rstudio/shiny

How rstudio/shiny works

Shiny’s browser runtime turns user interactions with bound widgets into client inputs, sends them through the Shiny session to an R server, then dispatches server updates to output bindings for rendering. Initialization discovers bindings and wires the DOM; specialized image handlers add brush/click/hover interaction, while policies regulate input traffic. This map emphasizes sampled TypeScript runtime code. The R reactive engine, server protocol, and several documented integrations are external or represented only by their enclosing runtime modules.

Components 22

Runtime Initialization

Runtime Entry srcts/src/index.ts
Browser Initialization srcts/src/initialize/browser.ts
Shiny Facade srcts/src/shiny/index.ts
DOM Binding srcts/src/shiny/bind.ts
History Support srcts/src/initialize/history.ts

Inputs And Events

Binding Registry srcts/src/bindings/registry.ts
Input Bindings srcts/src/bindings/input/index.ts
Input Policies srcts/src/inputPolicies/index.ts
File Processor srcts/src/file/fileProcessor.ts
Widget Assets inst/www/shared/selectize/js/selectize.js

Session Transport

Input API srcts/src/shiny/initedMethods.ts
Shiny Session srcts/src/shiny/shinyapp.ts
Notifications srcts/src/shiny/notifications.ts
Reconnect Dialog srcts/src/shiny/reconnectDialog.ts

Outputs And Rendering

Output Registry srcts/src/bindings/registry.ts
Output Bindings srcts/src/bindings/output/index.ts
Content Renderer srcts/src/shiny/render.ts

Interactive Features

Image Handlers srcts/src/imageutils/createHandlers.ts
Image Utilities srcts/src/imageutils/index.ts
Timing Controls srcts/src/time/index.ts

Other components

Browser User
R Shiny Server

Connections 25

Browser User → Browser Initialization: opens app
Runtime Entry → Browser Initialization: starts initialization
Browser Initialization → Shiny Facade: initializes runtime
Shiny Facade → Binding Registry: creates registries
Shiny Facade → DOM Binding: binds DOM
DOM Binding → Binding Registry: resolves bindings
Binding Registry → Input Bindings: provides inputs
Binding Registry → Output Bindings: provides outputs
Browser User → Input Bindings: changes widgets
Input Bindings → Input Policies: applies policies
Input Bindings → File Processor: processes files
Input Bindings → Input API: sets values
Input API → Shiny Session: forwards inputs
Image Handlers → Image Utilities: creates interactions
Image Handlers → Timing Controls: throttles events
Image Handlers → Input API: sets image inputs
Shiny Session → R Shiny Server: sends session data
R Shiny Server → Shiny Session: returns updates
Shiny Session → Output Registry: dispatches updates
Output Registry → Output Bindings: selects outputs
Output Bindings → Content Renderer: renders content
Shiny Session → Notifications: dispatches notices
Shiny Session → Reconnect Dialog: handles reconnects
Shiny Facade → History Support: manages history
Input Bindings → Widget Assets: uses widget library

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