HTTP Handlers

Detailed Description

Handlers are components that could be used by components::Server to process the incoming requests.

All the HTTP handlers derive from server::handlers::HttpHandlerBase and override its methods to provide functionality.

See Userver Components for more information on how to register components.

Configuration

All the handlers inherit configuration options from their base classes:

• server::handlers::HandlerBase
• server::handlers::HttpHandlerBase

All the components, including handlers, also have the load-enabled option.

Static configuration example:

Here's an example of the full config for the server::handlers::Ping handle.

# yaml
    handler-ping:
        # Options from server::handlers::HandlerBase
        path: /ping
        method: GET
        task_processor: main-task-processor
        max_request_size: 256
        max_headers_size: 256
        parse_args_from_body: false
        # auth: TODO:
        url_trailing_slash: strict-match
        max_requests_in_flight: 100
        request_body_size_log_limit: 128
        response_data_size_log_limit: 128
        max_requests_per_second: 100
        decompress_request: false
        throttling_enabled: false
        set-response-server-hostname: false
 
        # Options from server::handlers::HttpHandlerBase
        log-level: WARNING
 
        # Common component options
        load-enabled: true

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⇦ Clients | Http server middlewares ⇨

Collaboration diagram for HTTP Handlers:

Classes
class	alerts::Handler
	Handler that returns the list of active fired alerts. More...
class	server::handlers::DnsClientControl
	Handlers that controls the DNS client. More...
class	server::handlers::DynamicDebugLog
	Handler for forcing specific lines logging. Feature also known as dynamic debug logging. More...
class	server::handlers::HttpHandlerBase
	Base class for all the Userver HTTP Handlers. More...
class	server::handlers::HttpHandlerFlatbufBase< InputType, ReturnType >
	Convenient base for handlers that accept requests with body in Flatbuffer format and respond with body in Flatbuffer format. More...
class	server::handlers::HttpHandlerJsonBase
	Convenient base for handlers that accept requests with body in JSON format and respond with body in JSON format. More...
class	server::handlers::HttpHandlerStatic
	Handler that returns HTTP 200 if file exist and returns file data with mapped content/type. More...
class	server::handlers::ImplicitOptions
	A "magical" handler that will respond to OPTIONS HTTP method for any other handler that cannot handle OPTIONS itself. More...
class	server::handlers::InspectRequests
	Handler that returns information about all in-flight requests. More...
class	server::handlers::Jemalloc
	Handler that controls the jemalloc allocator. More...
class	server::handlers::LogLevel
	Handler that controls logging levels of all the loggers. More...
class	server::handlers::OnLogRotate
	Handler that controls logging levels of all the loggers. More...
class	server::handlers::Ping
	Handler that returns HTTP 200 if the service is OK and able to process requests. More...
class	server::handlers::ServerMonitor
	Handler that returns statistics data. More...
class	server::handlers::TestsControl
	Handler that allows to control the behavior of server from tests, and functional tests with testsuite in particular. More...
class	server::websocket::WebsocketHandlerBase
	Base class for WebSocket handler. More...