Expand validation docs to include new validators and add examples

en/docs/validations.md

@@ -1,4 +1,5 @@
 # Validations
+## Introduction to Validations
 
 Within a model class, you can setup validations.  Validations let you restrict the types of data that can be stored in a model.  Validations are mostly useful for the ```store``` collection, though they can be used elsewhere.
 
@@ -9,12 +10,14 @@ At the moment, we have the following validations (with more on the way):
 - email
 - format
 - numericality
+- inclusion
 - phone number
 - unique
 - type
 
 See [this folder](https://github.com/voltrb/volt/tree/master/lib/volt/models/validators) for more info on the validators.
 
+Validators should be called at the top of your model classes, and generally have this format:
 ```ruby
 class Info < Volt::Model
   validate :name, length: 5
@@ -30,6 +33,84 @@ When ```save!``` on a buffer with validations is called, the following occurs:
 3. If all validations pass, the data is saved to the database and the promise is resolved on the client.
 4. The data is synced to all other clients.
 
+## Validation Examples
+- length
+```ruby
+class Info < Volt::Model
+  # Pass a number for the minimum length
+  validate :first_name, length: 5
+  # or
+  # pass an array with min and max
+  validate :last_name, length: {minimum: 5, maximum: 10}
+end
+```
+
+- present
+```ruby
+class Info < Volt::Model
+  validate :name, present: true
+end
+```
+
+- email
+```ruby
+class Info < Volt::Model
+  validate :email, email: true
+end
+```
+
+- format
+```ruby
+class Info < Volt::Model
+  # takes an hash with keys with: and message:.
+  validate :name, format: { with: /.+@.+/, message: 'must include an @ symbol' }
+end
+```
+
+- numericality
+```ruby
+class Info < Volt::Model
+  # Pass true to only validate it's a number
+  validate :name, numericality: true
+  # Pass a hash with :gt, :lt, :lte, or :gte to specify a range
+  validate :name, numericality: {gt: 5, lte: 10}
+end
+```
+
+- inclusion
+```ruby
+class Info < Volt::Model
+  # pass an array to validate inclusion in the array
+  validate :name, inclusion: ['red', 'blue', 'green', 'purple']
+  # or specify a custom message by passing a hash with in: and message: keys
+  validate :name, inclusion: {in: ['red', 'blue', 'green', 'purple'], message: 'Must be in the list of colors' }
+end
+```
+
+- phone number
+```ruby
+class Info < Volt::Model
+  # pass true to validate U.S.-style phone numbers
+  validate :name, phone_number: true
+  # or pass a hash with with: and message: keys
+  validate :phone, phone_numbe: {with: /\d-\d+/, message: 'Must be a phone number in the format...'}
+end
+```
+
+- unique
+```ruby
+class Info < Volt::Model
+  validate :name, unique: true
+end
+```
+
+- type
+```ruby
+class Info < Volt::Model
+  validate :name, String #Valid options are currently String and Numeric. Volt::Boolean is available but unsupported.
+end
+```
+
 ## Custom Validations
 
 You can create a one off custom validation by passing a block to validate: