Add :tar option for releases to create a tarball (#9290)

4 files changed, 100 insertions, 4 deletions

diff --git a/lib/mix/lib/mix/release.ex b/lib/mix/lib/mix/release.ex
index 146273b3f..ce6099354 100644
--- a/lib/mix/lib/mix/release.ex
+++ b/lib/mix/lib/mix/release.ex
@@ -25,7 +25,8 @@ defmodule Mix.Release do
       and `term` is the value given to it on `c:Config.Provider.init/1`
     * `:options` - a keyword list with all other user supplied release options
     * `:steps` - a list of functions that receive the release and returns a release.
-      Must also contain the atom `:assemble` which is the internal assembling step
+      Must also contain the atom `:assemble` which is the internal assembling step.
+      May also contain the atom `:tar` to create a tarball of the release.
 
   """
   defstruct [
@@ -335,12 +336,14 @@ defmodule Mix.Release do
   end
 
   defp validate_steps!(steps) do
-    if not is_list(steps) or Enum.any?(steps, &(&1 != :assemble and not is_function(&1, 1))) do
+    valid_atoms = [:assemble, :tar]
+
+    if not is_list(steps) or Enum.any?(steps, &(&1 not in valid_atoms and not is_function(&1, 1))) do
       Mix.raise("""
         The :steps option must be a list of:
 
         * anonymous function that receives one argument
-        * the atom :assemble
+        * the atom :assemble or :tar
 
       Got: #{inspect(steps)}
       """)
@@ -350,6 +353,14 @@ defmodule Mix.Release do
       Mix.raise("The :steps option must contain the atom :assemble once, got: #{inspect(steps)}")
     end
 
+    if :assemble in Enum.drop_while(steps, &(&1 != :tar)) do
+      Mix.raise("The :tar step must come after :assemble")
+    end
+
+    if Enum.count(steps, &(&1 == :tar)) > 1 do
+      Mix.raise("The :steps option can only contain the atom :tar once")
+    end
+
     :ok
   end
 
diff --git a/lib/mix/lib/mix/tasks/release.ex b/lib/mix/lib/mix/tasks/release.ex
index b555ee500..413872f53 100644
--- a/lib/mix/lib/mix/tasks/release.ex
+++ b/lib/mix/lib/mix/tasks/release.ex
@@ -492,7 +492,9 @@ defmodule Mix.Tasks.Release do
   can pass anonymous functions before and after the `:assemble` to
   customize your release assembling pipeline. Those anonymous functions
   will receive a `Mix.Release` struct and must return the same or
-  an updated `Mix.Release` struct.
+  an updated `Mix.Release` struct. It is also possible to build a tarball
+  of the release by passing the `:tar` step anywhere after `:assemble`.
+  The tarball is created in `_build/MIX_ENV/rel/RELEASE_NAME-RELEASE_VSN.tar.gz`
 
   See `Mix.Release` for more documentation on the struct and which
   fields can be modified. Note that `:steps` field itself can be
@@ -954,6 +956,10 @@ defmodule Mix.Tasks.Release do
     end
   end
 
+  defp run_steps(%{steps: [:tar | steps]} = release) do
+    %{release | steps: steps} |> make_tar() |> run_steps()
+  end
+
   defp run_steps(%{steps: [:assemble | steps]} = release) do
     %{release | steps: steps} |> assemble() |> run_steps()
   end
@@ -1007,6 +1013,34 @@ defmodule Mix.Tasks.Release do
     release
   end
 
+  defp make_tar(release) do
+    tar_filename = "#{release.name}-#{release.version}.tar.gz"
+    out_path = Path.join([release.path, "..", "..", tar_filename]) |> Path.expand()
+    info(release, [:green, "* building ", :reset, out_path])
+
+    lib_dirs =
+      Enum.reduce(release.applications, [], fn {name, app_config}, acc ->
+        vsn = Keyword.fetch!(app_config, :vsn)
+        [Path.join("lib", "#{name}-#{vsn}") | acc]
+      end)
+
+    release_files =
+      for basename <- File.ls!(Path.join(release.path, "releases")),
+          not File.dir?(Path.join([release.path, "releases", basename])),
+          do: Path.join("releases", basename)
+
+    dirs =
+      ["bin", Path.join("releases", release.version), "erts-#{release.erts_version}"] ++
+        lib_dirs ++ release_files
+
+    files =
+      Enum.map(dirs, &{String.to_charlist(&1), String.to_charlist(Path.join(release.path, &1))})
+
+    File.rm(out_path)
+    :ok = :erl_tar.create(String.to_charlist(out_path), files, [:dereference, :compressed])
+    release
+  end
+
   # build_rel
 
   defp build_rel(release, config) do
diff --git a/lib/mix/test/mix/release_test.exs b/lib/mix/test/mix/release_test.exs
index d9dfd6087..59044219d 100644
--- a/lib/mix/test/mix/release_test.exs
+++ b/lib/mix/test/mix/release_test.exs
@@ -184,6 +184,14 @@ defmodule Mix.ReleaseTest do
                    fn -> release(steps: [:assemble, :assemble]) end
 
       assert_raise Mix.Error,
+                   ~r"The :tar step must come after :assemble",
+                   fn -> release(steps: [:tar, :assemble]) end
+
+      assert_raise Mix.Error,
+                   ~r"The :steps option can only contain the atom :tar once",
+                   fn -> release(steps: [:assemble, :tar, :tar]) end
+
+      assert_raise Mix.Error,
                    ~r"The :steps option must be",
                    fn -> release(steps: [:foo]) end
     end
diff --git a/lib/mix/test/mix/tasks/release_test.exs b/lib/mix/test/mix/tasks/release_test.exs
index 793347d73..dde079717 100644
--- a/lib/mix/test/mix/tasks/release_test.exs
+++ b/lib/mix/test/mix/tasks/release_test.exs
@@ -36,6 +36,49 @@ defmodule Mix.Tasks.ReleaseTest do
       end)
     end
 
+    test "tar" do
+      in_fixture("release_test", fn ->
+        config = [releases: [demo: [steps: [:assemble, :tar]]]]
+
+        Mix.Project.in_project(:release_test, ".", config, fn _ ->
+          root = Path.absname("_build/#{Mix.env()}/rel/demo")
+
+          ignored_app_path = Path.join([root, "lib", "ignored_app-0.1.0", "ebin"])
+          File.mkdir_p!(ignored_app_path)
+          File.touch(Path.join(ignored_app_path, "ignored_app.app"))
+
+          ignored_release_path = Path.join([root, "releases", "ignored_dir"])
+          File.mkdir_p!(ignored_release_path)
+          File.touch(Path.join(ignored_release_path, "ignored"))
+
+          Mix.Task.run("release")
+          tar_path = Path.expand(Path.join([root, "..", "..", "demo-0.1.0.tar.gz"]))
+          message = "* building #{tar_path}"
+          assert_received {:mix_shell, :info, [^message]}
+          assert File.exists?(tar_path)
+
+          {:ok, files} = String.to_charlist(tar_path) |> :erl_tar.table([:compressed])
+
+          files = Enum.map(files, &to_string/1)
+          files_with_versions = File.ls!(Path.join(root, "lib"))
+
+          assert "bin/demo" in files
+          assert "releases/0.1.0/sys.config" in files
+          assert "releases/0.1.0/vm.args" in files
+          assert "releases/COOKIE" in files
+          assert "releases/start_erl.data" in files
+
+          for dir <- files_with_versions -- ["ignored_app-0.1.0"] do
+            [name | _] = String.split(dir, "-")
+            assert "lib/#{dir}/ebin/#{name}.app" in files
+          end
+
+          refute "lib/ignored_app-0.1.0/ebin/ignored_app.app" in files
+          refute "releases/ignored_dir/ignored" in files
+        end)
+      end)
+    end
+
     test "steps" do
       in_fixture("release_test", fn ->
         last_step = fn release ->