AJAX request abort on large query string Elixir Plug

问题

I am sending 2 large query string in AJAX requests, which are basically, a Base64 encoding of a jpeg(s). When the Camera is not a high-resolution one, AJAX request doesn't abort.

At first, I thought its a Nginx issue, Because I was getting an error as request entity too large I resolved it, Then I made changes to my Plug as

  plug Plug.Parsers,
    parsers: [
      :urlencoded,
      {:multipart, length: 20_000_000},
      :json
      ],
    pass: ["*/*"],
    query_string_length: 1_000_000,
    json_decoder: Poison

After defining query_string_length, Now I am not getting any errors like above but ajax request still abort.

Base64 encoding string size is 546,591 bytes or max.

I have tried to increase the AJAX request timeout to a very large timespan as well but it still fails. And I don't have any clue where the problem is right now.

How can we receive long strings in Plug?

Some of few answers on StackOverflow about this issue where people used AJAX and PHP, suggesting to change post_max_size, How can we do that in Elixir Plug?

回答1:

As you are sending AJAX request with JSON data, you should put the length config of json in the plug.

  plug Plug.Parsers,
    parsers: [
      :urlencoded,
      {:multipart, length: 20_000_000},
      {:json, length: 80_000_000},
      ],
    pass: ["*/*"],
    json_decoder: Poison

I suppose you will not put the data in the query string of the post, so the query_string_length - the maximum allowed size for query strings is not needed.

---Original answer---

For plug version around 1.4.3 and have no query_string_length option.

When you post the data as string, you are using Plug.Parsers.

If you are willing to process larger requests, please give a :length to Plug.Parsers.

You should change the code query_string_length: 1_000_000 to length: 20_000_000.

来源：https://stackoverflow.com/questions/49232227/ajax-request-abort-on-large-query-string-elixir-plug

标签

ajax

elixir