.TH httpd_util 3erl "inets 7.3.2" "Ericsson AB" "Erlang Module Definition"
.SH NAME
httpd_util \- Miscellaneous utility functions to be used when implementing 
  Erlang web server API modules.
.SH DESCRIPTION
.LP
This module provides the Erlang web server API module programmer with miscellaneous utility functions\&.
.SH EXPORTS
.LP
.B
convert_request_date(DateString) -> ErlDate|bad_date
.br
.RS
.LP
Types:

.RS 3
DateString = string()
.br
ErlDate = calendar:datetime() 
.br
.RE
.RE
.RS
.LP
\fIconvert_request_date/1\fR\& converts \fIDateString\fR\& to the Erlang date format\&. \fIDateString\fR\& must be in one of the three date formats defined in RFC 2616\&.
.RE

.LP
.B
create_etag(FileInfo) -> Etag
.br
.RS
.LP
Types:

.RS 3
FileInfo = file_info()
.br
Etag = string()
.br
.RE
.RE
.RS
.LP
\fIcreate_etag/1\fR\& calculates the Etag for a file from its size and time for last modification\&. \fIFileInfo\fR\& is a record defined in \fIkernel/include/file\&.hrl\fR\&\&.
.RE

.LP
.B
day(NthDayOfWeek) -> DayOfWeek
.br
.RS
.LP
Types:

.RS 3
NthDayOfWeek = 1-7
.br
DayOfWeek = string()
.br
.RE
.RE
.RS
.LP
\fIday/1\fR\& converts the day of the week (\fINthDayOfWeek\fR\&) from an integer (1-7) to an abbreviated string, that is:
.LP
1 = "Mon", 2 = "Tue", \&.\&.\&., 7 = "Sat"\&.
.RE

.LP
.B
decode_hex(HexValue) -> DecValue
.br
.RS
.LP
Types:

.RS 3
HexValue = DecValue = string()
.br
.RE
.RE
.RS
.LP
Converts the hexadecimal value \fIHexValue\fR\& into its decimal equivalent (\fIDecValue\fR\&)\&.
.RE

.LP
.B
flatlength(NestedList) -> Size
.br
.RS
.LP
Types:

.RS 3
NestedList = list()
.br
Size = integer()
.br
.RE
.RE
.RS
.LP
\fIflatlength/1\fR\& computes the size of the possibly nested list \fINestedList\fR\&, which can contain binaries\&.
.RE

.LP
.B
hexlist_to_integer(HexString) -> Number
.br
.RS
.LP
Types:

.RS 3
Number = integer()
.br
HexString = string()
.br
.RE
.RE
.RS
.LP
\fIhexlist_to_integer\fR\& converts the hexadecimal value of \fIHexString\fR\& to an integer\&.
.RE

.LP
.B
integer_to_hexlist(Number) -> HexString
.br
.RS
.LP
Types:

.RS 3
Number = integer()
.br
HexString = string()
.br
.RE
.RE
.RS
.LP
\fIinteger_to_hexlist/1\fR\& returns a string representing \fINumber\fR\& in a hexadecimal form\&.
.RE

.LP
.B
lookup(ETSTable,Key) -> Result
.br
.B
lookup(ETSTable,Key,Undefined) -> Result
.br
.RS
.LP
Types:

.RS 3
ETSTable = ets_table()
.br
Key = term()
.br
Result = term() | undefined | Undefined
.br
Undefined = term()
.br
.RE
.RE
.RS
.LP
\fIlookup\fR\& extracts \fI{Key,Value}\fR\& tuples from \fIETSTable\fR\& and returns the \fIValue\fR\& associated with \fIKey\fR\&\&. If \fIETSTable\fR\& is of type \fIbag\fR\&, only the first \fIValue\fR\& associated with \fIKey\fR\& is returned\&. \fIlookup/2\fR\& returns \fIundefined\fR\& and \fIlookup/3\fR\& returns \fIUndefined\fR\& if no \fIValue\fR\& is found\&.
.RE

.LP
.B
lookup_mime(ConfigDB,Suffix)
.br
.B
lookup_mime(ConfigDB,Suffix,Undefined) -> MimeType
.br
.RS
.LP
Types:

.RS 3
ConfigDB = ets_table()
.br
Suffix = string()
.br
MimeType = string() | undefined | Undefined
.br
Undefined = term()
.br
.RE
.RE
.RS
.LP
\fIlookup_mime\fR\& returns the MIME type associated with a specific file suffix as specified in the file \fImime\&.types\fR\& (located in the config directory)\&.
.RE

.LP
.B
lookup_mime_default(ConfigDB,Suffix)
.br
.B
lookup_mime_default(ConfigDB,Suffix,Undefined) -> MimeType
.br
.RS
.LP
Types:

.RS 3
ConfigDB = ets_table()
.br
Suffix = string()
.br
MimeType = string() | undefined | Undefined
.br
Undefined = term()
.br
.RE
.RE
.RS
.LP
\fIlookup_mime_default\fR\& returns the MIME type associated with a specific file suffix as specified in the \fImime\&.types\fR\& file (located in the config directory)\&. If no appropriate association is found, the value of \fIDefaultType\fR\& is returned\&.
.RE

.LP
.B
message(StatusCode,PhraseArgs,ConfigDB) -> Message
.br
.RS
.LP
Types:

.RS 3
StatusCode = 301 | 400 | 403 | 404 | 500 | 501 | 504
.br
PhraseArgs = term()
.br
ConfigDB = ets_table
.br
Message = string()
.br
.RE
.RE
.RS
.LP
\fImessage/3\fR\& returns an informative HTTP 1\&.1 status string in HTML\&. Each \fIStatusCode\fR\& requires a specific \fIPhraseArgs\fR\&:
.RS 2
.TP 2
.B
\fI301\fR\&:
\fIstring()\fR\&: A URL pointing at the new document position\&.
.TP 2
.B
\fI400 | 401 | 500\fR\&:
\fInone\fR\& (no \fIPhraseArgs\fR\&)\&.
.TP 2
.B
\fI403 | 404\fR\&:
\fIstring()\fR\&: A \fIRequest-URI\fR\& as described in RFC 2616\&.
.TP 2
.B
\fI501\fR\&:
\fI{Method,RequestURI,HTTPVersion}\fR\&: The HTTP \fIMethod\fR\&, \fIRequest-URI\fR\&, and \fIHTTP-Version\fR\& as defined in RFC 2616\&.
.TP 2
.B
\fI504\fR\&:
\fIstring()\fR\&: A string describing why the service was unavailable\&.
.RE
.RE

.LP
.B
month(NthMonth) -> Month
.br
.RS
.LP
Types:

.RS 3
NthMonth = 1-12
.br
Month = string()
.br
.RE
.RE
.RS
.LP
\fImonth/1\fR\& converts the month \fINthMonth\fR\& as an integer (1-12) to an abbreviated string, that is:
.LP
1 = "Jan", 2 = "Feb", \&.\&.\&., 12 = "Dec"\&.
.RE

.LP
.B
multi_lookup(ETSTable,Key) -> Result
.br
.RS
.LP
Types:

.RS 3
ETSTable = ets_table()
.br
Key = term()
.br
Result = [term()]
.br
.RE
.RE
.RS
.LP
\fImulti_lookup\fR\& extracts all \fI{Key,Value}\fR\& tuples from an \fIETSTable\fR\& and returns \fIall\fR\& \fIValues\fR\& associated with \fIKey\fR\& in a list\&.
.RE

.LP
.B
reason_phrase(StatusCode) -> Description
.br
.RS
.LP
Types:

.RS 3
StatusCode = 100| 200 | 201 | 202 | 204 | 205 | 206 | 300 | 301 | 302 | 303 | 304 | 400 | 401 | 402 | 403 | 404 | 405 | 406 | 410 411 | 412 | 413 | 414 415 | 416 | 417 | 500 | 501 | 502 | 503 | 504 | 505
.br
Description = string()
.br
.RE
.RE
.RS
.LP
\fIreason_phrase\fR\& returns \fIDescription\fR\& of an HTTP 1\&.1 \fIStatusCode\fR\&, for example, 200 is "OK" and 201 is "Created"\&. For more information, see RFC 2616\&.
.RE

.LP
.B
rfc1123_date() -> RFC1123Date
.br
.B
rfc1123_date(Date) -> RFC1123Date
.br
.RS
.LP
Types:

.RS 3
 Date = calendar:datetime()
.br
RFC1123Date = string()
.br
.RE
.RE
.RS
.LP
\fIrfc1123_date/0\fR\& returns the current date in RFC 1123 format\&. \fIrfc_date/1\fR\& converts the date in the Erlang format to the RFC 1123 date format\&.
.RE

.LP
.B
split(String,RegExp,N) -> SplitRes
.br
.RS
.LP
Types:

.RS 3
String = RegExp = string()
.br
SplitRes = {ok, FieldList} | {error, errordesc()}
.br
Fieldlist = [string()]
.br
N = integer
.br
.RE
.RE
.RS
.LP
\fIsplit/3\fR\& splits \fIString\fR\& in \fIN\fR\& chunks using \fIRegExp\fR\&\&. \fIsplit/3\fR\& is equivalent to \fIregexp:split/2\fR\& with the exception that \fIN\fR\& defines the maximum number of fields in \fIFieldList\fR\&\&.
.RE

.LP
.B
split_script_path(RequestLine) -> Splitted
.br
.RS
.LP
Types:

.RS 3
RequestLine = string()
.br
Splitted = not_a_script | {Path, PathInfo, QueryString}
.br
Path = QueryString = PathInfo = string()
.br
.RE
.RE
.RS
.LP
\fIsplit_script_path/1\fR\& is equivalent to \fIsplit_path/1\fR\& with one exception\&. If the longest possible path is not a regular, accessible, and executable file, then \fInot_a_script\fR\& is returned\&.
.RE

.LP
.B
split_path(RequestLine) -> {Path,QueryStringOrPathInfo}
.br
.RS
.LP
Types:

.RS 3
RequestLine = Path = QueryStringOrPathInfo = string()
.br
.RE
.RE
.RS
.LP
\fIsplit_path/1\fR\& splits \fIRequestLine\fR\& in a file reference (\fIPath\fR\&), and a \fIQueryString\fR\& or a \fIPathInfo\fR\& string as specified in RFC 2616\&. A \fIQueryString\fR\& is isolated from \fIPath\fR\& with a question mark (\fI?\fR\&) and \fIPathInfo\fR\& with a slash (/)\&. In the case of a \fIQueryString\fR\&, everything before \fI?\fR\& is a \fIPath\fR\& and everything after \fI?\fR\& is a \fIQueryString\fR\&\&. In the case of a \fIPathInfo\fR\&, \fIRequestLine\fR\& is scanned from left-to-right on the hunt for longest possible \fIPath\fR\& being a file or a directory\&. Everything after the longest possible \fIPath\fR\&, isolated with a \fI/\fR\&, is regarded as \fIPathInfo\fR\&\&. The resulting \fIPath\fR\& is decoded using \fIdecode_hex/1\fR\& before delivery\&.
.RE

.LP
.B
strip(String) -> Stripped
.br
.RS
.LP
Types:

.RS 3
String = Stripped = string()
.br
.RE
.RE
.RS
.LP
\fIstrip/1\fR\& removes any leading or trailing linear white space from the string\&. Linear white space is to be read as horizontal tab or space\&.
.RE

.LP
.B
suffix(FileName) -> Suffix
.br
.RS
.LP
Types:

.RS 3
FileName = Suffix = string()
.br
.RE
.RE
.RS
.LP
\fIsuffix/1\fR\& is equivalent to \fIfilename:extension/1\fR\& with the exception that \fISuffix\fR\& is returned without a leading dot (\fI\&.\fR\&)\&.
.RE

.SH "SEE ALSO"

.LP
httpd(3erl)