1ncgi(n) CGI Support ncgi(n)
2______________________________________________________________________________
6
8 ncgi - Procedures to manipulate CGI values.
9
11 package require Tcl 8.2
12 package require ncgi ?1.3?
14 ::ncgi::cookie cookie
16 ::ncgi::decode str
18 ::ncgi::empty name
20 ::ncgi::exists name
22 ::ncgi::encode string
24 ::ncgi::header ?type? args
26 ::ncgi::import cginame ?tclname?
28 ::ncgi::importAll args
30 ::ncgi::importFile cmd cginame ?filename?
32 ::ncgi::input ?fakeinput? ?fakecookie?
34 ::ncgi::multipart type query
36 ::ncgi::nvlist
38 ::ncgi::names
40 ::ncgi::parse
42 ::ncgi::parseMimeValue value
44 ::ncgi::query
46 ::ncgi::redirect url
48 ::ncgi::reset query type
50 ::ncgi::setCookie args
52 ::ncgi::setDefaultValue key defvalue
54 ::ncgi::setDefaultValueList key defvaluelist
56 ::ncgi::setValue key value
58 ::ncgi::setValueList key valuelist
60 ::ncgi::type
62 ::ncgi::urlStub ?url?
64 ::ncgi::value key ?default?
66 ::ncgi::valueList key ?default?
68_________________________________________________________________
70
72 The ncgi package provides commands that manipulate CGI values. These
73 are values that come from Web forms and are processed either by CGI
74 scripts or web pages with embedded Tcl code. Use the ncgi package to
75 query these values, set and get cookies, and encode and decode www-url-
76 encoded values.
77 In the simplest case, a CGI script first calls ::ncgi::parse and then
79 calls ::ncgi::value to get different form values. If a CGI value is
80 repeated, you should use ::ncgi::valueList to get back the complete
81 list of values.
82 An alternative to ::ncgi::parse is ::ncgi::input, which has semantics
84 similar to Don Libes' cgi_input procedure. ::ncgi::input restricts
85 repeated CGI values to have names that end with "List". In this case,
86 ::ncgi::value will return the complete list of values, and
87 ::ncgi::input will raise errors if it find repeated form elements with‐
88 out the right name.
89 The ::ncgi::reset procedure can be used in test suites and Web servers
91 to initialize the source of the CGI values. Otherwise the values are
92 read in from the CGI environment.
93 The complete set of procedures is described below.
95 ::ncgi::cookie cookie
97 Return a list of values for cookie, if any. It is possible that
98 more than one cookie with the same name can be present, so this
99 procedure returns a list.
100 ::ncgi::decode str
102 Decode strings in www-url-encoding, which represents special
103 characters with a %xx sequence, where xx is the character code
104 in hex.
105 ::ncgi::empty name
107 Returns 1 if the CGI variable name is not present or has the
108 empty string as its value.
109 ::ncgi::exists name
111 Returns 1 if the CGI variable name is not present.
112 ::ncgi::encode string
114 Encode string into www-url-encoded format.
115 ::ncgi::header ?type? args
117 Output the CGI header to standard output. This emits a Content-
118 Type: header and additional headers based on args, which is a
119 list of header names and header values. The type defaults to
120 "text/html".
121 ::ncgi::import cginame ?tclname?
123 This creates a variable in the current scope with the value of
124 the CGI variable cginame. The name of the variable is tclname,
125 or cginame if tclname is empty (default).
126 ::ncgi::importAll args
128 This imports several CGI variables as Tcl variables. If args is
129 empty, then every CGI value is imported. Otherwise each CGI
130 variable listed in args is imported.
131 ::ncgi::importFile cmd cginame ?filename?
133 This provides information about an uploaded file from a form
134 input field of type file with name cginame. cmd can be one of
135 -server -client, -type or -data.
136 -client cginame
138 returns the filename as sent by the client.
139 -type cginame
141 returns the mime type of the uploaded file.
142 -data cginame
144 returns the contents of the file.
145 -server cginame filename
147 writes the file contents to a local temporary file (or
148 filename if supplied) and returns the name of the file.
149 The caller is responsible for deleting this file after
150 use.
151 ::ncgi::input ?fakeinput? ?fakecookie?
153 This reads and decodes the CGI values from the environment. It
154 restricts repeated form values to have a trailing "List" in
155 their name. The CGI values are obtained later with the
156 ::ncgi::value procedure.
157 ::ncgi::multipart type query
159 This procedure parses a multipart/form-data query. This is used
160 by ::ncgi::nvlist and not normally called directly. It returns
161 an alternating list of names and structured values. Each struc‐
162 ture value is in turn a list of two elements. The first element
163 is meta-data from the multipart/form-data structure. The second
164 element is the form value. If you use ::ncgi::value you just
165 get the form value. If you use ::ncgi::valueList you get the
166 structured value with meta data and the value.
167 The type is the whole Content-Type, including the parameters
169 like boundary. This returns a list of names and values that
170 describe the multipart data. The values are a nested list
171 structure that has some descriptive information first, and the
172 actual form value second. The descriptive information is list
173 of header names and values that describe the content.
174 ::ncgi::nvlist
176 This returns all the query data as a name, value list. In the
177 case of multipart/form-data, the values are structured as
178 described in ::ncgi::multipart.
179 ::ncgi::names
181 This returns all names found in the query data, as a list.
182 ::ncgi::multipart.
183 ::ncgi::parse
185 This reads and decodes the CGI values from the environment. The
186 CGI values are obtained later with the ::ncgi::value procedure.
187 IF a CGI value is repeated, then you should use ::ncgi::val‐
188 ueList to get the complete list of values.
189 ::ncgi::parseMimeValue value
191 This decodes the Content-Type and other MIME headers that have
192 the form of "primary value; param=val; p2=v2" It returns a list,
193 where the first element is the primary value, and the second
194 element is a list of parameter names and values.
195 ::ncgi::query
197 This returns the raw query data.
198 ::ncgi::redirect url
200 Generate a response that causes a 302 redirect by the Web
201 server. The url is the new URL that is the target of the redi‐
202 rect. The URL will be qualified with the current server and
203 current directory, if necessary, to convert it into a full URL.
204 ::ncgi::reset query type
206 Set the query data and Content-Type for the current CGI session.
207 This is used by the test suite and by Web servers to initialize
208 the ncgi module so it does not try to read standard input or use
209 environment variables to get its data. If neither query or type
210 are specified, then the ncgi module will look in the standard
211 CGI environment for its data.
212 ::ncgi::setCookie args
214 Set a cookie value that will be returned as part of the reply.
215 This must be done before ::ncgi::header or ::ncgi::redirect is
216 called in order for the cookie to be returned properly. The
217 args are a set of flags and values:
218 -name name
220 -value value
222 -expires date
224 -path path restriction
226 -domain domain restriction
228 ::ncgi::setDefaultValue key defvalue
230 Set a CGI value if it does not already exists. This affects
231 future calls to ::ncgi::value (but not future calls to
232 ::ncgi::nvlist). If the CGI value already is present, then this
233 procedure has no side effects.
234 ::ncgi::setDefaultValueList key defvaluelist
236 Like ::ncgi::setDefaultValue except that the value already has
237 list structure to represent multiple checkboxes or a multi-
238 selection.
239 ::ncgi::setValue key value
241 Set a CGI value, overriding whatever was present in the CGI
242 environment already. This affects future calls to ::ncgi::value
243 (but not future calls to ::ncgi::nvlist).
244 ::ncgi::setValueList key valuelist
246 Like ::ncgi::setValue except that the value already has list
247 structure to represent multiple checkboxes or a multi-selection.
248 ::ncgi::type
250 Returns the Content-Type of the current CGI values.
251 ::ncgi::urlStub ?url?
253 Returns the current URL, but without the protocol, server, and
254 port. If url is specified, then it defines the URL for the cur‐
255 rent session. That value will be returned by future calls to
256 ::ncgi::urlStub
257 ::ncgi::value key ?default?
259 Return the CGI value identified by key. If the CGI value is not
260 present, then the default value is returned instead. This value
261 defaults to the empty string.
262 If the form value key is repeated, then there are two cases: if
264 ::ncgi::parse was called, then ::ncgi::value only returns the
265 first value associated with key. If ::ncgi::input was called,
266 then ::ncgi::value returns a Tcl list value and key must end in
267 "List" (e.g., "skuList"). In the case of multipart/form-data,
268 this procedure just returns the value of the form element. If
269 you want the meta-data associated with each form value, then use
270 ::ncgi::valueList.
271 ::ncgi::valueList key ?default?
273 Like ::ncgi::value, but this always returns a list of values
274 (even if there is only one value). In the case of multi‐
275 part/form-data, this procedure returns a list of two elements.
276 The first element is meta-data in the form of a parameter, value
277 list. The second element is the form value.
278
280 html
281
283 CGI, cookie, form, html
284ncgi 1.3 ncgi(n)