NAME¶
rest - define REST web APIs and call them inline or asychronously
SYNOPSIS¶
package require
Tcl 8.5
package require
rest ?1.0.1?
::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 transformations 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.
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 commands. 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 configuration options below. After creating
the definitions simply call rest::create_interface on the array to create the
commands.
::${name}::basic_auth
u p ::${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 identifiers
- ::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
- 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 configure 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 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 created 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
associated 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 commands 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 following
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 respective
sites.