From 91aae4d755504518258c9b4c9aae8baa4eabc2dc Mon Sep 17 00:00:00 2001
From: Benjamin Neff <benjamin@coding4coffee.ch>
Date: Sun, 28 Apr 2019 11:33:56 +0200
Subject: [PATCH] Fix 500er when calling protocol handler with invalid URL

---
 app/services/diaspora_link_service.rb       | 10 ++++++----
 spec/services/diaspora_link_service_spec.rb | 12 ++++++++++++
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/app/services/diaspora_link_service.rb b/app/services/diaspora_link_service.rb
index 1923aa01d..a8ab51420 100644
--- a/app/services/diaspora_link_service.rb
+++ b/app/services/diaspora_link_service.rb
@@ -10,7 +10,9 @@ class DiasporaLinkService
   end
 
   def find_or_fetch_entity
-    entity_finder.find || fetch_entity
+    if type && guid
+      entity_finder.find || fetch_entity
+    end
   end
 
   private
@@ -38,8 +40,8 @@ class DiasporaLinkService
   def parse
     normalize
     match = DiasporaFederation::Federation::DiasporaUrlParser::DIASPORA_URL_REGEX.match(link)
-    @author = match[1]
-    @type = match[2]
-    @guid = match[3]
+    if match
+      @author, @type, @guid = match.captures
+    end
   end
 end
diff --git a/spec/services/diaspora_link_service_spec.rb b/spec/services/diaspora_link_service_spec.rb
index bde411a27..fd3f6e6b3 100644
--- a/spec/services/diaspora_link_service_spec.rb
+++ b/spec/services/diaspora_link_service_spec.rb
@@ -40,5 +40,17 @@ describe DiasporaLinkService do
         expect(service.find_or_fetch_entity).to be_nil
       end
     end
+
+    context "with invalid links" do
+      it "returns nil when the link is invalid" do
+        service = described_class.new("web+diaspora://something_invalid")
+        expect(service.find_or_fetch_entity).to be_nil
+      end
+
+      it "returns nil when the author is valid, but rest of the link is invalid" do
+        service = described_class.new("web+diaspora://#{alice.diaspora_handle}/foo/bar")
+        expect(service.find_or_fetch_entity).to be_nil
+      end
+    end
   end
 end