Close http connection in perform method of Request class (#6889)

HTTP connections must be explicitly closed in many cases, and letting
perform method close connections makes its callers less redundant and
prevent them from forgetting to close connections.

app/lib/provider_discovery.rb

@@ -13,15 +13,14 @@ class ProviderDiscovery < OEmbed::ProviderDiscovery
     def discover_provider(url, **options)
       format = options[:format]
 
-      if options[:html]
-        html = Nokogiri::HTML(options[:html])
-      else
-        res = Request.new(:get, url).perform
-
-        raise OEmbed::NotFound, url if res.code != 200 || res.mime_type != 'text/html'
-
-        html = Nokogiri::HTML(res.to_s)
-      end
+      html = if options[:html]
+               Nokogiri::HTML(options[:html])
+             else
+               Request.new(:get, url).perform do |res|
+                 raise OEmbed::NotFound, url if res.code != 200 || res.mime_type != 'text/html'
+                 Nokogiri::HTML(res.to_s)
+               end
+             end
 
       if format.nil? || format == :json
         provider_endpoint ||= html.at_xpath('//link[@type="application/json+oembed"]')&.attribute('href')&.value

app/lib/request.rb

@@ -33,9 +33,17 @@ class Request
   end
 
   def perform
-    http_client.headers(headers).public_send(@verb, @url.to_s, @options)
-  rescue => e
-    raise e.class, "#{e.message} on #{@url}", e.backtrace[0]
+    begin
+      response = http_client.headers(headers).public_send(@verb, @url.to_s, @options)
+    rescue => e
+      raise e.class, "#{e.message} on #{@url}", e.backtrace[0]
+    end
+
+    begin
+      yield response
+    ensure
+      http_client.close
+    end
   end
 
   def headers
@@ -88,7 +96,7 @@ class Request
   end
 
   def http_client
-    HTTP.timeout(:per_operation, timeout).follow(max_hops: 2)
+    @http_client ||= HTTP.timeout(:per_operation, timeout).follow(max_hops: 2)
   end
 
   class Socket < TCPSocket