Elixir v1.3.0-rc.0 URI View Source
Utilities for working with URIs.
This module provides functions for working with URIs (for example, parsing URIs or encoding query strings). For reference, most of the functions in this module refer to RFC 3986.
Link to this section Summary
Functions
Checks if the character is a “reserved” character in a URI
Checks if the character is allowed unescaped in a URI
Checks if the character is a “unreserved” character in a URI
Percent-unescapes a URI
Decodes a query string into a map
Decodes a string as “x-www-form-urlencoded”
Returns the default port for a given scheme
Registers the default port port
for the given scheme
Percent-escapes the given string
Encodes an enumerable into a query string
Encodes a string as “x-www-form-urlencoded”
Merges two URIs
Parses a well-formed URI reference 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
t() :: %URI{authority: nil | binary, fragment: nil | binary, host: nil | binary, path: nil | binary, port: nil | :inet.port_number, query: nil | binary, scheme: nil | binary, userinfo: nil | binary}
Link to this section Functions
Checks if the character is a “reserved” character in a URI.
Reserved characters are specified in RFC 3986, section 2.2.
Examples
iex> URI.char_reserved?(?+)
true
Checks if the 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 the character is a “unreserved” character in a URI.
Unreserved characters are specified in RFC 3986, section 2.3.
Examples
iex> URI.char_unreserved?(?_)
true
Percent-unescapes a URI.
Examples
iex> URI.decode("http%3A%2F%2Felixir-lang.org")
"http://elixir-lang.org"
Decodes a query string into a map.
Given a query string of 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.
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"}
Decodes a string as “x-www-form-urlencoded”.
Examples
iex> URI.decode_www_form("%3Call+in%2F")
"<all in/"
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(binary, pos_integer) :: :ok
Registers the default port 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(binary, (byte -> boolean)) :: binary
Percent-escapes the given string.
This function accepts a predicate
function as an optional argument; if
passed, this function will be called with each character (byte) in str
as
its argument and should return true
if that character should not be escaped
and left as is.
Example
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 an enumerable into a query string.
Takes an enumerable that enumerates as a list of two-element
tuples (e.g., a map or a keyword list) and returns a string
in the form of key1=value1&key2=value2...
where keys and
values are URL encoded as per encode_www_form/1
.
Keys and values can be any term that implements the String.Chars
protocol, except lists which are explicitly forbidden.
Examples
iex> hd = %{"foo" => 1, "bar" => 2}
iex> URI.encode_query(hd)
"bar=2&foo=1"
iex> query = %{"key" => "value with spaces"}
iex> URI.encode_query(query)
"key=value+with+spaces"
iex> URI.encode_query %{key: [:a, :list]}
** (ArgumentError) encode_query/1 values cannot be lists, got: [:a, :list]
Encodes a string as “x-www-form-urlencoded”.
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"
Parses a well-formed URI reference into its components.
Note this function expects a well-formed URI and does not perform
any validation. See the “Examples” section below for examples of how
URI.parse/1
can be used to parse a wide range of URIs.
This function uses the parsing regular expression as defined in RFC 3986, Appendix B.
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.
If a %URI{}
struct is given to this function, this function returns it
unmodified.
Examples
iex> URI.parse("http://elixir-lang.org/")
%URI{scheme: "http", path: "/", query: nil, fragment: nil,
authority: "elixir-lang.org", userinfo: nil,
host: "elixir-lang.org", port: 80}
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{authority: nil, fragment: nil, host: nil, path: "/foo/bar",
port: nil, query: nil, scheme: nil, userinfo: nil}
iex> URI.parse("foo/bar")
%URI{authority: nil, fragment: nil, host: nil, path: "foo/bar",
port: nil, query: nil, scheme: nil, userinfo: nil}
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.
Examples
iex> URI.query_decoder("foo=1&bar=2") |> Enum.to_list()
[{"foo", "1"}, {"bar", "2"}]
Returns the string representation of the given URI
struct.
iex> URI.to_string(URI.parse("http://google.com"))
"http://google.com"
iex> URI.to_string(%URI{scheme: "foo", host: "bar.baz"})
"foo://bar.baz"