Specs

decode_query(binary(), %{optional(binary()) => binary()}, :rfc3986 | :www_form) ::
  %{optional(binary()) => binary()}

Decodes query into a map.

Given a query string in the form of key1=value1&key2=value2..., this function inserts each key-value pair in the query string as one entry in the given map. Keys and values in the resulting map will be binaries. Keys and values will be percent-unescaped.

You can specify one of the following encoding options:

• :www_form - (default, since v1.12.0) keys and values are decoded as per decode_www_form/1. This is the format typically used by browsers on query strings and form data. It decodes "+" as " ".

• :rfc3986 - (since v1.12.0) keys and values are decoded as per decode/1. The result is the same as :www_form except for leaving "+" as is in line with RFC 3986.

Encoding defaults to :www_form for backward compatibility.

Use query_decoder/1 if you want to iterate over each value manually.

Examples

iex> URI.decode_query("foo=1&bar=2")
%{"bar" => "2", "foo" => "1"}

iex> URI.decode_query("percent=oh+yes%21", %{"starting" => "map"})
%{"percent" => "oh yes!", "starting" => "map"}

iex> URI.decode_query("percent=oh+yes%21", %{}, :rfc3986)
%{"percent" => "oh+yes!"}