speed up test runs by only booting docker once in a run block per test case

spec/simple_spec.rb

@@ -59,17 +59,19 @@ RSpec.describe "Simple" do
     let(:name) { "routes" }
 
     it "should support custom routes" do
-      response = app.get("/foo.html")
-      expect(response.code).to eq("200")
-      expect(response.body.chomp).to eq("hello world")
+      app.run do
+        response = app.get("/foo.html")
+        expect(response.code).to eq("200")
+        expect(response.body.chomp).to eq("hello world")
 
-      response = app.get("/route/foo")
-      expect(response.code).to eq("200")
-      expect(response.body.chomp).to eq("hello from route")
+        response = app.get("/route/foo")
+        expect(response.code).to eq("200")
+        expect(response.body.chomp).to eq("hello from route")
 
-      response = app.get("/route/foo/bar")
-      expect(response.code).to eq("200")
-      expect(response.body.chomp).to eq("hello from route")
+        response = app.get("/route/foo/bar")
+        expect(response.code).to eq("200")
+        expect(response.body.chomp).to eq("hello from route")
+      end
     end
   end
 
@@ -158,30 +160,34 @@ STATIC_JSON
     let(:name) { "custom_headers" }
 
     it "should return the respected headers only for the path specified" do
-      response = app.get("/")
-      expect(response["cache-control"]).to eq("no-cache")
-      expect(response.code).to eq("200")
-      expect(response.body.chomp).to eq("index")
+      app.run do
+        response = app.get("/")
+        expect(response["cache-control"]).to eq("no-cache")
+        expect(response.code).to eq("200")
+        expect(response.body.chomp).to eq("index")
 
-      response = app.get("/foo.html")
-      expect(response["cache-control"]).to eq(nil)
-      expect(response.code).to eq("200")
-      expect(response.body.chomp).to eq("foo")
+        response = app.get("/foo.html")
+        expect(response["cache-control"]).to eq(nil)
+        expect(response.code).to eq("200")
+        expect(response.body.chomp).to eq("foo")
+      end
     end
 
     describe "wildcard paths" do
       let(:name) { "custom_headers_wildcard" }
 
       it "should add the headers" do
-        response = app.get("/cache/")
-        expect(response["Cache-Control"]).to eq("max-age=38400")
-        expect(response.code).to eq("200")
-        expect(response.body.chomp).to eq("cached index")
-
-        response = app.get("/")
-        expect(response["Cache-Control"]).to eq(nil)
-        expect(response.code).to eq("200")
-        expect(response.body.chomp).to eq("index")
+        app.run do
+          response = app.get("/cache/")
+          expect(response["Cache-Control"]).to eq("max-age=38400")
+          expect(response.code).to eq("200")
+          expect(response.body.chomp).to eq("cached index")
+
+          response = app.get("/")
+          expect(response["Cache-Control"]).to eq(nil)
+          expect(response.code).to eq("200")
+          expect(response.body.chomp).to eq("index")
+        end
       end
     end
 
@@ -199,15 +205,17 @@ STATIC_JSON
       let(:name) { "custom_headers_clean_urls" }
 
       it "should add the headers" do
-        response = app.get("/foo")
-        expect(response.code).to eq("200")
-        expect(response.body.chomp).to eq("foo")
-        expect(response["X-Header"]).to eq("present")
-
-        response = app.get("/bar")
-        expect(response.code).to eq("200")
-        expect(response.body.chomp).to eq("bar")
-        expect(response["X-Header"]).to be_nil
+        app.run do
+          response = app.get("/foo")
+          expect(response.code).to eq("200")
+          expect(response.body.chomp).to eq("foo")
+          expect(response["X-Header"]).to eq("present")
+
+          response = app.get("/bar")
+          expect(response.code).to eq("200")
+          expect(response.body.chomp).to eq("bar")
+          expect(response["X-Header"]).to be_nil
+        end
       end
 
       it "should not add headers for .html urls" do
@@ -221,15 +229,17 @@ STATIC_JSON
       let(:name) { "custom_headers_routes" }
 
       it "should add headers" do
-        response = app.get("/active")
-        expect(response.code).to eq("200")
-        expect(response.body.chomp).to eq("index")
-        expect(response["X-Header"]).to eq("present")
-
-        response = app.get("/foo/foo.html")
-        expect(response.code).to eq("200")
-        expect(response.body.chomp).to eq("foo")
-        expect(response["X-Header"]).to be_nil
+        app.run do
+          response = app.get("/active")
+          expect(response.code).to eq("200")
+          expect(response.body.chomp).to eq("index")
+          expect(response["X-Header"]).to eq("present")
+
+          response = app.get("/foo/foo.html")
+          expect(response.code).to eq("200")
+          expect(response.body.chomp).to eq("foo")
+          expect(response["X-Header"]).to be_nil
+        end
       end
     end
 
@@ -269,15 +279,17 @@ STATIC_JSON
       end
 
       it "should proxy requests" do
-        response = app.get("/api/bar/")
-        expect(response.code).to eq("200")
-        expect(response.body.chomp).to eq("api")
-        expect(response["X-Header"]).to eq("present")
-
-        response = app.get("/api/baz/")
-        expect(response.code).to eq("200")
-        expect(response.body.chomp).to eq("baz")
-        expect(response["X-Header"]).to be_nil
+        app.run do
+          response = app.get("/api/bar/")
+          expect(response.code).to eq("200")
+          expect(response.body.chomp).to eq("api")
+          expect(response["X-Header"]).to eq("present")
+
+          response = app.get("/api/baz/")
+          expect(response.code).to eq("200")
+          expect(response.body.chomp).to eq("baz")
+          expect(response["X-Header"]).to be_nil
+        end
       end
     end
   end

spec/support/app_runner.rb

@@ -20,6 +20,7 @@ class AppRunner
   CONTAINER_PORT = "3000"
 
   def initialize(fixture, env = nil, debug = false)
+    @run       = false
     @debug     = debug
     @container = Docker::Container.create(
       'Image'      => BuildpackBuilder::TAG,
@@ -39,7 +40,9 @@ class AppRunner
   end
 
   def run
-    latch = Concurrent::CountDownLatch.new(1)
+    @run       = true
+    retn       = nil
+    latch      = Concurrent::CountDownLatch.new(1)
     run_thread = Thread.new {
       latch.wait(0.5)
       yield(@container)
@@ -51,26 +54,20 @@ class AppRunner
       end
     }
 
-    run_thread.join
+    retn = run_thread.value
     @container.stop
     container_thread.join
+    @run = false
+
+    retn
   end
 
   def get(path, max_retries = 5)
-    response = nil
-
-    run do
-      network_retry(max_retries) do
-        uri = URI("#{path}")
-        uri.host   = HOST_IP   if uri.host.nil?
-        uri.port   = HOST_PORT if (uri.host == HOST_IP && uri.port != HOST_PORT) || uri.port.nil?
-        uri.scheme = "http"    if uri.scheme.nil?
-
-        response = Net::HTTP.get_response(URI(uri.to_s))
-      end
+    if @run
+      response = get_retry(path, max_retries)
+    else
+      run { get_retry(path, max_retries) }
     end
-
-    response
   end
 
   def destroy
@@ -78,6 +75,17 @@ class AppRunner
   end
 
   private
+  def get_retry(path, max_retries)
+    network_retry(max_retries) do
+      uri = URI("#{path}")
+      uri.host   = HOST_IP   if uri.host.nil?
+      uri.port   = HOST_PORT if (uri.host == HOST_IP && uri.port != HOST_PORT) || uri.port.nil?
+      uri.scheme = "http"    if uri.scheme.nil?
+
+      Net::HTTP.get_response(URI(uri.to_s))
+    end
+  end
+
   def network_retry(max_retries, retry_count = 0)
     yield
   rescue Errno::ECONNRESET, EOFError