alchemyapi.rb

#	Copyright 2013 AlchemyAPI
#
#   Licensed under the Apache License, Version 2.0 (the "License");
#   you may not use this file except in compliance with the License.
#   You may obtain a copy of the License at
#
#       http://www.apache.org/licenses/LICENSE-2.0
#
#   Unless required by applicable law or agreed to in writing, software
#   distributed under the License is distributed on an "AS IS" BASIS,
#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#   See the License for the specific language governing permissions and
#   limitations under the License.


require 'rubygems'
require 'net/http'
require 'uri'
require 'json'

class AlchemyAPI

	#Setup the endpoints
	@@ENDPOINTS = {}
	@@ENDPOINTS['sentiment'] = {}
	@@ENDPOINTS['sentiment']['url'] = '/url/URLGetTextSentiment'
	@@ENDPOINTS['sentiment']['text'] = '/text/TextGetTextSentiment'
	@@ENDPOINTS['sentiment']['html'] = '/html/HTMLGetTextSentiment'
	@@ENDPOINTS['sentiment_targeted'] = {}
	@@ENDPOINTS['sentiment_targeted']['url'] = '/url/URLGetTargetedSentiment'
	@@ENDPOINTS['sentiment_targeted']['text'] = '/text/TextGetTargetedSentiment'
	@@ENDPOINTS['sentiment_targeted']['html'] = '/html/HTMLGetTargetedSentiment'
	@@ENDPOINTS['author'] = {}
	@@ENDPOINTS['author']['url'] = '/url/URLGetAuthor'
	@@ENDPOINTS['author']['html'] = '/html/HTMLGetAuthor'
	@@ENDPOINTS['keywords'] = {}
	@@ENDPOINTS['keywords']['url'] = '/url/URLGetRankedKeywords'
	@@ENDPOINTS['keywords']['text'] = '/text/TextGetRankedKeywords'
	@@ENDPOINTS['keywords']['html'] = '/html/HTMLGetRankedKeywords'
	@@ENDPOINTS['concepts'] = {}
	@@ENDPOINTS['concepts']['url'] = '/url/URLGetRankedConcepts'
	@@ENDPOINTS['concepts']['text'] = '/text/TextGetRankedConcepts'
	@@ENDPOINTS['concepts']['html'] = '/html/HTMLGetRankedConcepts'
	@@ENDPOINTS['entities'] = {}
	@@ENDPOINTS['entities']['url'] = '/url/URLGetRankedNamedEntities'
	@@ENDPOINTS['entities']['text'] = '/text/TextGetRankedNamedEntities'
	@@ENDPOINTS['entities']['html'] = '/html/HTMLGetRankedNamedEntities'
	@@ENDPOINTS['category'] = {}
	@@ENDPOINTS['category']['url']  = '/url/URLGetCategory'
	@@ENDPOINTS['category']['text'] = '/text/TextGetCategory'
	@@ENDPOINTS['category']['html'] = '/html/HTMLGetCategory'
	@@ENDPOINTS['relations'] = {}
	@@ENDPOINTS['relations']['url']  = '/url/URLGetRelations'
	@@ENDPOINTS['relations']['text'] = '/text/TextGetRelations'
	@@ENDPOINTS['relations']['html'] = '/html/HTMLGetRelations'
	@@ENDPOINTS['language'] = {}
	@@ENDPOINTS['language']['url']  = '/url/URLGetLanguage'
	@@ENDPOINTS['language']['text'] = '/text/TextGetLanguage'
	@@ENDPOINTS['language']['html'] = '/html/HTMLGetLanguage'
	@@ENDPOINTS['text'] = {}
	@@ENDPOINTS['text']['url']  = '/url/URLGetText'
	@@ENDPOINTS['text']['html'] = '/html/HTMLGetText'
	@@ENDPOINTS['text_raw'] = {}
	@@ENDPOINTS['text_raw']['url']  = '/url/URLGetRawText'
	@@ENDPOINTS['text_raw']['html'] = '/html/HTMLGetRawText'
	@@ENDPOINTS['title'] = {}
	@@ENDPOINTS['title']['url']  = '/url/URLGetTitle'
	@@ENDPOINTS['title']['html'] = '/html/HTMLGetTitle'
	@@ENDPOINTS['feeds'] = {}
	@@ENDPOINTS['feeds']['url']  = '/url/URLGetFeedLinks'
	@@ENDPOINTS['feeds']['html'] = '/html/HTMLGetFeedLinks'
	@@ENDPOINTS['microformats'] = {}
	@@ENDPOINTS['microformats']['url']  = '/url/URLGetMicroformatData'
	@@ENDPOINTS['microformats']['html'] = '/html/HTMLGetMicroformatData'
	@@ENDPOINTS['taxonomy'] = {}
	@@ENDPOINTS['taxonomy']['url']  = '/url/URLGetRankedTaxonomy'
	@@ENDPOINTS['taxonomy']['text'] = '/text/TextGetRankedTaxonomy'
	@@ENDPOINTS['taxonomy']['html'] = '/html/HTMLGetRankedTaxonomy'
	@@ENDPOINTS['combined'] = {}
	@@ENDPOINTS['combined']['url'] = '/url/URLGetCombinedData'
	@@ENDPOINTS['combined']['text'] = '/text/TextGetCombinedData'
	@@ENDPOINTS['image_extract'] = {}
	@@ENDPOINTS['image_extract']['url'] = '/url/URLGetImage'
	@@ENDPOINTS['image_tag'] = {}
	@@ENDPOINTS['image_tag']['url'] = '/url/URLGetRankedImageKeywords'
	@@ENDPOINTS['image_tag']['image'] = '/image/ImageGetRankedImageKeywords'
		
	@@BASE_URL = 'http://access.alchemyapi.com/calls'
	
	
	def initialize()
	
		begin
			key = File.read('api_key.txt')
			key.strip!

			if key.empty?
				#The key file should't be blank
				puts 'The api_key.txt file appears to be blank, please copy/paste your API key in the file: api_key.txt'
				puts 'If you do not have an API Key from AlchemyAPI please register for one at: http://www.alchemyapi.com/api/register.html'			
				Process.exit(1)
			end
			
			if key.length != 40
				#Keys should be exactly 40 characters long
				puts 'It appears that the key in api_key.txt is invalid. Please make sure the file only includes the API key, and it is the correct one.'
				Process.exit(1)
			end

			@apiKey = key
		rescue => err
			#The file doesn't exist, so show the message and create the file.
			puts 'API Key not found! Please copy/paste your API key into the file: api_key.txt'
			puts 'If you do not have an API Key from AlchemyAPI please register for one at: http://www.alchemyapi.com/api/register.html'
		
			#create a blank file to hold the key
			File.open("api_key.txt", "w") {}
			Process.exit(1)
		end
	end





	# Calculates the sentiment for text, a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/sentiment-analysis/
	# For the docs, please refer to: http://www.alchemyapi.com/api/sentiment-analysis/
	# 
	# INPUT:
	# flavor -> which version of the call, i.e. text, url or html.
	# data -> the data to analyze, either the text, the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	# 
	# Available Options:
	# showSourceText -> 0: disabled (default), 1: enabled
 	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
 	#
	def sentiment(flavor, data, options = {})
		unless @@ENDPOINTS['sentiment'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'sentiment analysis for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['sentiment'][flavor], options)
	end


	# Calculates the targeted sentiment for text, a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/sentiment-analysis/
	# For the docs, please refer to: http://www.alchemyapi.com/api/sentiment-analysis/
	#
	# INPUT:
	# flavor -> which version of the call, i.e. text, url or html.
	# data -> the data to analyze, either the text, the url or html code.
	# target -> the word or phrase to run sentiment analysis on.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#	
	# Available Options:
	# showSourceText	-> 0: disabled, 1: enabled
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def sentiment_targeted(flavor, data, target, options = {})
		if target == '' || target == nil
			return { 'status'=>'ERROR', 'statusMessage'=>'targeted sentiment requires a non-null target' }
		end

		unless @@ENDPOINTS['sentiment_targeted'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'targeted sentiment analysis for ' + flavor + ' not available' }
		end

		#Add the URL encoded data and the target to the options and analyze
		options[flavor] = data
		options['target'] = target
		return analyze(@@ENDPOINTS['sentiment_targeted'][flavor], options)
	end


	# Extracts the entities for text, a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/entity-extraction/ 
	# For the docs, please refer to: http://www.alchemyapi.com/api/entity-extraction/
	#
	# INPUT:
	# flavor -> which version of the call, i.e. text, url or html.
	# data -> the data to analyze, either the text, the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	# 
	# Available Options:
	# disambiguate -> disambiguate entities (i.e. Apple the company vs. apple the fruit). 0: disabled, 1: enabled (default)
	# linkedData -> include linked data on disambiguated entities. 0: disabled, 1: enabled (default) 
	# coreference -> resolve coreferences (i.e. the pronouns that correspond to named entities). 0: disabled, 1: enabled (default)
	# quotations -> extract quotations by entities. 0: disabled (default), 1: enabled.
	# sentiment -> analyze sentiment for each entity. 0: disabled (default), 1: enabled. Requires 1 additional API transction if enabled.
	# showSourceText -> 0: disabled (default), 1: enabled 
	# maxRetrieve -> the maximum number of entities to retrieve (default: 50)
	# 
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def entities(flavor, data, options = {})
		unless @@ENDPOINTS['entities'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'entity extraction for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['entities'][flavor], options)
	end


	# Extracts the author from a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/author-extraction/
	# For the docs, please refer to: http://www.alchemyapi.com/api/author-extraction/
	#
	# INPUT:
	# flavor -> which version of the call, i.e. text, url or html.
	# data -> the data to analyze, either the text, the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# none
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def author(flavor, data, options = {})
		unless @@ENDPOINTS['author'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'author extraction for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['author'][flavor], options)
	end


	# Extracts the keywords from text, a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/keyword-extraction/
	# For the docs, please refer to: http://www.alchemyapi.com/api/keyword-extraction/
	#
	# INPUT:
	# flavor -> which version of the call, i.e. text, url or html.
	# data -> the data to analyze, either the text, the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#		
	# Available Options:
	# keywordExtractMode -> normal (default), strict
	# sentiment -> analyze sentiment for each keyword. 0: disabled (default), 1: enabled. Requires 1 additional API transaction if enabled.
	# showSourceText -> 0: disabled (default), 1: enabled.
	# maxRetrieve -> the max number of keywords returned (default: 50)
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#	
	def keywords(flavor, data, options = {})
		unless @@ENDPOINTS['keywords'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'keyword extraction for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['keywords'][flavor], options)
	end

	
	# Tags the concepts for text, a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/concept-tagging/
	# For the docs, please refer to: http://www.alchemyapi.com/api/concept-tagging/ 
	#
	# Available Options:
	# maxRetrieve -> the maximum number of concepts to retrieve (default: 8)
	# linkedData -> include linked data, 0: disabled, 1: enabled (default)
	# showSourceText -> 0:disabled (default), 1: enabled
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def concepts(flavor, data, options = {})
		unless @@ENDPOINTS['concepts'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'concept tagging for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['concepts'][flavor], options)
	end


	# Categorizes the text for text, a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/text-categorization/
	# For the docs, please refer to: http://www.alchemyapi.com/api/text-categorization/
	#
	# INPUT:
	# flavor -> which version of the call, i.e. text, url or html.
	# data -> the data to analyze, either the text, the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# showSourceText -> 0: disabled (default), 1: enabled
	# 
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def category(flavor, data, options = {})
		unless @@ENDPOINTS['category'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'text categorization for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['category'][flavor], options)
	end


	# Extracts the relations for text, a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/relation-extraction/ 
	# For the docs, please refer to: http://www.alchemyapi.com/api/relation-extraction/
	#
	# INPUT:
	# flavor -> which version of the call, i.e. text, url or html.
	# data -> the data to analyze, either the text, the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# sentiment -> 0: disabled (default), 1: enabled. Requires one additional API transaction if enabled.
	# keywords -> extract keywords from the subject and object. 0: disabled (default), 1: enabled. Requires one additional API transaction if enabled.
	# entities -> extract entities from the subject and object. 0: disabled (default), 1: enabled. Requires one additional API transaction if enabled.
	# requireEntities -> only extract relations that have entities. 0: disabled (default), 1: enabled.
	# sentimentExcludeEntities -> exclude full entity name in sentiment analysis. 0: disabled, 1: enabled (default)
	# disambiguate -> disambiguate entities (i.e. Apple the company vs. apple the fruit). 0: disabled, 1: enabled (default)
	# linkedData -> include linked data with disambiguated entities. 0: disabled, 1: enabled (default).
	# coreference -> resolve entity coreferences. 0: disabled, 1: enabled (default)  
	# showSourceText -> 0: disabled (default), 1: enabled.
	# maxRetrieve -> the maximum number of relations to extract (default: 50, max: 100)
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def relations(flavor, data, options = {})
		unless @@ENDPOINTS['relations'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'relation extraction for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['relations'][flavor], options)
	end


	# Detects the language for text, a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/api/language-detection/ 
	# For the docs, please refer to: http://www.alchemyapi.com/products/features/language-detection/
	#
	# INPUT:
	# flavor -> which version of the call, i.e. text, url or html.
	# data -> the data to analyze, either the text, the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# none
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object.
	#
	def language(flavor, data, options = {})
		unless @@ENDPOINTS['language'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'language detection for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['language'][flavor], options)
	end


	# Extracts the cleaned text (removes ads, navigation, etc.) for text, a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/text-extraction/
	# For the docs, please refer to: http://www.alchemyapi.com/api/text-extraction/
	# 
	# INPUT:
	# flavor -> which version of the call, i.e. text, url or html.
	# data -> the data to analyze, either the text, the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# useMetadata -> utilize meta description data, 0: disabled, 1: enabled (default)
	# extractLinks -> include links, 0: disabled (default), 1: enabled.
	# 
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def text(flavor, data, options = {})
		unless @@ENDPOINTS['text'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'clean text extraction for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['text'][flavor], options)
	end


	# Extracts the raw text (includes ads, navigation, etc.) for a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/text-extraction/ 
	# For the docs, please refer to: http://www.alchemyapi.com/api/text-extraction/
	# 
	# INPUT:
	# flavor -> which version of the call, i.e. text, url or html.
	# data -> the data to analyze, either the text, the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# none
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def text_raw(flavor, data, options = {})
		unless @@ENDPOINTS['text_raw'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'raw text extraction for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['text_raw'][flavor], options)
	end


	# Extracts the title for a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/text-extraction/ 
	# For the docs, please refer to: http://www.alchemyapi.com/api/text-extraction/
	#
	# INPUT:
	# flavor -> which version of the call, i.e. text, url or html.
	# data -> the data to analyze, either the text, the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	# 
	# Available Options:
	# useMetadata -> utilize title info embedded in meta data, 0: disabled, 1: enabled (default) 

	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def title(flavor, data, options = {})
		unless @@ENDPOINTS['title'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'title extraction for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['title'][flavor], options)
	end


	# Parses the microformats for a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/microformats-parsing/
	# For the docs, please refer to: http://www.alchemyapi.com/api/microformats-parsing/
	#
	# INPUT:
	# flavor -> which version of the call, i.e.  url or html.
	# data -> the data to analyze, either the the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# none
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def microformats(flavor, data, options = {})
		unless @@ENDPOINTS['microformats'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'microformats parsing for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['microformats'][flavor], options)
	end


	# Detects the RSS/ATOM feeds for a URL or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/feed-detection/ 
	# For the docs, please refer to: http://www.alchemyapi.com/api/feed-detection/
	# 
	# INPUT:
	# flavor -> which version of the call, i.e.  url or html.
	# data -> the data to analyze, either the the url or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# none
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def feeds(flavor, data, options = {})
		unless @@ENDPOINTS['feeds'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'feed detection for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['feeds'][flavor], options)
	end


	# Categorizes the text for a URL, text or HTML.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/text-categorization/
	# For the docs, please refer to: http://www.alchemyapi.com/api/taxonomy/
	# 
	# INPUT:
	# flavor -> which version of the call, i.e.  url, text or html.
	# data -> the data to analyze, either the the url, text or html code.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# showSourceText -> 0: disabled (default), 1: enabled.
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def taxonomy(flavor, data, options = {})
		unless @@ENDPOINTS['taxonomy'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'Taxonomy info for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['taxonomy'][flavor], options)
	end


	# Combined call (see options below for available extractions) for a URL or text.
	# 
	# INPUT:
	# flavor -> which version of the call, i.e.  url or text.
	# data -> the data to analyze, either the the url or text.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# extract -> VALUE,VALUE,VALUE,... (possible VALUEs: page-image,entity,keyword,title,author,taxonomy,concept,relation,doc-sentiment)
	# extractMode -> (only applies when 'page-image' VALUE passed to 'extract' option) 
	# 		trust-metadata: less CPU-intensive, less accurate
	# 		always-infer: more CPU-intensive, more accurate
	# disambiguate -> whether to disambiguate detected entities, 0: disabled, 1: enabled (default)
	# linkedData -> whether to include Linked Data content links with disambiguated entities, 0: disabled, 1: enabled (default). disambiguate must be enabled to use this.
	# coreference -> whether to he/she/etc coreferences into detected entities, 0: disabled, 1: enabled (default)
	# quotations -> whether to enable quotations extraction, 0: disabled (default), 1: enabled
	# sentiment -> whether to enable entity-level sentiment analysis, 0: disabled (default), 1: enabled. Requires one additional API transaction if enabled.
	# showSourceText -> 0: disabled (default), 1: enabled.
	# maxRetrieve -> maximum number of named entities to extract (default: 50)
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def combined(flavor, data, options = {})
		unless @@ENDPOINTS['combined'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'Combined data for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['combined'][flavor], options)
	end


	# Extract image from a URL.
	# 
	# INPUT:
	# flavor -> which version of the call, i.e.  url.
	# data -> the data to analyze, i.e. the url.
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# extractMode -> trust-metadata: less CPU-intensive and less accurate, always-infer: more CPU-intensive and more accurate
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def image_extract(flavor, data, options = {})
		unless @@ENDPOINTS['image_extract'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'Image for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		options[flavor] = data
		return analyze(@@ENDPOINTS['image_extract'][flavor], options)
	end


	# Tag image from a URL or raw image data.
	# For an overview, please refer to: http://www.alchemyapi.com/products/features/image-tagging/
	# For the docs, please refer to: http://www.alchemyapi.com/api/image-tagging/
	# 
	# INPUT:
	# flavor -> which version of the call, i.e.  url or image.
	# data -> the data to analyze, the url
	# options -> various parameters that can be used to adjust how the API works, see below for more info on the available options.
	#
	# Available Options:
	# extractMode -> trust-metadata: less CPU-intensive and less accurate, always-infer: more CPU-intensive and more accurate
	# (image flavor only)
	# imagePostMode -> how you will post the image
	#  		raw: pass an unencoded image file using POST
	#
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	#
	def image_tag(flavor, data, options = {}, image = '')
		unless @@ENDPOINTS['image_tag'].key?(flavor)
			return { 'status'=>'ERROR', 'statusInfo'=>'Image tagging for ' + flavor + ' not available' }
		end

		#Add the URL encoded data to the options and analyze
		unless data.empty?
			options[flavor] = data
		end
		return analyze_image(@@ENDPOINTS['image_tag'][flavor], options, image)
	end


	private

	# HTTP Request wrapper that is called by the endpoint functions. This function is not intended to be called through an external interface. 
	# It makes the call, then converts the returned JSON string into a Ruby object. 
	#
	# INPUT:
	# url -> the full URI encoded url
	# 
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	# 
	def analyze(url, options)

		#Insert the base URL
		url = @@BASE_URL + url

		#Add the API key and set the output mode to JSON
		options['apikey'] = @apiKey
		options['outputMode'] = 'json'

		uri = URI.parse(url)
		request = Net::HTTP::Post.new(uri.request_uri)
		request.set_form_data(options)

		# disable gzip encoding which blows up in Zlib due to Ruby 2.0 bug
		# otherwise you'll get Zlib::BufError: buffer error
		request['Accept-Encoding'] = 'identity'

		#Fire off the HTTP request
		res = Net::HTTP.start(uri.host, uri.port) do |http|
      		http.request(request)
    	end

		#parse and return the response
		return JSON.parse(res.body)
	end

	# HTTP Request wrapper that is called by the endpoint functions. This function is not intended to be called through an external interface. 
	# It makes the call, then converts the returned JSON string into a Ruby object. 
	#
	# INPUT:
	# url -> the full URI encoded url
	# body -> the raw binary image data
	# 
	# OUTPUT:
	# The response, already converted from JSON to a Ruby object. 
	# 
	def analyze_image(url, options, body)

		#Insert the base URL
		url = @@BASE_URL + url

		#Add the API key and set the output mode to JSON
		options['apikey'] = @apiKey
		options['outputMode'] = 'json'

		url += '?'
		options.each { |h,v|
			url += h + '=' + v + '&'
		}

		#Parse URL
		uri = URI.parse(url)

		request = Net::HTTP::Post.new(uri.request_uri)
		request.body = body.to_s

		# disable gzip encoding which blows up in Zlib due to Ruby 2.0 bug
		# otherwise you'll get Zlib::BufError: buffer error
		request['Accept-Encoding'] = 'identity'

		#Fire off the HTTP request
		res = Net::HTTP.start(uri.host, uri.port) do |http|
			http.request(request)
		end
		
		#parse and return the response
		return JSON.parse(res.body)
	end
end



# Writes the API key to api_key.txt file. It will create the file if it doesn't exist.
# This function is intended to be called from the Python command line using: python -c 'import alchemyapi;alchemyapi.setkey("API_KEY");'
# If you don't have an API key yet, register for one at: http://www.alchemyapi.com/api/register.html
# 
# INPUT:
# key -> Your API key from  Should be 40 hex characters
# 
# OUTPUT:
# none
#

if __FILE__==$0
  	# this will only run if the script was the main, not load'd or require'd
	if ARGV.length == 1
		if (ARGV[0].length == 40)
			puts 'Key: ' + ARGV[0] + ' was written to api_key.txt'
			puts 'You are now ready to start using AlchemyAPI. For an example, run: ruby example.rb'
			File.open('api_key.txt','w') {|f| f.write(ARGV[0]) }
		else
			puts 'The key appears to invalid. Please make sure to use the 40 character key assigned by AlchemyAPI'
		end
	end

end