Add post: rails gen model be specific

content/posts/2015-11-27-rails-generate-model-be-specific.md

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+date = "2015-11-27"
+title = "Rails generate model: be specific"
+tags = ["rails"]
+description = "Rails offers some very useful generators, one of which creates new model, including migrations. But did you know you can get into the specifics right from the command line?"
+slug = "rails-generate-model-be-specific"
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+
+Rails can generate a lot of things for you. Personally I use `generate model` often to quickly setup a new model, including test files and a database migration.
+In its simplest form it looks like this:
+
+    rails generate product
+
+This will get you started with a _naked_ `Product` model. To make things easier, you can also supply attribute names:
+
+    rails generate product name description:text 
+
+Optionally, you can tell the generator what _type_ of attribute you want. You can choose from the same types as you'd normally use in your migration:
+
+ * `integer`
+ * `primary_key`
+ * `decimal`
+ * `float`
+ * `boolean`
+ * `binary`
+ * `string`
+ * `text`
+ * `date`
+ * `time`
+ * `datetime`
+
+Now, that's not where it ends. Here are some more useful tricks:
+
+### Associations
+
+You can specify that your model _references_ another. Our `Product` might _belong_to_ a `Category`.
+
+    rails generate product category:references
+
+This generates the `category_id` attribute automatically. In some cases you might want to use a _polymorphic_ relation instead, no problem:
+
+    rails generate product supplier:references{polymorphic}
+
+### Limits
+
+For `string`, `text`, `integer` and `binary` fields, you can set the limit by supplying it in curly braces:
+
+    rails generate product sku:string{12}
+
+For `decimal` you must supply two values for precision and scale:
+
+    rails generate product price:decimal{10,2}
+
+### Indices / Indexes
+
+You can also set indices (unique or not) on specific fields as well:
+
+    rails generate product name:string:index
+    rails generate product sku:string{12}:uniq
+    rails generate product supplier:references{polymorphic}:index
+
+### Password digests and tokens
+
+If you want to store password digests using `has_secure_password`, you can also use the `digest` type.
+
+    rails generate user password:digest
+
+And the same goes for `has_secure_token`.
+
+    rails generate user auth_token:token
+
+That's it. Happy generating.