http: automatically follow redirects.

* Automatically follow redirects (up to 5, return a synthetic 598 error after that).
* Add `put` and `timeout` methods.
* Add tests.

app/logical/danbooru/http.rb

@@ -1,17 +1,22 @@
 module Danbooru
   class Http
     DEFAULT_TIMEOUT = 3
+    MAX_REDIRECTS = 5
 
     attr_writer :cache, :http
 
     class << self
-      delegate :get, :post, :delete, :cache, :auth, :basic_auth, :headers, to: :new
+      delegate :get, :put, :post, :delete, :cache, :timeout, :auth, :basic_auth, :headers, to: :new
     end
 
     def get(url, **options)
       request(:get, url, **options)
     end
 
+    def put(url, **options)
+      request(:get, url, **options)
+    end
+
     def post(url, **options)
       request(:post, url, **options)
     end
@@ -24,6 +29,10 @@ module Danbooru
       dup.tap { |o| o.cache = expiry.to_i }
     end
 
+    def timeout(*args)
+      dup.tap { |o| o.http = o.http.timeout(*args) }
+    end
+
     def auth(*args)
       dup.tap { |o| o.http = o.http.auth(*args) }
     end
@@ -44,9 +53,11 @@ module Danbooru
       else
         raw_request(method, url, **options)
       end
+    rescue HTTP::Redirector::TooManyRedirectsError
+      ::HTTP::Response.new(status: 598, body: "", version: "1.1")
     rescue HTTP::TimeoutError
       # return a synthetic http error on connection timeouts
-      ::HTTP::Response.new(status: 522, body: "", version: "1.1")
+      ::HTTP::Response.new(status: 599, body: "", version: "1.1")
     end
 
     def cached_request(method, url, **options)
@@ -65,7 +76,12 @@ module Danbooru
     end
 
     def http
-      @http ||= ::HTTP.timeout(DEFAULT_TIMEOUT).use(:auto_inflate).headers(Danbooru.config.http_headers).headers("Accept-Encoding" => "gzip")
+      @http ||= ::HTTP.
+        follow(max_hops: MAX_REDIRECTS).
+        timeout(DEFAULT_TIMEOUT).
+        use(:auto_inflate).
+        headers(Danbooru.config.http_headers).
+        headers("Accept-Encoding" => "gzip")
     end
   end
 end

test/unit/danbooru_http_test.rb

@@ -0,0 +1,49 @@
+require 'test_helper'
+
+class DanbooruHttpTest < ActiveSupport::TestCase
+  context "Danbooru::Http" do
+    context "#get method" do
+      should "work for all basic methods" do
+        %i[get put post delete].each do |method|
+          response = Danbooru::Http.send(method, "https://httpbin.org/status/200")
+          assert_equal(200, response.status)
+        end
+      end
+
+      should "follow redirects" do
+        response = Danbooru::Http.get("https://httpbin.org/absolute-redirect/3")
+        assert_equal(200, response.status)
+      end
+
+      should "fail if redirected too many times" do
+        response = Danbooru::Http.get("https://httpbin.org/absolute-redirect/10")
+        assert_equal(598, response.status)
+      end
+
+      should "fail if the request takes too long to connect" do
+        response = Danbooru::Http.timeout(1).get("https://httpbin.org/delay/5")
+        assert_equal(599, response.status)
+      end
+
+      should "fail if the request takes too long to download" do
+        response = Danbooru::Http.timeout(1).get("https://httpbin.org/drip?duration=5&numbytes=5")
+        assert_equal(599, response.status)
+      end
+
+      should "automatically decompress gzipped responses" do
+        response = Danbooru::Http.get("https://httpbin.org/gzip")
+        assert_equal(200, response.status)
+        assert_equal(true, response.parse["gzipped"])
+      end
+
+      should "cache requests" do
+        response1 = Danbooru::Http.cache(1.minute).get("https://httpbin.org/uuid")
+        assert_equal(200, response1.status)
+
+        response2 = Danbooru::Http.cache(1.minute).get("https://httpbin.org/uuid")
+        assert_equal(200, response2.status)
+        assert_equal(response2.body, response1.body)
+      end
+    end
+  end
+end