Migrate one site out a multisite.

We where asked to host a site. But then it turned out that site was part of a bigger multisite. So after I got all files & db of the complete site I needed to clean it up and only keep the requested site left.

The quick and dirty steps:

  • Don’t change the DNS until you’re done testing.

Webhosting settings

  • Import all files on the server
  • Import the database and change the db settings in wp-config.php.
  • Locally add the domain to the hosts file So I didn’t need to change urls
  • delete all sites using wp site delete SITE_ID
  • Only keep site 1 (the primary you can’t delete) and site 12 (the site ID I needed)

Rename the tables

  • Rename the site 1 tables in mysql RENAME TABLE `amsterda_db`.`wp_links` TO `amsterda_db`.`wp_BACKUP_links`;
  • Rename the site 12 tables to the normal tables RENAME TABLE `amsterda_db`.`wp_12_links` TO `amsterda_db`.`wp_links`;
  • Make sure you only rename the site tables, don’t rename wp_blogs and other multisite tables

Update the url

  • In wp_blogs delete the record of site 12 and change the name to the new main site in wp_blogs.domain. And rename the url inside wp_site.
  • Also cleanup the wp_blog_versions.
  • In wp-config.php change the constant DOMAIN_CURRENT_SITE
  • Search the database for all mentions of the old mainsite. This is a per case check what should be done.
    Links in posts are probably fine. The old url in the wp_options maybe not.

Permissions and roles

  • In the wp_options table search for wp_user_roles as option_name. If this record is not present. Search it in the wp_BACKUP_options and create the record manually.
  • Permissions are still set for site 12 fix that using wp search-replace wp_12_ wp_ wp_usermeta

Test

  • Test your site. At least test uploads, permalinks, creating/updating pages
  • The normal steps usually when deploying a new site.
  • Think about things that might differ on this inherent setup.

Live

  • switch DNS
  • SSL

After the first week

  • Delete all wp_BACKUP_* tables
  • Check for unneeded plugins
  • Check for unneeded users.
  • Possible you should cleanup the uploads folder of old sites, although there may be links to those uploads.

Of course it would be even better to remove the multisite setup. But I was out of time. And I still would have done these steps first.

PHP interface type hinting

In interfaces you can force the return type

interface InterfaceTest {
    function GetSingleEntity(): Entity;
    function GetEntitySet() : Entity[];
}

GetEntitySet should return a array containing Entities. But this kind of syntax is not allowed.
You could just change it to only return an array, but the forcing of the class is the most powerful.
The best is to create a wrapper class for the entities, best would be to use an Iterator.

sed command line tool

sed is not new for me. But it’s such a versatile tool. And I always have trouble finding the precice syntax I need. So here is a collection of examples. It probably will grow in the years.

Replace the home dir with ~.

COMPACT=$(echo ${HOME} | sed "s#${HOME}#~#g")

Replace %SALT% with the variable $SALT in the file wp-config.php

sudo sed -i -E "s/%SALT%/$SALT/g"  "wp-config.php"

VVV provision single site

For the last month and a half I’ve started using vvv, and it works like a charm.
As I’m setting up a lot of sites I have to run provision a lot.
And that is quite a heavy operation in vvv because it pretty much checks every thing.

Luckily there is also a way to provision a single site.

vagrant provision --provision-with=site-example

Where site-example is the same as the site key in vvv-custom.yml.

wp cli output format with –porcelain

wp db export

Will output something like Succes: Exported to 'dbname-2018-09-16-2790c11.sql'
Often you need the filename.

--porcelain flag to the rescue!

wp db export --porcelain
dbname-2018-09-16-2790c11.sql

This will work on a lot of commands that have one item output.
Stuff like wp post create ....
Here is a complete list of commands that have the –porcelain flag

Commands that output more items usually have a --format flag to handle output.

Declare a variable to a bash script runtime

In the past I’ve did a post about checking if a bash argument is set.
This is different, This way you can pass through a named variable.

    TEST='pass it on' ./testscript.sh

If you do this $TEST will be set inside the ./testscript.sh bash script.
Like the normal arguments you probably would like to validate them inside the bash script.
The main plus side is that you can put arguments in any order and exclude arguments.
It might also be easier to read as you can see the arguments name.

A bit more advanced. You can override global variables for that script run.
Variables like $PWD and $PATH, be careful.

Example script: ./testscript.sh

#!/usr/bin/env bash

if [ ! -z $TEST ]; then
    echo "var is set to '$TEST'";
else
    echo "var is unset";
fi
Posted in TIL

Global git ignore

A new laptop a new change to optimize stuff. And this is one I should have done years ago.
There are files you always want to avoid. The infamous .DS_Store file comes to mind.

On ubuntu just add whatever you want to exclude to ~/.config/git/ignore

Posted in TIL

Copy files/folders over ssh

Sometimes you just want to copy files from a remote server, and you want it often and quick. Stuff like a DB dump.
You could startup your (s)ftp client and browse to it. Or you could just grap it with ssh.

Download one file

scp -user@hostname.com:/full/path/to/dump.xml /local/path/to/Downloads

Download a whole folder

scp -r user@hostname.com:/full/path/to/folder /local/path/to/Downloads