Run interactive commands with the correct host

Fixes https://github.com/basecamp/kamal/issues/430

lib/kamal/cli/app.rb

@@ -115,14 +115,16 @@ class Kamal::Cli::App < Kamal::Cli::Base
       say "Get current version of running container...", :magenta unless options[:version]
       using_version(options[:version] || current_running_version) do |version|
         say "Launching interactive command with version #{version} via SSH from existing container on #{KAMAL.primary_host}...", :magenta
-        run_locally { exec KAMAL.app(role: "web").execute_in_existing_container_over_ssh(cmd, host: KAMAL.primary_host) }
+        run_locally { exec KAMAL.app(role: KAMAL.primary_role).execute_in_existing_container_over_ssh(cmd, host: KAMAL.primary_host) }
       end
 
     when options[:interactive]
       say "Get most recent version available as an image...", :magenta unless options[:version]
       using_version(version_or_latest) do |version|
         say "Launching interactive command with version #{version} via SSH from new container on #{KAMAL.primary_host}...", :magenta
-        run_locally { exec KAMAL.app(role: KAMAL.roles_on(KAMAL.primary_host).first).execute_in_new_container_over_ssh(cmd, host: KAMAL.primary_host) }
+        run_locally do
+          exec KAMAL.app(role: KAMAL.primary_role).execute_in_new_container_over_ssh(cmd, host: KAMAL.primary_host)
+        end
       end
 
     when options[:reuse]

lib/kamal/commander.rb

@@ -39,6 +39,10 @@ class Kamal::Commander
     specific_hosts&.first || specific_roles&.first&.primary_host || config.primary_web_host
   end
 
+  def primary_role
+    roles_on(primary_host).first
+  end
+
   def roles
     (specific_roles || config.roles).select do |role|
       ((specific_hosts || config.all_hosts) & role.hosts).any?

test/cli/app_test.rb

@@ -170,6 +170,25 @@ class CliAppTest < CliTestCase
     end
   end
 
+  test "exec interactive" do
+    SSHKit::Backend::Abstract.any_instance.expects(:exec)
+      .with("ssh -t root@1.1.1.1 'docker run -it --rm --env-file .kamal/env/roles/app-web.env dhh/app:latest ruby -v'")
+    run_command("exec", "-i", "ruby -v").tap do |output|
+      assert_match "Get most recent version available as an image...", output
+      assert_match "Launching interactive command with version latest via SSH from new container on 1.1.1.1...", output
+    end
+  end
+
+  test "exec interactive with reuse" do
+    SSHKit::Backend::Abstract.any_instance.expects(:exec)
+      .with("ssh -t root@1.1.1.1 'docker exec -it app-web-999 ruby -v'")
+    run_command("exec", "-i", "--reuse", "ruby -v").tap do |output|
+      assert_match "Get current version of running container...", output
+      assert_match "Running docker ps --filter label=service=app --filter label=role=web --filter status=running --filter status=restarting --latest --format \"{{.Names}}\" | while read line; do echo ${line#app-web-}; done on 1.1.1.1", output
+      assert_match "Launching interactive command with version 999 via SSH from existing container on 1.1.1.1...", output
+    end
+  end
+
   test "containers" do
     run_command("containers").tap do |output|
       assert_match "docker container ls --all --filter label=service=app", output

test/commander_test.rb

@@ -49,6 +49,12 @@ class CommanderTest < ActiveSupport::TestCase
     assert_equal "1.1.1.3", @kamal.primary_host
   end
 
+  test "primary_role" do
+    assert_equal "web", @kamal.primary_role
+    @kamal.specific_roles = "workers"
+    assert_equal "workers", @kamal.primary_role
+  end
+
   test "roles_on" do
     assert_equal [ "web" ], @kamal.roles_on("1.1.1.1")
     assert_equal [ "workers" ], @kamal.roles_on("1.1.1.3")