Run pre-connect hooks before ssh commands

We hook into the SSHKit `on` method to run the pre-connect hook before
the first SSH command. This doesn't work for interactive exec commands
where ssh is called directly.

Fixes: https://github.com/basecamp/kamal/issues/1157

lib/kamal/cli/accessory.rb

@@ -141,6 +141,8 @@ class Kamal::Cli::Accessory < Kamal::Cli::Base
   option :interactive, aliases: "-i", type: :boolean, default: false, desc: "Execute command over ssh for an interactive shell (use for console/bash)"
   option :reuse, type: :boolean, default: false, desc: "Reuse currently running container instead of starting a new one"
   def exec(name, *cmd)
+    pre_connect_if_required
+
     cmd = Kamal::Utils.join_commands(cmd)
     with_accessory(name) do |accessory, hosts|
       case

lib/kamal/cli/app.rb

@@ -106,6 +106,8 @@ class Kamal::Cli::App < Kamal::Cli::Base
   option :env, aliases: "-e", type: :hash, desc: "Set environment variables for the command"
   option :detach, type: :boolean, default: false, desc: "Execute command in a detached container"
   def exec(*cmd)
+    pre_connect_if_required
+
     if (incompatible_options = [ :interactive, :reuse ].select { |key| options[:detach] && options[key] }.presence)
       raise ArgumentError, "Detach is not compatible with #{incompatible_options.join(" or ")}"
     end

lib/kamal/cli/base.rb

@@ -147,12 +147,16 @@ module Kamal::Cli
       end
 
       def on(*args, &block)
+        pre_connect_if_required
+
+        super
+      end
+
+      def pre_connect_if_required
         if !KAMAL.connected?
           run_hook "pre-connect"
           KAMAL.connected = true
         end
-
-        super
       end
 
       def command

lib/kamal/cli/server.rb

@@ -2,6 +2,8 @@ class Kamal::Cli::Server < Kamal::Cli::Base
   desc "exec", "Run a custom command on the server (use --help to show options)"
   option :interactive, type: :boolean, aliases: "-i", default: false, desc: "Run the command interactively (use for console/bash)"
   def exec(*cmd)
+    pre_connect_if_required
+
     cmd = Kamal::Utils.join_commands(cmd)
     hosts = KAMAL.hosts
 

test/cli/app_test.rb

@@ -334,18 +334,24 @@ class CliAppTest < CliTestCase
   end
 
   test "exec interactive" do
+    Kamal::Commands::Hook.any_instance.stubs(:hook_exists?).returns(true)
     SSHKit::Backend::Abstract.any_instance.expects(:exec)
       .with("ssh -t root@1.1.1.1 -p 22 'docker run -it --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size=\"10m\" dhh/app:latest ruby -v'")
+
     run_command("exec", "-i", "ruby -v").tap do |output|
+      assert_hook_ran "pre-connect", 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
+    Kamal::Commands::Hook.any_instance.stubs(:hook_exists?).returns(true)
     SSHKit::Backend::Abstract.any_instance.expects(:exec)
       .with("ssh -t root@1.1.1.1 -p 22 'docker exec -it app-web-999 ruby -v'")
+
     run_command("exec", "-i", "--reuse", "ruby -v").tap do |output|
+      assert_hook_ran "pre-connect", output
       assert_match "Get current version of running container...", output
       assert_match "Running /usr/bin/env sh -c 'docker ps --latest --format '\\''{{.Names}}'\\'' --filter label=service=app --filter label=destination= --filter label=role=web --filter status=running --filter status=restarting --filter ancestor=$(docker image ls --filter reference=dhh/app:latest --format '\\''{{.ID}}'\\'') ; docker ps --latest --format '\\''{{.Names}}'\\'' --filter label=service=app --filter label=destination= --filter label=role=web --filter status=running --filter status=restarting' | head -1 | 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