Invoke BSD rc scripts from compound process, document interactive multi-process containers, remove obsolete check for loading Docker images

README.md

@@ -847,6 +847,7 @@ createMultiProcessImage {
   tag = "test";
   exprFile = ../webapps-agnostic/processes.nix;
   processManager = "supervisord"; # sysvinit, disnix are also valid options
+  interactive = true; # the default option
   forceDisableUserChange = false; # the default option
 }
 ```
@@ -860,6 +861,11 @@ with the following parameters:
   process instances (as shown earlier)
 * The `processManager` parameter allows you to pick a process manager.
   Currently, all the options shown above are supported.
+* We can also specify whether we want to use the container interactively
+  with the `interactive` parameter (which defaults to: `true`). When
+  this setting has been enabled, a `.bashrc` will be configured to make
+  the bash shell usable, and a number of additional packages will be installed
+  for file and process management operations.
 * It is also possible to adjust the state settings in the processes model.
   With `forceDisableUserChange` we can disable user creation and user
   switching. It is also possible to control the other state variables, such
@@ -886,7 +892,16 @@ We can deploy a container instance from the image in interactive mode as
 follows:
 
 ```bash
-$ docker run --rm --network host -it multiprocess:test
+$ docker run --name mycontainer --rm --network host -it multiprocess:test
+```
+
+When interactive mode has been enabled, you should be able to "connect" to
+a container in which you can execute shell commands, for example to control
+the life-cycle of the sub processes:
+
+```
+$ docker exec -it mycontainer /bin/bash
+$ ps aux
 ```
 
 Examples

nixproc/create-compound-process/create-compound-process.nix

@@ -29,13 +29,15 @@ let
     else if processManager == "disnix" then import ./generate-disnix-args.nix {
       inherit pkgs system exprFile stateDir runtimeDir logDir cacheDir tmpDir forceDisableUserChange extraParams;
     }
-    # TODO: bsdrc -> similar to above
+    else if processManager == "bsdrc" then import ./generate-bsdrc-args.nix {
+      inherit pkgs system exprFile stateDir runtimeDir logDir cacheDir tmpDir forceDisableUserChange extraParams;
+    }
     else if processManager == "supervisord" then import ./generate-supervisord-args.nix {
       inherit pkgs system name compoundLogDir compoundRuntimeDir exprFile stateDir runtimeDir cacheDir logDir tmpDir forceDisableUserChange extraParams;
     }
 
-    # TODO: docker?
-    # We can't embed launchd, cygrunsrv, because these cannot be managed by anything else
+    # We can't embed launchd, cygrunsrv, because these supervisor processes cannot be managed by anything else
+    # Managing docker containers does not make sense
     # In theory, systemd could work in containers, but workarounds need to be applied, e.g. cgroup permissions
 
     else throw "Unsupported process manager: ${processManager}";

nixproc/create-compound-process/generate-bsdrc-args.nix

@@ -0,0 +1,29 @@
+{ pkgs, system
+, exprFile
+, stateDir
+, runtimeDir
+, logDir
+, cacheDir
+, tmpDir
+, forceDisableUserChange
+, extraParams
+}:
+
+let
+  generateCompoundProxyScript = import ./generate-compound-proxy.nix {
+    inherit (pkgs) stdenv writeTextFile;
+  };
+
+  profile = import ../create-managed-process/bsdrc/build-bsdrc-env.nix {
+    inherit pkgs system exprFile stateDir runtimeDir cacheDir logDir tmpDir forceDisableUserChange extraParams;
+  };
+
+  tools = (import ../../tools { inherit pkgs system; }).bsdrc;
+
+  proxyScript = generateCompoundProxyScript {
+    startCommand = "${tools}/bin/nixproc-bsdrc-runactivity start ${profile}";
+    stopCommand = "${tools}/bin/nixproc-bsdrc-runactivity -r stop ${profile}";
+  };
+in
+{ foregroundProcess = proxyScript;
+}

tools/docker/nixproc-docker-deploy.in

@@ -77,11 +77,8 @@ deployContainer()
         source $configDir/$containerName-docker-settings
         dockerContainerName="nixproc-$containerName"
 
-        # Load the Docker image if it does not exists
-        if [ "$(docker images -f "reference=$dockerImageTag" | wc -l)" = "1" ]
-        then
-            docker load -i $dockerImage
-        fi
+        # Load the Docker image (this operation is already idempotent)
+        docker load -i $dockerImage
 
         # Create the container if it does not exists yet
         if [ "$(docker ps -a -f "name=$dockerContainerName\$" | wc -l)" = "1" ]