Cache permissions error when deploying with Capifony

Question

When I deploy with Capifony a Symfony2 project I get this error message in apache log when accessing a webpage:

PHP Fatal error: Uncaught exception 'RuntimeException' with message 'Failed to write cache file "/var/deploys/acme/releases/20150219150638/app/cache/prod/classes.php"

In order to avoid this, each time I deploy I have to execute chmod 777 -R cache for fixing the permissions, which doesn't seem to me like a good solution.

The cache is set in the writable_dirs option, so I don't know exactly why it gives a permissions error:

set :writable_dirs, ["app/cache", "app/logs", "app/sessions"]

I have the following deploy.rb configuration:

set :stages,        %w(production staging)
set :default_stage, "staging"
set :stage_dir,     "app/config"
require 'capistrano/ext/multistage'

set :application, "Api"
set :domain,      "<my_domain>"
set :deploy_to,   "/var/deploys/acme.com"
set :app_path,    "app"

set :repository,  "git@bitbucket.org:acme/api.git"
set :scm,         :git

set :model_manager, "doctrine"
# Or: `propel`

role :web,        domain
role :app,        domain, :primary => true

set  :keep_releases,  3

# Be more verbose by uncommenting the following line
logger.level = Logger::MAX_LEVEL

# Other options
set :user, "root"
set :use_sudo, false

# Symfony2 specific configuration
set :shared_files, ["app/config/parameters.yml"]
set :shared_children, [app_path + "/logs", web_path + "/uploads", "vendor"]
set :use_composer, true
set :update_vendors, true 
set :writable_dirs, ["app/cache", "app/logs", "app/sessions"]
set :webserver_user, "www-data"
set :permission_method, :chown
set :use_set_permissions, true
set :assets_install, true
set :dump_assetic_assets, true

task :upload_parameters do
  origin_file = "app/config/parameters.yml"
  destination_file = shared_path + "/app/config/parameters.yml"

  try_sudo "mkdir -p #{File.dirname(destination_file)}"
  top.upload(origin_file, destination_file)
end

after "deploy:setup", "upload_parameters"

UPDATE

The cache folder has the following permissions when deployed:

drwxrwxrwx 3 root root 4096 Feb 20 13:13 cache

Inside the cache folder, a prod folder is also created with these permissions:

drwxrwxr-x 7 root root 4096 Feb 20 13:13 prod

UPDATE 2

I use root as user because in the server the user root has my public ssh key. If I set another user in the config, it asks me for root password when deploying. However I have set the webserver_user variable in my config above. Also the user root it's not in the group www-data, should it be?

My capifony version it's 2.8.3. Here is an example of command it executes when setting permissions if chmod_alt is selected as settings permissions method:

getfacl --absolute-names --tabular ...

This error is also generated if I have chmod as setting permissions method.

Although the previous command gives an error, I think the command that provokes the roll back (with chmod_alt) is this one:

`echo stat /var/deploys/acme.devel/releases/20150226123037/app/sessions -c %U`

It generates the following error message (after which it makes a rollback):

cannot stat `/var/deploys/acme.devel/releases/20150226123037/app/sessions': 
No such file or directory

Answer 1

I have set the following parameters in my deploy.rb in order to make it work:

set :use_sudo, true
default_run_options[:pty] = true

And I have removed app/sessions from writable dirs option:

set :writable_dirs, ["app/cache", "app/logs"]