Respect proxy exceptions

Our usage of Faraday in this library is...unusual.

Faraday does generally respect the proxy & proxy exception settings when
you pass the URL directly to a `conn.post` method or anything like that,
but since we set the URL within this block, that's after Faraday's logic
has decided what the proxy should be, and since at that point Faraday
didn't know what URL we were requesting, it used the default proxy
details.

Author: wfleming

lib/cc/service/http.rb

@@ -58,7 +58,10 @@ def http_method(method, url = nil, body = nil, headers = nil)
       CC::Service::SafeWebhook.ensure_safe!(url)
 
       http.send(method) do |req|
-        req.url(url) if url
+        if url
+          req.url(url)
+          req.options.proxy = http.proxy_from_env(url)
+        end
         req.headers.update(headers) if headers
         req.body = body if body
         block.call req if block

spec/cc/service_spec.rb

@@ -75,4 +75,54 @@
 
     expect(services.include?(CC::PullRequests)).not_to eq(true)
   end
+
+  context "with proxy details" do
+    before do
+      @old_no_proxy = ENV["no_proxy"]
+      @old_http_proxy = ENV["http_proxy"]
+      ENV["no_proxy"] = "github.com"
+      ENV["http_proxy"] = "http://127.0.0.2:42"
+    end
+
+    after do
+      ENV["no_proxy"] = @old_no_proxy
+      ENV["http_proxy"] = @old_http_proxy
+    end
+
+    it "uses the proxy when it should" do
+      stub_http("http://proxied.test/my/test/url") do |env|
+        expect(env.request.proxy).to be_instance_of(Faraday::ProxyOptions)
+        expect(env.request.proxy.uri).to eq(URI.parse("http://127.0.0.2:42"))
+        [200, {}, '{"ok": true, "thing": "123"}']
+      end
+
+      response = service_post("http://proxied.test/my/test/url", { token: "1234" }.to_json, {}) do |inner_response|
+        body = JSON.parse(inner_response.body)
+        { thing: body["thing"] }
+      end
+
+      expect(response[:ok]).to eq(true)
+      expect(response[:params]).to eq('{"token":"1234"}')
+      expect(response[:endpoint_url]).to eq("http://proxied.test/my/test/url")
+      expect(response[:status]).to eq(200)
+    end
+
+    it "respects proxy exclusions" do
+      stub_http("http://github.com/my/test/url") do |env|
+        expect(env.request.proxy).to be_nil
+        [200, {}, '{"ok": true, "thing": "123"}']
+      end
+
+      response = service_post("http://github.com/my/test/url", { token: "1234" }.to_json, {}) do |inner_response|
+        body = JSON.parse(inner_response.body)
+        { thing: body["thing"] }
+      end
+
+      expect(response[:ok]).to eq(true)
+      expect(response[:params]).to eq('{"token":"1234"}')
+      expect(response[:endpoint_url]).to eq("http://github.com/my/test/url")
+      expect(response[:status]).to eq(200)
+    end
+
+  end
 end