feat: Added automatic script copying functionality

infra/modules/dev/main.tf

@@ -94,6 +94,14 @@ resource "hcloud_volume" "storage" {
   }
 }
 
+locals {
+  # Hetzner's automount convention (hc-utils' 99-hc-volume-automount.rules) is
+  # always /mnt/HC_Volume_<id> - deterministic once the volume exists, since the
+  # id is stable for the volume's lifetime regardless of which server it's
+  # attached to.
+  data_dir = "/mnt/HC_Volume_${hcloud_volume.storage.id}"
+}
+
 # Renders services/dev/Runners/docker-compose.yml directly into the repo, with
 # one runner service per var.runner_count. This only touches the local working
 # tree - deploying the change still goes through the normal scp + spinup.sh flow.
@@ -101,6 +109,74 @@ resource "local_file" "runners_compose" {
   filename = "${path.root}/../services/dev/Runners/docker-compose.yml"
   content = templatefile("${path.module}/templates/runners-docker-compose.yml.tftpl", {
     runner_count = var.runner_count
+    data_dir     = local.data_dir
   })
   file_permission = "0644"
 }
+
+# DATA_DIR is picked up automatically by `docker compose` (which auto-loads
+# .env from its working directory) for every dev/*-docker-compose.yml bind
+# mount - see services/dev/*.yml. Not committed (see .gitignore): it's tied to
+# the live volume's ID, so it's regenerated by tofu apply, not handed off via git.
+resource "local_file" "env" {
+  filename        = "${path.root}/../services/dev/.env"
+  content         = "DATA_DIR=${local.data_dir}\n"
+  file_permission = "0644"
+}
+
+locals {
+  # Everything under services/dev except the two files above: those are
+  # tracked via their own resource content (reading them back with fileset()/
+  # filesha1() before they exist would fail during `tofu plan`).
+  dev_static_files = sort([
+    for f in fileset("${path.root}/../services/dev", "**") :
+    f if f != ".env" && f != "Runners/docker-compose.yml"
+  ])
+
+  dev_static_files_hash = sha1(join("", [
+    for f in local.dev_static_files : filesha1("${path.root}/../services/dev/${f}")
+  ]))
+}
+
+# Copies services/dev to the server on every apply that changes it (a hand-edited
+# compose file, a new runner count, ...) or recreates the server - not just once
+# at first creation. Split from hcloud_server.this because it must run after the
+# generated files above, which in turn depend on the volume, which depends on
+# the server - so it can't be a provisioner on the server resource itself.
+resource "null_resource" "deploy_services" {
+  triggers = {
+    server_id    = hcloud_server.this.id
+    static_files = local.dev_static_files_hash
+    env          = local_file.env.content
+    runners      = local_file.runners_compose.content
+  }
+
+  connection {
+    type        = "ssh"
+    host        = hcloud_server.this.ipv4_address
+    user        = "root"
+    private_key = file(var.ssh_private_key_path)
+  }
+
+  provisioner "remote-exec" {
+    inline = ["mkdir -p /home/${var.deploy_user}/services"]
+  }
+
+  provisioner "file" {
+    source      = "${path.root}/../services/dev"
+    destination = "/home/${var.deploy_user}/services"
+  }
+
+  provisioner "remote-exec" {
+    inline = [
+      "chown -R ${var.deploy_user}:${var.deploy_user} /home/${var.deploy_user}/services",
+      "chmod +x /home/${var.deploy_user}/services/dev/*.sh",
+    ]
+  }
+
+  depends_on = [
+    hcloud_server.this,
+    local_file.env,
+    local_file.runners_compose,
+  ]
+}