NAME

Jifty::Request - Canonical internal representation of an incoming Jifty request

DESCRIPTION

This document discusses the ins and outs of getting data from the web browser (or any other source) and figuring out what it means. Most of the time, you won't need to worry about the details, but they are provided below if you're curious.

This class parses the submission and makes it available as a protocol-independent Jifty::Request object.

Each request contains several types of information:

actions: A request may contain one or more actions; these are represented as Jifty::Request::Action objects. Each action request has a moniker, a set of submitted arguments, and an implementation class. By default, all actions that are submitted are run; it is possible to only mark a subset of the submitted actions as "active", and only the active actions will be run. These will eventually become full-fledged Jifty::Action objects.
state variables: State variables are used to pass around bits of information which are needed more than once but not often enough to be stored in the session. Additionally, they are per-browser window, unlike session information.
continuations: Continuations can be called or created during the course of a request, though each request has at most one "current" continuation. See Jifty::Continuation.
(optional) fragments: Fragments are standalone bits of reusable code. They are most commonly used in the context of AJAX, where fragments are the building blocks that can be updated independently. A request is either for a full page, or for multiple independent fragments. See Jifty::Web::PageRegion.

METHODS

BUILD PARAMHASH

Creates a new request object. For each key in the "PARAMHASH", the method of that name is called, with the "PARAMHASH"'s value as its sole argument.

setup_subrequest_env

Copies the bare minimals of the plack environment from the top request; this is called in "BUILD" if the request is a subrequest.

clone

Return a copy of the request.

promote

Attempt to fill in the request from any number of various methods -- YAML, JSON, etc. Falls back to query parameters. Takes a Plack::Request object.

from_data_structure

Fills in the request from a data structure. This is called once the YAML or JSON has been parsed. See "SERIALIZATION" for details of how to construct a proper data structure.

Returns itself.

from_args REQ

Calls "from_webform" with the "parameters" in Plack::Request after splitting "|"'s in argument names. See "argument munging".

Returns itself.

from_webform %QUERY_ARGS

Parses web form arguments into the Jifty::Request data structure. Takes in the query arguments. See "SERIALIZATION" for details of how query parameters are parsed.

Returns itself.

argument KEY [=> VALUE]

Merges a single query parameter into the request. This may add actions, change action arguments, or change state variables.

template_argument KEY [=> VALUE]

Sets an argument for the current template. Template arguments, unlike values set via "argument", cannot add actions, change action argument, or change state variables. They are also not stored in continuations.

delete KEY

Removes the argument supplied -- this is the opposite of "argument", above.

parse_form_field_name FIELDNAME

Takes a form field name generated by a Jifty action. Returns a tuple of

type: A slightly-too-opaque identifier
moniker: The moniker for this field's action.
argument name: The argument name.

webform_to_data_structure HASHREF

Converts the data from a webform's %args to the data structure that Jifty::Request uses internally.

XXX TODO: ALEX: DOC ME

continuation_id [CONTINUATION_ID]

Gets or sets the ID of the current continuation associated with the request.

continuation [CONTINUATION]

Returns the current Jifty::Continuation object associated with this request, if any.

future_continuation_id

Gets or sets the ID of the continuation that we are about to return or call into.

future_continuation

Returns the Jifty::Continuation that we are about to return or call into, if any.

save_continuation

Saves the current request and response if we've been asked to. If we save the continuation, we redirect to the next page -- the call to "save_continuation" never returns.

call_continuation

Calls the Jifty::Continuation associated with this request, if there is one. Returns true if the continuation was called successfully -- if calling the continuation requires a redirect, this function will throw an exception to its enclosing dispatcher.

return_from_continuation

Returns from the current continuation, if there is one. If the request path doesn't match, we call the continuation again, which should redirect to the right place. If we have to do this, we return true, which should be taken as a sign to not process the request further.

path

Returns the path that was requested

just_validating

This method returns true if the request was merely for validation. If this flag is set, then all active actions are validated, but no actions are run.

state_variables

Returns an array of all of this request's state variables, as Jifty::Request::StateVariables.

state_variable NAME

Returns the Jifty::Request::StateVariable object for the variable named NAME, or undef of there is no such variable.

add_state_variable PARAMHASH

Adds a state variable to this request's internal representation. Takes a "key" and a "value"; returns the newly-added Jifty::Request::StateVariable.

remove_state_variable KEY

Removes the given state variable. The opposite of "add_state_variable", above.

clear_state_variables

Remove all the state variables.

actions

Returns a list of the actions in the request, as Jifty::Request::Action objects.

action MONIKER

Returns a Jifty::Request::Action object for the action with the given moniker, or undef if no such action was sent.

add_action PARAMHASH

Required argument: "moniker".

Optional arguments: "class", "order", "active", "arguments".

Adds a Jifty::Request::Action with the given moniker to the request. If the request already contains an action with that moniker, it merges it in, overriding the implementation class, active state, and individual arguments. Returns the newly added Jifty::Request::Action.

See Jifty::Action.

clear_actions

Removes all actions from this request

remove_action MONIKER

Removes an action with the given moniker.

fragments

Returns a list of fragments requested, as Jifty::Request::Fragment objects.

fragment NAME

Returns the requested fragment with that name

add_fragment PARAMHASH

Required arguments: "name", "path"

Optional arguments: "arguments", "wrapper"

Adds a Jifty::Request::Fragment with the given name to the request. If the request already contains a fragment with that name, it merges it in. Returns the newly added Jifty::Request::Fragment.

See Jifty::PageRegion.

do_mapping PARAMHASH

Takes two possible arguments, "request" and "response"; they default to the current Jifty::Request and the current Jifty::Response. Calls "map" in Jifty::Request::Mapper on every argument of this request, pulling arguments and results from the given "request" and "response".

is_subrequest

Returns true if this request is a subrequest.

top_request

Returns the top-level request for this request; if this is a subrequest, this is the user-created request that the handler got originally. Otherwise, returns itself;

Jifty::Request::Action

A small package that encapsulates the bits of an action request:

moniker [NAME]

argument NAME [VALUE]

arguments

class [CLASS]

order [INTEGER]

active [BOOLEAN]

has_run [BOOLEAN]

delete

Jifty::Request::StateVariable

A small package that encapsulates the bits of a state variable:

key

value

Jifty::Request::Fragment

A small package that encapsulates the bits of a fragment request:

name [NAME]

path [PATH]

wrapper [BOOLEAN]

in_form [BOOLEAN]

argument NAME [VALUE]

arguments

delete

SERIALIZATION

CGI Query parameters

The primary source of Jifty requests through the website are CGI query parameters. These are requests submitted using CGI GET or POST requests to your Jifty application.

argument munging

In addition to standard Mason argument munging, Jifty also takes arguments with a name of

   bla=bap|beep=bop|foo=bar

and an arbitrary value, and makes them appear as if they were actually separate arguments. The purpose is to allow submit buttons to act as if they'd sent multiple values, without using JavaScript.

actions

registration

For each action, the client sends a query argument whose name is "J:A-moniker" and whose value is the fully qualified class name of the action's implementation class. This is the action "registration." The registration may also take the form "J:A-order-moniker", which also sets the action's run order.

arguments

The action's arguments are specified with query arguments of the form "J:A:F-argumentname-moniker". To cope with checkboxes and the like (which don't submit anything when left unchecked) we provide a level of fallback, which is checked if the first doesn't exist: "J:A:F:F-argumentname-moniker".

state variables

State variables are set via "J:V-name" being set to the value of the state parameter.

continuations

The current continuation set by passing the parameter "J:C", which is set to the id of the continuation. To create a new continuation, the parameter "J:CREATE" is passed. Calling a continuation is a simple as passing "J:CALL" with the id of the continuation to call; this will redirect to the appropriate url, with <J:RETURN> set.

request options

The existence of "J:VALIDATE" says that the request is only validating arguments. "J:ACTIONS" is set to a exclamation mark separated list of monikers; the actions with those monikers will be marked active, while all other actions are marked inactive. In the absence of "J:ACTIONS", all actions are active.