JSON::ParserError in CoursesController#index - html

Question

I am a beginner of Ruby on Rails and web development. I am taking a online course and keep failing the lecture example.
My problem is my courses_controller, index action.
Controller: my_first_app/controllers/courses_controller.rb
class CoursesController < ApplicationController
def index
#search_term = 'jhu'
#courses = Coursera.for(#search_term)
end
end
Model: my_first_app/models/coursera.rb
class Coursera
include HTTParty
#default_options.update(verify: false) # Turn off SSL verification
base_uri 'https://api.coursera.org/api/catalog.v1/courses'
default_params fields: "smallIcon,shortDescription", q: "search"
format :json
def self.for term
get("", query: { query: term})["elements"]
end
end
View: my_first_app/views/index.html.erb
<h1>Search for - <%= #search_term %> </h1>
<table border = "1">
<tr>
<th>Image</th>
<th>Name</th>
<th>Description</th>
</tr>
<%= #courses.each do |course| %>
<tr>
<td><%= image_tag(course["smallIcon"]) %></td>
<td><%= course["name"] %></td>
<td><%= course["shortDescription"] %> </td>
</tr>
<% end %>
Routes: my_first_app/config/routes.rb
Rails.application.routes.draw do
get 'courses/index'
get 'greeter/hello'
get 'greeter/goodbye'
end
Gemfile:
source 'https://rubygems.org'
gem 'rails', '4.2.3'
gem 'sqlite3'
gem 'sass-rails', '~> 5.0'
gem 'uglifier', '>= 1.3.0'
gem 'coffee-rails', '~> 4.1.0'
gem 'jquery-rails'
gem 'turbolinks'
gem 'jbuilder', '~> 2.0'
gem 'sdoc', '~> 0.4.0', group: :doc
group :development, :test do
gem 'byebug'
gem 'web-console', '~> 2.0'
gem 'spring'
gem 'httparty', '0.13.5'
end
I added the last gem to the Gemfile and run bundle, then I controlled +c to stopped and restarted the server and I got the error message:
JSON::ParserError in CoursesController#index
error message screenshot
I think it is saying that I parse a HTML instead of JSON, but I don't know how to fix it. Any help will be appreciated.
Original repository: https://github.com/jhu-ep-coursera/fullstack-course1-module3

Answer 1

According to the API documentation for Coursera, it looks like your base_uri might need to be:
base_uri 'https://api.coursera.org/api/courses.v1'
and then for fields in the default_params should (maybe) be:
default_params fields: "photoUrl,description", q: "search"
(changing the other occurrences of 'smallIcon' and 'shortDescription' with 'photoUrl' and 'description' in your app as well, since I don't see those fields in the api docs).
Once those changes are made you should end up going to urls like https://api.coursera.org/api/courses.v1?q=search&query=ruby&fields=photoUrl,description which is returning valid JSON. The current base_uri you are using is sending you to an HTML error page telling you Action not found. Since that's an HTML page, JSON can't parse it.
If you look at the date on the last commit in the Github repository you linked, the last commit was in November 2015, so nearly 2 years ago. Just super out of date, the API has probably changed a fair bit since then.