Pastes-Bin/BLOG.md

# Migrations

All migrations go into a single file I'll creatively call `migrations`:

    -- 1 up
    CREATE TABLE IF NOT EXISTS pastes (
             paste_id SERIAL PRIMARY KEY,
           paste_body TEXT
           );
    
    -- 1 down
    DROP TABLE pastes;

Connect to the database and then apply the migrations:

    my $dbh = DBIish.connect:
        'Pg',
        :host<devbussy.swagg.net>,
        :database<pastes_bin>,
        :user<pastes_bin>,
        password => prompt 'enter DB password: ';
    
    my $m = DB::Migration::Simple.new:
        :$dbh,
        :migration-file<migrations>;
    
    $m.migrate: :version<1>;

Get prompted for password for now:

    $ ./bin/pastes-bin
    enter DB password: hogrider69
    line: -- 1 up
    version: 1, direction: up
    line: CREATE TABLE IF NOT EXISTS pastes (
    line:          paste_id SERIAL PRIMARY KEY,
    line:        paste_body TEXT
    line:        );
    line: -- 1 down
    version: 1, direction: down
    line: DROP TABLE pastes;
    initializing db-migrations-simple-meta
    set initial version to 0
    {1 => {down => DROP TABLE pastes;
    , up => CREATE TABLE IF NOT EXISTS pastes (
             paste_id SERIAL PRIMARY KEY,
           paste_body TEXT
           );
    }}
    migrating from version '0' to version '1'
    True migrating 'up' from version '0' to version '1'
    doing 'up' migrations for 1
    executing CREATE TABLE IF NOT EXISTS pastes (
             paste_id SERIAL PRIMARY KEY,
           paste_body TEXT
           )
    Humming-Bird listening on port http://localhost:3000

Let's check on DB:

    $ psql -h devbussy.swagg.net -U pastes_bin
    Password for user pastes_bin: 
    psql (15.3 (Debian 15.3-0+deb12u1))
    SSL connection (protocol: TLSv1.3, cipher: TLS_AES_256_GCM_SHA384, compression: off)
    Type "help" for help.
    
    pastes_bin=> \d
                         List of relations
     Schema |           Name            |   Type   |   Owner    
    --------+---------------------------+----------+------------
     public | db-migrations-simple-meta | table    | pastes_bin
     public | pastes                    | table    | pastes_bin
     public | pastes_paste_id_seq       | sequence | pastes_bin
    (3 rows)
    
    pastes_bin=> \d pastes;
                                     Table "public.pastes"
       Column   |  Type   | Collation | Nullable |                 Default                  
    ------------+---------+-----------+----------+------------------------------------------
     paste_id   | integer |           | not null | nextval('pastes_paste_id_seq'::regclass)
     paste_body | text    |           |          | 
    Indexes:
        "pastes_pkey" PRIMARY KEY, btree (paste_id)

Some mock-up 'model' code:

    use Pastes-Bin::Model::Paste;
    
    # No routes yet just prompt to 'fake it'
    my $new-paste = prompt 'enter a new paste: ';
    Pastes-Bin::Model::Paste.create: $new-paste;

Now test it:

    $ ./bin/pastes-bin 
    enter DB password: hogrider69
    line: -- 1 up
    version: 1, direction: up
    line: CREATE TABLE IF NOT EXISTS pastes (
    line:          paste_id SERIAL PRIMARY KEY,
    line:        paste_body TEXT
    line:        );
    line: -- 1 down
    version: 1, direction: down
    line: DROP TABLE pastes;
    current-version: allrows: [[1]]
    {1 => {down => DROP TABLE pastes;
    , up => CREATE TABLE IF NOT EXISTS pastes (
             paste_id SERIAL PRIMARY KEY,
           paste_body TEXT
           );
    }}
    migrating from version '1' to version '1'
    DB already at version 1
    enter a new paste: testing 123...
    Humming-Bird listening on port http://localhost:3000
    ^C

Now check the DB for the paste:

    pastes_bin=> SELECT * FROM pastes;
     paste_id | paste_body 
    ----------+------------
    (0 rows)
    
    pastes_bin=> SELECT * FROM pastes;
     paste_id |   paste_body   
    ----------+----------------
            1 | testing 123...
    (1 row)

End result:

    use Humming-Bird::Core;
    use Humming-Bird::Middleware;
    use Humming-Bird::Advice;
    use DB::Migration::Simple;
    use DBIish;
    
    # Local libs
    use Pastes-Bin::Model::Paste;
    
    # Logging
    middleware &middleware-logger;
    advice     &advice-logger;
    
    # Database stuff
    my $*dbh = DBIish.connect:
        'Pg',
        :host<devbussy.swagg.net>,
        :database<pastes_bin>,
        :user<pastes_bin>,
        password => prompt 'enter DB password: ';
    
    my $m = DB::Migration::Simple.new:
        :$*dbh,
        :migration-file<migrations>,
        :verbose;
    
    $m.migrate: :version<1>;
    
    # No routes yet just prompt to 'fake it'
    my $new-paste = prompt 'enter a new paste: ';
    Pastes-Bin::Model::Paste.create: $new-paste;