Parses multipart request body.

Options

All options supported by Plug.Conn.read_body/2 are also supported here. They are repeated here for convenience:

• :length - sets the maximum number of bytes to read from the request, defaults to 8_000_000 bytes. Unlike Plug.Conn.read_body/2 supports passing an MFA ({module, function, args}) which will be evaluated on every request to determine the value.

• :read_length - sets the amount of bytes to read at one time from the underlying socket to fill the chunk, defaults to 1_000_000 bytes

• :read_timeout - sets the timeout for each socket read, defaults to 15_000ms

So by default, Plug.Parsers will read 1_000_000 bytes at a time from the socket with an overall limit of 8_000_000 bytes.

Besides the options supported by Plug.Conn.read_body/2, the multipart parser also checks for:

• :headers - containing the same :length, :read_length and :read_timeout options which are used explicitly for parsing multipart headers.
• :include_unnamed_parts_at - string specifying a body parameter that can hold a lists of body parts that didn't have a 'Content-Disposition' header. For instance, include_unnamed_parts_at: "_parts" would result in a body parameter "_parts", containing a list of parts, each with :body and :headers fields, like [%{body: "{}", headers: [{"content-type", "application/json"}]}].
• :validate_utf8 - specifies whether multipart body parts should be validated as utf8 binaries. Defaults to true.