Harden Docker torch CI builds, add save_ml_model return_model, and refresh LPS ML demos.

.dockerignore

@@ -6,6 +6,7 @@ docker/*
 !docker/plumber.R
 !docker/server.R
 !docker/verify-r-deps.R
+!docker/install-torch.R
 tests/
 *.Rproj
 *.md

.github/workflows/docker-compose-workflow.yml

@@ -7,10 +7,14 @@ on:
 jobs:
     test:
         runs-on: ubuntu-22.04
+        timeout-minutes: 360
         steps:
             - name: Check out code
               uses: actions/checkout@v6
 
+            - name: Set up Docker Buildx
+              uses: docker/setup-buildx-action@v4
+
             - name: Login to Docker Hub
               uses: docker/login-action@v4
               with:
@@ -22,8 +26,11 @@ jobs:
               with:
                   context: .
                   file: ./docker/Dockerfile
+                  platforms: linux/amd64
                   push: true
                   tags: brianpondi/openeocraft:latest
+                  cache-from: type=gha
+                  cache-to: type=gha,mode=max
 
             - name: Run docker compose
               run: docker compose up -d

docker/Dockerfile

@@ -41,11 +41,13 @@ RUN R -e "install.packages(c('devtools'), repos='https://cloud.r-project.org')"
 RUN R -e "install.packages(c('gdalcubes','plumber','useful','s2','sf','rstac','geojsonsf', 'jsonlite', 'base64enc', 'ids', 'callr' , 'sits'), repos='https://cloud.r-project.org')"
 
 # Install torch's Lantern library (required for deep learning models like TempCNN).
-# TORCH_INSTALL=1 auto-confirms the interactive prompt.
-# The second R call fails the build immediately if install_torch() left Lantern
-# absent — without it, install failures are silent and only surface at runtime.
-RUN TORCH_INSTALL=1 R -e "torch::install_torch()" && \
-    R -e "t <- torch::torch_tensor(1L); stopifnot(as.numeric(t) == 1L); message('Lantern OK')"
+# TORCH_INSTALL=1 auto-confirms the interactive prompt; CUDA=cpu avoids GPU binary
+# detection on build hosts without NVIDIA drivers. Retries + long timeout help CI
+# survive slow downloads (~170 MB libtorch as of torch 0.17).
+ENV TORCH_INSTALL=1
+ENV CUDA=cpu
+COPY docker/install-torch.R /tmp/install-torch.R
+RUN Rscript /tmp/install-torch.R
 
 
 # create directories

docker/install-torch.R

@@ -0,0 +1,33 @@
+#!/usr/bin/env Rscript
+# Install torch Lantern during Docker build with retries for flaky CI downloads.
+
+Sys.setenv(TORCH_INSTALL = "1", CUDA = "cpu")
+
+if (!requireNamespace("torch", quietly = TRUE)) {
+  install.packages("torch", repos = "https://cloud.r-project.org")
+}
+
+max_attempts <- 3L
+ok <- FALSE
+for (attempt in seq_len(max_attempts)) {
+  ok <- tryCatch(
+    {
+      torch::install_torch(timeout = 1800)
+      t <- torch::torch_tensor(1L)
+      stopifnot(as.numeric(t) == 1L)
+      TRUE
+    },
+    error = function(e) {
+      message("install_torch attempt ", attempt, " failed: ", conditionMessage(e))
+      FALSE
+    }
+  )
+  if (ok) break
+  if (attempt < max_attempts) Sys.sleep(60)
+}
+
+if (!ok) {
+  stop("install_torch failed after ", max_attempts, " attempts", call. = FALSE)
+}
+
+message("Lantern OK")