Documentation
Ambiorix
Parameters & Query

Parameters & Query

Ambiorix allows extracting values from the URL using parameters and query strings.

  • Parameters are dynamic parts of the URL, accessible via req$params$param_name.
  • Query strings are key-value pairs appended to the URL (?key=value), accessible via req$query$query_name or req$query[[index]] (if unnamed).

Parameters

Define URL parameters using :<param>, and retrieve them with req$params$<name>.

#' Handle GET at '/books/:category'
#'
#' @export
get_book_category <- \(req, res) {
  html <- tags$h3(
    "Books in category:",
    req$params$category
  )
  res$send(html)
}

app <- Ambiorix$new()
app$get("/books/:category", get_book_category)
app$start()

Example Routes

  • /books/fiction → Displays “Books in category: fiction”
  • /books/math → Displays “Books in category: math”
  • /books/philosophy → Displays “Books in category: philosophy”

Query Strings

Query strings allow passing additional information to a request. These values are parsed into req$query.

library(ambiorix)
library(htmltools)

#' Handle GET at '/greet'
#'
#' @export
say_hello <- \(req, res) {
  html <- tags$h3(
    "Hello,",
    req$query$firstname,
    req$query$lastname
  )

  res$send(html)
}

app <- Ambiorix$new()
app$get("/greet", say_hello)
app$start()

Example Routes

  • /greet?firstname=John&lastname=Coene → Displays “Hello, John Coene”
  • /greet?firstname=Alice&lastname=Smith → Displays “Hello, Alice Smith”
  • /greet?firstname=Marie&lastname=Curie → Displays “Hello, Marie Curie”