Add Deletion APIs (#13)

lib/senzing/g2/engine.ex

@@ -422,6 +422,31 @@ defmodule Senzing.G2.Engine do
     end
   end
 
+  @doc """
+  This method is used to delete observation data from the system.
+
+  This removes a single entity observation record, by removing all of its
+  feature data and the observation itself.
+
+  See https://docs.senzing.com/python/3/g2engine/deleting/index.html#deleterecord
+
+  ## Examples
+
+      iex> :ok = Senzing.G2.Engine.add_record(%{"RECORD_ID" => "test id"}, "TEST")
+      iex> :ok = Senzing.G2.Engine.delete_record("test id", "TEST")
+
+  """
+  @doc type: :deleting_records
+  @spec delete_record(
+          record_id :: record_id(),
+          data_source :: data_source(),
+          opts :: [with_info: boolean(), load_id: String.t()]
+        ) :: G2.result() | G2.result(map())
+  def delete_record(record_id, data_source, opts \\ []) do
+    with {:ok, response} <- Nif.delete_record(data_source, record_id, opts[:load_id], opts[:with_info] || false),
+         do: {:ok, :json.decode(response)}
+  end
+
   # This method will destroy and perform cleanup for the G2 processing object.
   #
   # It should be called after all other calls are complete.

lib/senzing/g2/engine/nif.ex

@@ -343,6 +343,36 @@ defmodule Senzing.G2.Engine.Nif do
     return beam.make(env, .{ .ok, responseBuf }, .{});
   }
 
+  pub fn delete_record(env: beam.env, dataSource: []u8, recordId: []u8, loadId: ?[]u8, withInfo: bool) !beam.term {
+    var g2_dataSource = try beam.allocator.dupeZ(u8, dataSource);
+    var g2_recordId = try beam.allocator.dupeZ(u8, recordId);
+    var g2_loadId = if (loadId) |id| try beam.allocator.dupeZ(u8, id) else try beam.allocator.dupeZ(u8, "");
+
+    if (withInfo) {
+      var g2_flags: c_longlong = 0; // Reserved for future use, not currently used
+
+      var responseBuf: [*c]u8 = null;
+      var responseBufSize: usize = 1024;
+      var initialResponseBuf = try beam.allocator.alloc(u8, responseBufSize);
+      defer beam.allocator.free(initialResponseBuf);
+      responseBuf = initialResponseBuf.ptr;
+
+      if (G2.G2_deleteRecordWithInfo(g2_dataSource, g2_recordId, g2_loadId, g2_flags, &responseBuf, &responseBufSize, resize_pointer) != 0) {
+        var reason = try get_and_clear_last_exception(env);
+        return beam.make_error_pair(env, reason, .{});
+      }
+
+      return beam.make(env, .{ .ok, responseBuf }, .{});
+    }
+
+    if (G2.G2_deleteRecord(g2_dataSource, g2_recordId, g2_loadId) != 0) {
+      var reason = try get_and_clear_last_exception(env);
+      return beam.make_error_pair(env, reason, .{});
+    }
+
+    return beam.make(env, .ok, .{});
+  }
+
   // TODO: Complete
   pub fn get_entity_by_record_id(env: beam.env, dataSource: []u8, recordId: []u8) !beam.term {
     var g2_dataSource = try beam.allocator.dupeZ(u8, dataSource);

test/senzing/g2/engine_test.exs

@@ -202,4 +202,27 @@ defmodule Senzing.G2.EngineTest do
       assert {:ok, nil} = Engine.process_next_redo_record(return_info: true)
     end
   end
+
+  describe inspect(&Engine.delete_record/2) do
+    test "works", %{test: test} do
+      id = "#{inspect(__MODULE__)}.#{inspect(test)}"
+
+      assert :ok = Engine.add_record(%{"RECORD_ID" => id}, "TEST")
+
+      assert :ok = Engine.delete_record(id, "TEST")
+
+      assert :ok = Engine.add_record(%{"RECORD_ID" => id}, "TEST")
+
+      assert {:ok,
+              %{
+                "AFFECTED_ENTITIES" => _affected_entities,
+                "DATA_SOURCE" => "TEST",
+                "INTERESTING_ENTITIES" => %{"ENTITIES" => _entities},
+                "RECORD_ID" => ^id
+              }} = Engine.delete_record(id, "TEST", with_info: true)
+
+      # TODO: Use finished fn
+      assert {:error, {33, _message}} = Engine.Nif.get_entity_by_record_id("TEST", id)
+    end
+  end
 end