# `uritools` — RFC 3986 compliant replacement for `urlparse`

This module defines RFC 3986 compliant replacements for the most commonly used functions of the Python 2.7 Standard Library `urlparse` and Python 3 `urllib.parse` modules.

    >>> from uritools import urisplit, uriunsplit, urijoin, uridefrag
    >>> parts = urisplit('foo://user@example.com:8042/over/there?name=ferret#nose')
    >>> parts
    SplitResult(scheme='foo', authority='user@example.com:8042',
                path='/over/there', query='name=ferret', fragment='nose')
    >>> parts.scheme
    'foo'
    >>> parts.authority
    'user@example.com:8042'
    >>> parts.userinfo
    'user'
    >>> parts.host
    'example.com'
    >>> parts.port
    '8042'
    >>> uriunsplit(parts[:3] + ('name=swallow&type=African', 'beak'))
    'foo://user@example.com:8042/over/there?name=swallow&type=African#beak'
    >>> urijoin('http://www.cwi.nl/~guido/Python.html', 'FAQ.html')
    'http://www.cwi.nl/~guido/FAQ.html'
    >>> uridefrag('http://pythonhosted.org/uritools/index.html#constants')
    DefragResult(uri='http://pythonhosted.org/uritools/index.html',
                 fragment='constants')

For various reasons, the Python 2 `urlparse` module is not compliant with current Internet standards, does not include Unicode support, and is generally unusable with proprietary URI schemes. Python 3’s `urllib.parse` improves on Unicode support, but the other issues still remain. As stated in Lib/urllib/parse.py:

    FC 3986 is considered the current standard and any future changes
    to urlparse module should conform with it.  The urlparse module is
    currently not entirely compliant with this RFC due to defacto
    scenarios for parsing, and for backward compatibility purposes,
    some parsing quirks from older RFCs are retained.

This module aims to provide fully RFC 3986 compliant replacements for the most commonly used functions found in `urlparse` and `urllib.parse`, plus additional functions for conveniently composing URIs from their individual components.

See also

RFC 3986 - Uniform Resource Identifier (URI): Generic Syntax
  The current Internet standard (STD66) defining URI syntax, to which any changes to `uritools` should conform. If deviations are observed, the module’s implementation should be changed, even if this means breaking backward compatiblity.

## URI Decomposition

`uritools.``uridefrag`(uristring)

  Remove an existing fragment component from a URI string.

  The return value is an instance of a subclass of `collections.namedtuple` with the following read-only attributes:

  Attribute | Index | Value
  --- | --- | ---
  `uri` | 0 | Absolute URI or relative URI reference without the fragment identifier
  `fragment` | 1 | Fragment identifier, or `None` if not present

`uritools.``urisplit`(uristring)

  Split a well-formed URI string into a tuple with five components corresponding to a URI’s general structure:

      <scheme>://<authority>/<path>?<query>#<fragment>

  The return value is an instance of a subclass of `collections.namedtuple` with the following read-only attributes:

  Attribute | Index | Value
  --- | --- | ---
  `scheme` | 0 | URI scheme, or `None` if not present
  `authority` | 1 | Authority component, or `None` if not present
  `path` | 2 | Path component, always present but may be empty
  `query` | 3 | Query component, or `None` if not present
  `fragment` | 4 | Fragment identifier, or `None` if not present
  `userinfo` |  | Userinfo subcomponent of authority, or `None` if not present
  `host` |  | Host subcomponent of authority, or `None` if not present
  `port` |  | Port subcomponent of authority as a (possibly empty) string, or `None` if not present

## URI Composition

`uritools.``uricompose`(scheme=None, authority=None, path=u'', query=None, fragment=None, userinfo=None, host=None, port=None, encoding=u'utf-8')

  Compose a URI string from its individual components.

  authority may be a Unicode string, `bytes` object, or a three-item iterable specifying userinfo, host and port subcomponents. If both authority and any of the userinfo, host or port keyword arguments are given, the keyword argument will override the corresponding authority subcomponent.

  If query is a mapping object or a sequence of two-element tuples, it will be converted to a string of name=value pairs seperated by &.

  The returned value is of type `str`.

`uritools.``urijoin`(base, ref, strict=False)

  Convert a URI reference relative to a base URI to its target URI string.

  If strict is `False`, a scheme in the reference is ignored if it is identical to the base URI’s scheme.

`uritools.``uriunsplit`(parts)

  Combine the elements of a five-item iterable into a URI string.

## URI Encoding

`uritools.``uridecode`(uristring, encoding='utf-8', errors='strict')

  Decode a URI string or string component.

  If encoding is set to `None`, return the percent-decoded uristring as a `bytes` object. Otherwise, replace any percent-encodings and decode uristring using the codec registered for encoding, returning a Unicode string.

`uritools.``uriencode`(uristring, safe='', encoding='utf-8', errors='strict')

  Encode a URI string or string component.

  If uristring is a `bytes` object, replace any characters not in `UNRESERVED` or safe with their corresponding percent-encodings and return the result as a `bytes` object. Otherwise, encode uristring using the codec registered for encoding before replacing any percent encodings.

  Note that uristring may be either a Unicode string or a `bytes` object, while safe must be a `bytes` object containg ASCII characters only.

## Character Constants

`uritools.``GEN_DELIMS`

  A string containing all general delimiting characters specified in RFC 3986.

`uritools.``RESERVED`

  A string containing all reserved characters specified in RFC 3986.

`uritools.``SUB_DELIMS`

  A string containing all subcomponent delimiting characters specified in RFC 3986.

`uritools.``UNRESERVED`

  A string containing all unreserved characters specified in RFC 3986.

## Structured Parse Results

The result objects from the `uridefrag()` and `urisplit()` functions are instances of subclasses of `collections.namedtuple`. These objects contain the attributes described in the function documentation, as well as some additional convenience methods.

class `uritools.``DefragResult`

  Class to hold `uridefrag()` results.

  `getfragment`(default=None, encoding=u'utf-8', errors=u'strict')

    Return the decoded fragment identifier, or default if the original URI did not contain a fragment component.

  `geturi`()

    Return the recombined version of the original URI as a string.

class `uritools.``SplitResult`

  Base class to hold `urisplit()` results.

  `getfragment`(default=None, encoding=u'utf-8', errors=u'strict')

    Return the decoded fragment identifier, or default if the original URI did not contain a fragment component.

  `gethost`(default=None)

    Return the decoded host subcomponent of the URI authority as a string or an `ipaddress` address object, or default if the original URI did not contain a host.

  `getpath`(encoding=u'utf-8', errors=u'strict')

    Return the normalized decoded URI path.

  `getport`(default=None)

    Return the port subcomponent of the URI authority as an `int`, or default if the original URI did not contain a port or if the port was empty.

  `getquery`(default=None, encoding=u'utf-8', errors=u'strict')

    Return the decoded query string, or default if the original URI did not contain a query component.

  `getquerydict`(encoding=u'utf-8', errors=u'strict')

    Split the query component into individual name=value pairs and return a dictionary of query variables. The dictionary keys are the unique query variable names and the values are lists of values for each name.

  `getquerylist`(encoding=u'utf-8', errors=u'strict')

    Split the query component into individual name=value pairs and return a list of (name, value) tuples.

  `getscheme`(default=None)

    Return the URI scheme in canonical (lowercase) form, or default if the original URI did not contain a scheme component.

  `geturi`()

    Return the re-combined version of the original URI as a string.

  `getuserinfo`(default=None, encoding=u'utf-8', errors=u'strict')

    Return the decoded userinfo subcomponent of the URI authority, or default if the original URI did not contain a userinfo field.

  `transform`(ref, strict=False)

    Transform a URI reference relative to self into a `SplitResult` representing its target URI.