Fix travis build problems (#380)

* Run precompiling assets against test db.

* Fix failing tests because date after 2020-02-02.

* Use a data type postgres understands.

* Compile assets for tests to same directory.

* Swap the actual database config against one that builds against sqlite in production.

* Do not force install of sqlite as it is a dependency for all environments anyway.

* Add comments

* Run deployment from dev instead of this branch.

Author: WorldofJARcraft

Dockerfile

@@ -23,8 +23,17 @@ RUN bundle install --without development test
 
 COPY . .
 RUN yarn install --check-files
-
+# We need a database to precompile the assets. Compiling at run time is impossible; node fails because there is not enough memory.
+# Obviously, we do not want to connect to the real production database from whatever build server we run on.
+# So we exchange the real databas econfiguration that points to the Heroku database with one that points to a SQLite database we can quickly create on ephemeral storage.
+RUN cp ./config/database.yml ./config/database_real.yml
+RUN cp ./config/database_travis_build.yml ./config/database.yml
+# db schema needs to be created, so run migrations first
+RUN ./bin/rails db:migrate
+# now assets can be compiled
 RUN ./bin/rails assets:precompile
+# revert the change so we speak to the production database later
+RUN cp ./config/database_real.yml ./config/database.yml
 EXPOSE 3000
 ENV RAILS_SERVE_STATIC_FILES=true
 ENV RAILS_LOG_TO_STDOUT=true

config/database_travis_build.yml

@@ -0,0 +1,26 @@
+# SQLite version 3.x
+#   gem install sqlite3
+#
+#   Ensure the SQLite 3 gem is defined in your Gemfile
+#   gem 'sqlite3'
+#
+default: &default
+  adapter: sqlite3
+  pool: 5
+  timeout: 5000
+
+development:
+  <<: *default
+  database: db/development.sqlite3
+
+# Warning: The database defined as "test" will be erased and
+# re-generated from your development database when you run "rake".
+# Do not set this db to the same as development or production.
+test:
+  <<: *default
+  database: db/test.sqlite3
+
+#this config is used in deployment. To compile production assets, we need a database. We can not use PostGres since this build runs on a Travis machine, so use sqlite in this case.
+production:
+  <<: *default
+  database: db/test.sqlite3

db/migrate/20200129225856_add_index_to_poll_options.rb

@@ -1,5 +1,5 @@
 class AddIndexToPollOptions < ActiveRecord::Migration[5.2]
   def change
-    add_column :poll_options, :index, :number
+    add_column :poll_options, :index, :integer
   end
 end

spec/controllers/lectures_controller_spec.rb

@@ -3,7 +3,7 @@
 
 RSpec.describe LecturesController, type: :controller do
   let(:valid_attributes) {
-    { name: "SWT", enrollment_key: "swt", status: "created", date: "2020-02-02", start_time: "2020-01-01 10:10:00", end_time: "2020-01-01 10:20:00", questions_enabled: true, polls_enabled: true }
+    { name: "SWT", enrollment_key: "swt", status: "created", date: Date.tomorrow, start_time: "2020-01-01 10:10:00", end_time: "2020-01-01 10:20:00", questions_enabled: true, polls_enabled: true }
   }
   let(:valid_attributes_with_lecturer) {
     valid_attributes.merge(lecturer: FactoryBot.create(:user, :lecturer, email: "test@test.de"))

spec/models/lecture_spec.rb

@@ -2,7 +2,7 @@
 
 RSpec.describe Lecture, type: :model do
   let(:valid_attributes) {
-    { name: "SWT", enrollment_key: "swt", status: "created", date: "2020-02-02", start_time: "2020-01-01 10:10:00", end_time: "2020-01-01 10:20:00", questions_enabled: true, polls_enabled: true }
+    { name: "SWT", enrollment_key: "swt", status: "created", date: Date.tomorrow, start_time: "2020-01-01 10:10:00", end_time: "2020-01-01 10:20:00", questions_enabled: true, polls_enabled: true }
   }
   let(:valid_attributes_with_lecturer) {
     valid_attributes.merge(lecturer: FactoryBot.create(:user, :lecturer, email: "test@test.de"))

spec/views/lectures/edit.html.erb_spec.rb

@@ -9,7 +9,7 @@
                                   status: "created",
                                   lecturer: FactoryBot.create(:user, :lecturer),
                                   course: @course,
-                                  date: "2020-02-02",
+                                  date: Date.tomorrow,
                                   start_time: "2020-01-01 10:10:00",
                                   end_time: "2020-01-01 10:20:00"
     ))