Request
This details the request object, generally the first argument
of the functions passed to paths (app$get("/", \(req, res){})).
Object
Easiest to see what is available is to print the object.
library(ambiorix)
app <- Ambiorix$new()
app$get("/", \(req, res){
print(req)
res$send("Using {ambiorix}!")
})
app$start()
✔ GET "/"
• HEADERS: "image/avif,image/webp,*/*", "gzip, deflate", "en-US,en;q=0.5", "keep-alive",
"localhost:9345", "http://localhost:9345/", "image", "no-cors", "same-origin", and "Mozilla/5.0 (X11;
Linux x86_64; rv:97.0) Gecko/20100101 Firefox/97.0"
• HTTP_ACCEPT: "image/avif,image/webp,*/*"
• HTTP_ACCEPT_ENCODING: "gzip, deflate"
• HTTP_ACCEPT_LANGUAGE: "en-US,en;q=0.5"
• HTTP_CACHE_CONTROL:
• HTTP_CONNECTION: "keep-alive"
• HTTP_COOKIE:
• HTTP_DNT:
• HTTP_HOST: "localhost:9345"
• HTTP_SEC_FETCH_DEST: "image"
• HTTP_SEC_FETCH_MODE: "no-cors"
• HTTP_SEC_FETCH_SITE: "same-origin"
• HTTP_SEC_FETCH_USER:
• HTTP_UPGRADE_INSECURE_REQUESTS:
• HTTP_USER_AGENT: "Mozilla/5.0 (X11; Linux x86_64; rv:97.0) Gecko/20100101 Firefox/97.0"
• httpuv.version 1.6.5
• PATH_INFO: "/favicon.ico"
• QUERY_STRING: ""
• REMOTE_ADDR: "127.0.0.1"
• REMOTE_PORT: "59462"
• REQUEST_METHOD: "GET"
• SCRIPT_NAME: ""
• SERVER_NAME: "127.0.0.1"
• SERVER_PORT: "127.0.0.1"
• CONTENT_LENGTH:
• CONTENT_TYPE:
• HTTP_REFERER: "http://localhost:9345/"
• rook.version: "1.1-0"
• rook.url_scheme: "http"
To access the HEADERS for instance, simple do req$HEADERS.
Bind
In the very early days of ambiorix, the request was a locked environment so
one could only read from it.
Now, the environment is not locked and variables can be added
to the request, e.g.:
req$x <- 1L.Make sure you do not overwrite existing data.
app <- Ambiorix$new()
app$use(\(req, res){
# set
req$user <- "John"
})
app$get("/", \(req, res){
# get
print(req$user)
res$send("Hello {ambiorix}")
})
app$start()
Counter
This is an example of creating a counter; every refresh bumps the counter, using a middleware means we cound visits overall, not just to the main page.
app <- Ambiorix$new()
val <- 0L
app$use(\(req, res){
val <<- val + 1L
req$x <- val
})
app$get("/", \(req, res){
res$send_sprintf(
"Count %s",
req$x
)
})
app$get("/add", \(req, res){
res$send_sprintf(
"Added one!",
)
})
app$start()