Class: Flickr

Inherits:
Object
  • Object
show all
Defined in:
lib/flickr.rb

Overview

Flickr client class. Requires an API key

Defined Under Namespace

Classes: Group, Photo, Photoset, User

Constant Summary collapse

HOST_URL =
'http://flickr.com'
API_PATH =
'/services/rest'
VALID_SIZES =

Flickr, annoyingly, uses a number of representations to specify the size of a photo, depending on the context. It gives a label such a “Small” or “Medium” to a size of photo, when returning all possible sizes. However, when generating the uri for the page that features that size of photo, or the source url for the image itself it uses a single letter. Bizarrely, these letters are different depending on whether you want the Flickr page for the photo or the source uri – e.g. a “Small” photo (240 pixels on its longest side) may be viewed at “www.flickr.com/photos/sco/2397458775/sizes/s/” but its source is at “”. The VALID_SIZES hash associates the correct letter with a label

{ "Square" => ["s", "sq"],
  "Thumbnail" => ["t", "t"],
  "Small" => ["m", "s"],
  "Medium" => [nil, "m"],
  "Large" => ["b", "l"]
}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(api_key_or_params = nil, email = nil, password = nil, shared_secret = nil) ⇒ Flickr

To use the Flickr API you need an api key (see www.flickr.com/services/api/misc.api_keys.html), and the flickr client object shuld be initialized with this. You’ll also need a shared secret code if you want to use authentication (e.g. to get a user’s private photos) There are two ways to initialize the Flickr client. The preferred way is with a hash of params, e.g. ‘api_key’ => ‘your_api_key’, ‘shared_secret’ => ‘shared_secret_code’. The older (deprecated) way is to pass an ordered series of arguments. This is provided for continuity only, as several of the arguments are no longer usable (‘email’, ‘password’)


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# File 'lib/flickr.rb', line 78

def initialize(api_key_or_params=nil, email=nil, password=nil, shared_secret=nil)
  @host = HOST_URL
  @api = API_PATH
  if api_key_or_params.is_a?(Hash)
    @api_key = api_key_or_params['api_key']
    @shared_secret = api_key_or_params['shared_secret']
    @auth_token = api_key_or_params['auth_token']
  else
    @api_key = api_key_or_params
    @shared_secret = shared_secret
    (email, password) if email and password
  end
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(method_id, params = {}) ⇒ Object

Implements everything else. Any method not defined explicitly will be passed on to the Flickr API, and return an XmlSimple document. For example, Flickr#test_echo is not defined, so it will pass the call to the flickr.test.echo method.


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# File 'lib/flickr.rb', line 178

def method_missing(method_id, params={})
  request(method_id.id2name.gsub(/_/, '.'), params)
end

Instance Attribute Details

#api_keyObject (readonly)

Returns the value of attribute api_key.


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# File 'lib/flickr.rb', line 43

def api_key
  @api_key
end

#auth_tokenObject (readonly)

Returns the value of attribute auth_token.


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# File 'lib/flickr.rb', line 43

def auth_token
  @auth_token
end

#userObject

Returns the value of attribute user.


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# File 'lib/flickr.rb', line 44

def user
  @user
end

Instance Method Details

#find_by_url(url) ⇒ Object

Implements flickr.urls.lookupGroup and flickr.urls.lookupUser


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# File 'lib/flickr.rb', line 116

def find_by_url(url)
  response = urls_lookupUser('url'=>url) rescue urls_lookupGroup('url'=>url) rescue nil
  (response['user']) ? User.new(response['user']['id'], nil, nil, nil, @api_key) : Group.new(response['group']['id'], @api_key) unless response.nil?
end

#get_token_from(frob) ⇒ Object

Gets authentication token given a Flickr frob, which is returned when user allows access to their account for the application with the api_key which made the request


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# File 'lib/flickr.rb', line 95

def get_token_from(frob)
  auth_response = request("auth.getToken", :frob => frob)['auth']
  @auth_token = auth_response['token']
  @user = User.new( 'id' => auth_response['user']['nsid'], 
                    'username' => auth_response['user']['username'],
                    'name' => auth_response['user']['fullname'],
                    'client' => self)
  @auth_token
end

#groups(group_name, options = {}) ⇒ Object

Implements flickr.groups.search


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# File 'lib/flickr.rb', line 149

def groups(group_name, options={})
  collection = groups_search({"text" => group_name}.merge(options))['groups']['group']
  collection = [collection] if collection.is_a? Hash
  
  collection.collect { |group| Group.new( "id" => group['nsid'], 
                                          "name" => group['name'], 
                                          "eighteenplus" => group['eighteenplus'],
                                          "client" => self) }
end

#http_get(url) ⇒ Object

Does an HTTP GET on a given URL and returns the response body


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# File 'lib/flickr.rb', line 183

def http_get(url)
  Net::HTTP.get_response(URI.parse(url)).body.to_s
end

#licensesObject

Implements flickr.photos.licenses.getInfo


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# File 'lib/flickr.rb', line 165

def licenses
  photos_licenses_getInfo['licenses']['license']
end

#login(email = '', password = '') ⇒ Object

Stores authentication credentials to use on all subsequent calls. If authentication succeeds, returns a User object. NB This call is no longer in API and will result in an error if called


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# File 'lib/flickr.rb', line 108

def (email='', password='')
  @email = email
  @password = password
  user = request('test.login')['user'] rescue fail
  @user = User.new(user['id'], nil, nil, nil, @api_key)
end

#login_url(perms) ⇒ Object

Returns url for user to login in to Flickr to authenticate app for a user


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# File 'lib/flickr.rb', line 170

def (perms)
  "http://flickr.com/services/auth/?api_key=#{@api_key}&perms=#{perms}&api_sig=#{signature_from('api_key'=>@api_key, 'perms' => perms)}"
end

#photos(*criteria) ⇒ Object

Implements flickr.photos.getRecent and flickr.photos.search


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# File 'lib/flickr.rb', line 122

def photos(*criteria)
  criteria ? photos_search(*criteria) : recent
end

#photos_request(method, params = {}) ⇒ Object

acts like request but returns a list of Photo objects


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# File 'lib/flickr.rb', line 196

def photos_request(method, params={})
  photos = request(method, params)
  collection = photos['photos']['photo'] || []
  collection = [collection] if collection.is_a? Hash
  collection.collect { |photo| Photo.new(photo.delete('id'), @api_key, photo) }
end

#photos_search(params = {}) ⇒ Object Also known as: search


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# File 'lib/flickr.rb', line 132

def photos_search(params={})
  photos_request('photos.search', params)
end

#recentObject

flickr.photos.getRecent 100 newest photos from everyone


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# File 'lib/flickr.rb', line 128

def recent
  photos_request('photos.getRecent')
end

Implements flickr.tags.getRelated


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# File 'lib/flickr.rb', line 160

def related_tags(tag)
  tags_getRelated('tag'=>tag)['tags']['tag']
end

#request(method, params = {}) ⇒ Object

Takes a Flickr API method name and set of parameters; returns an XmlSimple object with the response


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# File 'lib/flickr.rb', line 188

def request(method, params={})
  url = request_url(method, params)
  response = XmlSimple.xml_in(http_get(url), { 'ForceArray' => false })
  raise response['err']['msg'] if response['stat'] != 'ok'
  response
end

#request_url(method, params = {}) ⇒ Object

Builds url for Flickr API REST request from given the flickr method name (exclusing the ‘flickr.’ that begins each method call) and params (where applicable) which should be supplied as a Hash (e.g ‘user_id’ => “foo123”)


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# File 'lib/flickr.rb', line 206

def request_url(method, params={})
  method = 'flickr.' + method
  url = "#{@host}#{@api}/?api_key=#{@api_key}&method=#{method}"
  params.merge!('api_key' => @api_key, 'method' => method, 'auth_token' => @auth_token)
  signature = signature_from(params) 
  
  url = "#{@host}#{@api}/?" + params.merge('api_sig' => signature).collect { |k,v| "#{k}=" + CGI::escape(v.to_s) unless v.nil? }.compact.join("&")
end

#signature_from(params = {}) ⇒ Object


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# File 'lib/flickr.rb', line 215

def signature_from(params={})
  return unless @shared_secret # don't both getting signature if no shared_secret
  request_str = params.reject {|k,v| v.nil?}.collect {|p| "#{p[0].to_s}#{p[1]}"}.sort.join # build key value pairs, sort in alpha order then join them, ignoring those with nil value
  return Digest::MD5.hexdigest("#{@shared_secret}#{request_str}")
end

#tag(tag) ⇒ Object

Gets public photos with a given tag


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# File 'lib/flickr.rb', line 138

def tag(tag)
  photos('tags'=>tag)
end

#users(lookup = nil) ⇒ Object

Implements flickr.people.findByEmail and flickr.people.findByUsername.


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# File 'lib/flickr.rb', line 143

def users(lookup=nil)
  user = people_findByEmail('find_email'=>lookup)['user'] rescue people_findByUsername('username'=>lookup)['user']
  return User.new("id" => user["nsid"], "username" => user["username"], "client" => self)
end