Submissions Library

Project goal

Make activity module developers (not only Assignment developers) able to use submission types: both standard and community-developed.

Project scope

A library providing API for activity module submission types support implementation. Actual proposition is to make assignsubmission plugins system-level.

The existing modules requiring submissions (Assignment, Workshop) should use this library.

Relevant tracker issues

1. MDL-47344 - Allow usage of submission methods in other plugins

Use cases

1. Assignment: no comment.
2. Workshop: uses submissions but it's another code doing the same.
3. Community module: for example, Assignment with individual tasks could not re-implement all existing submission types.
4. Non-module usage? Essay or similar manually graded question types could use assignments plugins to imporve their functionality, scope and standartisation.

Database schema

submissions_bindings

Identifies all connected submission plugins to an activity modules.

Field	Type	Default	Description
id	bigint		Auto-numbered.
context	bigint		Activity context.
area	varchar(100)		An area within activity module. A module may have a few.
method	varchar(100)		Submission plugin name. It is considered that the plugin is activated in these area of these activity module instance.

submissions_pluginconfig

Stores plugins configuration.

Field	Type	Default	Description
id	bigint		Auto-numbered.
binding	bigint		Activated plugin. Points to submissions_bindings record.
option	varchar(100)		Plugin setting name.
value	text		Setting value.

submissions_instances

Identifies all submissions. A data associated with the submission is stored by plugin.

Field	Type	Default	Description
id	bigint		Auto-numbered.
binding	bigint		Activated plugin. Points to submissions_bindings record.
itemid	bigint	null	Identifies an element within area. For example, answer or user id.
timecreated	bigint	0	When the submission was created.
timemodified	bigint	0	Latest submission modification time.
status	int	0	Draft (default), Latest, Archived.

submissionplugin_onlinetext

This is a table example for "Online text" plugin. This table is not a part of library.

Field	Type	Default	Description
id	bigint		Auto-numbered.
submissioninstance	bigint		Point to submission from submissions_instances table.
onlinetext	text		Actual submission data.
onlineformat	int	0	Text format.

submissionplugin_file

This is a table example for "File submission" plugin. This table is not a part of library.

Field	Type	Default	Description
id	bigint		Auto-numbered.
submissioninstance	bigint		Point to submission from submissions_instances table.
numfiles	bigint		Number of submitted files.

How it works

API for activity modules

Activity instance settings form

In order to add a plugin settings elements on activity settings page the following method of moodleform_mod should be used:

$this->standard_submission_coursemodule_elements();

Displaying a submission

Activity module should access the submissions using a submission class.

$submission = new submission($context, $area);

First, a submission_instance object should be retrieved.

$submissioninstance = $submission->get_submission_instance($itemid);

Next, it can be displayed.

if ($submissioninstance) {
    $submissioninstance->display();
    // or
    $html = $submissioninstance->render();
}

Displaying submission form

Activity module should access the submissions using a submission class.

$submission = new submission($context, $area);

A special method should be used to add elements on submission form. A previous submission can be loaded by specifying $baseitemid.

$submission->add_submission_form_elements($mform, $baseitemid);

Save/update submission

Activity module should access the submissions using a submission class.

$submission = new submission($context, $area);

To save or update the submission a special method should be used. It accepts submitted form data as its only argument.

$submission->save($formdata);

Delete submission

All submissions associated with the activity module instance can be deleted by using the following static method:

submission::delete_all_for_context($context);

Individual submissions can be deleted this way:

$submission = new submission($context, $area);
$submission->delete($itemid);

General workflow details

Student makes a submission

UML Sequence Diagram: student makes a submission

TODO: add more details

Teacher views student's submission

UML Sequence Diagram: teacher views student's submission

TODO: add more details

Someone tries to download a file from submissionplugin_file

UML Sequence Diagram: someone tries to download a file

See also: #Accessing files

TODO: add more details

Course module deletion

UML Sequence Diagram: course module deletion

submission::delete_all_for_context(...) call should be added to course_delete_module(...) function.

Note: all associated files will be deleted when course_delete_module(...) function calls deletion of all files associated with the module's context. Perhaps submission plugins should not rely on this.

How "File submission" plugin stores files

File submission plugin stores all files at file areas identified by:

• context — activity context (from submissions_bindings)
• component name — submissionplugin_file
• area type — submissionplugin_file_<area> (<area> from submissions_bindings)
• itemid — submission instance id.

Accessing files

The activity module should be responsible of giving access to files stored by submission plugins, because only activity module can interpret area and itemid correctly.

Submission plugin development

A main plugin class should be calles submissionplugin_<pluginnname> and it should be inherited from abstract class submissionplugin.

TODO: add detailed description on methods plugin must implement.

Backup/restore

The submission must be a part of activity module instances.

See also

• Assign submission plugins
• Advanced grading methods - if we have a multiple grading areas, each of those area may require a submissions.