Added Docker setup for initial database import

This MR adds the import of an osm.pbf file into an empty database.

Related to https://git.gfz-potsdam.de/dynamicexposure/server-components/compositions/docker-openbuildingmap-import/-/merge_requests/2

\rfc @marius \approve @ds

files/start.sh

@@ -16,7 +16,6 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program. If not, see http://www.gnu.org/licenses/.
 
-set -e
 printf "\nWelcome to the OpenBuildingMap importer\n\n"
 
 main () {
@@ -29,12 +28,12 @@ main () {
   done
 
   # Initiate new or reuse existing database
-  if ! execute_database_command "\c ${OBM_DATABASE_NAME}"; then
+  if execute_database_command "\connect ${OBM_DATABASE_NAME}"; then
+    printf "Reuse existing database: %s\n" "${OBM_DATABASE_NAME}"
+  else
     execute_database_command "CREATE DATABASE ${OBM_DATABASE_NAME};"
     add_database_extensions
     printf "Initiated new database: %s\n" "${OBM_DATABASE_NAME}"
-  else
-    printf "Reuse existing database: %s\n" "${OBM_DATABASE_NAME}"
   fi
 
   # Obtain mapping information for database schema
@@ -42,11 +41,11 @@ main () {
 
   # Import OpenStreetMap data if database is empty
   database_exists=$(psql --host="${OBM_DATABASE_HOST}" --username="${OBM_DATABASE_USER}" "${OBM_DATABASE_NAME}" --tuples-only --command="SELECT CASE WHEN EXISTS (SELECT FROM pg_tables WHERE schemaname = 'public' AND tablename = 'planet_osm_line' LIMIT 1) THEN 'true' ELSE 'false' end;")
-  if ! ${database_exists}; then
-      import_openstreetmap_data
-      printf "OpenStreetMap data has been imported.\n"
-  else
+  if ${database_exists}; then
     printf "Assuming already imported database: %s\n" "${OBM_DATABASE_NAME}"
+  else
+    import_openstreetmap_data
+    printf "OpenStreetMap data has been imported.\n"  
   fi
 }
 
@@ -59,7 +58,7 @@ execute_database_query () {
 }
 
 add_database_extensions () {
-  if psql -h "${OBM_DATABASE_HOST}" -U "${OBM_DATABASE_USER}" -c "\c ${OBM_DATABASE_NAME}"; then
+  if psql -h "${OBM_DATABASE_HOST}" -U "${OBM_DATABASE_USER}" -c "\connect ${OBM_DATABASE_NAME}"; then
     execute_database_query "CREATE EXTENSION postgis;"
     printf " postgis extension added to %s database.\n" "${OBM_DATABASE_NAME}"
     execute_database_query "CREATE EXTENSION hstore;"
@@ -103,7 +102,7 @@ import_openstreetmap_data () {
         --cache-strategy dense \
         "${OBM_IMPORT_FILE}"
   else
-      printf "Error: No import file '%s' has been found.\nGood bye.\n" "${OBM_IMPORT_FILE}"
+      printf "Error: No import file '%s' has been found.\Aborting.\n" "${OBM_IMPORT_FILE}"
       exit 1
   fi
 }