explain.depesz.com

Setup

1. Mojolicious

You have to have Mojolicious installed on your server. Mojolicious is a web framework for Perl. http://mojolicio.us/

Installation can be accomplished with one command line:

curl -L cpanmin.us | perl - -n Mojolicious

See the "Installation" section at http://mojolicio.us/ for details.

2. Perl Dependencies: You will need the following packages installed in your version of Perl:

   DBD::Pg Date::Simple Mail::Sender Pg::Explain Email::Valid

Install the above packages using "cpan" then "i Date::Simple", "i Maill::Sender" &etc.

Note that in case of most current Linux distributions, you can install most of these from binary package repositories. For example, in case of Ubuntu and Debian, you can:

apt-get install libmojolicious-perl libmail-sender-perl libdate-simple-perl libemail-valid-perl

And then only add Pg::Explain via cpan.

3. PostgreSQL

A) Create a new database "explain". This will be were the explain server will store the "users" and "plans" tables in the default schema "public".

B) Run SQL scripts. Log into postgres as postgres. Switch to the "explain" database. Execute the SQL scripts located in the "sql" directory in the following order:

\i create.sql
\i patch-001.sql
\i patch-002.sql

The "create.sql" will create tables in the explain database "public" schema, i.e. "plans" and "users".

B) Create a user role. I use "explaind" [explain daemon] and remember to provides it a password and then configure the explain.json file to reflect this new role and password.

C) Grant all rights to the tables in "explain" to your role "explaind":

 grant all on plans, users to explaind;

D) modify /etc/postgresql-9.3/pg_hba.conf so that it has the server as "127.0.0.1"

local   all             all             127.0.0.1               trust

If you do not want to alter /etc/postgresql-9.3/pg_hba.conf, then you might be able to modify the explain.json.dsn setting to specify the name of the value i n the server column from your /etc/postgresql-9.3/pg_hba.conf file, e.g. "localhost". This alternative approach has not been tested. It would be desirable to install this project with the minimal amount of configuration changes, so I encourage someone to come up with a solution that removes this step "D".

4. Alter configuration file explain.json making sure you have the correct values for your database connection. See companion documentation file explain-json-notes.txt

5. Shell

The explain server runs on port 3000. Make sure port 3000 is available and not in use by another process. You may have to specify a different port, e.g. 3200. I do not know where you do that, probably in Mojolicious.

In the trunk directory for this project, run in a shell:

 ./explain daemon

Then access the web page http://localhost:3000

6. when you access the web page, remember to login and create an account for yourself so that your explain plans will be associated with your account.