Phase 1 first chunk: inventory schema + DO droplet sync

Models:
- cloud_projects: arcadia-cloud's mirror of DO Projects, indexed by
  (provider, provider_id); tenant_id + purpose classify each project.
- cloud_resources: single unified resource table; kind-specific bits in
  attrs JSONB; first_seen_at / last_seen_at / stale_strike_count drive
  three-strike deletion.
- cloud_resource_events: append-only audit (discovered, updated, deleted,
  drift_detected, tagged, restored).

ArcadiaCloud.Cloud context owns the single upsert chokepoint that:
- inserts new with `discovered` event
- updates existing only when meaningful fields change
- restores tombstoned rows seen again
- bumps last_seen_at and resets strike count
mark_stale/3 implements the three-strike rule.

ArcadiaCloud.DigitalOcean.Client is a Req wrapper with auto-pagination.
Per-purpose token resolution via .Tokens (phase 1: env DO_API_TOKEN;
phase 2: vault). Per project_arcadia_cloud memory the long-term shape
is one PAT per queue purpose for rate-limit isolation.

ArcadiaCloud.Sync.Bootstrap ensures the skyai-internal DO Project exists
on first sync, idempotent thereafter. ArcadiaCloud.Sync.DropletsWorker
runs full droplet sync on the cloud_sync_full Oban queue.

InventoryController wired to real data: platform_admin sees all,
tenants see only their scope.

Live smoke test against real DO: 5 droplets synced; skyai-internal
project auto-created; events written; endpoint returns scoped results.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

lib/arcadia_cloud/cloud.ex

@@ -0,0 +1,184 @@
+defmodule ArcadiaCloud.Cloud do
+  @moduledoc """
+  Context for cloud resource inventory.
+
+  Single upsert chokepoint (`upsert_resource/2`) handles:
+    - insert new (emit `discovered` event)
+    - update existing (diff meaningful fields, emit `updated` event only when changed)
+    - bump last_seen_at + reset stale_strike_count
+    - restore previously-deleted resources
+
+  Stale handling is in `mark_stale/3` — three-strike deletion across syncs.
+  """
+
+  import Ecto.Query, warn: false
+
+  alias ArcadiaCloud.Repo
+  alias ArcadiaCloud.Cloud.{CloudProject, CloudResource, CloudResourceEvent}
+
+  @meaningful_fields ~w(status name region size_slug tags attrs cloud_project_id
+                        tenant_id deployment_id)a
+
+  # ---- projects -------------------------------------------------------------
+
+  def get_project_by_provider(provider, provider_id) do
+    Repo.get_by(CloudProject, provider: provider, provider_id: provider_id)
+  end
+
+  def ensure_project(attrs) when is_map(attrs) do
+    provider = attrs[:provider] || attrs["provider"]
+    provider_id = attrs[:provider_id] || attrs["provider_id"]
+
+    case get_project_by_provider(provider, provider_id) do
+      nil ->
+        %CloudProject{}
+        |> CloudProject.changeset(attrs)
+        |> Repo.insert()
+
+      project ->
+        project
+        |> CloudProject.changeset(attrs)
+        |> Repo.update()
+    end
+  end
+
+  def list_projects, do: Repo.all(CloudProject)
+
+  def skyai_internal_project do
+    Repo.get_by(CloudProject, purpose: "skyai-infra", name: "skyai-internal")
+  end
+
+  # ---- resources ------------------------------------------------------------
+
+  def upsert_resource(attrs, opts \\ []) when is_map(attrs) do
+    source = Keyword.get(opts, :source, "sync")
+    provider = attrs[:provider] || attrs["provider"]
+    provider_id = attrs[:provider_id] || attrs["provider_id"]
+    now = DateTime.utc_now() |> DateTime.truncate(:second)
+
+    attrs =
+      attrs
+      |> Map.put_new(:first_seen_at, now)
+      |> Map.put(:last_seen_at, now)
+      |> Map.put(:stale_strike_count, 0)
+
+    Repo.transaction(fn ->
+      case Repo.get_by(CloudResource, provider: provider, provider_id: provider_id) do
+        nil ->
+          {:ok, resource} =
+            %CloudResource{}
+            |> CloudResource.changeset(attrs)
+            |> Repo.insert()
+
+          write_event(resource, "discovered", nil, snapshot(resource), source)
+          resource
+
+        existing ->
+          before_snap = snapshot(existing)
+
+          {:ok, updated} =
+            existing
+            |> CloudResource.changeset(Map.delete(attrs, :first_seen_at))
+            |> Repo.update()
+
+          cond do
+            existing.deleted_at != nil ->
+              # Was tombstoned; now seen again. Clear deleted_at and emit restore.
+              {:ok, restored} =
+                updated
+                |> Ecto.Changeset.change(deleted_at: nil)
+                |> Repo.update()
+
+              write_event(restored, "restored", before_snap, snapshot(restored), source)
+              restored
+
+            meaningful_change?(before_snap, snapshot(updated)) ->
+              write_event(updated, "updated", before_snap, snapshot(updated), source)
+              updated
+
+            true ->
+              updated
+          end
+      end
+    end)
+  end
+
+  @doc """
+  Three-strike deletion: any resource of `kind` whose `last_seen_at` is older
+  than `sync_started_at` gets its strike count bumped. At 3 strikes, mark
+  deleted. Returns count of strikes + deletions.
+  """
+  def mark_stale(kind, sync_started_at, opts \\ []) do
+    threshold = Keyword.get(opts, :threshold, 3)
+
+    stale_query =
+      from r in CloudResource,
+        where: r.kind == ^kind,
+        where: r.last_seen_at < ^sync_started_at,
+        where: is_nil(r.deleted_at)
+
+    # bump strikes
+    {struck, _} =
+      Repo.update_all(stale_query, inc: [stale_strike_count: 1])
+
+    # mark deleted those at/past threshold
+    now = DateTime.utc_now() |> DateTime.truncate(:second)
+
+    delete_query =
+      from r in CloudResource,
+        where: r.kind == ^kind,
+        where: r.stale_strike_count >= ^threshold,
+        where: is_nil(r.deleted_at)
+
+    deleted = Repo.all(delete_query)
+
+    Enum.each(deleted, fn r ->
+      r
+      |> Ecto.Changeset.change(deleted_at: now)
+      |> Repo.update!()
+
+      write_event(r, "deleted", snapshot(r), nil, "sync_stale")
+    end)
+
+    %{struck: struck, deleted: length(deleted)}
+  end
+
+  def list_resources(opts \\ []) do
+    base = from r in CloudResource, where: is_nil(r.deleted_at), order_by: [desc: r.updated_at]
+
+    base
+    |> filter_by(:kind, opts[:kind])
+    |> filter_by(:tenant_id, opts[:tenant_id])
+    |> filter_by(:deployment_id, opts[:deployment_id])
+    |> Repo.all()
+  end
+
+  defp filter_by(query, _field, nil), do: query
+
+  defp filter_by(query, field, value) do
+    from(r in query, where: field(r, ^field) == ^value)
+  end
+
+  # ---- internals ------------------------------------------------------------
+
+  defp snapshot(%CloudResource{} = r) do
+    Map.take(r, @meaningful_fields ++ [:provider_id, :name, :id])
+  end
+
+  defp meaningful_change?(a, b) do
+    Map.take(a, @meaningful_fields) != Map.take(b, @meaningful_fields)
+  end
+
+  defp write_event(%CloudResource{id: id}, event, before, after_, source) do
+    %CloudResourceEvent{}
+    |> CloudResourceEvent.changeset(%{
+      resource_id: id,
+      event: event,
+      before: before,
+      after: after_,
+      source: source,
+      occurred_at: DateTime.utc_now() |> DateTime.truncate(:second)
+    })
+    |> Repo.insert!()
+  end
+end

lib/arcadia_cloud/cloud/cloud_project.ex

@@ -0,0 +1,29 @@
+defmodule ArcadiaCloud.Cloud.CloudProject do
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  @primary_key {:id, :binary_id, autogenerate: true}
+  @foreign_key_type :binary_id
+
+  schema "cloud_projects" do
+    field :provider, :string
+    field :provider_id, :string
+    field :name, :string
+    field :tenant_id, :binary_id
+    field :purpose, :string
+    field :metadata, :map, default: %{}
+
+    timestamps(type: :utc_datetime)
+  end
+
+  @required ~w(provider provider_id name purpose)a
+  @optional ~w(tenant_id metadata)a
+
+  def changeset(project, attrs) do
+    project
+    |> cast(attrs, @required ++ @optional)
+    |> validate_required(@required)
+    |> validate_inclusion(:purpose, ~w(tenant-workload skyai-infra shared-services))
+    |> unique_constraint([:provider, :provider_id])
+  end
+end

lib/arcadia_cloud/cloud/cloud_resource.ex

@@ -0,0 +1,40 @@
+defmodule ArcadiaCloud.Cloud.CloudResource do
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  @primary_key {:id, :binary_id, autogenerate: true}
+  @foreign_key_type :binary_id
+
+  schema "cloud_resources" do
+    field :provider, :string
+    field :provider_id, :string
+    field :kind, :string
+    field :name, :string
+    field :region, :string
+    field :status, :string
+    field :size_slug, :string
+    field :tenant_id, :binary_id
+    field :deployment_id, :binary_id
+    field :tags, {:array, :string}, default: []
+    field :attrs, :map, default: %{}
+    field :first_seen_at, :utc_datetime
+    field :last_seen_at, :utc_datetime
+    field :stale_strike_count, :integer, default: 0
+    field :deleted_at, :utc_datetime
+
+    belongs_to :cloud_project, ArcadiaCloud.Cloud.CloudProject
+
+    timestamps(type: :utc_datetime)
+  end
+
+  @required ~w(provider provider_id kind name status first_seen_at last_seen_at)a
+  @optional ~w(region size_slug cloud_project_id tenant_id deployment_id tags attrs
+               stale_strike_count deleted_at)a
+
+  def changeset(resource, attrs) do
+    resource
+    |> cast(attrs, @required ++ @optional)
+    |> validate_required(@required)
+    |> unique_constraint([:provider, :provider_id])
+  end
+end

lib/arcadia_cloud/cloud/cloud_resource_event.ex

@@ -0,0 +1,27 @@
+defmodule ArcadiaCloud.Cloud.CloudResourceEvent do
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  @primary_key {:id, :binary_id, autogenerate: true}
+  @foreign_key_type :binary_id
+
+  schema "cloud_resource_events" do
+    field :event, :string
+    field :before, :map
+    field :after, :map
+    field :source, :string
+    field :occurred_at, :utc_datetime
+
+    belongs_to :resource, ArcadiaCloud.Cloud.CloudResource
+  end
+
+  @required ~w(resource_id event source occurred_at)a
+  @optional ~w(before after)a
+
+  def changeset(event, attrs) do
+    event
+    |> cast(attrs, @required ++ @optional)
+    |> validate_required(@required)
+    |> validate_inclusion(:event, ~w(discovered updated deleted drift_detected tagged restored))
+  end
+end

lib/arcadia_cloud/digital_ocean/client.ex

@@ -0,0 +1,106 @@
+defmodule ArcadiaCloud.DigitalOcean.Client do
+  @moduledoc """
+  Thin Req wrapper over the DigitalOcean v2 API.
+
+  Token resolution: per-purpose, looked up via `ArcadiaCloud.DigitalOcean.Tokens`.
+  Phase 0/1: env var `DO_API_TOKEN`. Phase 2: from the secrets vault.
+
+  Paginated list endpoints stream all pages by default.
+  """
+
+  alias ArcadiaCloud.DigitalOcean.Tokens
+
+  @base "https://api.digitalocean.com/v2"
+  @page_size 100
+
+  # ---- public ---------------------------------------------------------------
+
+  def list_droplets(opts \\ []), do: list_paginated("/droplets", "droplets", opts)
+  def list_projects(opts \\ []), do: list_paginated("/projects", "projects", opts)
+
+  def create_project(name, purpose, description \\ "", opts \\ []) do
+    body = %{
+      name: name,
+      purpose: purpose,
+      description: description,
+      environment: "Development"
+    }
+
+    request(:post, "/projects", body: body, purpose: opts[:purpose] || "provisioning")
+    |> case do
+      {:ok, %{"project" => project}} -> {:ok, project}
+      other -> other
+    end
+  end
+
+  def list_project_resources(project_id, opts \\ []) do
+    list_paginated("/projects/#{project_id}/resources", "resources", opts)
+  end
+
+  def assign_to_project(project_id, urns, opts \\ []) when is_list(urns) do
+    request(:post, "/projects/#{project_id}/resources",
+      body: %{resources: urns},
+      purpose: opts[:purpose] || "provisioning"
+    )
+  end
+
+  # ---- core -----------------------------------------------------------------
+
+  defp list_paginated(path, root_key, opts) do
+    purpose = opts[:purpose] || "sync_full"
+    do_paginate(path, root_key, purpose, [], 1)
+  end
+
+  defp do_paginate(path, root_key, purpose, acc, page) do
+    params = [page: page, per_page: @page_size]
+
+    case request(:get, path, params: params, purpose: purpose) do
+      {:ok, %{} = body} ->
+        items = Map.get(body, root_key, [])
+        new_acc = acc ++ items
+
+        if has_next?(body) do
+          do_paginate(path, root_key, purpose, new_acc, page + 1)
+        else
+          {:ok, new_acc}
+        end
+
+      err ->
+        err
+    end
+  end
+
+  defp has_next?(%{"links" => %{"pages" => %{"next" => _}}}), do: true
+  defp has_next?(_), do: false
+
+  defp request(method, path, opts) do
+    purpose = Keyword.fetch!(opts, :purpose)
+
+    with {:ok, token} <- Tokens.fetch(purpose) do
+      req_opts =
+        [
+          method: method,
+          url: @base <> path,
+          headers: [{"authorization", "Bearer " <> token}],
+          retry: :transient,
+          max_retries: 3
+        ]
+        |> maybe_put(:params, opts[:params])
+        |> maybe_put(:json, opts[:body])
+
+      case Req.request(req_opts) do
+        {:ok, %Req.Response{status: status, body: body}} when status in 200..299 ->
+          {:ok, body}
+
+        {:ok, %Req.Response{status: status, body: body}} ->
+          {:error, {:http, status, body}}
+
+        {:error, exception} ->
+          {:error, {:transport, exception}}
+      end
+    end
+  end
+
+  defp maybe_put(opts, _key, nil), do: opts
+  defp maybe_put(opts, key, value), do: Keyword.put(opts, key, value)
+end

lib/arcadia_cloud/digital_ocean/tokens.ex

@@ -0,0 +1,24 @@
+defmodule ArcadiaCloud.DigitalOcean.Tokens do
+  @moduledoc """
+  DO API token resolver. Per-purpose so worker queues use separate tokens
+  (rate limit isolation + blast radius — see project_arcadia_cloud memory).
+
+  Phase 0/1 implementation: all purposes fall back to the single
+  `DO_API_TOKEN` env var (or `:default_token` app env).
+  Phase 2: read per-purpose bundles from the secrets vault.
+  """
+
+  @env_var "DO_API_TOKEN"
+
+  def fetch(purpose) when is_binary(purpose) do
+    case resolve(purpose) do
+      nil -> {:error, :no_token_configured}
+      token -> {:ok, token}
+    end
+  end
+
+  defp resolve(_purpose) do
+    Application.get_env(:arcadia_cloud, :do_api_token) ||
+      System.get_env(@env_var)
+  end
+end

lib/arcadia_cloud/sync/bootstrap.ex

@@ -0,0 +1,51 @@
+defmodule ArcadiaCloud.Sync.Bootstrap do
+  @moduledoc """
+  First-run bootstrap: ensure the `skyai-internal` DO Project exists and
+  is registered in our `cloud_projects` table. Resources discovered before
+  any tenant project exists land here by default.
+
+  Idempotent: safe to call on every sync.
+  """
+
+  alias ArcadiaCloud.Cloud
+  alias ArcadiaCloud.DigitalOcean.Client
+
+  @internal_name "skyai-internal"
+  @internal_purpose "skyai-infra"
+  @do_purpose "Service or API"
+
+  def ensure_skyai_internal do
+    case Cloud.skyai_internal_project() do
+      %{} = project ->
+        {:ok, project}
+
+      nil ->
+        with {:ok, do_project} <- find_or_create_do_project() do
+          {:ok, _local} =
+            Cloud.ensure_project(%{
+              provider: "digitalocean",
+              provider_id: do_project["id"],
+              name: @internal_name,
+              purpose: @internal_purpose,
+              metadata: %{
+                do_purpose: do_project["purpose"],
+                description: do_project["description"]
+              }
+            })
+        end
+    end
+  end
+
+  defp find_or_create_do_project do
+    with {:ok, projects} <- Client.list_projects() do
+      case Enum.find(projects, &(&1["name"] == @internal_name)) do
+        nil ->
+          Client.create_project(@internal_name, @do_purpose,
+            "Sky AI internal infrastructure (auto-created by arcadia-cloud)")
+
+        existing ->
+          {:ok, existing}
+      end
+    end
+  end
+end

lib/arcadia_cloud/sync/droplets_worker.ex

@@ -0,0 +1,78 @@
+defmodule ArcadiaCloud.Sync.DropletsWorker do
+  @moduledoc """
+  Full sync of DigitalOcean droplets.
+
+  Idempotent: re-runs are no-ops absent state changes. Three-strike deletion
+  for resources that vanish from N consecutive syncs.
+
+  Tenant attribution is derived in two passes — phase 1 (this worker) tags
+  all discovered resources to the `skyai-internal` project by default.
+  Phase 1+ will resolve actual tenant projects via DO Projects API.
+  """
+
+  use Oban.Worker, queue: :cloud_sync_full, max_attempts: 3
+
+  alias ArcadiaCloud.Cloud
+  alias ArcadiaCloud.DigitalOcean.Client
+  alias ArcadiaCloud.Sync.Bootstrap
+
+  @kind "droplet"
+  @provider "digitalocean"
+
+  @impl Oban.Worker
+  def perform(_job) do
+    sync_started_at = DateTime.utc_now() |> DateTime.truncate(:second)
+
+    with {:ok, _project} <- Bootstrap.ensure_skyai_internal(),
+         {:ok, droplets} <- Client.list_droplets() do
+      internal = Cloud.skyai_internal_project()
+
+      Enum.each(droplets, fn d ->
+        Cloud.upsert_resource(normalize(d, internal, sync_started_at))
+      end)
+
+      Cloud.mark_stale(@kind, sync_started_at)
+      :ok
+    end
+  end
+
+  # ---- normalization --------------------------------------------------------
+
+  defp normalize(d, project, now) do
+    %{
+      provider: @provider,
+      provider_id: to_string(d["id"]),
+      kind: @kind,
+      name: d["name"],
+      region: get_in(d, ["region", "slug"]),
+      status: normalize_status(d["status"]),
+      size_slug: d["size_slug"],
+      cloud_project_id: project && project.id,
+      tags: d["tags"] || [],
+      attrs: %{
+        memory_mb: d["memory"],
+        vcpus: d["vcpus"],
+        disk_gb: d["disk"],
+        image: take_image(d["image"]),
+        networks: d["networks"],
+        features: d["features"],
+        do_created_at: d["created_at"]
+      },
+      first_seen_at: now,
+      last_seen_at: now
+    }
+  end
+
+  defp normalize_status("active"), do: "active"
+  defp normalize_status("off"), do: "off"
+  defp normalize_status("new"), do: "provisioning"
+  defp normalize_status("archive"), do: "archived"
+  defp normalize_status(other) when is_binary(other), do: other
+  defp normalize_status(_), do: "unknown"
+
+  defp take_image(nil), do: nil
+
+  defp take_image(image) when is_map(image) do
+    Map.take(image, ["id", "name", "slug", "distribution"])
+  end
+end

lib/arcadia_cloud_web/controllers/inventory_controller.ex

@@ -1,12 +1,62 @@
 defmodule ArcadiaCloudWeb.InventoryController do
   @moduledoc """
-  Cloud resource inventory. Phase 0 stub — returns an empty list.
+  Cloud resource inventory.
-  Phase 1 wires this to `cloud_resources` filtered by tenant scope.
+
+  Scope rules (phase 1):
+    - platform_admin tenants see every non-deleted resource
+    - other tenants see only resources tagged to their tenant_id
+
+  Filters: `?kind=droplet`, `?deployment_id=...`
   """
 
   use ArcadiaCloudWeb, :controller
 
-  def index(conn, _params) do
+  alias ArcadiaCloud.Cloud
-    json(conn, %{resources: []})
+
+  def index(conn, params) do
+    identity = conn.assigns.current_identity
+
+    base_opts =
+      []
+      |> maybe_put(:kind, params["kind"])
+      |> maybe_put(:deployment_id, params["deployment_id"])
+
+    opts =
+      if platform_admin?(identity) do
+        base_opts
+      else
+        Keyword.put(base_opts, :tenant_id, identity.tenant_id)
+      end
+
+    resources =
+      Cloud.list_resources(opts)
+      |> Enum.map(&shape/1)
+
+    json(conn, %{resources: resources, count: length(resources)})
+  end
+
+  defp platform_admin?(%{roles: roles}) when is_list(roles), do: "platform_admin" in roles
+  defp platform_admin?(_), do: false
+
+  defp maybe_put(opts, _key, nil), do: opts
+  defp maybe_put(opts, _key, ""), do: opts
+  defp maybe_put(opts, key, value), do: Keyword.put(opts, key, value)
+
+  defp shape(r) do
+    %{
+      id: r.id,
+      provider: r.provider,
+      provider_id: r.provider_id,
+      kind: r.kind,
+      name: r.name,
+      region: r.region,
+      status: r.status,
+      size_slug: r.size_slug,
+      tenant_id: r.tenant_id,
+      deployment_id: r.deployment_id,
+      tags: r.tags,
+      first_seen_at: r.first_seen_at,
+      last_seen_at: r.last_seen_at
+    }
   end
 end

priv/repo/migrations/20260519120000_create_inventory.exs

@@ -0,0 +1,65 @@
+defmodule ArcadiaCloud.Repo.Migrations.CreateInventory do
+  use Ecto.Migration
+
+  def change do
+    create table(:cloud_projects, primary_key: false) do
+      add :id, :binary_id, primary_key: true
+      add :provider, :string, null: false
+      add :provider_id, :string, null: false
+      add :name, :string, null: false
+      add :tenant_id, :binary_id
+      add :purpose, :string, null: false
+      add :metadata, :map, default: %{}, null: false
+
+      timestamps(type: :utc_datetime)
+    end
+
+    create unique_index(:cloud_projects, [:provider, :provider_id])
+    create index(:cloud_projects, [:tenant_id])
+    create index(:cloud_projects, [:purpose])
+
+    create table(:cloud_resources, primary_key: false) do
+      add :id, :binary_id, primary_key: true
+      add :provider, :string, null: false
+      add :provider_id, :string, null: false
+      add :kind, :string, null: false
+      add :name, :string, null: false
+      add :region, :string
+      add :status, :string, null: false
+      add :size_slug, :string
+      add :cloud_project_id, references(:cloud_projects, type: :binary_id, on_delete: :nilify_all)
+      add :tenant_id, :binary_id
+      add :deployment_id, :binary_id
+      add :tags, {:array, :string}, default: [], null: false
+      add :attrs, :map, default: %{}, null: false
+      add :first_seen_at, :utc_datetime, null: false
+      add :last_seen_at, :utc_datetime, null: false
+      add :stale_strike_count, :integer, default: 0, null: false
+      add :deleted_at, :utc_datetime
+
+      timestamps(type: :utc_datetime)
+    end
+
+    create unique_index(:cloud_resources, [:provider, :provider_id])
+    create index(:cloud_resources, [:kind])
+    create index(:cloud_resources, [:tenant_id])
+    create index(:cloud_resources, [:deployment_id])
+    create index(:cloud_resources, [:cloud_project_id])
+    create index(:cloud_resources, [:last_seen_at])
+    create index(:cloud_resources, [:deleted_at])
+
+    create table(:cloud_resource_events, primary_key: false) do
+      add :id, :binary_id, primary_key: true
+      add :resource_id, references(:cloud_resources, type: :binary_id, on_delete: :delete_all),
+        null: false
+      add :event, :string, null: false
+      add :before, :map
+      add :after, :map
+      add :source, :string, null: false
+      add :occurred_at, :utc_datetime, null: false
+    end
+
+    create index(:cloud_resource_events, [:resource_id, :occurred_at])
+    create index(:cloud_resource_events, [:event])
+  end
+end