Merge pull request #105 from nmfs-opensci/eeholmes-dev-1

add check for postbuild

appendix

@@ -84,13 +84,32 @@ ONBUILD RUN echo "Checking for 'install.R" \
 # If a start file exists, put that under ${REPO_DIR}/childimage/start. 
 # This is sourced in ${REPO_DIR}/start
 ONBUILD RUN echo "Checking for 'start'..." \
+        ; cd "${REPO_DIR}/childimage/" \
         ; [ -d binder ] && cd binder \
         ; [ -d .binder ] && cd .binder \
         ; if test -f "start" ; then \
         chmod +x start \
         && cp start ${REPO_DIR}/childimage/start \
         ; fi
 
+# If a postBuild file exists, run it!
+# After it's done, we try to remove any possible cruft commands there
+# leave behind under $HOME - particularly stuff that jupyterlab extensions
+# leave behind.
+ONBUILD RUN echo "Checking for 'postBuild'..." \
+        ; cd "${REPO_DIR}/childimage/" \
+        ; [ -d binder ] && cd binder \
+        ; [ -d .binder ] && cd .binder \
+        ; if test -f "postBuild" ; then \
+        chmod +x postBuild \
+        && ./postBuild \
+        && rm -rf /tmp/* \
+        && rm -rf ${HOME}/.cache ${HOME}/.npm ${HOME}/.yarn \
+        && rm -rf ${NB_PYTHON_PREFIX}/share/jupyter/lab/staging \
+        && find ${CONDA_DIR} -follow -type f -name '*.a' -delete \
+        && find ${CONDA_DIR} -follow -type f -name '*.js.map' -delete \
+        ; fi
+
 # Revert to default user and home as pwd
 USER ${NB_USER}
 WORKDIR ${HOME}