uri(n) Tcl Uniform Resource Identifier Management uri(n) 







uri - URI utilities








package require Tcl 8.2


package require uri ?1.2.1?


uri::split url ?defaultscheme?


uri::join ?key value?...


uri::resolve base url


uri::isrelative url


uri::geturl url ?options...?


uri::canonicalize uri


uri::register schemeList script












This package contains two parts. First it provides regular
    expressions for a number of url/uri schemes. Second it provides a number of
    commands for manipulating urls/uris and fetching data specified by them. For
    the latter this package analyses the requested url/uri and then dispatches
    it to the appropriate package (http, ftp, ...) for actual fetching.


The package currently does not conform to RFC 2396
    (http://www.rfc-editor.org/rfc/rfc2396.txt), but quite likely should
    be. Patches and other help are welcome.









  

  
uri::split takes an url, decodes it and then returns a list
      of key/value pairs suitable for array set containing the
      constituents of the url. If the scheme is missing from the url it
      defaults to the value of defaultscheme if it was specified, or
      http else. Currently only the schemes http, ftp,
      mailto, urn, news, ldap and file are
      supported by the package itself. See section EXTENDING on how to
      expand that range.
    
The set of constituents of an url (= the set of keys in the
        returned dictionary) is dependent on the scheme of the url. The only key
        which is therefore always present is scheme. For the following
        schemes the constituents and their keys are known:

  







  

  
user, pwd, host, port, path,
      type

  

  
user, pwd, host, port, path,
      query, fragment. The fragment is optional.

  

  
path, host. The host is optional.

  

  
user, host. The host is optional.

  

  
Either message-id or newsgroup-name.









  

  
uri::join takes a list of key/value pairs (generated by
      uri::split, for example) and returns the canonical url they
      represent. Currently only the schemes http, ftp,
      mailto, urn, news, ldap and file are
      supported. See section EXTENDING on how to expand that range.

  

  
uri::resolve resolves the specified url relative to
      base. In other words: A non-relative url is returned
      unchanged, whereas for a relative url the missing parts are taken
      from base and prepended to it. The result of this operation is
      returned. For an empty url the result is base.

  

  
uri::isrelative determines whether the specified url is
      absolute or relative.

  

  
uri::geturl decodes the specified url and then dispatches
      the request to the package appropriate for the scheme found in the url.
      The command assumes that the package to handle the given scheme either has
      the same name as the scheme itself (including possible capitalization)
      followed by ::geturl, or, in case of this failing, has the same
      name as the scheme itself (including possible capitalization). It further
      assumes that whatever package was loaded provides a geturl-command
      in the namespace of the same name as the package itself. This command is
      called with the given url and all given options. Currently
      geturl does not handle any options itself.
    
Note: file-urls are an exception to the rule
        described above. They are handled internally.

    
It is not possible to specify results of the command. They
        depend on the geturl-command for the scheme the request was
        dispatched to.

  

  

  
uri::canonicalize returns the canonical form of a URI. The
      canonical form of a URI is one where relative path specifications, ie. .
      and .., have been resolved.

  

  
uri::register registers the first element of schemeList as a
      new scheme and the remaining elements as aliases for this scheme. It
      creates the namespace for the scheme and executes the script in the
      new namespace. The script has to declare variables containing the regular
      expressions relevant to the scheme. At least the variable
      schemepart has to be declared as that one is used to extend the
      variables keeping track of the registered schemes.










In addition to the commands mentioned above this package provides
    regular expression to recognize urls for a number of url schemes.


For each supported scheme a namespace of the same name as the
    scheme itself is provided inside of the namespace uri containing the
    variable url whose contents are a regular expression to recognize
    urls of that scheme. Additional variables may contain regular expressions
    for parts of urls for that scheme.


The variable uri::schemes contains a list of all supported
    schemes. Currently these are ftp, ldap, file,
    http, gopher, mailto, news, wais and
    prospero.








Extending the range of schemes supported by uri::split and
    uri::join is easy because both commands do not handle the request by
    themselves but dispatch it to another command in the uri namespace
    using the scheme of the url as criterion.


uri::split and uri::join call Split[string
    totitle <scheme>] and Join[string totitle <scheme>]
    respectively.








Original code (regular expressions) by Andreas Kupries.
    Modularisation by Steve Ball, also the split/join/resolve functionality.








This document, and the package it describes, will undoubtedly
    contain bugs and other problems. Please report such in the category
    uri of the Tcllib SF Trackers
    [http://sourceforge.net/tracker/?group_id=12883]. Please also report any
    ideas for enhancements you may have for either package and/or
  documentation.








fetching information, file, ftp, gopher, http, ldap, mailto, news,
    prospero, rfc 2255, rfc 2396, uri, url, wais, www








Networking







  

    1.2.1
    uri