From d2fb84c6e09aa61f79714d7db1e0bb717da2c6d9 Mon Sep 17 00:00:00 2001
From: Matt Schreiber <schreibah@gmail.com>
Date: Mon, 27 Jan 2020 14:20:11 -0500
Subject: [PATCH] feat: add arbitrary Docker image tarball example

and associated subtest.

This tests the functionality of the newly-added
`services.<name>.image.tarball` parameter.
---
 examples/custom-image/arion-compose.nix | 48 +++++++++++++++++++++++++
 examples/custom-image/arion-pkgs.nix    |  6 ++++
 tests/arion-test/default.nix            | 13 +++++++
 3 files changed, 67 insertions(+)
 create mode 100644 examples/custom-image/arion-compose.nix
 create mode 100644 examples/custom-image/arion-pkgs.nix

diff --git a/examples/custom-image/arion-compose.nix b/examples/custom-image/arion-compose.nix
new file mode 100644
index 0000000..13b5d5b
--- /dev/null
+++ b/examples/custom-image/arion-compose.nix
@@ -0,0 +1,48 @@
+{ pkgs, ... }:
+
+let
+  webRoot = "/www";
+
+  webserverImage = pkgs.dockerTools.buildLayeredImage {
+    name = "a-webserver";
+
+    config = {
+      Entrypoint = [
+        "${pkgs.darkhttpd}/bin/darkhttpd"
+        webRoot
+      ];
+
+      Volumes = {
+        "${webRoot}" = { };
+      };
+    };
+  };
+in
+{
+  project.name = "custom-image";
+  services = {
+
+    webserver = {
+      image.tarball = webserverImage;
+
+      # The following is essentially equivalent to
+      #
+      #   { image.tarball = webserverImage; }
+      #
+      # It is included here as a demonstration of how to configure Arion to
+      # load a Docker image from *any* valid image tarball, not just one
+      # produced with a `pkgs.dockerTools` builder function.
+      #image.tarball = webserverImage.outPath;
+      #image.name = webserverImage.imageName;
+      #image.tag = webserverImage.imageTag;
+
+      service.command = [ "--port" "8000" ];
+      service.ports = [
+        "8000:8000" # host:container
+      ];
+      service.volumes = [
+        "${pkgs.nix.doc}/share/doc/nix/manual:${webRoot}"
+      ];
+    };
+  };
+}
diff --git a/examples/custom-image/arion-pkgs.nix b/examples/custom-image/arion-pkgs.nix
new file mode 100644
index 0000000..69aad13
--- /dev/null
+++ b/examples/custom-image/arion-pkgs.nix
@@ -0,0 +1,6 @@
+# Instead of pinning Nixpkgs, we can opt to use the one in NIX_PATH
+import <nixpkgs> {
+  # We specify the architecture explicitly. Use a Linux remote builder when
+  # calling arion from other platforms.
+  system = "x86_64-linux";
+}
diff --git a/tests/arion-test/default.nix b/tests/arion-test/default.nix
index a366309..961d9ce 100644
--- a/tests/arion-test/default.nix
+++ b/tests/arion-test/default.nix
@@ -39,6 +39,7 @@ in
       # Pre-build the image because we don't want to build the world
       # in the vm.
       (preEval [ ../../examples/minimal/arion-compose.nix ]).config.out.dockerComposeYaml
+      (preEval [ ../../examples/custom-image/arion-compose.nix ]).config.out.dockerComposeYaml
       (preEval [ ../../examples/full-nixos/arion-compose.nix ]).config.out.dockerComposeYaml
       (preEval [ ../../examples/nixos-unit/arion-compose.nix ]).config.out.dockerComposeYaml
       (preEval [ ../../examples/traefik/arion-compose.nix ]).config.out.dockerComposeYaml
@@ -66,6 +67,18 @@ in
         )
         machine.wait_until_fails("curl --fail localhost:8000")
 
+    # Tests
+    #  - examples/custom-image
+    with subtest("custom-image"):
+        machine.succeed(
+            "rm -rf work && cp -frT ${../../examples/custom-image} work && cd work && NIX_PATH=nixpkgs='${pkgs.path}' arion up -d"
+        )
+        machine.wait_until_succeeds("curl --fail localhost:8000")
+        machine.succeed(
+            "cd work && NIX_PATH=nixpkgs='${pkgs.path}' arion down"
+        )
+        machine.wait_until_fails("curl --fail localhost:8000")
+
     # Tests
     #  - running same image again doesn't require a `docker load`
     with subtest("docker load only once"):