trusty (3) Jifty::Manual::Glossary.3pm.gz

NAME

       Jifty::Manual::Glossary - The Jifty dictionary

GLOSSARY

       We use words.  This is what they mean.

       action
           An action is a specifically designed RPC call that can do something to the system, with any number of
           declared "parameter"s.  At runtime, an action can take "argument"s, which it "canonicalize"s,
           "validate"s, and then uses to do something useful.  Each action has a "result".  See Jifty::Action
           and Jifty::Manual::Actions.

       active
           For an "action" to run, it needs to be active.  Most of the time, all actions submitted are active,
           but it is possible to specify only a specific action as active; any non-active actions are ignored.
           See Jifty::Request.

       AJAX
           An acronym standing for Asynchronous Javascript And XML.  Though technically incorrect, it is the
           buzzword that describes doing asynchronous requests to the server while the user waits.  This can
           lead to very "dynamic" pages, as the browser does not need to refresh the entire page to update a
           small section of the screen.  In Jifty, the sections of the screen are called "region"s.  See
           Jifty::Web::PageRegion.

       argument
           An argument is a user-supplied input to fill in a "parameter" in an "action".  See Jifty::Action.

       canonicalize
           To turn an "argument" into a more standard form.  For instance, a canonicalizer could translate a
           user-typed date into a date object or a SQL-formatted date string.  See Jifty::Action.

       collection
           A /collection is a class representing all or a subset of the records stored in the database regarding
           a particular "model". See Jifty::Collection.

       constructor
           A property of a "parameter"; the action must have an argument value for this parameter in order to be
           constructed.  This is different from "mandatory", in that the user can leave mandatory fields empty.
           For instance, the "id" of a Jifty::Action::Record::Update is a constructor.  See Jifty::Action.

       continuation
           A concept stolen from Lisp, Scheme, Smalltalk, and Perl 6.  The continuation of any particular piece
           of code is the deferred operations that care about the return value at that point.  In the context of
           Jifty, a continuation is a deferred "request" that may pull "argument"s and the like from the
           "result"s of the current request.  Continuations can be arbitrarily nested, so they are often useful
           to keep track of tangents that the user went on.  See Jifty::Continuation.

       database version
           The database version is the "schema version" last installed or updated in the application's database.
           In general, the database version will always match the schema version. The exception is when Jifty is
           updated to a new schema version, your application updates to a new schema version, or a plugin
           updates to a new schema version. When this happens, you must "update" your database so that the
           database versions and schema versions match before running your application.

       form field
           A widget which the browser renders.  These are generally useful to ask the user for a value for an
           "argument" to an "action".  See Jifty::Web::Form::Field.

       fragment
           A section of HTML (at present, a Mason component) contained in a "region".  Fragments are a kind of
           standalone Mason component which the browser can request individually.  Because of this, they can
           only take strings and scalars as arguments, not references or objects!

       element
           A Mason component used by one or more other pages, which is not a whole page of itself. As opposed to
           fragments "elements" are strictly internal, and never visible to the outside world by themselves.
           Elements typically live under a path beginning with or containing '/_elements'. This, and the whole
           idea of an element is strictly convention, but Jifty contains elements for things like page headers,
           menus, and showing keybindings out of the box to make your life easier.

       mandatory
           A property of a "parameter"; the user must enter a value for the action to validate.  This is the
           simplest level of validation.

       model
           Jifty uses Jifty::DBI to store its data (though might use other storage tools at some later time).
           The model defines the "schema" and provides a package for creating, reading, updating, and deleting
           records stored in the database. The model is generally a subclass of Jifty::Record. Access multiple
           items from a model is performed through a "collection".

       moniker
           Every instance of a Jifty::Action has a moniker.  Monikers serve as identifiers for actions, to
           associate arguments with actions and to access specific actions "by name".  Monikers need not be
           globally unique, but they must be unique within a single request.  Monikers have no semantic meaning.
           See "monikers" in Jifty::Action

           A moniker is an arbitrary-length nonempty string containing no semicolons. It may not begin with a
           digit.

       parameter
           A parameter is a named parameter to an "action".  Jifty generally renders these on the screen as
           "form field"s.  See Jifty::Param and Jifty::Param::Schema.

       region
           An area of the page which JavaScript can replace.  The content in the region is a "fragment".  Think
           of the region as the box and the fragment as the content in the box.  See Jifty::PageRegion.

       request
           A single query which lists "action"s to run, together with a page or list of "fragment"s to return.
           This most often comes from the browser as query parameters, but may come from other sources as a JSON
           or YAML POST request.  The answer to a request is a "response".  See Jifty::Request.

       response
           The answer to a "request", it contains a "result" for every action that ran.  See Jifty::Response.

       result
           The answer to a "action", it contains information about if the action was a success or failure, and
           further detail about why or how.  It can also contain arbitrary "content".  See Jifty::Result.

       return
           After performing a "tangent" a user may perform a "return" to invoke the "continuation" created by
           the original tangent.

       schema
           The schema for a "model" represents the structure of the data stored in an individual item in that
           model's "collection". See Jifty::DBI::Schema.

       schema version
           The schema version is a number in version object used to determine which "database version" your
           application code is expecting to use. There are three places where the schema version is important:

           1.  Jifty application version. The Jifty application stores some details in the database.

           2.  Your database version. Your application keeps a database version recorded in the configuration.
               See Jifty::Config.

           3.  Plugin versions. Each plugin has a version associated with it affecting whatever "/model"s it
               uses.

           If any of these versions differs from their respective "database version"s, then you need to run the
           Jifty::Script::Schema to "upgrade" to the latest schema version.

           Contrast with "database version".

       sticky
           A property of "form field"s.  If a field is "sticky," values that the user entered appear there again
           when the page is rendered again, avoiding making the user type them again.  Most "action"s have form
           fields which are sticky on failure, so the user can update the information and try again.

       tangent
           A tangent is a link or redirect that causes Jifty to save the current state into a "continuation" for
           a later "return". This operation is handy for situations when you want to jump to another page or
           form, but return to this page when the user is done with the "tangent" page. Because of the use of
           continuations, this can be especially handy because a user could go on multiple tangents and
           eventually return to the start.

       upgrade
           Generally, your Jifty application will change over time. Most of these changes will be simple changes
           to behavior or appearance. When changes are made to the "schema" structure of your database, you may
           need to perform an upgrade. An upgrade is the process by which you rename columns, initialize data,
           or otherwise update information that needs to be updated when a change to the database needs to be
           made. See Jifty::Upgrade, Jifty::Manual::Upgrading, and Jifty::Script::Schema.

       validate
           To check that the provided value of an "argument" is a possible value for it to have.  See
           Jifty::Web::Form::Field.