## UCTW V4.0
服务器做了一次迁移，从heroku搬到了GCP
老是坐在heroku也不是办法，虽然部署还算方便，也是免费的机房
但是总想试着部署到自己的服务器上，方便今后的扩展
GCP有一年免费和300美金赠送，而且速度快的可怕
搬迁过程中遇到了很多问题
还好都有解决方法
这里汇总一下内容
方便下次迁移
### 数据库的迁移
heroku线上使用的是postgres
GCP上我打算使用mysql
1. 首先从heroku备份数据库
`heroku pg:backups:capture`
2. 下载最新的备份latest.dump
`heroku pg:backups:download`
3. 将备份还原到本地pg数据库中
`pg_restore --verbose --clean --no-acl --no-owner -h localhost -U myuser -d mydb latest.dump`
4. 用本地pg数据库导出sql
`pg_dump -U myuser -s mydb --inserts --format p -f pg.sql `
5. [pg2mysql](http://www.lightbox.ca/pg2mysql.php)将pg.sql的语句转化为Mysql的语句获得mysql.sql
6. 服务器执行
`rake db:migrate RAILS_ENV=production`
7. 删除mysql.sql中的数据迁移表，然后导入
8. 配置 数据库 自动备份 [详见](y.oschina.net/u/231017/blog/186447)
其实6、7两步是可以简化的，直接导入mysql.sql到mysql中就可以了，不需要rails去建立数据库
### ROR的部署
采用的是nginx+unicorn的配置
#### 编译静态文件
`$ RAILS_ENV=production rake assets:clean`
`$ RAILS_ENV=production rake assets:precompile`
#### 配置文件unicorn.rb
```ruby
module Rails
class <<self
def root
File.expand_path(__FILE__).split('/')[0..-3].join('/')
end
end
end
worker_processes 4
working_directory Rails.root
listen "#{Rails.root}/tmp/sockets/socket", :backlog =>
64
timeout 30
pid "#{Rails.root}/tmp/pids/unicorn.pid"
stderr_path "#{Rails.root}/log/unicorn.log"
stdout_path "#{Rails.root}/log/unicorn.log"
# combine Ruby 2.0.0dev or REE with "preload_app true" for memory savings
# http://rubyenterpriseedition.com/faq.html#adapt_apps_for_cow
preload_app true
GC.respond_to?(:copy_on_write_friendly=) and
GC.copy_on_write_friendly = true
check_client_connection false
before_fork do |server, worker|
# the following is highly recomended for Rails + "preload_app true"
# as there's no need for the master process to hold a connection
defined?(ActiveRecord::Base) and
ActiveRecord::Base.connection.disconnect!
old_pid = "#{server.config[:pid]}.oldbin"
if File.exists?(old_pid) && old_pid != server.pid
begin
sig = (worker.nr + 1) >= server.worker_processes ? :QUIT : :TTOU
Process.kill(sig, File.read(old_pid).to_i)
rescue Errno::ENOENT, Errno::ESRCH
end
end
# Throttle the master from forking too quickly by sleeping. Due
# to the implementation of standard Unix signal handlers, this
# helps (but does not completely) prevent identical, repeated signals
# from being lost when the receiving process is busy.
sleep 1
end
after_fork do |server, worker|
# the following is *required* for Rails + "preload_app true",
defined?(ActiveRecord::Base) and
ActiveRecord::Base.establish_connection
# if preload_app is true, then you may also want to check and
# restart any other shared sockets/descriptors such as Memcached,
# and Redis. TokyoCabinet file handles are safe to reuse
# between any number of forked children (assuming your kernel
# correctly implements pread()/pwrite() system calls)
end
```
#### unicorn的运行方法
`unicorn_rails -c /path/to/app/config/unicorn.rb -D -E production`
#### unicorn的热部署
```bash
sudo kill -USR2 `cat path/to/app/tmp/pids/unicorn.pid`
```
因为unicorn的设置中有多个进程，所以需要多次执行此操作
#### nginx的配置文件
```
upstream app{
server unix:///path/to/app/tmp/sockets/socket;
}
server {
listen 80;
server_name app;
root path/to/app/public;
try_files $uri/index.html $uri.html $uri @app;
location ~ ^/(assets)/ {
expires max;
add_header Cache-Control public;
}
location ~ .*\.(php|sql|asp)?$ {
deny all;
}
location @app {
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $http_host;
proxy_redirect off;
proxy_pass http://app;
}
location ~ .*\.(gif|jpg|jpeg|png|bmp|swf)$
{
expires 30d;
}
location ~ .*\.(js|css)?$
{
expires 1h;
}
access_log logs/app.log;
}
```
### 安装mysql、php、phpmysql
https://www.digitalocean.com/community/tutorials/how-to-install-linux-nginx-mysql-php-lemp-stack-in-ubuntu-16-04
### 搜索引擎优化
添加了sitemap
通过/sitemap.xml访问
添加了百度的统计api
### TODO
1. 数据库的备份到网盘
2. wechat中的投票项目
3. 与微信项目的联动
