fiery (version 0.2.1)

Fire: Generate a New App Object

Description

The Fire generator creates a new 'Fire'-object, which is the the class containing all app logic. The class is based on the R6 oo-system and is thus reference-based with methods and data attached to each object, in contrast to the more well known S3 and S4 systems.

Format

An object of class R6ClassGenerator of length 24.

Fields

host

A string giving a valid IPv4 address owned by the server, or '0.0.0.0' (the default) to listen on all addresses

port

An integer giving the port number the server should listen on (defaults to 80L)

refreshRate

The interval in seconds between run cycles when running a blocking server (defaults to 0.001)

triggerDir

A valid folder where trigger files can be put when running a blocking server (defaults to NULL)

Methods

ignite(block = TRUE, showcase = FALSE, ...)

Begins the server,either blocking the console if block = TRUE or not. If showcase = TRUE a browser window is opened directing at the server address. ... will be redirected to the 'start' handler(s)

start(block = TRUE, showcase = FALSE, ...)

A less dramatic synonym of for ignite

reignite(block = TRUE, showcase = FALSE, ...)

As ignite but additionally triggers the 'resume' event after the 'start' event

resume(block = TRUE, showcase = FALSE, ...)

Another less dramatic synonym, this time for reignite

extinguish()

Stops a running server

stop()

Boring synonym for extinguish

on(event, handler, pos = NULL)

Add a handler function to to an event at the given position in the handler stack. Returns a string uniquely identifying the handler

off(handlerId)

Remove the handler tied to the given id

trigger(event, ...)

Triggers an event passing the additional arguments to the potential handlers

send(message, id)

Sends a websocket message to the client with the given id, or to all connected clients if id is missing

attach(plugin, ...)

Attaches a plugin to the server. A plugin is an R6 object with an onAttach method

header(name, value)

Add a global header to the server that will be set on all responses

set_data(name, value)

Adds data to the servers internal data store

get_data(name)

Extracts data from the internal data store

remove_data(name)

Removes the data with the given name from the internal data store

time(expr, then, after, loop = FALSE)

Add a timed evaluation that will be evaluated after the given number of seconds, potentially repeating if loop=TRUE. After the expression has evaluated the 'then' function will get called with the result of the expression and the server object as arguments.

remove_time(id)

Removes the timed evaluation identified by the id (returned when adding the evaulation)

delay(expr, then)

As time except the expr is evaluated immediately at the end of the loop cycle

remove_delay(id)

Removes the delayed evaluation identified by the id

async(expr, then)

As delay and time except the expression is evaluated asynchronously. The progress of evaluation is checked at the end of each loop cycle

remove_async(id)

Removes the async evaluation identified by the id. The evaluation is not necessarily stopped but the then function will not get called.

set_client_id_converter(converter)

Sets the function that converts an HTTP request into a specific client id

test_request(request)

Test the result of recieving a specific HTTP request

test_header(request)

Test the result of recieving a specific HTTP header

test_message(request, binary, message, withClose = TRUE)

Test the result of recieving a message over websocket and potentially closing the connection afterwards

test_websocket(request, message)

Test the result of sending a message over websocket

Examples

# Create a New App
app <- Fire$new()
app$port <- 4689

# Setup the data everytime it starts
app$on('start', function(server, ...) {
    server$set_data('visits', 0)
    server$set_data('cycles', 0)
})

# Count the number of cycles
app$on('cycle-start', function(server, ...) {
    server$set_data('cycles', server$get_data('cycles') + 1)
})

# Count the number of requests
app$on('before-request', function(server, ...) {
    server$set_data('visits', server$get_data('visits') + 1)
})

# Handle requests
app$on('request', function(server, ...) {
    list(
        status = 200L,
        headers = list('Content-Type' = 'text/html'),
        body = paste('This is indeed a test. You are number', server$get_data('visits'))
    )
})

# Show number of requests in the console
app$on('after-request', function(server, ...) {
    message(server$get_data('visits'))
    flush.console()
})

# Terminate the server after 300 cycles
app$on('cycle-end', function(server, ...) {
    if (server$get_data('cycles') > 300) {
        message('Ending...')
        flush.console()
        server$extinguish()
    }
})

# Be polite
app$on('end', function(server) {
    message('Goodbye')
    flush.console()
})

## Not run: 
# app$ignite(showcase = TRUE)
# ## End(Not run)