[plantuml]
....
@startuml
!includeurl https://raw.githubusercontent.com/plantuml-stdlib/C4-PlantUML/v2.0.1/C4_Component.puml

' uncomment the following line to make proposals
'LAYOUT_AS_SKETCH()

title System Component diagram for Decidim Applications (https://decidim.org)


ContainerDb(rel_db, "Relational Database", "PostgreSQL 9.5.x", "Stores users, participatory processes, assemblies, initiatives, proposals, meetings, etc.")
Container(filesystem, "File System", "Local or remote", "Stores uploads (images, documents, etc.)")
Container(worker, "Worker", "Ruby on Rails 5.2", "ActiveJob queues for non syncronuos jobs. Works for open data requests, sending emails, etc.")

Container_Boundary(web_app, "Web Application") {

    Component(admin, "Admin module", "Ruby On Rails Engine", "Internal. Admin panel, mounted in /admin")
    Component(api, "API module", "Ruby On Rails Engine", "Internal. GraphQL API, mounted in /api")
    Component(core, "Core module", "Ruby On Rails Engine", "Internal. Provides APIs as building blocks to be consumed by the rest of the modules.")
    Component(comments, "Comments module", "Ruby On Rails Engine", "Provides the Commentable capability to other modules.")
    Component(dev, "Dev module", "Ruby On Rails Engine", "Aids the local development of Decidim's components.")
    Component(forms, "Forms module", "Ruby On Rails Engine", "Provides APIs for working with forms to other modules (like Surveys and Meetings)")
    Component(generators, "Generator module", "Ruby On Rails Engine", "Provides the decidim Command Line Interface.")
    Component(system, "System module", "Ruby On Rails Engine", "Multitenant configuration, mounted in /system. Can create and manage all the instances of an installation.")
    Component(verifications, "Verifications module", "Ruby On Rails Engine", " Offers several methods for allowing participants to get authorization to perform certain privileged actions.")

    Component(assemblies, "Assemblies module", "Ruby On Rails Engine (Space)", "A permament Space, mounted in /assemblies.")
    Component(conferences, "Conferences module", "Ruby On Rails Engine (Space)", "A temporal Space, mounted in /conferences.")
    Component(initiatives, "Initiatives module", "Ruby On Rails Engine (Space)", "A bottom-up Space, mounted in /initiatives. A participant can collect signatures to bring an issue to the organization.")
    Component(participatory_processes, "Participatory Processes module (Space)", "Ruby On Rails Engine", "A temporal Space, mounted in /processes.")

    Component(accountability, "Accountability module", "Ruby On Rails Engine", "Component. Adds an accountability section to any participatory space so users can follow along the state of the accepted proposals.")
    Component(budgets, "Budgets module", "Ruby On Rails Engine", "Component. Adds a participatory budgets system to any participatory space.")
    Component(blogs, "Blogs module", "Ruby On Rails Engine", "Component. Makes possible to add posts ordered by publication time to spaces.")
    Component(debates, "Debates module", "Ruby On Rails Engine", "Component. Adds a CRUD engine to the admin and public view scoped inside the participatory process.")
    Component(elections, "Elections module", "Ruby On Rails Engine", "Components. Adds voting with cryptographic capabilities.")
    Component(meetings, "Meetings module", "Ruby On Rails Engine", "Component. Adds a CRUD engine to the admin and public view scoped inside the participatory process.")
    Component(pages, "Pages module", "Ruby On Rails Engine", "Component. adds static page capabilities to any participatory space. It basically provides an interface to include arbitrary HTML content to any step.")
    Component(proposals, "Proposals module", "Ruby On Rails Engine", "Component. Adds one of the main components of Decidim: allows users to contribute to a participatory space by creating proposals.")
    Component(surveys, "Surveys module", "Ruby On Rails Engine", "Component. Makes possible to publish surveys (for registered participants or visitors users).")
    Component(sortitions, "Sortitions module", "Ruby On Rails Engine", "Component. makes possible to select randomly a number of proposals among a set of proposals (or a category of proposals within a set) maximizing guarantees of randomness and avoiding manipulation of results by the administrator.")

    Rel(surveys, forms, "Consumes")
    Rel(meetings, forms, "Consumes")
    Rel_Back(forms, elections, "Consumes")

    ' Rel(proposals, assemblies, "Mounts in")
    ' Rel(proposals, participatory_processes, "Mounts in")
    ' Rel(proposals, conferences, "Mounts in")
'
    ' Rel(initiatives, comments, "Consumes")
    ' Rel(accountability, comments, "Consumes")
    ' Rel(budgets, comments, "Consumes")
    ' Rel(sortitions, comments, "Consumes")
    ' Rel(dev, comments, "Consumes")
    ' Rel(meetings, comments, "Consumes")
    ' Rel(debates, comments, "Consumes")
    ' Rel(proposals, comments, "Consumes")
    ' Rel(blogs, comments, "Consumes")
'
    ' Rel(initiatives, admin, "Managed in")
    ' Rel(accountability, admin, "Managed in")
    ' Rel(budgets, admin, "Managed in")
    ' Rel(sortitions, admin, "Managed in")
    ' Rel(meetings, admin, "Managed in")
    ' Rel(debates, admin, "Managed in")
    ' Rel(proposals, admin, "Managed in")
    ' Rel(blogs, admin, "Managed in")
    ' Rel(elections, admin, "Managed in")

}

System_Ext(decidim_bulletin_board_system, "Decidim Bulletin Board", "Allows participants to cast end-to-end verifiable secret votes.")
System_Ext(mail_system, "SMTP system (e-mail)", "Sends mails to users, like confirmations, reminders, notifications, etc.")
System_Ext(etherpad_system, "Etherpad-Lite system", "Optional. Allows real-time text edition in Meetings.")
System_Ext(geocoding_system, "Geocoding system", "Optional. An Open Street Maps provider, allows geographical localization of Proposals and Meetings..")
System_Ext(oauth_system, "OAUTH2 System", "Optional. Third party sign on systems. Could be Twitter, Facebook, Google or any other OAUTH2 providers.")

Rel_Back_Neighbor(decidim_bulletin_board_system, elections, "Uses")
Rel_Neighbor(worker, mail_system, "Sends e-mails", "SMTP")
Rel(web_app, rel_db, "Uses")
Rel(web_app, filesystem, "Uses")
Rel(web_app, oauth_system, "Uses")
Rel(web_app, geocoding_system, "Uses")
Rel(web_app, etherpad_system, "Embeds", "Through an Iframe")
@enduml
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