Phoenixで Repo.get!/2 で存在しないidを指定した場合など Ecto.NoResultsError がraiseされた場合に、Phoenixでは500ではなく404でレスポンスが返ってきます。 devtoolやPhoenixのログを見ても、404エラー(Not Found)としてレスポンスを返していることが分かります。 [info] GET /posts/1 [debug] Processing with SampleWeb.PostController.show/2 Parameters: %{"id" => "1"} Pipelines: [:browser] [debug] QUERY OK source="posts" db=0.3ms idle=1189.8ms SELECT p0."id", p0."body", p0."title", p0."inserte
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