You are looking at historical revision 13234 of this page. It may differ significantly from its current revision.
uri-common
Description
The uri-common library provides simple and easy-to-use parsing and manipulation procedures for URIs using common schemes.
These "common schemes" all have the following rules:
- An empty path after the hostname is considered to be identical to the root path.
- All components are to be fully URI-decoded (so no percent-encoded characters in it).
- The query argument will be in application/x-www-form-urlencoded form.
- The port is automatically determined if it is omitted and the URI scheme is known.
Library Procedures
This library replaces most of the procedures in uri-generic. If you need to work with URIs on the uri-generic level or need to work with both uri-generic and uri-common URI objects, you will have to import and prefix or rename procedures.
Constructors and predicates
These constructors fully decode their arguments, so afterwards it is impossible to distinguish between encoded delimiters and unencoded delimiters. This makes uri-common objects decoding endpoints; no further decoding on the URI level is possible (of course, applications are free to decode further information inside the URI). If for some reason, the original URI is still needed, it can be converted to a uri-generic. However, updating a URI component causes this component's original encoding to be lost, so be careful!
[procedure] (uri-reference STRING) => URIA URI reference is either a URI or a relative reference (RFC 3986, Section 4.1). If the given string's prefix does not match the syntax of a scheme followed by a colon separator, then the given string is parsed as a relative reference.
[procedure] (uri-reference? URI) => BOOLIs the given object a URI reference? All objects created by URI-generic constructors are URI references; they are either URIs or relative references. The constructors below are just more strict checking versions of uri-reference. They all create URI references.
[procedure] (absolute-uri STRING) => URIParses the given string as an absolute URI, in which no fragments are allowed. If no URI scheme is found, or a fragment is detected, this raises an error.
Absolute URIs are defined by RFC 3986 as non-relative URI references without a fragment (RFC 3986, Section 4.2). Absolute URIs can be used as a base URI to resolve a relative-ref against, using uri-relative-to (see below).
[procedure] (absolute-uri? URI) => BOOLIs the given object an absolute URI?
[procedure] (uri? URI) => BOOLIs the given object a URI? URIs are all URI references that include a scheme part. The other type of URI references are relative references.
[procedure] (relative-ref? URI) => BOOLIs the given object a relative reference? Relative references are defined by RFC 3986 as URI references which are not URIs; they contain no URI scheme and can be resolved against an absolute URI to obtain a complete URI using uri-relative-to.
uri-generic and string representation
[procedure] (uri->uri-generic uri-common) => uri-generic[procedure] (uri-generic->uri uri-common) => uri-common
To convert between uri-generic and uri-common objects, use these procedures. As stated above, this will allow you to retrieve the original encoding of the URI components, but once you update a component from the uri-common side, the original encoding is no longer available (the updated value replaces the original value).
[procedure] (uri->string uri-common userinfo) => stringReconstructs the given URI into a string; uses a supplied function LAMBDA USERNAME PASSWORD -> STRING to map the userinfo part of the URI.
Accessors
- <procedure>(uri-scheme uri-common) => symbol</procedure>
- <procedure>(uri-path uri-common) => list</procedure>
- <procedure>(uri-query uri-common) => alist</procedure>
- <procedure>(uri-fragment uri-common) => string</procedure>
- <procedure>(uri-host uri-common) => string</procedure>
- <procedure>(uri-port uri-common) => integer</procedure>
- <procedure>(uri-username uri-common) => string</procedure>
- <procedure>(uri-password uri-common) => string</procedure>
If a component is not defined in the given URI-common, then the corresponding accessor returns #f.
- <procedure>(update-uri URI-common #!key scheme path query fragment host port username password) => URI-common</procedure>
Update the specified keys in the URI-common object in a functional way (ie, it creates a new copy with the modifications).
Reference Resolution
[procedure] (uri-relative-to URI URI) => URIResolve the first URI as a reference relative to the second URI, returning a new URI (RFC 3986, Section 5.2.2).
[procedure] (uri-relative-from URI URI) => URIConstructs a new, possibly relative, URI which represents the location of the first URI with respect to the second URI.
(use uri-common)
(uri->string (uri-relative-to (uri-reference "../qux") (uri-reference "http://example.com/foo/bar/")))
"http://example.com/foo/qux"
(use uri-common)
(uri->string (uri-relative-from (uri-reference "http://example.com/foo/qux") (uri-reference "http://example.com/foo/bar/")))
"../qux"
Query encoding and decoding
- <parameter>(form-urlencoded-separator [char-set/char/string])</parameter>
- <procedure>(form-urlencode alist #!key (separator (form-urlencoded-separator))) => string</procedure>
- <procedure>(form-urldecode string #!key (separator (form-urlencoded-separator))) => alist</procedure>
Encode or decode an alist using the encoding corresponding to the form-urlencoded media type, using the given separator character(s).
When encoding, if separator is a string, the first character will be used as the separator in the resulting querystring. If it is a char-set, it will be converted to a string and its first character will be taken. In either case, all of these characters are encoded if they occur inside the key/value pairs.
When decoding, any character in the set (or string) will be seen as a separator.
The separator defaults to the string ";&". This means that either semicolons or ampersands are allowed as separators when decoding an URI string, but semicolons are used when generating strings.
If you would like to use a different separator, you should parameterize all calls to procedures that return an uri-common object.
Normalization
[procedure] (uri-normalize-case URI) => URIURI case normalization (RFC 3986 section 6.2.2.1)
[procedure] (uri-normalize-path-segments URI) => URIURI path segment normalization (RFC 3986 section 6.2.2.3)
Requires
Version History
- trunk Add predicates for URIs, absolute URIs and relative references, matching the ones in uri-generic.
- 0.1 Initial Release
License
Copyright 2008-2009 Peter Bex All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. Neither the name of the author nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.