Automate the basic API tests in a QA scenario

Signed-off-by: Rémy Coutable <remy@rymai.me>

qa/qa/specs/features/api/basics_spec.rb

+require 'securerandom'
+
+module QA
+  feature 'API basics', :core do
+    before(:context) do
+      @api_client = Runtime::API::Client.new(:gitlab)
+    end
+
+    let(:project_name) { "api-basics-#{SecureRandom.hex(8)}" }
+    let(:sanitized_project_path) { CGI.escape("#{Runtime::User.name}/#{project_name}") }
+
+    scenario 'user creates a project with a file and deletes them afterwards' do
+      create_project_request = Runtime::API::Request.new(@api_client, '/projects')
+      post create_project_request.url, path: project_name, name: project_name
+
+      expect_status(201)
+      expect(json_body).to match(
+        a_hash_including(name: project_name, path: project_name)
+      )
+
+      create_file_request = Runtime::API::Request.new(@api_client, "/projects/#{sanitized_project_path}/repository/files/README.md")
+      post create_file_request.url, branch: 'master', content: 'Hello world', commit_message: 'Add README.md'
+
+      expect_status(201)
+      expect(json_body).to match(
+        a_hash_including(branch: 'master', file_path: 'README.md')
+      )
+
+      get_file_request = Runtime::API::Request.new(@api_client, "/projects/#{sanitized_project_path}/repository/files/README.md", ref: 'master')
+      get get_file_request.url
+
+      expect_status(200)
+      expect(json_body).to match(
+        a_hash_including(
+          ref: 'master',
+          file_path: 'README.md', file_name: 'README.md',
+          encoding: 'base64', content: 'SGVsbG8gd29ybGQ='
+        )
+      )
+
+      delete_file_request = Runtime::API::Request.new(@api_client, "/projects/#{sanitized_project_path}/repository/files/README.md", branch: 'master', commit_message: 'Remove README.md')
+      delete delete_file_request.url
+
+      expect_status(204)
+
+      get_tree_request = Runtime::API::Request.new(@api_client, "/projects/#{sanitized_project_path}/repository/tree")
+      get get_tree_request.url
+
+      expect_status(200)
+      expect(json_body).to eq([])
+
+      delete_project_request = Runtime::API::Request.new(@api_client, "/projects/#{sanitized_project_path}")
+      delete delete_project_request.url
+
+      expect_status(202)
+      expect(json_body).to match(
+        a_hash_including(message: '202 Accepted')
+      )
+    end
+  end
+end