TWiki operates by creating a singleton object (known as the Session
object) that acts as a point of reference for all the different
modules in the system. This package is the class for this singleton,
and also contains the vast bulk of the basic constants and the per-
site configuration mechanisms.
Global variables are avoided wherever possible to avoid problems
with CGI accelerators such as mod_perl.
Public Data members
request Pointer to the TWiki::Request
response Pointer to the TWiki::Respose
context Hash of context ids
moved: loginManager TWiki::LoginManager singleton (moved to TWiki::Users)
plugins TWiki::Plugins singleton
prefs TWiki::Prefs singleton
remoteUser Login ID when using ApacheLogin. Maintained for compatibility only, do not use.
requestedWebName Name of web found in URL path or web URL parameter
sandbox TWiki::Sandbox singleton
scriptUrlPath URL path to the current script. May be dynamically extracted from the URL path if {GetScriptUrlFromCgi}. Only required to support {GetScriptUrlFromCgi} and not consistently used. Avoid.
security TWiki::Access singleton
SESSION_TAGS Hash of TWiki variables whose value is specific to the current request.
store TWiki::Store singleton
topicName Name of topic found in URL path or topic URL parameter
urlHost Host part of the URL (including the protocol) determined during intialisation and defaulting to {DefaultUrlHost}
user Unique user ID of logged-in user
users TWiki::Users singleton
webName Name of web found in URL path, or web URL parameter, or {UsersWebName}
Write a complete HTML page with basic header to the browser.
$text is the text of the page body (<html> to </html> if it's HTML)
$pageType - May be "edit", which will cause headers to be generated that force caching for 24 hours, to prevent BackFromPreviewLosesText bug, which caused data loss with IE5 and IE6.
$contentType - page content type | text/html
$status - page status | 200 OK
This method removes noautolink and nop tags before outputting the page unless
$contentType is text/plain.
$pageType - May be "edit", which will cause headers to be generated that force caching for 24 hours, to prevent BackFromPreviewLosesText bug, which caused data loss with IE5 and IE6.
$contentType - page content type | text/html
$status - page status | 200 OK
Implements the post-Dec2001 release plugin API, which requires the
writeHeaderHandler in plugin to return a string of HTTP headers, CR/LF
delimited. Filters any illegal headers. Plugin headers will override
core settings.
Does not add a Content-length header.
$action_redirectto - (optional) redirect to where ?redirectto= points to (if it's valid)
$viaCache - forcibly cache a redirect CGI query. It cuts off all the params in a GET url and replace with a "?$cache=..." param.
Redirects the request to $url, unless
It is overridden by a plugin declaring a redirectCgiQueryHandler.
$session->{request} is undef or
$query->param('noredirect') is set to a true value.
Thus a redirect is only generated when in a CGI context.
Normally this method will ignore parameters to the current query. Sometimes,
for example when redirecting to a login page during authentication (and then
again from the login page to the original requested URL), you want to make
sure all parameters are passed on, and for this $passthrough should be set to
true. In this case it will pass all parameters that were passed to the
current query on to the redirect target. If the request_method for the
current query was GET, then all parameters will be passed by encoding them
in the URL (after ?). If the request_method was POST, then there is a risk the
URL would be too big for the receiver, so it caches the form data and passes
over a cache reference in the redirect GET.
NOTE: Passthrough is only meaningful if the redirect target is on the same
server. "$viaCache" is meaningful only if "$action_redirectto" is false and
"$passthru" is true.
Caches the current query in the params cache, and returns a rewritten
query string for the cache to be picked up again on the other side of a
redirect.
We can't encode post params into a redirect, because they may exceed the
size of the GET request. So we cache the params, and reload them when the
redirect target is reached.
STATIC Check for a valid web name. If $system is true, then
system web names are considered valid (names starting with _)
otherwise only user web names are valid
If $TWiki::cfg{EnableHierarchicalWebs} is off, it will also return false
when a nested web name is passed to it.
Returns the following hash reference such as this:
('', undef)
and this:
('slave', { # master site data
siteName => 'na',
webScriptUrlTmpl => 'http://twiki.example.com/cgi-bin//Web',
scriptSuffix => '',
webViewUrl => 'http://twiki.example.com/Web',
})
The first value is the mode of the web: either 'local', 'master', 'slave',
or 'read-only'. The second value is defined only when the master site is
defined for the web.
Returns the URL to a TWiki script, providing the web and topic as
"path info" parameters. The result looks something like this:
"http://host/twiki/bin/$script/$web/$topic".
... - an arbitrary number of name,value parameter pairs that will be url-encoded and added to the url. The special parameter name '#' is reserved for specifying an anchor. e.g. getScriptUrl('x','y','view','#'=>'XXX',a=>1,b=>2) will give .../view/x/y?a=1&b=2#XXX
If $absolute is set, generates an absolute URL. $absolute is advisory only;
TWiki can decide to generate absolute URLs (for example when run from the
command-line) even when relative URLs have been requested.
The default script url is taken from {ScriptUrlPath}, unless there is
an exception defined for the given script in {ScriptUrlPaths}. Both
{ScriptUrlPath} and {ScriptUrlPaths} may be absolute or relative URIs. If
they are absolute, then they will always generate absolute URLs. if they
are relative, then they will be converted to absolute when required (e.g.
when running from the command line, or when generating rss). If
$script is not given, absolute URLs will always be generated.
If either the web or the topic is defined, will generate a full url
(including web and topic). Otherwise will generate only up to the script
name. An undefined web will default to the main web name.
The returned URL takes ReadOnlyAndMirrorWebs into account.
If the specified $web is slave on this site, with the scripts
edit, save, attach, upload, and rename, this method returns
the URLs on the master site because it does not make sense to execute
those scripts on the master site of the web.
Even with the other scripts, you may need to get the URLs on the master site.
You can get those URLs by providing $master => 1 as a name value pair.
Composes a pub url. If $absolute is set, returns an absolute URL.
If $absolute is set, generates an absolute URL. $absolute is advisory only;
TWiki can decide to generate absolute URLs (for example when run from the
command-line) even when relative URLs have been requested.
$web, $topic and $attachment are optional. A partial URL path will be
generated if one or all is not given.
Format an icon based on name and format parameter. The format parameter handles
these variables (with example):
$name: Name of icon ('home')
$type: Type of icon ('gif')
$filename: Icon filename ('home.gif')
$web: Web where icon is located ('TWiki')
$topic: Topic where icon is located ('TWikiDocGraphics')
$description: Icon description ('Home')
$width: Width of icon ('16')
$height: Height of icon ('16')
$img: Full img tag of icon ('')
$url: URL of icon ('http://example.com/pub/TWiki/TWikiDocGraphics/home.gif')
$urlpath: URL path of icon ('/pub/TWiki/TWikiDocGraphics/home.gif')
The optional default parameter specifies the icon name in case the icon is not defined.
Leave empty if you assume icon files exist in the default location.
Normalize a Web.TopicName
See TWikiFuncDotPm for a full specification of the expansion (not duplicated
here)
WARNING if there is no web specification (in the web or topic parameters)
the web defaults to $TWiki::cfg{UsersWebName}. If there is no topic
specification, or the topic is '0', the topic defaults to the web home topic
name.
Constructs a new TWiki object. Parameters are taken from the query object.
$loginName is the login username (not the wikiname) of the user you want to be logged-in if none is available from a session or browser. Used mainly for side scripts and debugging.
$query the TWiki::Request query (may be undef, in which case an empty query is used)
\%initialContext - reference to a hash containing context name=value pairs to be pre-installed in the context hash
Prints date, time, and contents $text to $TWiki::cfg{WarningFileName}, typically
'warnings.txt'. Use for warnings and errors that may require admin
intervention. Use this for defensive programming warnings (e.g. assertions).
Format an error for inline inclusion in rendered output. The message string
is obtained from the template 'oops'.$template, and the DEF $def is
selected. The parameters (...) are used to populate %PARAM1%..%PARAMn%
Generic parser for sections within a topic. Sections are delimited
by STARTSECTION and ENDSECTION, which may be nested, overlapped or
otherwise abused. The parser builds an array of sections, which is
ordered by the order of the STARTSECTION within the topic. It also
removes all the SECTION tags from the text, and returns the text
and the array of sections.
Each section is a TWiki::Attrs object, which contains the attributes
{type, name, start, end}
where start and end are character offsets in the
string after all section tags have been removed. All sections
are required to be uniquely named; if a section is unnamed, it
will be given a generated name. Sections may overlap or nest.
See test/unit/Fn_SECTION.pm for detailed testcases that
round out the spec.
$user - This is the user expanded in e.g. %USERNAME. Optional, defaults to logged-in user.
$web - name of web, optional
$topic - name of topic, optional
Expand limited set of variables during topic creation. These are variables
expected in templates that must be statically expanded in new content.
# SMELL: no plugin handler
Escape special characters to HTML numeric entities. This is not a generic
encoding, it is tuned specifically for use in TWiki.
HTML4.0 spec:
"Certain characters in HTML are reserved for use as markup and must be
escaped to appear literally. The "<" character may be represented with
an entity, <. Similarly, ">"
is escaped as >, and "&" is escaped
as &. If an attribute value contains a
double quotation mark and is delimited by double quotation marks, then the
quote should be escaped as ".
Other entities exist for special characters that cannot easily be entered
with some keyboards..."
This method encodes HTML special and any non-printable ascii
characters (except for \n and \r) using numeric entities.
FURTHER this method also encodes characters that are special in TWiki
meta-language.
$extras is an optional param that may be used to include additional
characters in the set of encoded characters. It should be a string
containing the additional chars.
For attachments, URL-encode specially to 'freeze' any characters >127 in the
site charset (e.g. ISO-8859-1 or KOI8-R), by doing URL encoding into native
charset ($siteCharset) - used when generating attachment URLs, to enable the
web server to serve attachments, including images, directly.
This encoding is required to handle the cases of:
- browsers that generate UTF-8 URLs automatically from site charset URLs - now quite common
- web servers that directly serve attachments, using the site charset for
filenames, and cannot convert UTF-8 URLs into site charset filenames
The aim is to prevent the browser from converting a site charset URL in the web
page to a UTF-8 URL, which is the default. Hence we 'freeze' the URL into the
site character set through URL encoding.
In two cases, no URL encoding is needed: For EBCDIC mainframes, we assume that
site charset URLs will be translated (outbound and inbound) by the web server to/from an
EBCDIC character set. For sites running in UTF-8, there's no need for TWiki to
do anything since all URLs and attachment filenames are already in UTF-8.
Encode by converting characters that are illegal in URLs to
their %NN equivalents. This method is used for encoding
strings that must be embedded verbatim in URLs; it cannot
be applied to URLs themselves, as it escapes reserved
characters such as = and ?.
RFC 1738, Dec. '94:
...Only alphanumerics [0-9a-zA-Z], the special
characters $-_.+!*'(), and reserved characters used for their
reserved purposes may be used unencoded within a URL.
Reserved characters are $&+,/:;=?@ - these are also encoded by
this method.
This URL-encoding handles all character encodings including ISO-8859-*,
KOI8-R, EUC-* and UTF-8.
This may not handle EBCDIC properly, as it generates an EBCDIC URL-encoded
URL, but mainframe web servers seem to translate this outbound before it hits browser
- see CGI::Util::escape for another approach.
Returns 1 if $value is true, and 0 otherwise. "true" means set to
something with a Perl true value, with the special cases that "off",
"false" and "no" (case insensitive) are forced to false. Leading and
trailing spaces in $value are ignored.
If the value is undef, then $default is returned. If $default is
not specified it is taken as 0.
Spaces out a wiki word by inserting a string between each word component.
Word component boundaries are transitions from lowercase to uppercase or numeric,
from numeric to uppercase or lowercase, and from uppercase to numeric characters.
Parameter $sep defines the separator between the word components, the default is a space.
Example: "ABC2015ProjectCharter" results in "ABC 2015 Project Charter"
Expands variables by replacing the variables with their
values. Some example variables: %TOPIC%, %SCRIPTURL%,
%WIKINAME%, etc.
$web and $incs are passed in for recursive include expansion. They can
safely be undef.
The rules for tag expansion are:
Tags are expanded left to right, in the order they are encountered.
Tags are recursively expanded as soon as they are encountered - the algorithm is inherently single-pass
A tag is not "encountered" until the matching }% has been seen, by which time all tags in parameters will have been expanded
Tag expansions that create new tags recursively are limited to a set number of hierarchical levels of expansion
Add the context id $id into the set of active contexts. The $val
can be anything you like, but should always evaluate to boolean
TRUE.
An example of the use of contexts is in the use of tag
expansion. The commonTagsHandler in plugins is called every
time tags need to be expanded, and the context of that expansion
is signalled by the expanding module using a context id. So the
forms module adds the context id "form" before invoking common
tags expansion.
Contexts are not just useful for tag expansion; they are also
relevant when rendering.
Contexts are intended for use mainly by plugins. Core modules can
use $session->inContext( $id ) to determine if a context is active.
Processes %VARIABLE%, and %TOC% syntax; also includes
'commonTagsHandler' plugin hook.
Returns the text of the topic, after file inclusion, variable substitution,
table-of-contents generation, and any plugin changes from commonTagsHandler.
$meta may be undef when, for example, expanding templates, or one-off strings
at a time when meta isn't available.
Add $html to the HEAD tag of the page currently being generated.
Note that TWiki variables may be used in the HEAD. They will be expanded
according to normal variable expansion rules.
%ADDTOHEAD%
You can write == in a topic or template. This variable accepts the following parameters:
_DEFAULT optional, id of the head block. Used to generate a comment in the output HTML.
text optional, text to use for the head block. Mutually exclusive with topic.
topic optional, full TWiki path name of a topic that contains the full text to use for the head block. Mutually exclusive with text. Example: topic="TWiki.MyTopic".
requires optional, comma-separated list of id's of other head blocks this one depends on.
%ADDTOHEAD% expands in-place to the empty string, unless there is an error in which case the variable expands to an error string.
Use %RENDERHEAD% to generate the sorted head tags.
%RENDERHEAD%
... should be written where you want the sorted head tags to be generated. This will normally be in a template. The variable expands to a sorted list of the head blocks added up to the point the RENDERHEAD variable is expanded. Each expanded head block is preceded by an HTML comment that records the ID of the head block.
Head blocks are sorted to satisfy all their requires constraints.
The output order of blocks with no requires value is undefined. If cycles
exist in the dependency order, the cycles will be broken but the resulting
order of blocks in the cycle is undefined.
Return value: ( $topicName, $webName, $TWiki::cfg{ScriptUrlPath}, $userName, $TWiki::cfg{DataDir} )
Static method to construct a new singleton session instance.
It creates a new TWiki and sets the Plugins $SESSION variable to
point to it, so that TWiki::Func methods will work.
This method is DEPRECATED but is maintained for script compatibility.
Note that $theUrl, if specified, must be identical to $query->url()
Returns the entire contents of the given file, which can be specified in any
format acceptable to the Perl open() function. Fast, but inherently unsafe.
WARNING: Never, ever use this for accessing topics or attachments! Use the
Store API for that. This is for global control files only, and should be
used only if there is absolutely no alternative.
Returns the MIME type corresponding to the extension of the $filename based on
the file specified by {MimeTypesFileName}. If there is no extension or the
extension is not found in the {MimeTypesFileName} file, 'text/plain' is
returned.
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