Failing to get spectral indexes

[Cidree]

Hello,

I am trying to get spectral indexes using the function ee$Image$spectralIndex() without success.

# Load libraries
library(rgee)
library(rgeeExtra)

# Initialize Earth Engine
ee_Initialize()
extra_Initialize()

## Attempt 1: copied from rgee book ----

ds <- 'LANDSAT/LC08/C01/T1_SR'

ee$ImageCollection(ds) %>% 
  ee_ImageCollection_scaleAndOffset() %>% 
  ee_ImageCollection_spectralIndex(c('NDVI', 'GNDVI', 'NDSI'))

# Error in ee_ImageCollection_spectralIndex(., c("NDVI", "GNDVI", "NDSI")) : 
#   could not find function "ee_ImageCollection_spectralIndex"

## Attempt 2: copied from function reference ----

s2_indices <- ee$ImageCollection("COPERNICUS/S2_SR") %>%
  ee$ImageCollection$first() %>%
  ee$Image$preprocess()%>%
  ee$Image$spectralIndex(c("NDVI", "SAVI"))

# Error in EEextra_PYTHON_PACKAGE$QA : 
#   RuntimeError: $ operator is invalid for atomic vectors

## Attempt 3 ----

## Get an image (works)
s2_img <- ee$ImageCollection("COPERNICUS/S2_SR") %>% 
  ee$ImageCollection$first()

## Preprocess (no not work)
ee$Image$preprocess(s2_img)

#Error in EEextra_PYTHON_PACKAGE$Spectral : 
#  RuntimeError: $ operator is invalid for atomic vectors

## Get spectral indexes (do not work)
ee$Image$spectralIndex(s2_img)

#Error in EEextra_PYTHON_PACKAGE$Spectral : 
#  RuntimeError: $ operator is invalid for atomic vectors

I am working with R 4.3.1, RStudio 2023.06.1, rgee version 1.1.7 and rgeeExtra development version.