Provided by: erlang-manpages_20.2.2+dfsg-1ubuntu2_all 
NAME
httpd_util - Miscellaneous utility functions to be used when implementing
Erlang web server API modules.
DESCRIPTION
This module provides the Erlang web server API module programmer with miscellaneous utility functions.
EXPORTS
convert_request_date(DateString) -> ErlDate|bad_date
Types:
DateString = string()
ErlDate = {{Year,Month,Date},{Hour,Min,Sec}}
Year = Month = Date = Hour = Min = Sec = integer()
convert_request_date/1 converts DateString to the Erlang date format. DateString must be in one of
the three date formats defined in RFC 2616.
create_etag(FileInfo) -> Etag
Types:
FileInfo = file_info()
Etag = string()
create_etag/1 calculates the Etag for a file from its size and time for last modification.
FileInfo is a record defined in kernel/include/file.hrl.
day(NthDayOfWeek) -> DayOfWeek
Types:
NthDayOfWeek = 1-7
DayOfWeek = string()
day/1 converts the day of the week (NthDayOfWeek) from an integer (1-7) to an abbreviated string,
that is:
1 = "Mon", 2 = "Tue", ..., 7 = "Sat".
decode_hex(HexValue) -> DecValue
Types:
HexValue = DecValue = string()
Converts the hexadecimal value HexValue into its decimal equivalent (DecValue).
flatlength(NestedList) -> Size
Types:
NestedList = list()
Size = integer()
flatlength/1 computes the size of the possibly nested list NestedList, which can contain binaries.
hexlist_to_integer(HexString) -> Number
Types:
Number = integer()
HexString = string()
hexlist_to_integer converts the hexadecimal value of HexString to an integer.
integer_to_hexlist(Number) -> HexString
Types:
Number = integer()
HexString = string()
integer_to_hexlist/1 returns a string representing Number in a hexadecimal form.
lookup(ETSTable,Key) -> Result
lookup(ETSTable,Key,Undefined) -> Result
Types:
ETSTable = ets_table()
Key = term()
Result = term() | undefined | Undefined
Undefined = term()
lookup extracts {Key,Value} tuples from ETSTable and returns the Value associated with Key. If
ETSTable is of type bag, only the first Value associated with Key is returned. lookup/2 returns
undefined and lookup/3 returns Undefined if no Value is found.
lookup_mime(ConfigDB,Suffix)
lookup_mime(ConfigDB,Suffix,Undefined) -> MimeType
Types:
ConfigDB = ets_table()
Suffix = string()
MimeType = string() | undefined | Undefined
Undefined = term()
lookup_mime returns the MIME type associated with a specific file suffix as specified in the file
mime.types (located in the config directory).
lookup_mime_default(ConfigDB,Suffix)
lookup_mime_default(ConfigDB,Suffix,Undefined) -> MimeType
Types:
ConfigDB = ets_table()
Suffix = string()
MimeType = string() | undefined | Undefined
Undefined = term()
lookup_mime_default returns the MIME type associated with a specific file suffix as specified in
the mime.types file (located in the config directory). If no appropriate association is found,
the value of DefaultType is returned.
message(StatusCode,PhraseArgs,ConfigDB) -> Message
Types:
StatusCode = 301 | 400 | 403 | 404 | 500 | 501 | 504
PhraseArgs = term()
ConfigDB = ets_table
Message = string()
message/3 returns an informative HTTP 1.1 status string in HTML. Each StatusCode requires a
specific PhraseArgs:
301:
string(): A URL pointing at the new document position.
400 | 401 | 500:
none (no PhraseArgs).
403 | 404:
string(): A Request-URI as described in RFC 2616.
501:
{Method,RequestURI,HTTPVersion}: The HTTP Method, Request-URI, and HTTP-Version as defined in
RFC 2616.
504:
string(): A string describing why the service was unavailable.
month(NthMonth) -> Month
Types:
NthMonth = 1-12
Month = string()
month/1 converts the month NthMonth as an integer (1-12) to an abbreviated string, that is:
1 = "Jan", 2 = "Feb", ..., 12 = "Dec".
multi_lookup(ETSTable,Key) -> Result
Types:
ETSTable = ets_table()
Key = term()
Result = [term()]
multi_lookup extracts all {Key,Value} tuples from an ETSTable and returns all Values associated
with Key in a list.
reason_phrase(StatusCode) -> Description
Types:
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
Description = string()
reason_phrase returns Description of an HTTP 1.1 StatusCode, for example, 200 is "OK" and 201 is
"Created". For more information, see RFC 2616.
rfc1123_date() -> RFC1123Date
rfc1123_date({{YYYY,MM,DD},{Hour,Min,Sec}}) -> RFC1123Date
Types:
YYYY = MM = DD = Hour = Min = Sec = integer()
RFC1123Date = string()
rfc1123_date/0 returns the current date in RFC 1123 format. rfc_date/1 converts the date in the
Erlang format to the RFC 1123 date format.
split(String,RegExp,N) -> SplitRes
Types:
String = RegExp = string()
SplitRes = {ok, FieldList} | {error, errordesc()}
Fieldlist = [string()]
N = integer
split/3 splits String in N chunks using RegExp. split/3 is equivalent to regexp:split/2 with the
exception that N defines the maximum number of fields in FieldList.
split_script_path(RequestLine) -> Splitted
Types:
RequestLine = string()
Splitted = not_a_script | {Path, PathInfo, QueryString}
Path = QueryString = PathInfo = string()
split_script_path/1 is equivalent to split_path/1 with one exception. If the longest possible path
is not a regular, accessible, and executable file, then not_a_script is returned.
split_path(RequestLine) -> {Path,QueryStringOrPathInfo}
Types:
RequestLine = Path = QueryStringOrPathInfo = string()
split_path/1 splits RequestLine in a file reference (Path), and a QueryString or a PathInfo string
as specified in RFC 2616. A QueryString is isolated from Path with a question mark (?) and
PathInfo with a slash (/). In the case of a QueryString, everything before ? is a Path and
everything after ? is a QueryString. In the case of a PathInfo, RequestLine is scanned from left-
to-right on the hunt for longest possible Path being a file or a directory. Everything after the
longest possible Path, isolated with a /, is regarded as PathInfo. The resulting Path is decoded
using decode_hex/1 before delivery.
strip(String) -> Stripped
Types:
String = Stripped = string()
strip/1 removes any leading or trailing linear white space from the string. Linear white space is
to be read as horizontal tab or space.
suffix(FileName) -> Suffix
Types:
FileName = Suffix = string()
suffix/1 is equivalent to filename:extension/1 with the exception that Suffix is returned without
a leading dot (.).
SEE ALSO
httpd(3erl)