page_meta

Easily define <meta> and <link> tags. I18n support for descriptions, keywords and titles.

Installation

gem install page_meta

Or add the following line to your project's Gemfile:

gem "page_meta"

Usage

Your controller and views have an object called page_meta. You can use it to define meta tags and links. By default, it will include the encoding, language and viewport meta tags.

<meta charset="utf-8" />
<meta name="language" content="en" />
<meta itemprop="language" content="en" />
<meta name="viewport" content="width=device-width,initial-scale=1" />

You can use I18n to define titles, descriptions and keywords. These values will be inferred from the controller and action names. For an action SiteController#index you'll need the following translation scope:

en:
  page_meta:
    title_base: "%{value} • MyApp"

    site:
      index:
        title: "Welcome to MyApp"

Previously, you could also use the page_meta.{titles,description,keywords} scopes, but this is now deprecated in favor of the above.

---
en:
  page_meta:
    titles:
      base: "%{value} • MyApp"
      site:
        index: "Welcome to MyApp"

The title without the base context can be accessed through page_meta.title.simple.

<%= page_meta.title %>          // Welcome to MyApp • MyApp
<%= page_meta.title.simple %>   // Welcome to MyApp

Sometimes you need to render some dynamic value. In this case, you can use the I18n placeholders.

---
en:
  page_meta:
    title_base: "%{title} • MyCompany"

    workshops:
      show:
        title: "%{name}"

You can then set dynamic values using the PageMeta::Base#[]=.

class WorkshopsController < ApplicationController
  def show
    @workshop = Workshop.find_by_permalink!(params[:permalink])
    page_meta[:name] = @workshop.name
  end
end

Some actions are aliased, so you don't have to duplicate the translations:

• Action create points to new
• Action update points to edit
• Action destroy points to remove

The same concept is applied to descriptions and keywords.

---
en:
  page_meta:
    base_title: "%{value} • MyApp"
    site:
      show:
        title: "Show"
        description: MyApp is the best way of doing something.
        keywords: "myapp, thing, other thing"

Defining base url

You can define the base url.

page_meta.base "https://example.com/"

Defining meta tags

To define other meta tags, you have to use PageMeta::Base#tag like the following:

class Workshops Controller < ApplicationController
  def show
    @workshop = Workshop.find_by_permalink(params[:permalink])
    page_meta.tag :description, @workshop.description
    page_meta.tag :keywords, @workshop.tags
  end
end

[!TIP]

The meta tag's content can also be any object that responds to the method call. This way you can lazy evaluate the content.

You can define default meta/link tags in a before_action:

class ApplicationController < ActionController::Base
  before_action :set_default_meta

  private

  def set_default_meta
    page_meta.tag :dns_prefetch_control, "http://example.com"
    page_meta.tag :robots, "index, follow"
    page_meta.tag :copyright, "Example Inc."
  end
end

Finally, you can define meta tags for Facebook and Twitter:

# Meta tags for Facebook
page_meta.tag :og, {
  image: helpers.asset_url("fb.png"),
  image_type: "image/png",
  image_width: 800,
  image_height: 600,
  description: @workshop.description,
  title: @workshop.name,
  url: workshop_url(@workshop)
}

# Meta tags for Twitter
page_meta.tag :twitter, {
  card: "summary_large_image",
  title: @workshop.name,
  description: @workshop.description,
  site: "@howto",
  creator: "@fnando",
  image: helpers.asset_url(@workshop.cover_image)
}

Defining link tags

To define link tags, you have to use PageMeta::Base#link like the following:

page_meta.link :canonical, href: article_url(article)
page_meta.link :last, href: article_url(articles.last)
page_meta.link :first, href: article_url(articles.first)

The hash can be any of the link tag's attributes. The following example defines the Safari 9 Pinned Tab icon:

page_meta.link :mask_icon, color: "#4078c0", href: helpers.asset_url("mask_icon.svg")

Rendering the elements

To render all tags, just do something like this:

<!DOCTYPE html>
<html lang="en">
  <head>
    <%= page_meta %>
  </head>
  <body>
    <%= yield %>
  </body>
</html>

Rendering titles and descriptions

You may want to render title and description on your page. In this case, you may use something like this:

<h1><%= page_meta.title.simple %></h1>
<p><%= page_meta.description.simple %></p>

If your description contains HTML, you can use page_meta.description(html: true).simple instead. It will use Rails' html_safe helpers to safely retrieve the translation, just like regular Rails would do. Please read Rails docs for more info.

Removing meta tags

You can use PageMeta::Base#delete to remove meta tags. All matching tags will be removed.

page_meta.delete(:description)

Maintainer

• Nando Vieira

Contributors

• https://github.com/fnando/page_meta/contributors

Contributing

For more details about how to contribute, please read https://github.com/fnando/page_meta/blob/main/CONTRIBUTING.md.

License

The gem is available as open source under the terms of the MIT License. A copy of the license can be found at https://github.com/fnando/page_meta/blob/main/LICENSE.md.

Code of Conduct

Everyone interacting in the page_meta project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.