Fix Bitbucket Server importer error handling

The importer would display a 500 error page if you attempted to import
using a non-existent DNS entry. This commit rescues known network issues
and consolidates them into
BitbucketServer::Connection::ConnectionError`.  The previous error
handling in the paginator doesn't work because it returns a lazy
collection.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/56154

2 files changed, 18 insertions, 6 deletions

diff --git a/spec/lib/bitbucket_server/client_spec.rb b/spec/lib/bitbucket_server/client_spec.rb
index 5de0a9a65b5..b021e69800a 100644
--- a/spec/lib/bitbucket_server/client_spec.rb
+++ b/spec/lib/bitbucket_server/client_spec.rb
@@ -17,12 +17,6 @@ describe BitbucketServer::Client do
 
       subject.pull_requests(project, repo_slug)
     end
-
-    it 'throws an exception when connection fails' do
-      allow(BitbucketServer::Collection).to receive(:new).and_raise(OpenSSL::SSL::SSLError)
-
-      expect { subject.pull_requests(project, repo_slug) }.to raise_error(described_class::ServerError)
-    end
   end
 
   describe '#activities' do
diff --git a/spec/lib/bitbucket_server/connection_spec.rb b/spec/lib/bitbucket_server/connection_spec.rb
index b5da4cb1a49..ab8a5b89608 100644
--- a/spec/lib/bitbucket_server/connection_spec.rb
+++ b/spec/lib/bitbucket_server/connection_spec.rb
@@ -26,6 +26,12 @@ describe BitbucketServer::Connection do
 
       expect { subject.get(url) }.to raise_error(described_class::ConnectionError)
     end
+
+    it 'throws an exception upon a network error' do
+      WebMock.stub_request(:get, url).with(headers: { 'Accept' => 'application/json' }).to_raise(OpenSSL::SSL::SSLError)
+
+      expect { subject.get(url) }.to raise_error(described_class::ConnectionError)
+    end
   end
 
   describe '#post' do
@@ -42,6 +48,12 @@ describe BitbucketServer::Connection do
 
       expect { subject.post(url, payload) }.to raise_error(described_class::ConnectionError)
     end
+
+    it 'throws an exception upon a network error' do
+      WebMock.stub_request(:post, url).with(headers: { 'Accept' => 'application/json' }).to_raise(OpenSSL::SSL::SSLError)
+
+      expect { subject.post(url, payload) }.to raise_error(described_class::ConnectionError)
+    end
   end
 
   describe '#delete' do
@@ -63,6 +75,12 @@ describe BitbucketServer::Connection do
 
         expect { subject.delete(:branches, branch_path, payload) }.to raise_error(described_class::ConnectionError)
       end
+
+      it 'throws an exception upon a network error' do
+        WebMock.stub_request(:delete, branch_url).with(headers: headers).to_raise(OpenSSL::SSL::SSLError)
+
+        expect { subject.delete(:branches, branch_path, payload) }.to raise_error(described_class::ConnectionError)
+      end
     end
   end
 end