Code polish, minor refactors, and type hints

lib/gc_index_relay/nostr.ex

@@ -5,7 +5,7 @@ defmodule GcIndexRelay.Nostr do
   ## Supported Operations
 
   The Nostr context module supports create, read, and delete operations on events, as well as a
-  number of query types to find collections of events. Update operations are not supported, sincafter
+  number of query types to find collections of events. Update operations are not supported, since a
   Nostr event, once signed, is immutable.
   """
 
@@ -20,7 +20,8 @@ defmodule GcIndexRelay.Nostr do
 
   Returns: `GcIndexRelay.Nostr.PubEvent`
   """
-  def get_event!(id) when is_binary(id) do
+  @spec get_event(binary()) :: {:ok, PubEvent.t()} | {:error, :not_found}
+  def get_event(id) when is_binary(id) do
     Event
     |> Repo.get(id)
     |> Repo.preload(:tags)
@@ -38,14 +39,13 @@ defmodule GcIndexRelay.Nostr do
       %Event{}
       |> Event.changeset(Map.from_struct(db_event))
       |> Repo.insert()
-    else
-      {:error, reason} -> {:error, reason}
     end
   end
 
   @doc """
   Deletes a `GcIndexRelay.Nostr.PubEvent` from the database.
   """
+  @spec delete_event(PubEvent.t()) :: {:ok, Ecto.Schema.t()} | {:error, Ecto.Changeset.t()}
   def delete_event(event) when is_struct(event, PubEvent) do
     db_event = PubEvent.to_db(event)
 

lib/gc_index_relay/nostr/event.ex

@@ -21,12 +21,10 @@ defmodule GcIndexRelay.Nostr.Event do
 
   @primary_key {:id, :binary_id, autogenerate: false}
   schema "events" do
-    # 32-bytes lowercase hex-encoded
     field :pubkey, :binary
     field :created_at, :utc_datetime
     field :kind, :integer
     field :content, :string
-    # 64 bytes lowercase hex-encoded
     field :sig, :binary
     has_many :tags, GcIndexRelay.Nostr.Tag
   end

lib/gc_index_relay/nostr/filter.ex

@@ -46,8 +46,6 @@ defmodule GcIndexRelay.Nostr.Filter do
          until: until,
          limit: limit
        }}
-    else
-      {:error, reason} -> {:error, reason}
     end
   end
 
@@ -139,8 +137,6 @@ defmodule GcIndexRelay.Nostr.Filter do
     with :ok <- validate_tag_keys(tags),
          :ok <- validate_tag_values(tags) do
       {:ok, tags}
-    else
-      {:error, reason} -> {:error, reason}
     end
   end
 
@@ -257,7 +253,7 @@ defmodule GcIndexRelay.Nostr.Filter do
   @spec apply_authors(Ecto.Query.t(), [String.t()] | nil) :: Ecto.Query.t()
   defp apply_authors(query, nil), do: query
   defp apply_authors(query, []), do: query
-  defp apply_authors(query, authors), do: where(query, [e], e.author in ^authors)
+  defp apply_authors(query, authors), do: where(query, [e], e.pubkey in ^authors)
 
   @spec apply_kinds(Ecto.Query.t(), [integer()] | nil) :: Ecto.Query.t()
   defp apply_kinds(query, nil), do: query

lib/gc_index_relay/nostr/pub_event.ex

@@ -12,42 +12,53 @@ defmodule GcIndexRelay.Nostr.PubEvent do
   @derive Jason.Encoder
   defstruct [:id, :pubkey, :created_at, :kind, :tags, :content, :sig]
 
+  @type t :: %__MODULE__{
+          id: binary(),
+          pubkey: binary(),
+          created_at: integer(),
+          kind: integer(),
+          tags: [[String.t()]],
+          content: String.t(),
+          sig: binary()
+        }
+
   @doc """
   Converts a `GcIndexRelay.Nostr.PubEvent` to its corresponding `GcIndexRelay.Nostr.Event` and
   `GcIndexRelay.Nostr.Tag` representations.
 
-  Returns an Ecto changeset for `GcIndexRelay.Nostr.Event`.
+  Returns an Ecto for `GcIndexRelay.Nostr.Event`.
   """
+  @spec to_db(t()) :: Ecto.Schema.t()
   def to_db(%__MODULE__{tags: tags} = pub_event) do
     %Event{to_event(pub_event) | tags: to_tags(tags)}
   end
 
-  defp to_event(%__MODULE__{
+  @spec to_event(t()) :: Ecto.Schema.t()
+  defp to_event(%__MODULE__{} = pub_event)
+       when is_binary(pub_event.id) and is_binary(pub_event.pubkey) and
+              is_integer(pub_event.created_at) and is_integer(pub_event.kind) and
+              is_binary(pub_event.sig) do
+    with {:ok, id} <- Base.decode16(pub_event.id, case: :lower),
+         {:ok, pubkey} <- Base.decode16(pub_event.pubkey, case: :lower),
+         {:ok, signature} <- Base.decode16(pub_event.sig, case: :lower) do
+      %Event{
         id: id,
         pubkey: pubkey,
-         created_at: epoch,
-         kind: kind,
-         content: content,
+        created_at: DateTime.from_unix!(pub_event.created_at),
+        kind: pub_event.kind,
+        content: pub_event.content,
         sig: signature
-       })
-       when is_binary(id) and is_binary(pubkey) and is_integer(epoch) and is_integer(kind) and
-              is_binary(signature) do
-    %Event{
-      id: Base.decode16(id, case: :lower),
-      pubkey: Base.decode16(pubkey, case: :lower),
-      created_at: DateTime.from_unix!(epoch),
-      kind: kind,
-      content: content,
-      sig: Base.decode16(signature, case: :lower)
       }
+    else
+      error -> {:error, error}
     end
-
-  defp to_tags(tags) when is_list(tags) do
-    for t <- tags, do: to_tag(t)
   end
 
-  defp to_tag(tag) when is_list(tag) do
-    [name | values] = tag
+  @spec to_tags([[String.t()]]) :: [Ecto.Schema.t()]
+  defp to_tags(tags) when is_list(tags) do
+    for t <- tags do
+      [name | values] = t
+      # Single-element tags will cause a crash
       [value | rest] = values
 
       %Tag{
@@ -56,13 +67,17 @@ defmodule GcIndexRelay.Nostr.PubEvent do
         additional_values: rest
       }
     end
+  end
 
   @doc """
   Converts the DB representations of `GcIndexRelay.Nostr.Event` and `GcIndexRelay.Nostr.Tag` to the
   domain representation `GcIndexRelay.Nostr.PubEvent`.
   """
+  @spec from_db(struct()) :: {:ok, t()} | {:error, :not_found}
+  def from_db(event) when is_nil(event), do: {:error, :not_found}
+
   def from_db(%Event{tags: tags} = event) when is_struct(event, Event) and is_list(tags) do
-    %{from_event(event) | tags: from_tags(tags)}
+    {:ok, %{from_event(event) | tags: from_tags(tags)}}
   end
 
   defp from_event(%Event{} = event) when is_struct(event, Event) do
@@ -77,11 +92,6 @@ defmodule GcIndexRelay.Nostr.PubEvent do
   end
 
   defp from_tags(tags) when is_list(tags) do
-    for t <- tags, do: from_tag(t)
-  end
-
-  defp from_tag(%Tag{name: name, value: value, additional_values: rest})
-       when is_binary(name) and is_binary(value) and is_list(rest) do
-    [name | [value | rest]]
+    for t <- tags, do: [t.name, t.value | t.additional_values]
   end
 end

lib/gc_index_relay_web/controllers/event_controller.ex

@@ -3,6 +3,7 @@ defmodule GcIndexRelayWeb.EventController do
 
   alias GcIndexRelay.Nostr
   alias GcIndexRelay.Nostr.Event
+  alias GcIndexRelay.Nostr.PubEvent
 
   action_fallback GcIndexRelayWeb.FallbackController
 
@@ -18,14 +19,13 @@ defmodule GcIndexRelayWeb.EventController do
 
   def show(conn, %{"id" => id}) do
     # TODO: Add 404 for event not found in FallbackController
-    event = Nostr.get_event!(id)
+    event = Nostr.get_event(id)
     render(conn, :show, event: event)
   end
 
   def delete(conn, %{"id" => id}) do
-    event = Nostr.get_event!(id)
-
-    with {:ok, %Event{}} <- Nostr.delete_event(event) do
+    with {:ok, %PubEvent{} = pub_event} <- Nostr.get_event(id),
+         {:ok, %Event{} = _} <- Nostr.delete_event(pub_event) do
       send_resp(conn, :no_content, "")
     end
   end