ruby-ess
https://github.com/essfeed/rails-ess
Generate ESS XML feeds with Ruby
Installation
Add this line to your application's Gemfile:
gem 'ess', '~> 0.9.1'
And then execute:
$ bundle
Or install it yourself as:
$ gem install ess -v 0.9.1
Usage
Producing your own ESS feeds is easy. Here is an example about how it's done, with most of the available tags available in ESS:
require 'ess'
ess = Maker.make do |ess|
ess.channel do |channel|
channel.title "National Stadium Football events"
channel.link "http://sample.com/feeds/sample.ess"
channel.id "ESSID:50b4b412-1ad4-a731-1c6a-2523ffa33f81"
channel.published "2012-12-13T08:29:29Z"
channel.updated "2012-12-13T18:30:02-08:00"
channel.rights "Copyright (c) 2013, John Doe"
channel.add_feed do |feed|
feed.title "Football match of saturday"
feed.uri "http://sample.com/events/specific-and-unique-event-page/"
feed.id "EVENTID:550b55b412-1ad4-a4731-155-2777fa37f866"
feed.published "2012-12-13T08:29:29Z"
feed.updated "2012-12-13T18:30:02-0800"
feed.access "PUBLIC"
feed.description("Welcome to my first football match event. " +
"This football match is very important. " +
"Our team is about to go up against our main league competitor.")
feed. do ||
.tag "Sport"
.tag "Footbal"
.tag "Soccer"
.tag "Match"
.tag "Game"
.tag "Team Sport"
.tag "Stadium"
end
feed.categories.add_item(:type => "competition") do |item|
item.name "Football"
item.id "C2AH"
end
feed.dates.add_item do |item|
item.type_attr "recurrent"
item.unit_attr "week"
item.limit_attr "4"
item.selected_day_attr "saturday,sunday"
item.name "Match Date"
item.start "2011-12-13T18:30:02Z"
item.duration "10800"
end
feed.places do |places|
places.add_item(:type => "fixed", :priority => 1) do |item|
item.name "Football Stade"
item.latitude "40.71675"
item.longitude "-74.00674"
item.address "Ave of Americas, 871"
item.city "New York"
item.zip "10001"
item.state_code "NY"
item.country_code "US"
end
places.add_item(:type => "fixed", :priority => 2) do |item|
item.name "Match direct on TV"
item.country_code "US"
item.medium_name "NBC super channel"
item.medium_type "television"
end
end
feed.prices do |prices|
prices.add_item(:type => "standalone", :priority => 2) do |item|
item.mode_attr "invitation"
item.name "Free entrance"
item.value "0"
item.currency "USD"
end
prices.add_item(:type => "recurrent", :priority => 1) do |item|
item.unit_attr "month"
item.mode_attr "fixed"
item.limit_attr "12"
item.name "Subscribe monthly !"
item.value "17"
item.currency "USD"
item.start "2012-12-13T18:30:02Z"
end
end
feed.media do |media|
media.add_item(:type => "image", :priority => 1) do |item|
item.name "Stade image"
item.uri "http://sample.com/small/image_1.png"
end
media.add_item(:type => "video", :priority => 3) do |item|
item.name "Stade video"
item.uri "http://sample.com/video/movie.mp4"
end
media.add_item(:type => "sound", :priority => 2) do |item|
item.name "Radio spot"
item.uri "http://sample.com/video/movie.mp3"
end
media.add_item(:type => "website", :priority => 4) do |item|
item.name "Football Stade website"
item.uri "http://my-football-website.com"
end
end
feed.people do |people|
people.add_item(:type => "organizer") do |item|
item.id "THJP167:8URYRT24:BUEREBK:567TYEFGU:IPAAF"
item.uri "http://michaeldoe.com"
item.name "Michael Doe"
item.firstname "Michael"
item.lastname "Doe"
item.organization "Football club association"
item.address "80, 5th avenue / 45st E - #504"
item.city "New York"
item.zip "10001"
item.state "New York"
item.state_code "NY"
item.country "United States of America"
item.country_code "US"
item.logo "http://sample.com/logo_120x60.png"
item.icon "http://sample.com/icon_64x64.png"
item.email "[email protected]"
item.phone "+001 (646) 234-5566"
end
people.add_item(:type => "performer") do |item|
item.id "FDH56:G497D6:4564DD465:4F6S4S6"
item.uri "http://janettedoe.com"
item.name "Janette Doe"
end
people.add_item(:type => "attendee") do |item|
item.name "Attendees information:"
item.minpeople 0
item.maxpeople 500
item.minage 0
item.restriction "Smoking is not allowed in the stadium"
end
people.add_item(:type => "social") do |item|
item.name "Social network link to share or rate the event."
item.uri "http://social_network.com/my_events/my_friends/my_notes"
end
people.add_item(:type => "author") do |item|
item.name "Feed Powered by Event Promotion Tool"
item.uri "http://sample.com/my_events/"
item.logo "http://sample.com/logo_120x60.png"
item.icon "http://sample.com/icon_64x64.png"
end
people.add_item(:type => "contributor") do |item|
item.name "Jane Doe"
end
end
feed.relations do |relations|
relations.add_item(:type => "alternative") do |item|
item.name "alternative event"
item.id "EVENTID:50412:1a904:a715731:1cera:25va33"
item.uri "http://sample.com/feed/event_2.ess"
end
relations.add_item(:type => "related") do |item|
item.name "related event title"
item.id "EVENTID:50b412:1a35d4:a731:1354c6a:225dg1"
item.uri "http://sample.com/feed/event_3.ess"
end
relations.add_item(:type => "enclosure") do |item|
item.name "nearby event"
item.id "EVENTID:50b12:3451d4:34f5a71:1cf6a:2ff81"
item.uri "http://sample.com/feed/event_5.ess"
end
end
end
end
end
As can be seen, it's a very Builder-like DSL. The result of this code will be an ESS feed with one item. To get XML from it, the 'to_xml!' method ca be used.
More information on ESS and what tags and options are available can be found on http://essfeed.org/ .
Pushing feeds to aggregators
Once a feed is generated, it can be submitted to an aggregator easily. To send it to the default aggregator service, which is Hypecal, just add an option to the 'make' class method:
ess = Maker.make(:push => true) do |ess|
...
end
Another way to do the same is to first generate the feed and assign the result to a variable, like 'ess' in previous example, and call its 'push_to_aggregators' method. It accepts the same options and is useful for example when the feed has to be submitted in a dalayed job.
In a Rails environment, if the feed is generated in response to a request, providing the request object to the maker method could provide the aggregator with more useful data:
ess = Maker.make(:request => request) do |ess|
...
end
Should you want to provide a list of aggregator services yourself, it can be done with the aggregators option:
ess = Maker.make(:aggregators => ['http://aggregator.example.com/api.json', ...]) do |ess|
...
end
Another option is to set a new default list of aggregator services using the Pusher class:
ESS::Pusher.aggregators = ['http://aggregator.example.com/api.json', ...]
Validation
When using the Maker class, the resulting feed is validated automatically at the end of the block. That means that before the block ends, the feed has to have all the mandatory tags, with valid values. There is however an option to turn that behavior off, but there should be a good reason to do that.
ess = Maker.make(:validate => false) do |ess|
...
end
The resulting object accepts the 'valid?' and 'validate' methods. The former returns true or false, while the later raises an exception with a message more useful for debugging.
Working with tags
A tag with text can be specified like this:
ess = Maker.make do |ess|
ess.channel do |channel|
channel.title "National Stadium Football events"
...
end
end
Each tag accepts method calls coresponding to child tag names. These methods can accept a string argument, which will become the text of the child tag, and/or a list of key/value pairs (options), which will become tag attributes.
If there is also a block, it should expect one parameter which will be a reference to the child tag.
For the case where a single tag can have multiple child tags with the same name, the following construct can be used:
ess = Maker.make do |ess|
ess.channel do |channel|
channel.add_feed do |feed|
...
end
channel.add_feed do |another_feed|
...
end
end
end
end
For every tag 'tag_name' its parent accepts an 'add_tag_name' method, which accepts the same arguments as a 'tag_name' method.
Attributes have also their own methods for setting them, for example:
ess = Maker.make do |ess|
ess.lang_attr "zu"
...
end
Here the 'lang' attribute of the ess tag is set to "zu". And there is also a 'text!' method, which can be used to set a tags text:
ess = Maker.make do |ess|
ess.channel do |channel|
channel.title do |title|
title.text! "National Stadium Football events"
end
...
end
end
Again, more information on ESS and what tags and options are available can be found on http://essfeed.org/ .
Valid tag and attribute values
Pretty much anything can be used as the value for a tag, as long as it can be converted to a string with #to_s.
Tags that accept date or time will accept Time objects too, which will be converted to the corrent format, which is ISO-8601 for ESS. However, if the value is a string, an attempt will be made to automatically convert the value to the ISO-8601 format.
IDs
The channel and feed ID tags can also be computed automatically, they don't need to be set by hand. They are automatically calculated and set the first time the TITLE or URI/LINK tags are changed. Also, instead of using a valid ID value, any string can be assigned to the ID tag of a channel or feed, and if it doesn't start with "ESSID:" or "EVENTID:", it will be regenerated using that string as the key.
Contributing
- Fork it
- Create your feature branch (
git checkout -b my-new-feature) - Commit your changes (
git commit -am 'Add some feature') - Push to the branch (
git push origin my-new-feature) - Create new Pull Request
License
(The MIT License)
Copyright (c) 2013 Hypecal
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.