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URI
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.
Types
- authority() deprecated
Functions
- %URI{}
-
The URI struct.
- append_path(uri, path)
-
Appends
path
to the givenuri
. - append_query(uri, query)
-
Appends
query
to the givenuri
. - char_reserved?(character)
-
Checks if
character
is a reserved one in a URI. - char_unescaped?(character)
-
Checks if
character
is allowed unescaped in a URI. - char_unreserved?(character)
-
Checks if
character
is an unreserved one in a URI. - decode(uri)
-
Percent-unescapes a URI.
- decode_query(query, map \\ %{}, encoding \\ :www_form)
-
Decodes
query
into a map. - decode_www_form(string)
-
Decodes
string
as "x-www-form-urlencoded". - default_port(scheme)
-
Returns the default port for a given
scheme
. - default_port(scheme, port)
-
Registers the default
port
for the givenscheme
. - encode(string, predicate \\ &char_unescaped?/1)
-
Percent-escapes all characters that require escaping in
string
. - encode_query(enumerable, encoding \\ :www_form)
-
Encodes
enumerable
into a query string usingencoding
. - encode_www_form(string)
-
Encodes
string
as "x-www-form-urlencoded". - merge(uri, rel)
-
Merges two URIs.
- new(uri)
-
Creates a new URI struct from a URI or a string.
- parse(uri)
-
Parses a URI into its components, without further validation.
- query_decoder(query, encoding \\ :www_form)
-
Returns a stream of two-element tuples representing key-value pairs in the given
query
. - to_string(uri)
-
Returns the string representation of the given URI struct.
authority()Source
@opaque authority()
t()Source
@type t() :: %URI{
authority: authority(),
fragment: nil | binary(),
host: nil | binary(),
path: nil | binary(),
port: nil | :inet.port_number(),
query: nil | binary(),
scheme: nil | binary(),
userinfo: nil | binary()
}
%URI{}Source
The URI struct.
The fields are defined to match the following URI representation (with field names between brackets):
[scheme]://[userinfo]@[host]:[port][path]?[query]#[fragment]
Note the authority
field is deprecated. parse/1
will still populate it for backwards compatibility but you should generally avoid setting or getting it.
append_path(uri, path)Source
@spec append_path(t(), String.t()) :: t()
Appends path
to the given uri
.
Path must start with /
and cannot contain additional URL components like fragments or query strings. This function further assumes the path is valid and it does not contain a query string or fragment parts.
Examples
iex> URI.append_path(URI.parse("http://example.com/foo/?x=1"), "/my-path") |> URI.to_string()
"http://example.com/foo/my-path?x=1"
iex> URI.append_path(URI.parse("http://example.com"), "my-path")
** (ArgumentError) path must start with "/", got: "my-path"
append_query(uri, query)Source
@spec append_query(t(), binary()) :: t()
Appends query
to the given uri
.
The given query
is not automatically encoded, use encode/2
or encode_www_form/1
.
Examples
iex> URI.append_query(URI.parse("http://example.com/"), "x=1") |> URI.to_string()
"http://example.com/?x=1"
iex> URI.append_query(URI.parse("http://example.com/?x=1"), "y=2") |> URI.to_string()
"http://example.com/?x=1&y=2"
iex> URI.append_query(URI.parse("http://example.com/?x=1"), "x=2") |> URI.to_string()
"http://example.com/?x=1&x=2"
char_reserved?(character)Source
@spec char_reserved?(byte()) :: boolean()
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
char_unescaped?(character)Source
@spec char_unescaped?(byte()) :: boolean()
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
char_unreserved?(character)Source
@spec char_unreserved?(byte()) :: boolean()
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
decode(uri)Source
@spec decode(binary()) :: binary()
Percent-unescapes a URI.
Examples
iex> URI.decode("https%3A%2F%2Felixir-lang.org")
"https://elixir-lang.org"
decode_query(query, map \\ %{}, encoding \\ :www_form)Source
@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!"}
decode_www_form(string)Source
@spec decode_www_form(binary()) :: binary()
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/"
default_port(scheme)Source
@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
default_port(scheme, port)Source
@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.
encode(string, predicate \\ &char_unescaped?/1)Source
@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"
encode_query(enumerable, encoding \\ :www_form)Source
@spec encode_query(Enumerable.t(), :rfc3986 | :www_form) :: binary()
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]
encode_www_form(string)Source
@spec encode_www_form(binary()) :: binary()
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"
merge(uri, rel)Source
@spec merge(t() | binary(), t() | binary()) :: t()
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"
new(uri)Source
@spec new(t() | String.t()) :: {:ok, t()} | {:error, String.t()}
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 and validate it. If the string is valid, it returns {:ok, uri}
, otherwise it returns {:error, part}
with the invalid part of the URI. For parsing URIs without further validation, see parse/1
.
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.
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: nil,
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
}}
new!(uri)Source
@spec new!(t() | String.t()) :: t()
Similar to new/1
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
}
parse(uri)Source
@spec parse(t() | binary()) :: t()
Parses a URI into its components, without further validation.
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. Furthermore, this function expects both absolute and relative URIs to be well-formed and does not perform any validation. See the "Examples" section below. Use new/1
if you want to validate the URI fields after parsing.
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.
If a %URI{}
struct is given to this function, this function returns it unmodified.
:authority
fieldThis function sets the field
:authority
for backwards-compatibility reasons but it is deprecated.
Examples
iex> URI.parse("https://elixir-lang.org/")
%URI{
authority: "elixir-lang.org",
fragment: nil,
host: "elixir-lang.org",
path: "/",
port: 443,
query: nil,
scheme: "https",
userinfo: nil
}
iex> URI.parse("//elixir-lang.org/")
%URI{
authority: "elixir-lang.org",
fragment: nil,
host: "elixir-lang.org",
path: "/",
port: nil,
query: nil,
scheme: nil,
userinfo: nil
}
iex> URI.parse("/foo/bar")
%URI{
fragment: nil,
host: nil,
path: "/foo/bar",
port: nil,
query: nil,
scheme: nil,
userinfo: nil
}
iex> URI.parse("foo/bar")
%URI{
fragment: nil,
host: nil,
path: "foo/bar",
port: nil,
query: nil,
scheme: nil,
userinfo: nil
}
In contrast to URI.new/1
, this function will parse poorly-formed URIs, for example:
iex> URI.parse("/invalid_greater_than_in_path/>")
%URI{
fragment: nil,
host: nil,
path: "/invalid_greater_than_in_path/>",
port: nil,
query: nil,
scheme: nil,
userinfo: nil
}
Another example is a URI with brackets in query strings. It is accepted by parse/1
, it is commonly accepted by browsers, but it will be refused by new/1
:
iex> URI.parse("/?foo[bar]=baz")
%URI{
fragment: nil,
host: nil,
path: "/",
port: nil,
query: "foo[bar]=baz",
scheme: nil,
userinfo: nil
}
query_decoder(query, encoding \\ :www_form)Source
@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"}]
to_string(uri)Source
@spec to_string(t()) :: binary()
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"
© 2012 Plataformatec
Licensed under the Apache License, Version 2.0.
https://hexdocs.pm/elixir/1.15.4/URI.html