View Source URI (Elixir v1.13.0-rc.0)
Utilities for working with URIs.
This module provides functions for working with URIs (for example, parsing URIs or encoding query strings). The functions in this module are implemented according to RFC 3986.
URIs are structs behind the scenes. You can access the URI fields directly
but you should not create a new URI
directly via the struct syntax. Instead
use the functions in this module.
Link to this section Summary
Functions
Checks if character
is a reserved one in a URI.
Checks if character
is allowed unescaped in a URI.
Checks if character
is an unreserved one in a URI.
Percent-unescapes a URI.
Decodes query
into a map.
Decodes string
as "x-www-form-urlencoded".
Returns the default port for a given scheme
.
Registers the default port
for the given scheme
.
Percent-escapes all characters that require escaping in string
.
Encodes enumerable
into a query string using encoding
.
Encodes string
as "x-www-form-urlencoded".
Merges two URIs.
Creates a new URI struct from a URI or a string.
Parses a well-formed URI into its components.
Returns a stream of two-element tuples representing key-value pairs in the
given query
.
Returns the string representation of the given URI struct.
Link to this section Types
@opaque authority()
Link to this section Functions
Checks if character
is a reserved one in a URI.
As specified in RFC 3986, section 2.2,
the following characters are reserved: :
, /
, ?
, #
, [
, ]
, @
, !
, $
, &
, '
, (
, )
, *
, +
, ,
, ;
, =
Examples
iex> URI.char_reserved?(?+)
true
Checks if character
is allowed unescaped in a URI.
This is the default used by URI.encode/2
where both
reserved and unreserved characters
are kept unescaped.
Examples
iex> URI.char_unescaped?(?{)
false
Checks if character
is an unreserved one in a URI.
As specified in RFC 3986, section 2.3, the following characters are unreserved:
- Alphanumeric characters:
A-Z
,a-z
,0-9
~
,_
,-
,.
Examples
iex> URI.char_unreserved?(?_)
true
Percent-unescapes a URI.
Examples
iex> URI.decode("https%3A%2F%2Felixir-lang.org")
"https://elixir-lang.org"
@spec 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 perdecode_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 perdecode/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!"}
Decodes string
as "x-www-form-urlencoded".
Note "x-www-form-urlencoded" is not specified as part of RFC 3986. However, it is a commonly used format to encode query strings and form data by browsers.
Examples
iex> URI.decode_www_form("%3Call+in%2F")
"<all in/"
@spec default_port(binary()) :: nil | non_neg_integer()
Returns the default port for a given scheme
.
If the scheme is unknown to the URI
module, this function returns
nil
. The default port for any scheme can be configured globally
via default_port/2
.
Examples
iex> URI.default_port("ftp")
21
iex> URI.default_port("ponzi")
nil
@spec default_port(binary(), non_neg_integer()) :: :ok
Registers the default port
for the given scheme
.
After this function is called, port
will be returned by
default_port/1
for the given scheme scheme
. Note that this function
changes the default port for the given scheme
globally, meaning for
every application.
It is recommended for this function to be invoked in your application's start callback in case you want to register new URIs.
@spec encode(binary(), (byte() -> as_boolean(term()))) :: binary()
Percent-escapes all characters that require escaping in string
.
This means reserved characters, such as :
and /
, and the
so-called unreserved characters, which have the same meaning both
escaped and unescaped, won't be escaped by default.
See encode_www_form/1
if you are interested in escaping reserved
characters too.
This function also accepts a predicate
function as an optional
argument. If passed, this function will be called with each byte
in string
as its argument and should return a truthy value (anything other
than false
or nil
) if the given byte should be left as is, or return a
falsy value (false
or nil
) if the character should be escaped. Defaults
to URI.char_unescaped?/1
.
Examples
iex> URI.encode("ftp://s-ite.tld/?value=put it+й")
"ftp://s-ite.tld/?value=put%20it+%D0%B9"
iex> URI.encode("a string", &(&1 != ?i))
"a str%69ng"
Encodes enumerable
into a query string using encoding
.
Takes an enumerable that enumerates as a list of two-element
tuples (for instance, a map or a keyword list) and returns a string
in the form of key1=value1&key2=value2...
.
Keys and values can be any term that implements the String.Chars
protocol with the exception of lists, which are explicitly forbidden.
You can specify one of the following encoding
strategies:
:www_form
- (default, since v1.12.0) keys and values are URL encoded as perencode_www_form/1
. This is the format typically used by browsers on query strings and form data. It encodes " " as "+".:rfc3986
- (since v1.12.0) the same as:www_form
except it encodes " " as "%20" according RFC 3986. This is the best option if you are encoding in a non-browser situation, since encoding spaces as "+" can be ambiguous to URI parsers. This can inadvertently lead to spaces being interpreted as literal plus signs.
Encoding defaults to :www_form
for backward compatibility.
Examples
iex> query = %{"foo" => 1, "bar" => 2}
iex> URI.encode_query(query)
"bar=2&foo=1"
iex> query = %{"key" => "value with spaces"}
iex> URI.encode_query(query)
"key=value+with+spaces"
iex> query = %{"key" => "value with spaces"}
iex> URI.encode_query(query, :rfc3986)
"key=value%20with%20spaces"
iex> URI.encode_query(%{key: [:a, :list]})
** (ArgumentError) encode_query/2 values cannot be lists, got: [:a, :list]
Encodes string
as "x-www-form-urlencoded".
Note "x-www-form-urlencoded" is not specified as part of RFC 3986. However, it is a commonly used format to encode query strings and form data by browsers.
Example
iex> URI.encode_www_form("put: it+й")
"put%3A+it%2B%D0%B9"
Merges two URIs.
This function merges two URIs as per RFC 3986, section 5.2.
Examples
iex> URI.merge(URI.parse("http://google.com"), "/query") |> to_string()
"http://google.com/query"
iex> URI.merge("http://example.com", "http://google.com") |> to_string()
"http://google.com"
Creates a new URI struct from a URI or a string.
If a %URI{}
struct is given, it returns {:ok, uri}
. If a string is
given, it will parse it and returns {:ok, uri}
. If the string is
invalid, it returns {:error, part}
instead, with the invalid part of the URI.
This function can parse both absolute and relative URLs. You can check
if a URI is absolute or relative by checking if the scheme
field is
nil
or not. All fields may be nil
, except for the path
.
When a URI is given without a port, the value returned by URI.default_port/1
for the URI's scheme is used for the :port
field. The scheme is also
normalized to lowercase.
Examples
iex> URI.new("https://elixir-lang.org/")
{:ok, %URI{
fragment: nil,
host: "elixir-lang.org",
path: "/",
port: 443,
query: nil,
scheme: "https",
userinfo: nil
}}
iex> URI.new("//elixir-lang.org/")
{:ok, %URI{
fragment: nil,
host: "elixir-lang.org",
path: "/",
port: nil,
query: nil,
scheme: nil,
userinfo: nil
}}
iex> URI.new("/foo/bar")
{:ok, %URI{
fragment: nil,
host: nil,
path: "/foo/bar",
port: nil,
query: nil,
scheme: nil,
userinfo: nil
}}
iex> URI.new("foo/bar")
{:ok, %URI{
fragment: nil,
host: nil,
path: "foo/bar",
port: nil,
query: nil,
scheme: nil,
userinfo: nil
}}
iex> URI.new("//[fe80::]/")
{:ok, %URI{
fragment: nil,
host: "fe80::",
path: "/",
port: nil,
query: nil,
scheme: nil,
userinfo: nil
}}
iex> URI.new("https:?query")
{:ok, %URI{
fragment: nil,
host: nil,
path: "",
port: 443,
query: "query",
scheme: "https",
userinfo: nil
}}
iex> URI.new("/invalid_greater_than_in_path/>")
{:error, ">"}
Giving an existing URI simply returns it wrapped in a tuple:
iex> {:ok, uri} = URI.new("https://elixir-lang.org/")
iex> URI.new(uri)
{:ok, %URI{
fragment: nil,
host: "elixir-lang.org",
path: "/",
port: 443,
query: nil,
scheme: "https",
userinfo: nil
}}
Similar to new/0
but raises URI.Error
if an invalid string is given.
Examples
iex> URI.new!("https://elixir-lang.org/")
%URI{
fragment: nil,
host: "elixir-lang.org",
path: "/",
port: 443,
query: nil,
scheme: "https",
userinfo: nil
}
iex> URI.new!("/invalid_greater_than_in_path/>")
** (URI.Error) cannot parse due to reason invalid_uri: ">"
Giving an existing URI simply returns it:
iex> uri = URI.new!("https://elixir-lang.org/")
iex> URI.new!(uri)
%URI{
fragment: nil,
host: "elixir-lang.org",
path: "/",
port: 443,
query: nil,
scheme: "https",
userinfo: nil
}
Parses a well-formed URI into its components.
This function is deprecated as it fails to raise in case of invalid URIs.
Use URI.new!/1
or URI.new/1
instead. In case you want to mimic the
behaviour of this function, you can do:
case URI.new(path) do
{:ok, uri} -> uri
{:error, _} -> %URI{path: path}
end
Also note this function sets the authority field, but the field has been
deprecated and it is not set by URI.new!/1
and URI.new/1
.
@spec query_decoder(binary(), :rfc3986 | :www_form) :: Enumerable.t()
Returns a stream of two-element tuples representing key-value pairs in the
given query
.
Key and value in each tuple will be binaries and 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 perdecode_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 perdecode/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.
Examples
iex> URI.query_decoder("foo=1&bar=2") |> Enum.to_list()
[{"foo", "1"}, {"bar", "2"}]
iex> URI.query_decoder("food=bread%26butter&drinks=tap%20water+please") |> Enum.to_list()
[{"food", "bread&butter"}, {"drinks", "tap water please"}]
iex> URI.query_decoder("food=bread%26butter&drinks=tap%20water+please", :rfc3986) |> Enum.to_list()
[{"food", "bread&butter"}, {"drinks", "tap water+please"}]
Returns the string representation of the given URI struct.
Examples
iex> uri = URI.parse("http://google.com")
iex> URI.to_string(uri)
"http://google.com"
iex> uri = URI.parse("foo://bar.baz")
iex> URI.to_string(uri)
"foo://bar.baz"