -08:00

46 lines
1.7 KiB
Markdown

---
Title: Extending the Composer
Section: Guides
Order: 6
---
The composer lies at the heart of N1, and many improvements to the mail experience require deep integration with the composer. To enable these sort of plugins, the {DraftStore} exposes an extension API.
This API allows your package to:
- Display warning messages before a draft is sent. (ie: "Are you sure you want to send this without attaching a file?")
- Intercept keyboard and mouse events to the composer's text editor.
- Transform the draft and make additional changes before it is sent.
To create your own composer extensions, subclass {ComposerExtension} and override the methods your extension needs.
In the sample packages repository, [templates]() is an example of a package which uses a ComposerExtension to enhance the composer experience.
### Example
This extension displays a warning before sending a draft that contains the names of competitors' products. If the user proceeds to send the draft containing the words, it appends a disclaimer.
```coffee
{ComposerExtension} = require 'nylas-exports'
class ProductsExtension extends ComposerExtension
@warningsForSending: (draft) ->
words = ['acme', 'anvil', 'tunnel', 'rocket', 'dynamite']
body = draft.body.toLowercase()
for word in words
if body.indexOf(word) > 0
return ["with the word '#{word}'?"]
return []
@finalizeSessionBeforeSending: (session) ->
draft = session.draft()
if @warningsForSending(draft)
bodyWithWarning = draft.body += "<br>This email \
contains competitor's product names \
or trademarks used in context."
session.changes.add(body: bodyWithWarning)
```