Docs for cost

* Adding docs about cost
* Adding cost to json response
* Updating api docs
* Including doc about suggestion

Author: truggeri

app/models/short.rb

@@ -41,7 +41,7 @@ class Short < ApplicationRecord
                         exclusion: { in: RESERVED_SHORTS, message: :reserved }
 
   def marshall
-    { created_at: created_at.iso8601, full_url: full_url, short_url: short_url, token: token }
+    { cost: cost, created_at: created_at.iso8601, full_url: full_url, short_url: short_url, token: token }
   end
 
   private

docs/api-spec.yaml

@@ -7,7 +7,7 @@ info:
   license:
     name: MIT
     url: https://github.com/truggeri/rails-url-shortener/blob/main/LICENSE
-  version: 1.0.0
+  version: 1.0.1
 servers:
 - url: https://short.truggeri.com/
 externalDocs:
@@ -50,12 +50,17 @@ paths:
             application/json:
               schema:
                 required:
+                - cost
                 - created_at
                 - full_url
                 - short_url
                 - token
                 type: object
                 properties:
+                  cost:
+                    type: number
+                    description: The cost of the short in USD
+                    example: 9
                   created_at:
                     type: string
                     description: Date in iso8601 format

docs/design.md

@@ -18,6 +18,13 @@ From the original requirements specification,
 > 1. The project should include an automated test suite.
 > 2. The project should include a README file with instructions for running the web service and its tests. You should also use the README to provide context on choices made during development.
 > 3. The project should be packaged as a zip file or submitted via a hosted git platform (Github, Gitlab, etc).
+>
+> **Additional Requirements**:
+>
+> 1. Calculate a cost for each slug, where consonants cost $1, vowels $2 and any repeated character costs $1 extra.
+> a. ex: goly -> $5, oely -> $6, gole -> $6
+> 2. Add a suggestion service that given a valid hostname (characters only) suggests a slug that has minimal cost.
+> a. ex: goldbelly -> gldb ($4), google -> golg ($6), hi -> hihh ($7)
 
 ## Product Design
 
@@ -174,6 +181,31 @@ This project includes a [root README file](../README.md) which references this d
 
 This project is hosted using [GitHub](https://github.com/) at [https://github.com/truggeri/rails-url-shortener](https://github.com/truggeri/rails-url-shortener).
 
+## Additional Requirements
+
+A later pairing session brought about the following additions.
+
+### Cost Calculation
+
+The cost calculation is done as a [before-validation action on the `Short` model](https://github.com/truggeri/rails-url-shortener/blob/6d94c5c421e59b95427749c15f62b4de91d0f8b8/app/models/short.rb#L34).
+It iterates over each character and tallies a cost per character.
+A slight modification was made to allow for digits and `-_` characters at a cost of $3 each. Reoccurrences are
+handled by a hash for quick access. This cost is then saved to the model to avoid recalculation.
+
+### Suggestion Service
+
+There is a [suggestion service](https://github.com/truggeri/rails-url-shortener/blob/main/app/lib/suggestion.rb)
+that takes in a hostname (such as `google`) and outputs a suggestion at minimal cost.
+This works by breaking the hostname into possible characters (consonants and vowels), then iterating in order of
+
+* Unused consonants ($1 each)
+* Unused vowels ($2 each)
+* Used consonants ($2 each)
+* Used vowels ($3 each)
+
+A random selection is done for each used character to provide unique suggestions. A randomization _could_ be done
+on all characters after the generation too.
+
 ## Future Improvements
 
 To see areas for improvement, [read our documentation](./future_improvements.md).

public/api-spec.yaml

@@ -7,7 +7,7 @@ info:
   license:
     name: MIT
     url: https://github.com/truggeri/rails-url-shortener/blob/main/LICENSE
-  version: 1.0.0
+  version: 1.0.1
 servers:
 - url: https://short.truggeri.com/
 externalDocs:
@@ -50,12 +50,17 @@ paths:
             application/json:
               schema:
                 required:
+                - cost
                 - created_at
                 - full_url
                 - short_url
                 - token
                 type: object
                 properties:
+                  cost:
+                    type: number
+                    description: The cost of the short in USD
+                    example: 9
                   created_at:
                     type: string
                     description: Date in iso8601 format

spec/models/short_spec.rb

@@ -209,7 +209,8 @@
       Timecop.freeze(time) do
         allow(Token).to receive(:encode).with({ iat: object.created_at.to_i, uuid: object.uuid })
                                         .and_return('fake-token')
-        expect(subject).to include(created_at: time.iso8601,
+        expect(subject).to include(cost:       7,
+                                   created_at: time.iso8601,
                                    full_url:   'full-full',
                                    short_url:  'shorty',
                                    token:      'fake-token')