34 lines
		
	
	
	
		
			746 B
		
	
	
	
		
			Elixir
		
	
	
	
	
	
			
		
		
	
	
			34 lines
		
	
	
	
		
			746 B
		
	
	
	
		
			Elixir
		
	
	
	
	
	
# Pleroma: A lightweight social networking server
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# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
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# SPDX-License-Identifier: AGPL-3.0-only
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defmodule Pleroma.RepoStreamer do
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  alias Pleroma.Repo
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  import Ecto.Query
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  def chunk_stream(query, chunk_size) do
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    Stream.unfold(0, fn
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      :halt ->
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        {[], :halt}
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      last_id ->
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        query
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        |> order_by(asc: :id)
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        |> where([r], r.id > ^last_id)
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        |> limit(^chunk_size)
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        |> Repo.all()
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        |> case do
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          [] ->
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            {[], :halt}
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          records ->
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            last_id = List.last(records).id
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            {records, last_id}
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        end
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    end)
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    |> Stream.take_while(fn
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      [] -> false
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      _ -> true
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    end)
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  end
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end
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