Package 'webdeveloper'

Creates HTML option tags for each position of a list of values and labels by calling HTML5::option(), returning a string of HTML to pass to a select tag through HTML5::select().

Description

Creates HTML option tags for each position of a list of values and labels by calling HTML5::option(), returning a string of HTML to pass to a select tag through HTML5::select().

Usage

create_options(x, selected = c(), add_blank = FALSE)

Arguments

x	A vector which will become the value/label for each option. If named, names become values.
selected	A value in the vector passed to mark as the initially selected option in the select tag.
add_blank	Boolean, If TRUE, adds a blank option to the top of x.

Value

A string, with an option tag each row of x.

Examples

create_options(
x = c("New York", "Los Angeles", "Chicago"),
selected = "Chicago"
)

---

Replace placeholder variables in a HTML document string.

Description

Replace placeholder variables in a HTML document string.

Usage

dynamicTemplate(x, replacements = c())

Arguments

x	HTML string with placeholder variables that need to be replaced.
replacements	A named vector or named list. Names should match a template variable acting as a placeholder in a HTML document string and values should be the text to replace the placeholders with.

Value

A string of HTML with placeholder values replaced.

Examples

dynamicTemplate(
x = html(body(templateVar("body_var"))),
replacements = c("%%rvar-body_var%%" = div(p("body replacement")))
)

---

Replace placeholder variables in a HTML document string, after reading the file into R.

Description

Replace placeholder variables in a HTML document string, after reading the file into R.

Usage

dynamicTemplate2(file, replacements = c())

Arguments

file	Filepath of the HTML file with placeholder variables that need to be replaced.
replacements	A named vector or named list. Names should match a template variable acting as a placeholder in a HTML document string and values should be the text to replace the placeholders with.

Value

A string of HTML with placeholder values replaced.

Examples

tmp <- tempfile()
writeLines(html(body(templateVar("body_var"))), con = tmp)
dynamicTemplate2(file = tmp, replacements = c("%%rvar-body_var%%" = div(p("body replacement"))))

---

Stop HTTP server(s) by calling httpuv::stopServer() or httpuv::stopAllServers().

Description

Stop HTTP server(s) by calling httpuv::stopServer() or httpuv::stopAllServers().

Usage

endServer(x = NULL, all = FALSE)

Arguments

x	A server object that was previously returned from serveHTTP.
all	TRUE/FALSE, if TRUE, calls httpuv::stopAllServers.

Value

Nothing.

Examples

endServer(all = TRUE)

---

Find the names of any placeholder variables that exist in a HTML document string.

Description

Find the names of any placeholder variables that exist in a HTML document string.

Usage

findTemplateVars(x)

Arguments

x	HTML string to check for placeholder.

Value

A vector of the names of template vars found in the HTML string.

Examples

findTemplateVars(x = html(body(templateVar("body_var"))))

---

Add a prefix and suffix to an id

Description

Add a prefix and suffix to an id

Usage

idAddAffixes(prefix, id, suffix, prefix_sep = "X", suffix_sep = "-")

Arguments

prefix	A string, the prefix to add.
id	A string to add a prefix and suffix to.
suffix	A string, the suffix to add.
prefix_sep	A string, the prefix separator to use. This should be different than suffix_sep.
suffix_sep	A string, the suffix separator to use. This should be different than prefix_sep.

Value

A string.

Examples

idAddAffixes("group1", "example", 1)

---

Add a prefix to an id

Description

Add a prefix to an id

Usage

idAddPrefix(prefix, id, sep = "X")

Arguments

prefix	A string, the prefix to add.
id	A string to add a prefix to.
sep	A string, the separator to use.

Value

A string.

Examples

idAddSuffix("example", 1)

---

Add a suffix to an id

Description

Add a suffix to an id

Usage

idAddSuffix(id, suffix, sep = "-")

Arguments

id	A string to add a suffix to.
suffix	A string, the suffix to add.
sep	A string, the separator to use.

Value

A string.

Examples

idAddSuffix("example", 1)

---

Remove a prefix and suffix from an id

Description

Remove a prefix and suffix from an id

Usage

idParseAffixes(id, split = "X|-")

Arguments

id	A string to remove a prefix and suffix from.
split	A regular expression to use for splitting the prefix and suffix from the id.

Value

A named vector, with prefix, id, and suffix returned in that order.

Examples

idParseAffixes(idAddAffixes("group1", "example", 1))

---

Remove a prefix from an id

Description

Remove a prefix from an id

Usage

idParsePrefix(id, split = "X", position = 2)

Arguments

id	A string to remove a prefix from.
split	A string, the separator to use for splitting the id.
position	A integer vector, the position of the split string to return.

Value

A vector.

Examples

idParsePrefix(idAddPrefix("example", 1))

---

Remove a suffix from an id

Description

Remove a suffix from an id

Usage

idParseSuffix(id, split = "-", position = 1)

Arguments

id	A string to remove a suffix from.
split	A string, the separator to use for splitting the id.
position	A integer vector, the position of the split string to return.

Value

A vector.

Examples

idParseSuffix(idAddSuffix("example", 1))

---

Parse the content type header string to return the content type and boundary

Description

Parse the content type header string to return the content type and boundary

Usage

parseContentTypeHeader(x)

Arguments

x	A string containing the content type header.

Value

A named list with "content_type" and "boundary" if boundary is present.

Examples

parseContentTypeHeader("application/x-www-form-urlencoded")

---

Parse a HTTP request

Description

Parse a HTTP request

Usage

parseHTTP(x, content_type_header = NULL, consolidate = TRUE)

Arguments

x	The body of the HTTP request
content_type_header	A string containing the content type header.
consolidate	TRUE/FALSE, if TRUE, consolidates items with the same name.

Value

A named list.

Examples

parseHTTP("?form_id=example&col_name=Test+String", "application/x-www-form-urlencoded")

---

Parse multi-part form data

Description

Parse multi-part form data

Usage

parseMultiPartFormData(x, boundary)

Arguments

x	A vector.
boundary	A string, the boundary used for the multi-part form data

Value

A named list.

Examples

parseMultiPartFormData(
x = c(
  "------WebKitFormBoundaryfBloeH49iOmYtO5A",
  "Content-Disposition: form-data; name=\"form_name\"",
  "",
  "Example",
  "------WebKitFormBoundaryfBloeH49iOmYtO5A",
  "Content-Disposition: form-data; name=\"form_id\"",
  "",
  "test",
  "------WebKitFormBoundaryfBloeH49iOmYtO5A",
  "Content-Disposition: form-data; name=\"desktop_file\"; filename=\"limit_type.csv\"",
  "Content-Type: text/csv",
  "",
  "limit_type",
  "Aggregate",
  "Occurrence",
  "------WebKitFormBoundaryfBloeH49iOmYtO5A--"
),
boundary = parseContentTypeHeader(
"multipart/form-data; boundary=----WebKitFormBoundaryfBloeH49iOmYtO5A")[['boundary']]
)

---

Helper function for parseMultiPartFormData

Description

Helper function for parseMultiPartFormData

Usage

parseMultiPartFormParams(x)

Arguments

x	A vector, a chunk of multi-part form data to parse.

Value

A named list.

Examples

parseMultiPartFormParams(c("Content-Disposition: form-data; name=\"form_name\"", "", "Example"))

---

Parse a query string

Description

Parse a query string

Usage

parseQueryString(x, split = "&", consolidate = TRUE)

Arguments

x	A string containing the query string.
split	A string, the character to split by.
consolidate	TRUE/FALSE, if TRUE, consolidates items with the same name.

Value

A named list.

Examples

parseQueryString("?form_id=example&col_name=Test+String")

---

Conveniently create HTTP server using httpuv::startServer() or httpuv::runServer().

Description

Conveniently create HTTP server using httpuv::startServer() or httpuv::runServer().

Usage

serveHTTP(
  host = "127.0.0.1",
  port = 5001,
  persistent = FALSE,
  async = FALSE,
  static = list(),
  dynamic = list(),
  lapply_staticPath = TRUE,
  static_path_options = list(indexhtml = TRUE, fallthrough = FALSE, html_charset =
    "utf-8", headers = list(), validation = character(0), exclude = FALSE)
)

Arguments

host	A string that is a valid IPv4 or IPv6 address that is owned by this server, which the application will listen on. "0.0.0.0" represents all IPv4 addresses and "::/0" represents all IPv6 addresses. Refer to host parameter of httpuv::startServer() for more details.
port	The port number to listen on. Refer to port parameter of httpuv::startServer() for more details.
persistent	TRUE/FALSE. If FALSE, calls httpuv::startServer(), which returns back to the R session (and would therefore not work with launching a persistent server through a system service as the R session would continue and likely exit/end). If TRUE, calls httpuv::runServer(), which does not return to the R session unless an error or interruption occurs and is suitable for use with system services to start or stop a server.
async	TRUE/FALSE, if TRUE, dynamic path requests will be served asynchronously using multicore evaluation, if possible. This is an advanced option and might make it more confusing to debug your app.
static	A named list, names should be URL paths, values should be paths to the files to be served statically (such as a HTML file saved somewhere) or staticPath objects if lapply_staticPath is FALSE.
dynamic	A named list, names should be URL paths, values should be named alists (use alist instead of list) with alist names equaling a HTTP method (such as "GET" or "POST") and the values being expressions that when evaluated return a named list with valid entries for status, headers, and body as specified by httpuv::startServer(). Refer to httpuv::startServer() for more details on what can be returned as the response. ex. list("/" = alist("GET" = get_function(req), "POST" = post_function(req)))
lapply_staticPath	TRUE/FALSE, if TRUE, httpuv::staticPath will be applied to each element of static to create staticPath objects.
static_path_options	A named list, passed to httpuv::staticPathOptions.

Details

serveHTTP is a convenient way to start a HTTP server that works for both static and dynamically created pages. It offers a simplified and organized interface to httpuv::startServer()/httpuv::runServer() that makes serving static and dynamic pages easier. For dynamic pages, the expression evaluated when a browser requests a dynamically served path should likely be an expression/function that has "req" as a parameter. Per the Rook specification implemented by httpuv, "req" is the R environment in which browser request information is collected. Therefore, to access HTTP request headers, inputs, etc. in a function served by a dynamic path, "req" should be a parameter of that function. For the dynamic parameter of serveHTTP, list("/" = alist("GET" = get_homepage(req))) would be a suitable way to call the function get_homepage(req) when the root path of a website is requested with the GET method. The req environment has the following variables: request_method = req$REQUEST_METHOD, script_name = req$SCRIPT_NAME, path_info = req$PATH_INFO, query_string = req$QUERY_STRING, server_name = req$SERVER_NAME, server_port = req$SERVER_PORT, headers = req$HEADERS, rook_input = req[["rook.input"]]$read_lines(), rook_version = req[["rook.version"]]$read_lines(), rook_url_scheme = req[["rook.url_scheme"]]$read_lines(), rook_error_stream = req[["rook.errors"]]$read_lines()

Value

A HTTP web server on the specified host and port.

Examples

# Run both functions and go to http://127.0.0.1:5001/ in a web browser
get_example <- function(req){

html <- doctype(
html(
head(),
body(
h1("Hello"),
p("Here is a list of some of the variables included in the req environment
that were associated with this request:"),
ul(
li(paste0("req$REQUEST_METHOD = ", req$REQUEST_METHOD)),
li(paste0("req$SCRIPT_NAME = ", req$SCRIPT_NAME)),
li(paste0("req$PATH_INFO = ", req$PATH_INFO)),
li(paste0("req$QUERY_STRING = ", req$QUERY_STRING)),
li(paste0("req$SERVER_NAME = ", req$SERVER_NAME)),
li(paste0("req$SERVER_PORT = ", req$SERVER_PORT))
),
p("You can use parseQueryString to deal with inputs passed through query strings as
well as passed through the input stream."),
p("params <- parseQueryString(req[[\"rook.input\"]]$read_lines()) will give you a
named list of parameters. See also parseHTTP.")
)
)
)
return(
list(
status = 200L,
headers = list('Content-Type' = 'text/html'),
body = html
)
)
}

serveHTTP(
host = "127.0.0.1",
port = 5001,
persistent = FALSE,
static = list(),
dynamic = list(
"/" = alist(
"GET" = get_example(req)
)
)
)

---

Create a string to use as a placeholder variable in a HTML document.

Description

Create a string to use as a placeholder variable in a HTML document.

Usage

templateVar(x)

Arguments

x	Name of placeholder.

Value

A string.

Examples

templateVar("my_dynamic_var")

---