Use Popen module for non-deadlocking reading of IOuse-popen-module-for-open3

The Gitlab::Popen module reads from standard out and standard error in
a way that avoids deadlocks, and can be used as a substitute for open3.

2 files changed, 13 insertions, 13 deletions

diff --git a/app/models/ssh_host_key.rb b/app/models/ssh_host_key.rb
index b6fb39ee81f..4abc7b01a30 100644
--- a/app/models/ssh_host_key.rb
+++ b/app/models/ssh_host_key.rb
@@ -89,21 +89,17 @@ class SshHostKey
   end
 
   def calculate_reactive_cache
-    known_hosts, errors, status =
-      Open3.popen3({}, *%W[ssh-keyscan -T 5 -p #{url.port} -f-]) do |stdin, stdout, stderr, wait_thr|
-        stdin.puts(url.host)
-        stdin.close
-
-        [
-          cleanup(stdout.read),
-          cleanup(stderr.read),
-          wait_thr.value
-        ]
-      end
+    result = Gitlab::Popen.popen_with_detail(%W[ssh-keyscan -T 5 -p #{url.port} -f-]) do |stdin|
+      stdin.puts(url.host)
+    end
+
+    known_hosts = cleanup(result.stdout)
+    errors = cleanup(result.stderr)
+    status = result.status
 
     # ssh-keyscan returns an exit code 0 in several error conditions, such as an
     # unknown hostname, so check both STDERR and the exit code
-    if status.success? && !errors.present?
+    if status&.success? && !errors.present?
       { known_hosts: known_hosts }
     else
       Rails.logger.debug("Failed to detect SSH host keys for #{id}: #{errors}")
diff --git a/spec/models/ssh_host_key_spec.rb b/spec/models/ssh_host_key_spec.rb
index 4c677569561..5bb84f4a81f 100644
--- a/spec/models/ssh_host_key_spec.rb
+++ b/spec/models/ssh_host_key_spec.rb
@@ -40,8 +40,12 @@ describe SshHostKey do
     stdout = double(:stdout, read: stdout)
     stderr = double(:stderr, read: stderr)
     wait_thr = double(:wait_thr, value: double(success?: status))
+    path = Dir.pwd
+    vars = { 'PWD' => path }
+    cmd = ['ssh-keyscan'].concat(args)
+    options = { chdir: path }
 
-    expect(Open3).to receive(:popen3).with({}, 'ssh-keyscan', *args).and_yield(stdin, stdout, stderr, wait_thr)
+    expect(Open3).to receive(:popen3).with(vars, *cmd, options).and_yield(stdin, stdout, stderr, wait_thr)
 
     stdin
   end