lib/infoboxer/media_wiki.rb
# frozen_string_literal: true
require 'mediawiktory'
require 'addressable/uri'
require_relative 'media_wiki/traits'
require_relative 'media_wiki/page'
module Infoboxer
# MediaWiki client class.
#
# Usage:
#
# ```ruby
# client = Infoboxer::MediaWiki
# .new('http://en.wikipedia.org/w/api.php', user_agent: 'My Own Project')
# page = client.get('Argentina')
# ```
#
# Consider using shortcuts like {Infoboxer.wiki}, {Infoboxer.wikipedia},
# {Infoboxer.wp} and so on instead of direct instation of this class
# (although you can if you want to!)
#
class MediaWiki
# Default Infoboxer User-Agent header.
#
# You can set yours as an option to {Infoboxer.wiki} and its shortcuts,
# or to {#initialize}
UA = "Infoboxer/#{Infoboxer::VERSION} "\
'(https://github.com/molybdenum-99/infoboxer; zverok.offline@gmail.com)'
class << self
# User agent getter/setter.
#
# Default value is {UA}.
#
# You can also use per-instance option, see {#initialize}
#
# @return [String]
attr_accessor :user_agent
end
# @private
attr_reader :api_base_url, :traits
# @return [MediaWiktory::Wikipedia::Client]
attr_reader :api
# Creating new MediaWiki client. {Infoboxer.wiki} provides shortcut
# for it, as well as shortcuts for some well-known wikis, like
# {Infoboxer.wikipedia}.
#
# @param api_base_url [String] URL of `api.php` file in your MediaWiki
# installation. Typically, its `<domain>/w/api.php`, but can vary
# in different wikis.
# @param user_agent [String] (also aliased as `:ua`) Custom User-Agent header.
def initialize(api_base_url, ua: nil, user_agent: ua)
@api_base_url = Addressable::URI.parse(api_base_url)
@api = MediaWiktory::Wikipedia::Api.new(api_base_url, user_agent: user_agent(user_agent))
@traits = Traits.get(@api_base_url.host, siteinfo)
end
# Receive "raw" data from Wikipedia (without parsing or wrapping in
# classes).
#
# @param titles [Array<String>] List of page titles to get.
# @param processor [Proc] Optional block to preprocess MediaWiktory query. Refer to
# [MediaWiktory::Actions::Query](http://www.rubydoc.info/gems/mediawiktory/MediaWiktory/Wikipedia/Actions/Query)
# for its API. Infoboxer assumes that the block returns new instance of `Query`, so be careful
# while using it.
#
# @return [Hash{String => Hash}] Hash of `{requested title => raw MediaWiki object}`. Note that
# even missing (does not exist in current Wiki) or invalid (impossible title) still be present
# in response, just will have `"missing"` or `"invalid"` key, just like MediaWiki returns them.
def raw(*titles, &processor)
# could emerge on "automatically" created page lists, should work
return {} if titles.empty?
titles.each_slice(50).map do |part|
request = prepare_request(@api.query.titles(*part), &processor)
response = request.response
# If additional props are required, there may be additional pages, even despite each_slice(50)
response = response.continue while response.continue?
sources = response['pages'].values.map { |page| [page['title'], page] }.to_h
redirects =
if response['redirects']
response['redirects'].map { |r| [r['from'], sources[r['to']]] }.to_h
else
{}
end
# This way for 'Einstein' query we'll have {'Albert Einstein' => page, 'Einstein' => same page}
sources.merge(redirects)
end.inject(:merge)
end
# Receive list of parsed MediaWiki pages for list of titles provided.
# All pages are received with single query to MediaWiki API.
#
# **NB**: if you are requesting more than 50 titles at once
# (MediaWiki limitation for single request), Infoboxer will do as
# many queries as necessary to extract them all (it will be like
# `(titles.count / 50.0).ceil` requests)
#
# @param titles [Array<String>] List of page titles to get.
# @param interwiki [Symbol] Identifier of other wiki, related to current, to fetch pages from.
# @param processor [Proc] Optional block to preprocess MediaWiktory query. Refer to
# [MediaWiktory::Actions::Query](http://www.rubydoc.info/gems/mediawiktory/MediaWiktory/Wikipedia/Actions/Query)
# for its API. Infoboxer assumes that the block returns new instance of `Query`, so be careful
# while using it.
#
# @return [Page, Tree::Nodes<Page>] array of parsed pages. Notes:
# * if you call `get` with only one title, one page will be
# returned instead of an array
# * if some of pages are not in wiki, they will not be returned,
# therefore resulting array can be shorter than titles array;
# you can always check `pages.map(&:title)` to see what you've
# really received; this approach allows you to write absent-minded
# code like this:
#
# ```ruby
# Infoboxer.wp.get('Argentina', 'Chile', 'Something non-existing').
# infobox.fetch('some value')
# ```
# and obtain meaningful results instead of `NoMethodError` or
# `SomethingNotFound`.
#
def get(*titles, interwiki: nil, &processor)
return interwikis(interwiki).get(*titles, &processor) if interwiki
pages = get_h(*titles, &processor).values.compact
titles.count == 1 ? pages.first : Tree::Nodes[*pages]
end
# Same as {#get}, but returns hash of `{requested title => page}`.
#
# Useful quirks:
# * when requested page not existing, key will be still present in
# resulting hash (value will be `nil`);
# * when requested page redirects to another, key will still be the
# requested title. For ex., `get_h('Einstein')` will return hash
# with key 'Einstein' and page titled 'Albert Einstein'.
#
# This allows you to be in full control of what pages of large list
# you've received.
#
# @param titles [Array<String>] List of page titles to get.
# @param processor [Proc] Optional block to preprocess MediaWiktory query. Refer to
# [MediaWiktory::Actions::Query](http://www.rubydoc.info/gems/mediawiktory/MediaWiktory/Wikipedia/Actions/Query)
# for its API. Infoboxer assumes that the block returns new instance of `Query`, so be careful
# while using it.
#
# @return [Hash<String, Page>]
#
def get_h(*titles, &processor)
raw_pages = raw(*titles, &processor)
.tap { |ps| ps.detect { |_, p| p['invalid'] }.tap { |_, i| i && fail(i['invalidreason']) } }
.reject { |_, p| p.key?('missing') }
titles.map { |title| [title, make_page(raw_pages, title)] }.to_h
end
# Receive list of parsed MediaWiki pages from specified category.
#
# @param title [String] Category title. You can use namespaceless title (like
# `"Countries in South America"`), title with namespace (like
# `"Category:Countries in South America"`) or title with local
# namespace (like `"Catégorie:Argentine"` for French Wikipedia)
# @param limit [Integer, "max"]
# @param processor [Proc] Optional block to preprocess MediaWiktory query. Refer to
# [MediaWiktory::Actions::Query](http://www.rubydoc.info/gems/mediawiktory/MediaWiktory/Wikipedia/Actions/Query)
# for its API. Infoboxer assumes that the block returns new instance of `Query`, so be careful
# while using it.
#
# @return [Tree::Nodes<Page>] array of parsed pages.
#
def category(title, limit: 'max', &processor)
title = normalize_category_title(title)
list(@api.query.generator(:categorymembers).title(title), limit, &processor)
end
# Receive list of parsed MediaWiki pages for provided search query.
# See [MediaWiki API docs](https://www.mediawiki.org/w/api.php?action=help&modules=query%2Bsearch)
# for details.
#
# @param query [String] Search query. For old installations, look at
# https://www.mediawiki.org/wiki/Help:Searching
# for search syntax. For new ones (including Wikipedia), see at
# https://www.mediawiki.org/wiki/Help:CirrusSearch.
# @param limit [Integer, "max"]
# @param processor [Proc] Optional block to preprocess MediaWiktory query. Refer to
# [MediaWiktory::Actions::Query](http://www.rubydoc.info/gems/mediawiktory/MediaWiktory/Wikipedia/Actions/Query)
# for its API. Infoboxer assumes that the block returns new instance of `Query`, so be careful
# while using it.
#
# @return [Tree::Nodes<Page>] array of parsed pages.
#
def search(query, limit: 'max', &processor)
list(@api.query.generator(:search).search(query), limit, &processor)
end
# Receive list of parsed MediaWiki pages with titles startin from prefix.
# See [MediaWiki API docs](https://www.mediawiki.org/w/api.php?action=help&modules=query%2Bprefixsearch)
# for details.
#
# @param prefix [String] Page title prefix.
# @param limit [Integer, "max"]
# @param processor [Proc] Optional block to preprocess MediaWiktory query. Refer to
# [MediaWiktory::Actions::Query](http://www.rubydoc.info/gems/mediawiktory/MediaWiktory/Wikipedia/Actions/Query)
# for its API. Infoboxer assumes that the block returns new instance of `Query`, so be careful
# while using it.
#
# @return [Tree::Nodes<Page>] array of parsed pages.
#
def prefixsearch(prefix, limit: 'max', &processor)
list(@api.query.generator(:prefixsearch).search(prefix), limit, &processor)
end
# @return [String]
def inspect
"#<#{self.class}(#{@api_base_url.host})>"
end
private
def make_page(raw_pages, title)
_, source = raw_pages.detect { |ptitle, _| ptitle.casecmp(title).zero? }
source or return nil
Page.new(self, Parser.paragraphs(source['revisions'].first['*'], traits), source)
end
def list(query, limit, &processor)
request = prepare_request(query.limit(limit), &processor)
response = request.response
response = response.continue while response.continue? && (limit == 'max' || response['pages'].count < limit)
return Tree::Nodes[] if response['pages'].nil?
pages = response['pages']
.values.select { |p| p['missing'].nil? }
.map { |raw| Page.new(self, Parser.paragraphs(raw['revisions'].first['*'], traits), raw) }
Tree::Nodes[*pages]
end
def prepare_request(request)
request = request.prop(:revisions, :info).prop(:content, :timestamp, :url).redirects
block_given? ? yield(request) : request
end
def normalize_category_title(title)
# FIXME: shouldn't it go to MediaWiktory?..
namespace, titl = title.include?(':') ? title.split(':', 2) : [nil, title]
namespace, titl = nil, title unless traits.category_namespace.include?(namespace)
namespace ||= traits.category_namespace.first
[namespace, titl].join(':')
end
def user_agent(custom)
custom || self.class.user_agent || UA
end
def siteinfo
@siteinfo ||= @api.query.meta(:siteinfo).prop(:namespaces, :namespacealiases, :interwikimap).response.to_h
end
def interwikis(prefix)
@interwikis ||= Hash.new { |h, pre|
interwiki = siteinfo['interwikimap'].detect { |iw| iw['prefix'] == prefix } or
fail ArgumentError, "Undefined interwiki: #{prefix}"
# FIXME: fragile, but what can we do?..
m = interwiki['url'].match(%r{^(.+)/wiki/\$1$}) or
fail ArgumentError, "Interwiki #{interwiki} seems not to be a MediaWiki instance"
h[pre] = self.class.new("#{m[1]}/w/api.php") # TODO: copy useragent
}
@interwikis[prefix]
end
end
end