ActionController::Base

Serves this controller and its descendants, passing route misses downstream.

the action name being executed (typically the function name)

attempts to find the clients IP address using proxy headers or the remote_address

the request context

parses the cookies sent with the request

returns any file provided in a multipart post

returns any data that could be parsed from the request body.

It will only attempt to parse the data if the appropriate content-type header is set

the MCP request this route is running for, nil for regular HTTP requests. See ActionController::MCPServer::RequestContext

parses all the params (query + route + body form data) and makes them available in one place

parses the query params that were sent with the request

parses the query params that were sent with the request

has the response already been sent?

has the response already been sent?

shortcuts to methods available on the context

shortcuts to methods available on the context

looks at the content type header to see if the charset was defined

looks at the content type header for the media type and returns the text representation of it

looks at the content type header for the media type

returns either :http or :https

shortcuts to methods available on the context

shortcuts to methods available on the context

shortcuts to methods available on the context

shortcuts to methods available on the context

Builds a URL with this request's mounted base and bound path parameters.

loads the session from the cookies if it exists

Sets the etag and/or last_modified on the response and checks it against the client request. If it’s fresh and we don’t need to generate anything, a reply of 304 Not Modified is sent.

runs code after an action is executed and the response has been sent.

@[AC::Route::Filter(:after_action)]
def audit_user_activity
  log_activity(session["user"], request_protocol, action_name)
end

wraps actions in the code provided, must yield to the action

@[AC::Route::Filter(:around_action, only: [:create, :update])]
def wrap_in_transaction(&)
  PgORM::Database.transaction do
    yield
  end
end

NOTE: unlike before_action and after_action, which compile to ordinary method calls, an around filter has to yield and so Crystal inlines its body into every route it applies to. A filter carrying a lot of code is duplicated once per route; keep the body thin and put the work in a regular method:

@[AC::Route::Filter(:around_action)]
def instrument(&)
  started = start_metrics
  yield
ensure
  record_metrics(started)
end

this route is appended to any routes defined in the controller

defaults to /

runs code before an action is executed

@[AC::Route::Filter(:before_action, except: [:public_show])]
def ensure_authenticated
  raise Error::Unauthorized.new("user not found") unless session["user"]?
end

define a new route that responds to DELETE requests

internal: true routes are not exposed via HTTP, they're used to implement MCP prompts

bind every route in this controller to a named response execution context.

The context must be declared with ActionController::ExecutionContext.define. A per-route execution_context: annotation takes precedence over this. Has no effect unless execution contexts are enabled (ExecutionContext::ENABLED).

class Reports < ActionController::Base
  execution_context "reports"
end

ensures routes can only be accessed over TLS, plain HTTP requests are redirected to HTTPS (websockets are refused). Applies to every route when neither only: nor except: is provided.

the protocol is determined by ActionController::Support.request_protocol: proxy headers, otherwise whether the connection is to a port Server bound with TLS.

recommended that this is enabled for your entire application

ensures routes can only be accessed over TLS, plain HTTP requests are redirected to HTTPS (websockets are refused). Applies to every route when neither only: nor except: is provided.

the protocol is determined by ActionController::Support.request_protocol: proxy headers, otherwise whether the connection is to a port Server bound with TLS.

recommended that this is enabled for your entire application

define a new route that responds to GET requests

internal: true routes are not exposed via HTTP, they're used to implement MCP prompts

Mount a controller subtree with a replacement base relative to this controller.

define a new route that responds to OPTIONS requests

internal: true routes are not exposed via HTTP, they're used to implement MCP prompts

define a new route that responds to PATCH requests

internal: true routes are not exposed via HTTP, they're used to implement MCP prompts

define a new route that responds to POST requests

internal: true routes are not exposed via HTTP, they're used to implement MCP prompts

define a new route that responds to PUT requests

internal: true routes are not exposed via HTTP, they're used to implement MCP prompts

provide custom responses for certain types of errors that might occur in multiple routes

helps keep your code DRY and simplifies controller methods

provides a method for skipping filters that were defined in parent classes.

for instance, you might have a global authorisation check, however one route is less strict

skip_action :authorize!, only: [:public_show]

used to define a websocket route