Why is my model not updating in my Rails API? - ruby-on-rails

Question

I am developing an API in Rails and interacting with it from another Rails application. Up to now everything has been working correctly, using POST and GET to authenticate users, create records and retrieve data. But now I'm having trouble getting the PUT operation to update a record. It appears it is calling the API correctly and the API is returning a 200 response, but looking at the logs it doesn't look like Rails is even executing an UPDATE statement. The strangest thing is that there are no errors or warning.
Here is the Log. (Data is faker data so I'm not bothering to redact it)
Started PUT "/affiliates/17" for ::1 at 2019-04-26 17:42:51 -0400
Processing by AffiliatesController#update as HTML
Parameters: {"id"=>"17", "username"=>"teracole", "email"=>"dan#purdy.io", "first_name"=>"Max", "last_name"=>"Max", "company"=>"Dach LLC", "manager_id"=>"3"}
[1m[36mUser Load (0.3ms)[0m [1m[34mSELECT "users".* FROM "users" WHERE "users"."id" = $1 LIMIT $2[0m [["id", 2], ["LIMIT", 1]]
↳ app/controllers/application_controller.rb:12
[1m[36mAffiliate Load (0.2ms)[0m [1m[34mSELECT "affiliates".* FROM "affiliates" WHERE "affiliates"."id" = $1 LIMIT $2[0m [["id", 17], ["LIMIT", 1]]
↳ app/controllers/affiliates_controller.rb:50
[1m[35m (0.1ms)[0m [1m[35mBEGIN[0m
↳ app/controllers/affiliates_controller.rb:31
[1m[36mAffiliate Exists (0.3ms)[0m [1m[34mSELECT 1 AS one FROM "affiliates" WHERE "affiliates"."username" = $1 AND "affiliates"."id" != $2 LIMIT $3[0m [["username", "tera.cole"], ["id", 17], ["LIMIT", 1]]
↳ app/controllers/affiliates_controller.rb:31
[1m[35m (0.1ms)[0m [1m[35mCOMMIT[0m
↳ app/controllers/affiliates_controller.rb:31
Completed 200 OK in 8ms (Views: 0.9ms | ActiveRecord: 1.0ms)
You can see the parameter data in the log. The controller action is pretty simple:
# PATCH/PUT /affiliates/1
def update
if #affiliate.update(affiliate_params)
render json: #affiliate
else
render json: #affiliate.errors, status: :unprocessable_entity
end
end
Thanks in advance for any help.

Answer 1

As it turns out, for whatever reason, the put method required me to identify the content type in the header. Post wasn't doing this, but changing the line in my HttParty call fixed the issue:
response = HTTParty.put(put_uri, body: #this_data.to_json, headers: { 'Content-Type' => 'application/json', 'Authorization' => #token })