implement check_dependencies!

lib/kamal/secrets/adapters/aws_secrets_manager.rb

@@ -22,4 +22,13 @@ class Kamal::Secrets::Adapters::AwsSecretsManager < Kamal::Secrets::Adapters::Ba
         raise RuntimeError, "Could not read #{secret} from AWS Secrets Manager" unless $?.success?
       end
     end
+
+    def check_dependencies!
+      raise RuntimeError, "AWS CLI is not installed" unless cli_installed?
+    end
+
+    def cli_installed?
+      `aws --version 2> /dev/null`
+      $?.success?
+    end
 end

test/secrets/aws_secrets_manager_adapter_test.rb

@@ -2,6 +2,7 @@ require "test_helper"
 
 class AwsSecretsManagerAdapterTest < SecretAdapterTestCase
   test "fetch" do
+    stub_ticks.with("aws --version 2> /dev/null")
     stub_ticks
       .with("aws secretsmanager batch-get-secret-value --secret-id-list secret/KEY1 secret/KEY2 secret2/KEY3 --profile default")
       .returns(<<~JSON)
@@ -44,6 +45,7 @@ class AwsSecretsManagerAdapterTest < SecretAdapterTestCase
   end
 
   test "fetch with secret names" do
+    stub_ticks.with("aws --version 2> /dev/null")
     stub_ticks
       .with("aws secretsmanager batch-get-secret-value --secret-id-list secret/KEY1 secret/KEY2 --profile default")
       .returns(<<~JSON)
@@ -74,6 +76,15 @@ class AwsSecretsManagerAdapterTest < SecretAdapterTestCase
     assert_equal expected_json, json
   end
 
+  test "fetch without CLI installed" do
+    stub_ticks_with("aws --version 2> /dev/null", succeed: false)
+
+    error = assert_raises RuntimeError do
+      JSON.parse(shellunescape(run_command("fetch", "SECRET1")))
+    end
+    assert_equal "AWS CLI is not installed", error.message
+  end
+
   private
     def run_command(*command)
       stdouted do