docs: Switching to /srv/www from /var/www to be more FHS 3.0 conformat

It's more modern and well supported to use /srv/www now in place of
/var/www.

Change-Id: Icd09ed4d5fb4e2b9b84ddead21313ea1c0a87c91
ref: https://refspecs.linuxfoundation.org/FHS_3.0/fhs/ch03s17.html

doc/source/apache_deployment_guide.rst

@@ -6,92 +6,90 @@ Apache Deployment Guide
 Web Front End Considerations
 ----------------------------
 
-Swift can be configured to work both using an integral web front-end
+Swift can be configured to work both using an integral web front-end and using a
-and using a full-fledged Web Server such as the Apache2 (HTTPD) web server.
+full-fledged Web Server such as the Apache2 (HTTPD) web server. The integral
-The integral web front-end is a wsgi mini "Web Server" which opens
+web front-end is a wsgi mini "Web Server" which opens up its own socket and
-up its own socket and serves http requests directly.
+serves http requests directly. The incoming requests accepted by the integral
-The incoming requests accepted by the integral web front-end are then forwarded
+web front-end are then forwarded to a wsgi application (the core swift) for
-to a wsgi application (the core swift) for further handling, possibly
+further handling, possibly via wsgi middleware sub-components.
-via wsgi middleware sub-components.
 
 client<---->'integral web front-end'<---->middleware<---->'core swift'
 
-To gain full advantage of Apache2, Swift can alternatively be
+To gain full advantage of Apache2, Swift can alternatively be configured to work
-configured to work as a request processor of the Apache2 server.
+as a request processor of the Apache2 server. This alternative deployment
-This alternative deployment scenario uses mod_wsgi of Apache2
+scenario uses mod_wsgi of Apache2 to forward requests to the swift wsgi
-to forward requests to the swift wsgi application and middleware.
+application and middleware.
 
 client<---->'Apache2 with mod_wsgi'<----->middleware<---->'core swift'
 
-The integral web front-end offers simplicity and requires
+The integral web front-end offers simplicity and requires minimal configuration.
-minimal configuration. It is also the web front-end most commonly used
+It is also the web front-end most commonly used with Swift. Additionally, the
-with Swift.
+integral web front-end includes support for receiving chunked transfer encoding
-Additionally, the integral web front-end includes support for
+from a client, presently not supported by Apache2 in the operation mode
-receiving chunked transfer encoding from a client,
+described here.
-presently not supported by Apache2 in the operation mode described here.
 
 The use of Apache2 offers new ways to extend Swift and integrate it with
-existing authentication, administration and control systems.
+existing authentication, administration and control systems. A single Apache2
-A single Apache2 server can serve as the web front end of any number of swift
+server can serve as the web front end of any number of swift servers residing on
-servers residing on a swift node.
+a swift node. For example when a storage node offers account, container and
-For example when a storage node offers account, container and object services,
+object services, a single Apache2 server can serve as the web front end of all
-a single Apache2 server can serve as the web front end of all three services.
+three services.
 
 The apache variant described here was tested as part of an IBM research work.
 It was found that following tuning, the Apache2 offer generally equivalent
-performance to that offered by the integral web front-end.
+performance to that offered by the integral web front-end. Alternative to
-Alternative to Apache2, other web servers may be used, but were never tested.
+Apache2, other web servers may be used, but were never tested.
 
 -------------
 Apache2 Setup
 -------------
-Both Apache2 and mod-wsgi needs to be installed on the system.
+Both Apache2 and mod-wsgi needs to be installed on the system. Ubuntu comes
-Ubuntu comes with Apache2 installed. Install mod-wsgi using:: 
+with Apache2 installed. Install mod-wsgi using::
 
     sudo apt-get install libapache2-mod-wsgi
 
-First, change the User and Group IDs of Apache2 to be those used by Swift.
+First, change the User and Group IDs of Apache2 to be those used by Swift. For
-For example in /etc/apache2/envvars use::
+example in /etc/apache2/envvars use::
 
     export APACHE_RUN_USER=swift
     export APACHE_RUN_GROUP=swift
 
 Create a directory for the Apache2 wsgi files::
 
-    sudo mkdir /var/www/swift
+    sudo mkdir /srv/www/swift
 
-Create a file for each service under /var/www/swift.
+Create a file for each service under /srv/www/swift.
 
-For a proxy service create /var/www/swift/proxy-server.wsgi::
+For a proxy service create /srv/www/swift/proxy-server.wsgi::
 
     from swift.common.wsgi import init_request_processor
     application, conf, logger, log_name = \
         init_request_processor('/etc/swift/proxy-server.conf','proxy-server')
 
-For an account service create /var/www/swift/account-server.wsgi::
+For an account service create /srv/www/swift/account-server.wsgi::
 
     from swift.common.wsgi import init_request_processor
     application, conf, logger, log_name = \
         init_request_processor('/etc/swift/account-server.conf',
                                'account-server')
 
-For an container service create /var/www/swift/container-server.wsgi::
+For an container service create /srv/www/swift/container-server.wsgi::
 
     from swift.common.wsgi import init_request_processor
     application, conf, logger, log_name = \
         init_request_processor('/etc/swift/container-server.conf',
                               'container-server')
 
-For an object service create /var/www/swift/object-server.wsgi::
+For an object service create /srv/www/swift/object-server.wsgi::
 
     from swift.common.wsgi import init_request_processor
     application, conf, logger, log_name = \
         init_request_processor('/etc/swift/object-server.conf',
                                'object-server')
 
-Create a /etc/apache2/conf.d/swift_wsgi.conf configuration file that will
+Create a /etc/apache2/conf.d/swift_wsgi.conf configuration file that will define
-define a port and Virtual Host per each local service.
+a port and Virtual Host per each local service. For example an Apache2 serving
-For example an Apache2 serving as a web front end of a proxy service::
+as a web front end of a proxy service::
 
     #Proxy
     NameVirtualHost *:8080
@@ -101,20 +99,19 @@ For example an Apache2 serving as a web front end of a proxy service::
         LimitRequestBody 5368709122
         WSGIDaemonProcess proxy-server processes=5 threads=1
         WSGIProcessGroup proxy-server
-        WSGIScriptAlias / /var/www/swift/proxy-server.wsgi
+        WSGIScriptAlias / /srv/www/swift/proxy-server.wsgi
         LimitRequestFields 200
         ErrorLog /var/log/apache2/proxy-server
         LogLevel debug
         CustomLog /var/log/apache2/proxy.log combined
     </VirtualHost>
 
-Notice that when using Apache the limit on the maximal object size should
+Notice that when using Apache the limit on the maximal object size should be
-be imposed by Apache using the LimitRequestBody rather by the swift proxy.
+imposed by Apache using the LimitRequestBody rather by the swift proxy. Note
-Note also that the LimitRequestBody should indicate the same value
+also that the LimitRequestBody should indicate the same value as indicated by
-as indicated by max_file_size located in both 
+max_file_size located in both /etc/swift/swift.conf and in /etc/swift/test.conf.
-/etc/swift/swift.conf and in /etc/swift/test.conf.
+The Swift default value for max_file_size (when not present) is 5368709122. For
-The Swift default value for max_file_size (when not present) is 5368709122.
+example an Apache2 serving as a web front end of a storage node::
-For example an Apache2 serving as a web front end of a storage node::
 
     #Object Service
     NameVirtualHost *:6200
@@ -123,7 +120,7 @@ For example an Apache2 serving as a web front end of a storage node::
         ServerName object-server
         WSGIDaemonProcess object-server processes=5 threads=1
         WSGIProcessGroup object-server
-        WSGIScriptAlias / /var/www/swift/object-server.wsgi
+        WSGIScriptAlias / /srv/www/swift/object-server.wsgi
         LimitRequestFields 200
         ErrorLog /var/log/apache2/object-server
         LogLevel debug
@@ -137,7 +134,7 @@ For example an Apache2 serving as a web front end of a storage node::
         ServerName container-server
         WSGIDaemonProcess container-server processes=5 threads=1
         WSGIProcessGroup container-server
-        WSGIScriptAlias / /var/www/swift/container-server.wsgi
+        WSGIScriptAlias / /srv/www/swift/container-server.wsgi
         LimitRequestFields 200
         ErrorLog /var/log/apache2/container-server
         LogLevel debug
@@ -151,7 +148,7 @@ For example an Apache2 serving as a web front end of a storage node::
         ServerName account-server
         WSGIDaemonProcess account-server processes=5 threads=1
         WSGIProcessGroup account-server
-        WSGIScriptAlias / /var/www/swift/account-server.wsgi
+        WSGIScriptAlias / /srv/www/swift/account-server.wsgi
         LimitRequestFields 200
         ErrorLog /var/log/apache2/account-server
         LogLevel debug
@@ -168,11 +165,10 @@ Edit the tests config file and add::
     web_front_end = apache2
     normalized_urls = True
 
-Also check to see that the file includes max_file_size of the same value as
+Also check to see that the file includes max_file_size of the same value as used
-used for the LimitRequestBody in the apache config file above.
+for the LimitRequestBody in the apache config file above.
 
-We are done.
+We are done. You may run functional tests to test - e.g.::
-You may run functional tests to test - e.g.::
 
     cd ~swift/swift
     ./.functests