rest(3tcl) A framework for RESTful web services rest(3tcl)______________________________________________________________________________NAMErest - define REST web APIs and call them inline or asychronously
SYNOPSIS
package require Tcl 8.5
package require rest ?1.0?
::rest::simple url query ?config? ?body?
::rest::get url query ?config? ?body?
::rest::post url query ?config? ?body?
::rest::head url query ?config? ?body?
::rest::put url query ?config? ?body?
::rest::delete url query ?config? ?body?
::rest::save name file
::rest::describe name
::rest::parameters url ?args?
::rest::parse_opts static required optional string
::rest::substitute string ?var?
::rest::create_interface name
describe
uplevel token token
upvar body body
uplevel token token
uplevel token token
_________________________________________________________________DESCRIPTION
There are 2 types of usage this package supports: simple calls, and
complete interfaces. In an interface you specify a set of rules and
then the package builds commands which correspond to the REST methods.
These commands can have many options such as input and output transfor‐
mations and data type specific formatting. This results in a cleaner
and simpler script. On the other hand, a simple call is easier and
quicker to implement but less featureful. It takes the url and a few
options on the command and returns the result directly. Any formatting
or checking is up to rest of the script. Simple usage In simple usage
you make calls using http method procedures and then check or process
the returned data yourself
::rest::simple url query ?config? ?body?
::rest::get url query ?config? ?body?
::rest::post url query ?config? ?body?
::rest::head url query ?config? ?body?
::rest::put url query ?config? ?body?
::rest::delete url query ?config? ?body?
The above commands are all equivalent except for the http method used.
If you use simple then the method should be specified as an option in
the ?config? dict, otherwise it defaults to get. If a body is needed
then the config dict must be present, however it may be empty.
set appid APPID
set search tcl
set res [rest::get http://boss.yahooapis.com/ysearch/web/v1/$search [list appid $appid]]
set res [rest::format_json $res]
set res [rest::simple http://twitter.com/statuses/update.json [list status $text] {
method post
auth {basic user password}
format json
}
]
the options supported in the config dict are as follows headers cookie
auth format method content-type Interface usage An interface to a REST
API consists of a series of definitions of REST calls contained in an
array. The array name becomes a namespace containing the defined com‐
mands. Each array element defines the name of the call and takes the
form of a dict, aka key/value pairs. These keys are the defined config‐
uration options below. After creating the definitions simply call
rest::create_interface on the array to create the commands.
package require rest
set yweather(forecast) {
url http://weather.yahooapis.com/forecastrss
req_args { p: }
opt_args { u: }
}
rest::create_interface yweather
puts [yweather::forecast -p 94089]
::${name}::basic_auth u p ::${name}::set_static_args ?args?]
::rest::save name file
saves a copy of the dynamically created procs to a file for
later loading
::rest::describe name
print a description of defined api calls
::rest::parameters url ?args?
parse a url query string into a dict
::rest::parse_opts static required optional string
::rest::substitute string ?var?
take a string and substitute real values for any option identi‐
fiers
::rest::create_interface name
TOKENS the value is substituted into the url at call time.
tokens in the form of %name:default_value% will be an optional
argument with a default value. url the target of the http
request description a string which describes the call. used only
for
describe
body indicates if arguments are required for the request body or
not. should be one of none, optional, required, argument or
mime_multipart. default is optional. if argument is used then
the option is parsed as a list where the second value is the
name of a option. the body will then be used as the value for
that option. if the value is mime_multipart then the body is
required and interpreted as each argument representing one part
of a mime multipart document. each argument should be a 2 item
list with the first being a list of header keys and values, and
the second being the mime part body.
set ygeo(parse) {
url http://wherein.yahooapis.com/v1/document
method post
body { arg documentContent }
}
ygeo::parse "san jose ca"
# "san jose ca" will be interpreted as if it were specified as the -documentContent option
set gdocs(upload) {
url http://docs.google.com/feeds/default/private/full
body mime_multipart
}
gdocs::upload [list {Content-Type application/atom+xml} $xml] [list {Content-Type image/jpeg} $filedata]
method The HTTP method to call on the url. The default is GET.
copy this copies the definition of a previously defined call.
after copying you can override selected options by defining them
again. unset removes the named option. useful when using copy
of another definition. headers the value must be another dict
containing header fields and their values. The default is to not
add any additional headers. content-type Specifies the content
type for the request data. req_args a list of the required
arguments. names ending in a colon will require a value.
opt_args arguments that may be present but are not required.
static_args arguments that are always the same. no sense in
troubling the user with these. A leading - is allowed but not
required to maintain consistancy with the command line. auth
should be one of basic or sign. if basic is used you can config‐
ure basic auth with the proc auth_basic which takes 2 arguments,
the username and password. if sign is specified then the value
must be a list with the second element being the name of a proc
which will be called to perform the request signing.
set delicious(updated) {
url https://api.del.icio.us/v1/posts/update
auth basic
}
rest::create_interface flickr
flickr::basic_auth username password
set flickr(auth.getToken) {
url http://api.flickr.com/services/rest/
req_args { api_key: secret: }
auth { sign do_signature }
}
rest::create_interface flickr
proc ::flickr::do_signature {query} {
# perform some operations on the query here
return $query
}
callback If this option is present then the method will be cre‐
ated as an async call. An async call will return immediately
with the value of the http token. The event loop must be active
to use this option. The value of this option is the name of a
proc which is invoked when the HTTP call is complete. The proc
receives three arguments, the name of the calling procedure, the
status of the result (one of OK or ERROR), and the data associ‐
ated with the result. the http request header is available via
uplevel token token
cookie a list of cookies to be passed in the http header. this
is just a shortcut to the headers option input_transform com‐
mands which take the variable $query and transform it in some
manner before returning a new value. return value must be a dict
which will be passed to http::formatQuery the request body is
accessible via
upvar body body
format or result defines the format of the returned data. should
be one of discard, raw, json, xml, or tdom. the default is auto
which should auto detect between xml and json. rss is formated
as a special case of xml. pre_transform this value takes the
form of a proc which should perform some action on $result and
return a value. it is run on the result before the output
(xml/json/etc) transformation is done. the http request header
is available via
uplevel token token
result may have the value xml, json, tdom, raw, or auto. the
default is auto and should auto detect json or xml results and
transform them into a tcl list. this is here if you want to
specify it explicitly. post_transform this value takes the form
of a proc which should perform some action on $result and return
a value. it is run on the result after the output transformation
but before returning the value to the calling procedure. the
http request header is available via
uplevel token token
check_result this value should be a list of 2 expressions either
of which may be empty. the first expression is checks the OK
condition, it must return true when the result is satisfactory.
the second expression is the error condition, it must return
false unless there is an error.
INCLUDED
functional but incomplete implementations are included for the follow‐
ing services: flickr twitter yahoo boss yahoo weather google calendar
facebook del.icio.us read the file or source it and use describe for
more information. also see the developers documentation on the respec‐
tive sites.
rest 1.0 rest(3tcl)
