feat(start): improve error handling (#4406)

Provide better error messages when something fails.

Author: nijel

start

@@ -7,11 +7,19 @@ set -e
 # Allow sensitive settings to be defined in a file
 # in order to support Docker secrets
 if [ -n "${POSTGRES_PASSWORD_FILE}" ]; then
+    if [ ! -r "$POSTGRES_PASSWORD_FILE" ]; then
+        echo "Error: Password file '$POSTGRES_PASSWORD_FILE' not found or not readable" >&2
+        exit 1
+    fi
     POSTGRES_PASSWORD=$(cat "$POSTGRES_PASSWORD_FILE")
     export POSTGRES_PASSWORD
 fi
 
 if [ -n "${REDIS_PASSWORD_FILE}" ]; then
+    if [ ! -r "$REDIS_PASSWORD_FILE" ]; then
+        echo "Error: Password file '$REDIS_PASSWORD_FILE' not found or not readable" >&2
+        exit 1
+    fi
     REDIS_PASSWORD=$(cat "$REDIS_PASSWORD_FILE")
     export REDIS_PASSWORD
 fi
@@ -22,16 +30,28 @@ if [ -z "$CLIENT_MAX_BODY_SIZE" ]; then
 fi
 
 if [ -n "${WEBLATE_ADMIN_PASSWORD_FILE}" ]; then
+    if [ ! -r "$WEBLATE_ADMIN_PASSWORD_FILE" ]; then
+        echo "Error: Password file '$WEBLATE_ADMIN_PASSWORD_FILE' not found or not readable" >&2
+        exit 1
+    fi
     WEBLATE_ADMIN_PASSWORD=$(cat "$WEBLATE_ADMIN_PASSWORD_FILE")
     export WEBLATE_ADMIN_PASSWORD
 fi
 
 if [ -n "${WEBLATE_EMAIL_HOST_PASSWORD_FILE}" ]; then
+    if [ ! -r "$WEBLATE_EMAIL_HOST_PASSWORD_FILE" ]; then
+        echo "Error: Password file '$WEBLATE_EMAIL_HOST_PASSWORD_FILE' not found or not readable" >&2
+        exit 1
+    fi
     WEBLATE_EMAIL_HOST_PASSWORD=$(cat "$WEBLATE_EMAIL_HOST_PASSWORD_FILE")
     export WEBLATE_EMAIL_HOST_PASSWORD
 fi
 
 if [ -n "${WEBLATE_AUTH_LDAP_BIND_PASSWORD_FILE}" ]; then
+    if [ ! -r "$WEBLATE_AUTH_LDAP_BIND_PASSWORD_FILE" ]; then
+        echo "Error: Password file '$WEBLATE_AUTH_LDAP_BIND_PASSWORD_FILE' not found or not readable" >&2
+        exit 1
+    fi
     WEBLATE_AUTH_LDAP_BIND_PASSWORD=$(cat "$WEBLATE_AUTH_LDAP_BIND_PASSWORD_FILE")
     export WEBLATE_AUTH_LDAP_BIND_PASSWORD
 fi
@@ -248,7 +268,10 @@ esac
 
 if [ $VERSION_CHECK -eq 1 ]; then
     # Fetch server version
-    PGVERSION=$(psql -h "$POSTGRES_HOST" -p "$POSTGRES_PORT" -d "${POSTGRES_DB:-$POSTGRES_DATABASE}" -U "$POSTGRES_USER" -t -A -c 'SHOW server_version_num;')
+    PGVERSION=$(psql -h "$POSTGRES_HOST" -p "$POSTGRES_PORT" -d "${POSTGRES_DB:-$POSTGRES_DATABASE}" -U "$POSTGRES_USER" -t -A -c 'SHOW server_version_num;') || {
+        >&2 echo "Failed to connect to PostgreSQL to determine server version"
+        exit 1
+    }
 
     unset PGPASSWORD
 
@@ -384,7 +407,13 @@ set_real_ip_from ::/0;
     # Calculate number of processes, at least 2, at most 4, depending on CPU cores
     if [ -z "$WEBLATE_WORKERS" ]; then
         PROCESSORS=$(nproc)
-        WEBLATE_WORKERS=$((PROCESSORS < 2 ? 2 : PROCESSORS > 4 ? 4 : PROCESSORS))
+        if [ "$PROCESSORS" -lt 2 ]; then
+            WEBLATE_WORKERS=2
+        elif [ "$PROCESSORS" -gt 4 ]; then
+            WEBLATE_WORKERS=4
+        else
+            WEBLATE_WORKERS="$PROCESSORS"
+        fi
         echo "Auto-scaled to $WEBLATE_WORKERS processes, adjust by setting WEBLATE_WORKERS"
     fi