(POOLER-153) Add endpoint for resetting a pool

This commit adds a capability to vmpooler to reset a pool, deleting its ready and pending instances and replacing them with fresh ones. Without this change vmpooler does not offer a mechanism to reset a pool without also changing its template.

spec/integration/api/v1/poolreset.rb

@@ -0,0 +1,117 @@
+require 'spec_helper'
+require 'rack/test'
+
+describe Vmpooler::API::V1 do
+  include Rack::Test::Methods
+
+  def app()
+    Vmpooler::API
+  end
+
+  let(:config) {
+    {
+      config: {
+        'site_name' => 'test pooler',
+        'vm_lifetime_auth' => 2,
+        'experimental_features' => true
+      },
+      pools: [
+        {'name' => 'pool1', 'size' => 5, 'template' => 'templates/pool1', 'clone_target' => 'default_cluster'},
+        {'name' => 'pool2', 'size' => 10}
+      ],
+      statsd: { 'prefix' => 'stats_prefix'},
+      alias: { 'poolone' => 'pool1' },
+      pool_names: [ 'pool1', 'pool2', 'poolone' ]
+    }
+  }
+
+  describe '/poolreset' do
+    let(:prefix) { '/api/v1' }
+    let(:metrics) { Vmpooler::DummyStatsd.new }
+
+    let(:current_time) { Time.now }
+
+    before(:each) do
+      app.settings.set :config, config
+      app.settings.set :redis, redis
+      app.settings.set :metrics, metrics
+      app.settings.set :config, auth: false
+      create_token('abcdefghijklmnopqrstuvwxyz012345', 'jdoe', current_time)
+    end
+
+    describe 'POST /poolreset' do
+      it 'refreshes ready and pending instances from a pool' do
+        post "#{prefix}/poolreset", '{"pool1":"1"}'
+        expect_json(ok = true, http = 201)
+
+        expected = { ok: true }
+
+        expect(last_response.body).to eq(JSON.pretty_generate(expected))
+      end
+
+      it 'fails on nonexistent pools' do
+        post "#{prefix}/poolreset", '{"poolpoolpool":"1"}'
+        expect_json(ok = false, http = 400)
+      end
+
+      it 'resets multiple pools' do
+        post "#{prefix}/poolreset", '{"pool1":"1","pool2":"1"}'
+        expect_json(ok = true, http = 201)
+
+        expected = { ok: true }
+
+        expect(last_response.body).to eq(JSON.pretty_generate(expected))
+      end
+
+      it 'fails when not all pools exist' do
+        post "#{prefix}/poolreset", '{"pool1":"1","pool3":"1"}'
+        expect_json(ok = false, http = 400)
+
+        expected = {
+          ok: false,
+          bad_pools: ['pool3']
+        }
+
+        expect(last_response.body).to eq(JSON.pretty_generate(expected))
+      end
+
+      context 'with experimental features disabled' do
+        before(:each) do
+          config[:config]['experimental_features'] = false
+        end
+
+        it 'should return 405' do
+          post "#{prefix}/poolreset", '{"pool1":"1"}'
+          expect_json(ok = false, http = 405)
+
+          expected = { ok: false }
+          expect(last_response.body).to eq(JSON.pretty_generate(expected))
+        end
+      end
+
+      it 'should return 400 for invalid json' do
+        post "#{prefix}/poolreset", '{"pool1":"1}'
+        expect_json(ok = false, http = 400)
+
+        expected = { ok: false }
+        expect(last_response.body).to eq(JSON.pretty_generate(expected))
+      end
+
+      it 'should return 400 with a bad pool name' do
+        post "#{prefix}/poolreset", '{"pool11":"1"}'
+        expect_json(ok = false, http = 400)
+
+        expected = { ok: false }
+        expect(last_response.body).to eq(JSON.pretty_generate(expected))
+      end
+
+      it 'should return 404 when there is no payload' do
+        post "#{prefix}/poolreset"
+        expect_json(ok = false, http = 404)
+
+        expected = { ok: false }
+        expect(last_response.body).to eq(JSON.pretty_generate(expected))
+      end
+    end
+  end
+end

spec/unit/pool_manager_spec.rb

@@ -2874,6 +2874,28 @@ EOT
         end
       end
     end
+
+    describe 'with the pool_reset wakeup option' do
+      let(:wakeup_option) {{
+        :pool_reset => true,
+        :poolname => pool
+      }}
+
+      let(:wakeup_period) { -1 } # A negative number forces the wakeup evaluation to always occur
+
+      context 'when a pool reset is requested' do
+        before(:each) do
+          redis.sadd('vmpooler__poolreset', pool)
+        end
+
+        it 'should sleep until the reset request is detected' do
+          expect(subject).to receive(:sleep).exactly(3).times
+          expect(redis).to receive(:sismember).with('vmpooler__poolreset', pool).and_return(false,false,true)
+
+          subject.sleep_with_wakeup_events(loop_delay, wakeup_period, wakeup_option)
+        end
+      end
+    end
   end
 
   describe "#check_pool" do