Fix rstats build (#158)

http://b/185379627

Author: Philmod

Dockerfile

@@ -34,16 +34,15 @@ RUN apt-get install -y libhdf5-dev && \
     /tmp/clean-layer.sh
 
 RUN apt-get install -y libzmq3-dev python-pip default-jdk && \
-    apt-get install -y python-dev libcurl4-openssl-dev && \
+    apt-get install -y python-dev libcurl4-openssl-dev libssl-dev && \
     pip install jupyter pycurl && \
     # Install older tornado - https://github.com/jupyter/notebook/issues/4437
     pip install "tornado<6" && \
     # to avoid breaking UI change, pin the jupyter notebook package
     # the latest version also has a regression on the NotebookApp.ip option
     # see: https://www.google.com/url?q=https://github.com/jupyter/notebook/issues/3946&sa=D&usg=AFQjCNFieP7srXVWqX8PDetXGfhyxRmO4Q
     pip install notebook==5.5.0 && \
-    # Pin nbconvert b/170301227
-    pip install nbconvert==5.6.1 && \
+    pip install nbconvert && \
     R -e 'IRkernel::installspec()' && \
     # Build pyzmq from source instead of using a pre-built binary.
     yes | pip uninstall pyzmq && \

package_installs.R

@@ -2,6 +2,11 @@ library(devtools)
 options(repos = c("CRAN" = "http://cran.us.r-project.org"))
 options(Ncpus = parallel::detectCores())
 
+# Set download method, to avoid the default behavior of using
+# R's internal HTTP implementation, which doesn't support HTTPS connections.
+# https://stackoverflow.com/questions/45061272/r-and-ssl-curl-on-ubuntu-linux-failed-ssl-connect-in-r-but-works-in-curl
+options(download.file.method = "libcurl")
+
 # Install the lightGBM installer package
 install_github("Laurae2/lgbdl")
 lgbdl::lgb.dl(compiler = "gcc", commit = "tags/v2.3.1")
@@ -47,4 +52,4 @@ library(torch)
 install_torch(reinstall = TRUE)
 
 # The R Keras package must be reinstalled after installing it in the python virtualenv.
-install.packages("keras")
+install_version("keras", version = "2.3.0.0", ask=FALSE)