This function is still under development and depends heavily on test data in a specific format and whether or not the back-end provider exposes their UDF service endpoint or if you have setup a local UDF service (see notes). The openEO UDF API v0.1.0 had foreseen to ship data and code in a single message and to be interpretable by a computing service a specific format was designed. Usually this whole operation is neatly hidden within the back-end, but if you want to test and debug the code, you need to create such data first. Some examples are available at https://github.com/Open-EO/openeo-r-udf/tree/master/examples/data.
send_udf(
data,
code,
host = "http://localhost",
port = NULL,
language = "R",
debug = FALSE,
user_context = NA,
server_context = NA,
download_info = FALSE,
legacy = FALSE,
...
)file path or a list object with the UDF-API data object
a call object or a file path of the user defined code
URL to the UDF service
(optional) port of the UDF service host
programming language (R or Python) of the source code
(optional) logical - Switch on / off debugging information
list - Context parameter that are shipped from the user into the udf_service
list - Context usually sent from the back-end to trigger certain settings
(optional) logical - Whether or not to print the time taken separately for the download
logical - Whether or not the legacy endpoint is used (default: FALSE)
parameters passed on to httr::content or to be more precise to jsonlite::fromJSON
the textual JSON representation of the result
Hint: If you use a local R UDF service you might want to debug using the 'browser()' function.
The debug options are only available for the R-UDF service. The R UDF-API version has to be of version 0.1.0 (not the old alpha version). You might want to check https://github.com/Open-EO/openeo-r-udf#running-the-api-locally for setting up a local service for debugging.
if (FALSE) {
port = 5555
host = "http://localhost"
script = quote({
all_dim = names(dim(data))
ndvi_result = st_apply(data, FUN = function(X,...) {
(X[8]-X[4])/(X[8]+X[4])
}, MARGIN = all_dim[-which(all_dim=="band")])
all_dim = names(dim(ndvi_result))
min_ndvi = st_apply(ndvi_result,FUN = min, MARGIN = all_dim[-which(all_dim=="t")])
min_ndvi
})
result = send_udf(data = "hypercube.json",code = script,host=host,port=port)
}