Ruby on Rails, Showing the hashmap array?

Question

I was wondering is there a way to show the hash map array? I'm not sure if its the right terminology? But I wanted to see the columns from the database to see if I'm calling the correct hash keys.

For instance,

created on <%= link_to activity.trackable.list.name, activity.trackable.list %>

I'm not sure if I'm calling the correct names, if I'm getting undefined method? If I need to see if there's a key for .name or .list. I would like to see the array of activity.trackable if there's such thing?

This code is coming from a tutorial in rails cast #407

This is what you want: https://github.com/ctran/annotate_models — AJcodez, May 12 '13 at 01:06
No, you don't... You can just look in the schema file, why pollute all of your models with some quick-to-become-outdated comments? — Brad Werth, May 12 '13 at 01:41

score 0 · Answer 1 · answered May 12 '13 at 01:00

You could do something like:

p activity.trackable.columns

or

p activity.trackable.columns_hash

or

p activity.trackable.column_names

if you want to see more, you could do

p activity.trackable.methods

or

p activity.trackable.respond_to?( :something )

score 0 · Answer 2 · answered May 12 '13 at 05:28

I recommend installing the awesome_print gem

then in rails console you can inspect objects easily

ap activity.trackable

# or

ap Activity.new

see

OR if you are using postgres you can do

psql your_db_development -c "\d activities"

# lists all columns on database table and their types

Ruby on Rails, Showing the hashmap array?

2 Answers2