ActionController::UnknownFormat in MeetingsController#update - ruby-on-rails

Question

I have read countless SO questions about this issue, and can not find a solution.
I have a button that updates Meeting here:
<%= form_for(meeting) do |f| %>
<%= f.hidden_field :accepted, value: true %>
<%= button_tag(type: 'submit', class: "btn_primary") do %>
Accept <svg><use xlink:href="#checkmark"/></svg>
<% end %>
<% end %>
I get an unknown format error, BUT it still updates. What is causing this error?
I have tried removing respond_to do |format| from the update method. which solves the problem for this one button, but then breaks all the other buttons on the platform that calls meetings/update.
class MeetingsController < ApplicationController
respond_to :json, :html
def update
respond_to do |format| **error highlights this line**
if #meeting.update(meeting_params)
format.json { render :show, status: :ok, location: #meeting }
else
format.html { render :edit }
format.json { render json: #meeting.errors, status: :unprocessable_entity }
end
end
end
end
Console:
Started PATCH "/meetings/224" for 127.0.0.1 at 2016-11-11 16:05:27 -0500
Processing by MeetingsController#update as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"hK6AoOZuw9DWyKUXw1dXWOSUolooWgBUPnkItUJX5Tm7XvimsHd9518pkqwVvNhUi3L3vlA4OZaJZiAgrbS0Ig==", "meeting"=>{"accepted"=>"true"}, "button"=>"", "id"=>"224"}
User Load (0.4ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? ORDER BY "users"."id" ASC LIMIT 1 [["id", 1]]
Meeting Load (0.2ms) SELECT "meetings".* FROM "meetings" WHERE "meetings"."id" = ? LIMIT 1 [["id", 224]]
(0.3ms) begin transaction
SQL (0.5ms) UPDATE "meetings" SET "accepted" = ?, "updated_at" = ? WHERE "meetings"."id" = ? [["accepted", "t"], ["updated_at", "2016-11-11 21:05:27.882521"], ["id", 224]]
(1.3ms) commit transaction
Completed 406 Not Acceptable in 24ms (ActiveRecord: 2.7ms)
ActionController::UnknownFormat (ActionController::UnknownFormat):
app/controllers/meetings_controller.rb:65:in `update'
This was never an issue, and seemingly came out of no where. What is the cause of this error? Thanks!

Answer 1

I think I know what the issue is. I've added a line to your update method
class MeetingsController < ApplicationController
respond_to :json, :html
def update
respond_to do |format| **error highlights this line**
if #meeting.update(meeting_params)
format.html { redirect_to some_rails_path }
format.json { render :show, status: :ok, location: #meeting }
else
format.html { render :edit }
format.json { render json: #meeting.errors, status: :unprocessable_entity }
end
end
end
end
The reason you're getting an unknown format error but still successfully updating meeting is because your method has solid logic, so it's updating the meeting, but then once it does that, and you're only telling it what to do in terms of JSON but not in terms of HTML, you address both in your else statement, but not if the update succeeds.

Answer 2

Is this supposed to be an ajax request? It doesn't seem to be. But you're rendering json instead of html. If you're going to allow the page to reload you need to add an html option to if #meeting.update(meeting_params)
Something like: format.html { redirect_to #meeting, notice: 'Meeting was successfully updated.' }
If you're doing an ajax request this isn't the correct answer, but I don't see any indication in your question that you are. Lmk if you need further clarification.