Upgrading Drupal

Hello
I just upgrade, with Composer, our D 8.3.1 site.

 composer update --with-dependencies
Do not run Composer as root/super user! See https://getcomposer.org/root for details
> DrupalProject\composer\ScriptHandler::checkComposerVersion
Loading composer repositories with package information
Updating dependencies (including require-dev)
Package operations: 0 installs, 1 update, 0 removals

Is it possible to upgrade the RESTful Webservice, Serialization, and Basic HTTP Auth modules in Drupal 7 without upgrading the entire site? Meaning, I would like to install the above mentioned Drupal 8 core modules in a Drupal 7 environment.

Hi,
Is it likely that a Drupal 5.x to 8.x upgrade will require major changes or even a major restructuring of an existing website, or is there an upgrade tool which will make the 5.x to 8.x transition relatively easy?

I've found some 6.x and 7.x to 8.x information, but no experiences starting from 5.x

I understand that this is a rather general question, but thanks for experience remarks & advice related to a 5.x to 8.x upgrade (I'm new to Drupal).

Hi all,
I've just updated a Drupal7 site:

sudo drush up drupal
sudo drush up views
sudo drush up services
sudo drush up media

Now I can see this warning:
Warning: file_put_contents(private:///.htaccess): failed to open stream: "DrupalPrivateStreamWrapper::stream_open" call failed in file_create_htaccess() (line 496 of /var/www/mysite/includes/file.inc).

Which is the problem?

Thank you

cld

CAN SOMEONE KINDLY HELP ME WITH THE ERROR BELOW

EntityFieldQueryException: Unknown field: media_gallery_expose_block in EntityFieldQuery->addFieldCondition() (line 841 of /home/govgm/public_html/motie/includes/entity.inc).

This is a puzzling problem. I work locally on my drupal 8 site and deploy to a production server via Capistrano. I just recently upgraded locally to 8.3.1 and the upgrade went smoothly. I exported the config and committed the code to my git repo as usual. I then deployed to my production server via capistrano. The code deployed without fail. When I attempt to drush cim, i get the following error: