...

Package url

import "net/url"
Overview
Index
Examples

Overview ▾

Package url parses URLs and implements query escaping.

Index ▾

func PathEscape(s string) string
func PathUnescape(s string) (string, error)
func QueryEscape(s string) string
func QueryUnescape(s string) (string, error)
type Error
    func (e *Error) Error() string
    func (e *Error) Temporary() bool
    func (e *Error) Timeout() bool
    func (e *Error) Unwrap() error
type EscapeError
    func (e EscapeError) Error() string
type InvalidHostError
    func (e InvalidHostError) Error() string
type URL
    func Parse(rawURL string) (*URL, error)
    func ParseRequestURI(rawURL string) (*URL, error)
    func (u *URL) EscapedFragment() string
    func (u *URL) EscapedPath() string
    func (u *URL) Hostname() string
    func (u *URL) IsAbs() bool
    func (u *URL) MarshalBinary() (text []byte, err error)
    func (u *URL) Parse(ref string) (*URL, error)
    func (u *URL) Port() string
    func (u *URL) Query() Values
    func (u *URL) Redacted() string
    func (u *URL) RequestURI() string
    func (u *URL) ResolveReference(ref *URL) *URL
    func (u *URL) String() string
    func (u *URL) UnmarshalBinary(text []byte) error
type Userinfo
    func User(username string) *Userinfo
    func UserPassword(username, password string) *Userinfo
    func (u *Userinfo) Password() (string, bool)
    func (u *Userinfo) String() string
    func (u *Userinfo) Username() string
type Values
    func ParseQuery(query string) (Values, error)
    func (v Values) Add(key, value string)
    func (v Values) Del(key string)
    func (v Values) Encode() string
    func (v Values) Get(key string) string
    func (v Values) Has(key string) bool
    func (v Values) Set(key, value string)

Package files

url.go

func PathEscape 1.8

func PathEscape(s string) string

PathEscape escapes the string so it can be safely placed inside a URL path segment, replacing special characters (including /) with %XX sequences as needed.

func PathUnescape 1.8

func PathUnescape(s string) (string, error)

PathUnescape does the inverse transformation of PathEscape, converting each 3-byte encoded substring of the form "%AB" into the hex-decoded byte 0xAB. It returns an error if any % is not followed by two hexadecimal digits.

PathUnescape is identical to QueryUnescape except that it does not unescape '+' to ' ' (space).

func QueryEscape

func QueryEscape(s string) string

QueryEscape escapes the string so it can be safely placed inside a URL query.

func QueryUnescape

func QueryUnescape(s string) (string, error)

QueryUnescape does the inverse transformation of QueryEscape, converting each 3-byte encoded substring of the form "%AB" into the hex-decoded byte 0xAB. It returns an error if any % is not followed by two hexadecimal digits.

type Error

Error reports an error and the operation and URL that caused it.

type Error struct {
		Op	string
		URL string
		Err error
}

func (*Error) Error

func (e *Error) Error() string

func (*Error) Temporary 1.6

func (e *Error) Temporary() bool

func (*Error) Timeout 1.6

func (e *Error) Timeout() bool

func (*Error) Unwrap 1.13

func (e *Error) Unwrap() error

type EscapeError

type EscapeError string

func (EscapeError) Error

func (e EscapeError) Error() string

type InvalidHostError 1.6

type InvalidHostError string

func (InvalidHostError) Error 1.6

func (e InvalidHostError) Error() string

type URL

A URL represents a parsed URL (technically, a URI reference).

The general form represented is:

[scheme:][//[userinfo@]host][/]path[?query][#fragment]

URLs that do not start with a slash after the scheme are interpreted as:

scheme:opaque[?query][#fragment]

Note that the Path field is stored in decoded form: /%47%6f%2f becomes /Go/. A consequence is that it is impossible to tell which slashes in the Path were slashes in the raw URL and which were %2f. This distinction is rarely important, but when it is, the code should use RawPath, an optional field which only gets set if the default encoding is different from Path.

URL's String method uses the EscapedPath method to obtain the path. See the EscapedPath method for more details.

type URL struct {
		Scheme			string
		Opaque			string		// encoded opaque data
		User				*Userinfo // username and password information
		Host				string		// host or host:port
		Path				string		// path (relative paths may omit leading slash)
		RawPath		 string		// encoded path hint (see EscapedPath method); added in Go 1.5
		ForceQuery	bool			// append a query ('?') even if RawQuery is empty; added in Go 1.7
		RawQuery		string		// encoded query values, without '?'
		Fragment		string		// fragment for references, without '#'
		RawFragment string		// encoded fragment hint (see EscapedFragment method); added in Go 1.15
}
Example

Code:

u, err := url.Parse("http://bing.com/search?q=dotnet")
if err != nil {
		log.Fatal(err)
}
u.Scheme = "https"
u.Host = "google.com"
q := u.Query()
q.Set("q", "golang")
u.RawQuery = q.Encode()
fmt.Println(u)

Output:

https://google.com/search?q=golang
Example (Roundtrip)

Code:

// Parse + String preserve the original encoding.
u, err := url.Parse("https://example.com/foo%2fbar")
if err != nil {
		log.Fatal(err)
}
fmt.Println(u.Path)
fmt.Println(u.RawPath)
fmt.Println(u.String())

Output:

/foo/bar
/foo%2fbar
https://example.com/foo%2fbar

func Parse

func Parse(rawURL string) (*URL, error)

Parse parses a raw url into a URL structure.

The url may be relative (a path, without a host) or absolute (starting with a scheme). Trying to parse a hostname and path without a scheme is invalid but may not necessarily return an error, due to parsing ambiguities.

func ParseRequestURI

func ParseRequestURI(rawURL string) (*URL, error)

ParseRequestURI parses a raw url into a URL structure. It assumes that url was received in an HTTP request, so the url is interpreted only as an absolute URI or an absolute path. The string url is assumed not to have a #fragment suffix. (Web browsers strip #fragment before sending the URL to a web server.)

func (*URL) EscapedFragment 1.15

func (u *URL) EscapedFragment() string

EscapedFragment returns the escaped form of u.Fragment. In general there are multiple possible escaped forms of any fragment. EscapedFragment returns u.RawFragment when it is a valid escaping of u.Fragment. Otherwise EscapedFragment ignores u.RawFragment and computes an escaped form on its own. The String method uses EscapedFragment to construct its result. In general, code should call EscapedFragment instead of reading u.RawFragment directly.

Example

Code:

u, err := url.Parse("http://example.com/#x/y%2Fz")
if err != nil {
		log.Fatal(err)
}
fmt.Println("Fragment:", u.Fragment)
fmt.Println("RawFragment:", u.RawFragment)
fmt.Println("EscapedFragment:", u.EscapedFragment())

Output:

Fragment: x/y/z
RawFragment: x/y%2Fz
EscapedFragment: x/y%2Fz

func (*URL) EscapedPath 1.5

func (u *URL) EscapedPath() string

EscapedPath returns the escaped form of u.Path. In general there are multiple possible escaped forms of any path. EscapedPath returns u.RawPath when it is a valid escaping of u.Path. Otherwise EscapedPath ignores u.RawPath and computes an escaped form on its own. The String and RequestURI methods use EscapedPath to construct their results. In general, code should call EscapedPath instead of reading u.RawPath directly.

Example

Code:

u, err := url.Parse("http://example.com/x/y%2Fz")
if err != nil {
		log.Fatal(err)
}
fmt.Println("Path:", u.Path)
fmt.Println("RawPath:", u.RawPath)
fmt.Println("EscapedPath:", u.EscapedPath())

Output:

Path: /x/y/z
RawPath: /x/y%2Fz
EscapedPath: /x/y%2Fz

func (*URL) Hostname 1.8

func (u *URL) Hostname() string

Hostname returns u.Host, stripping any valid port number if present.

If the result is enclosed in square brackets, as literal IPv6 addresses are, the square brackets are removed from the result.

Example

Code:

u, err := url.Parse("https://example.org:8000/path")
if err != nil {
		log.Fatal(err)
}
fmt.Println(u.Hostname())
u, err = url.Parse("https://[2001:0db8:85a3:0000:0000:8a2e:0370:7334]:17000")
if err != nil {
		log.Fatal(err)
}
fmt.Println(u.Hostname())

Output:

example.org
2001:0db8:85a3:0000:0000:8a2e:0370:7334

func (*URL) IsAbs

func (u *URL) IsAbs() bool

IsAbs reports whether the URL is absolute. Absolute means that it has a non-empty scheme.

Example

Code:

u := url.URL{Host: "example.com", Path: "foo"}
fmt.Println(u.IsAbs())
u.Scheme = "http"
fmt.Println(u.IsAbs())

Output:

false
true

func (*URL) MarshalBinary 1.8

func (u *URL) MarshalBinary() (text []byte, err error)
Example

Code:

u, _ := url.Parse("https://example.org")
b, err := u.MarshalBinary()
if err != nil {
		log.Fatal(err)
}
fmt.Printf("%s\n", b)

Output:

https://example.org

func (*URL) Parse

func (u *URL) Parse(ref string) (*URL, error)

Parse parses a URL in the context of the receiver. The provided URL may be relative or absolute. Parse returns nil, err on parse failure, otherwise its return value is the same as ResolveReference.

Example

Code:

u, err := url.Parse("https://example.org")
if err != nil {
		log.Fatal(err)
}
rel, err := u.Parse("/foo")
if err != nil {
		log.Fatal(err)
}
fmt.Println(rel)
_, err = u.Parse(":foo")
if _, ok := err.(*url.Error); !ok {
		log.Fatal(err)
}

Output:

https://example.org/foo

func (*URL) Port 1.8

func (u *URL) Port() string

Port returns the port part of u.Host, without the leading colon.

If u.Host doesn't contain a valid numeric port, Port returns an empty string.

Example

Code:

u, err := url.Parse("https://example.org")
if err != nil {
		log.Fatal(err)
}
fmt.Println(u.Port())
u, err = url.Parse("https://example.org:8080")
if err != nil {
		log.Fatal(err)
}
fmt.Println(u.Port())

Output:

8080

func (*URL) Query

func (u *URL) Query() Values

Query parses RawQuery and returns the corresponding values. It silently discards malformed value pairs. To check errors use ParseQuery.

Example

Code:

u, err := url.Parse("https://example.org/?a=1&a=2&b=&=3&&&&")
if err != nil {
		log.Fatal(err)
}
q := u.Query()
fmt.Println(q["a"])
fmt.Println(q.Get("b"))
fmt.Println(q.Get(""))

Output:

[1 2]

3

func (*URL) Redacted 1.15

func (u *URL) Redacted() string

Redacted is like String but replaces any password with "xxxxx". Only the password in u.URL is redacted.

Example

Code:

u := &url.URL{
		Scheme: "https",
		User:	 url.UserPassword("user", "password"),
		Host:	 "example.com",
		Path:	 "foo/bar",
}
fmt.Println(u.Redacted())
u.User = url.UserPassword("me", "newerPassword")
fmt.Println(u.Redacted())

Output:

https://user:[email protected]/foo/bar
https://me:[email protected]/foo/bar

func (*URL) RequestURI

func (u *URL) RequestURI() string

RequestURI returns the encoded path?query or opaque?query string that would be used in an HTTP request for u.

Example

Code:

u, err := url.Parse("https://example.org/path?foo=bar")
if err != nil {
		log.Fatal(err)
}
fmt.Println(u.RequestURI())

Output:

/path?foo=bar

func (*URL) ResolveReference

func (u *URL) ResolveReference(ref *URL) *URL

ResolveReference resolves a URI reference to an absolute URI from an absolute base URI u, per RFC 3986 Section 5.2. The URI reference may be relative or absolute. ResolveReference always returns a new URL instance, even if the returned URL is identical to either the base or reference. If ref is an absolute URL, then ResolveReference ignores base and returns a copy of ref.

Example

Code:

u, err := url.Parse("../../..//search?q=dotnet")
if err != nil {
		log.Fatal(err)
}
base, err := url.Parse("http://example.com/directory/")
if err != nil {
		log.Fatal(err)
}
fmt.Println(base.ResolveReference(u))

Output:

http://example.com/search?q=dotnet

func (*URL) String

func (u *URL) String() string

String reassembles the URL into a valid URL string. The general form of the result is one of:

scheme:opaque?query#fragment
scheme://userinfo@host/path?query#fragment

If u.Opaque is non-empty, String uses the first form; otherwise it uses the second form. Any non-ASCII characters in host are escaped. To obtain the path, String uses u.EscapedPath().

In the second form, the following rules apply:

- if u.Scheme is empty, scheme: is omitted.
- if u.User is nil, userinfo@ is omitted.
- if u.Host is empty, host/ is omitted.
- if u.Scheme and u.Host are empty and u.User is nil,
	 the entire scheme://userinfo@host/ is omitted.
- if u.Host is non-empty and u.Path begins with a /,
	 the form host/path does not add its own /.
- if u.RawQuery is empty, ?query is omitted.
- if u.Fragment is empty, #fragment is omitted.
Example

Code:

u := &url.URL{
		Scheme:	 "https",
		User:		 url.UserPassword("me", "pass"),
		Host:		 "example.com",
		Path:		 "foo/bar",
		RawQuery: "x=1&y=2",
		Fragment: "anchor",
}
fmt.Println(u.String())
u.Opaque = "opaque"
fmt.Println(u.String())

Output:

https://me:[email protected]/foo/bar?x=1&y=2#anchor
https:opaque?x=1&y=2#anchor

func (*URL) UnmarshalBinary 1.8

func (u *URL) UnmarshalBinary(text []byte) error
Example

Code:

u := &url.URL{}
err := u.UnmarshalBinary([]byte("https://example.org/foo"))
if err != nil {
		log.Fatal(err)
}
fmt.Printf("%s\n", u)

Output:

https://example.org/foo

type Userinfo

The Userinfo type is an immutable encapsulation of username and password details for a URL. An existing Userinfo value is guaranteed to have a username set (potentially empty, as allowed by RFC 2396), and optionally a password.

type Userinfo struct {
		// contains filtered or unexported fields
}

func User

func User(username string) *Userinfo

User returns a Userinfo containing the provided username and no password set.

func UserPassword

func UserPassword(username, password string) *Userinfo

UserPassword returns a Userinfo containing the provided username and password.

This functionality should only be used with legacy web sites. RFC 2396 warns that interpreting Userinfo this way “is NOT RECOMMENDED, because the passing of authentication information in clear text (such as URI) has proven to be a security risk in almost every case where it has been used.”

func (*Userinfo) Password

func (u *Userinfo) Password() (string, bool)

Password returns the password in case it is set, and whether it is set.

func (*Userinfo) String

func (u *Userinfo) String() string

String returns the encoded userinfo information in the standard form of "username[:password]".

func (*Userinfo) Username

func (u *Userinfo) Username() string

Username returns the username.

type Values

Values maps a string key to a list of values. It is typically used for query parameters and form values. Unlike in the http.Header map, the keys in a Values map are case-sensitive.

type Values map[string][]string
Example

Code:

v := url.Values{}
v.Set("name", "Ava")
v.Add("friend", "Jess")
v.Add("friend", "Sarah")
v.Add("friend", "Zoe")
// v.Encode() == "name=Ava&friend=Jess&friend=Sarah&friend=Zoe"
fmt.Println(v.Get("name"))
fmt.Println(v.Get("friend"))
fmt.Println(v["friend"])

Output:

Ava
Jess
[Jess Sarah Zoe]

func ParseQuery

func ParseQuery(query string) (Values, error)

ParseQuery parses the URL-encoded query string and returns a map listing the values specified for each key. ParseQuery always returns a non-nil map containing all the valid query parameters found; err describes the first decoding error encountered, if any.

Query is expected to be a list of key=value settings separated by ampersands. A setting without an equals sign is interpreted as a key set to an empty value. Settings containing a non-URL-encoded semicolon are considered invalid.

Example

Code:

m, err := url.ParseQuery(`x=1&y=2&y=3`)
if err != nil {
		log.Fatal(err)
}
fmt.Println(toJSON(m))

Output:

{"x":["1"], "y":["2", "3"]}

func (Values) Add

func (v Values) Add(key, value string)

Add adds the value to key. It appends to any existing values associated with key.

func (Values) Del

func (v Values) Del(key string)

Del deletes the values associated with key.

func (Values) Encode

func (v Values) Encode() string

Encode encodes the values into “URL encoded” form ("bar=baz&foo=quux") sorted by key.

func (Values) Get

func (v Values) Get(key string) string

Get gets the first value associated with the given key. If there are no values associated with the key, Get returns the empty string. To access multiple values, use the map directly.

func (Values) Has 1.17

func (v Values) Has(key string) bool

Has checks whether a given key is set.

func (Values) Set

func (v Values) Set(key, value string)

Set sets the key to value. It replaces any existing values.