what is this?

this is a minimal example showing how create nixos services which can be instantiated multiple times:

services.nixcloud.minimal.<name?>

benefits are:

• multiple instantiation

• each serivce has a unique ${storeDir}

• (in this example) service holds persistent state in a single directory

• as shown in minimal.nix with funkyExtra one can create options per webservice and they get appended into the nginx configuration from nixcloud-module-importer.nix

• minimal.nix is easy to implement, nginx.nix is rather complicated in comparison, for instance:

   config = config:
     let
       cfgCollection=config.services.nixcloud.${wsName};
     in {
  
     systemd.services = flip mapAttrs' cfgCollection (name: cfg:  #'
     let
       apacheConfigFile = pkgs.writeText "${cfg.uniqueName}.conf" ''
         ServerRoot ${httpd}
  

  on has to mapAttrs' the cfgCollection into individual cfg(s) which hold each individual configuration of a service.

problems are:

• nix-repl can only see the default value for ${stateDir} for each configured webservice

   nix-repl> config.services.nixcloud.minimal
   { music1 = { ... }; music2 = { ... }; }
  
   :p config.services.nixcloud.minimal.music1.stateDir
   ""
  

  this is caused by the fact that nixcloud-module-importer.nix changes the stateDir from the default to a 'different' value! however, since only the later configuration knows about music1 and music2 it can't be assigned in nginx.nix which is sad since it breaks the options system as we know it.

how to deploy

1. to see how this works, do this:

   in configuration.nix add this:

    imports =
      [ # Include the results of the hardware scan.
        ./hardware-configuration.nix
      ] ++ (import /tmp/minimal-example/all-nixcloud-services.nix { inherit config; inherit options; inherit lib; inherit pkgs;}).webservice-modules;
   
     services.nixcloud.minimal.music1 = {
       enable = true;
       funkyExtra = "''yay1''";
   
   
       proxyOptions = {
         port   = 40003;
         path   = "/example";
         domain = "example.com";
       };
     };
     services.nixcloud.minimal.music2 = {
       enable = true;
       funkyExtra = "''yay2''";
   
       proxyOptions = {
         port   = 40004;
         path   = "/example2";
         domain = "example.com";
       };
     };
   

2. then build the new system

   nixos-rebuild switch
   

3. finally open your browser

   chromium localhost:40003/example/
   

   or

   chromium localhost:40004/example/
   

   each page respectivly shows this:

    hello world: ''yay'' from minimal-music1 in subdirectory
   

4. visit the stateful directory

    cd /var/lib/minimal-music1
    ls -lathr