Allow setting the build context used for building

lib/mrsk/commands/builder/base.rb

@@ -12,6 +12,9 @@ class Mrsk::Commands::Builder::Base < Mrsk::Commands::Base
   def build_options
     [ *build_tags, *build_labels, *build_args, *build_secrets, *build_dockerfile ]
   end
+
+  def build_context
+    context
   end
 
   private
@@ -46,4 +49,8 @@ class Mrsk::Commands::Builder::Base < Mrsk::Commands::Base
     def dockerfile
       (config.builder && config.builder["dockerfile"]) || "Dockerfile"
     end
+
+    def context
+      (config.builder && config.builder["context"]) || "."
+    end
 end

lib/mrsk/commands/builder/multiarch.rb

@@ -13,7 +13,7 @@ class Mrsk::Commands::Builder::Multiarch < Mrsk::Commands::Builder::Base
       "--platform", "linux/amd64,linux/arm64",
       "--builder", builder_name,
       *build_options,
-      "."
+      build_context
   end
 
   def info

lib/mrsk/commands/builder/native.rb

@@ -9,7 +9,7 @@ class Mrsk::Commands::Builder::Native < Mrsk::Commands::Builder::Base
 
   def push
     combine \
-      docker(:build, *build_options, "."),
+      docker(:build, *build_options, build_context),
       docker(:push, config.absolute_image)
   end
 

lib/mrsk/commands/builder/native/remote.rb

@@ -17,7 +17,7 @@ class Mrsk::Commands::Builder::Native::Remote < Mrsk::Commands::Builder::Native
       "--platform", platform,
       "--builder", builder_name,
       *build_options,
-      "."
+      build_context
   end
 
   def info

test/commands/builder_test.rb

@@ -58,6 +58,13 @@ class CommandsBuilderTest < ActiveSupport::TestCase
       builder.target.build_options.join(" ")
   end
 
+  test "build context" do
+    builder = new_builder_command(builder: { "context" => ".." })
+    assert_equal \
+      "docker buildx build --push --platform linux/amd64,linux/arm64 --builder mrsk-app-multiarch -t dhh/app:123 -t dhh/app:latest --label service=\"app\" --file Dockerfile ..",
+      builder.push.join(" ")
+  end
+
   test "native push with build args" do
     builder = new_builder_command(builder: { "multiarch" => false, "args" => { "a" => 1, "b" => 2 } })
     assert_equal \