refactor scraper into modules

2 files changed, 77 insertions, 0 deletions

diff --git a/modules/depth/depth.go b/modules/depth/depth.go
new file mode 100644
index 0000000..5efedc8
--- /dev/null
+++ b/modules/depth/depth.go
@@ -0,0 +1,30 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package depth
+
+import (
+	"github.com/philippta/flyscrape"
+)
+
+func init() {
+	flyscrape.RegisterModule(new(Module))
+}
+
+type Module struct {
+	Depth int `json:"depth"`
+}
+
+func (m *Module) ID() string {
+	return "depth"
+}
+
+func (m *Module) CanRequest(url string, depth int) bool {
+	return depth <= m.Depth
+}
+
+var (
+	_ flyscrape.Module     = (*Module)(nil)
+	_ flyscrape.CanRequest = (*Module)(nil)
+)
diff --git a/modules/depth/depth_test.go b/modules/depth/depth_test.go
new file mode 100644
index 0000000..309e628
--- /dev/null
+++ b/modules/depth/depth_test.go
@@ -0,0 +1,47 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package depth_test
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/philippta/flyscrape"
+	"github.com/philippta/flyscrape/modules/depth"
+	"github.com/philippta/flyscrape/modules/followlinks"
+	"github.com/philippta/flyscrape/modules/starturl"
+	"github.com/stretchr/testify/require"
+)
+
+func TestDepth(t *testing.T) {
+	scraper := flyscrape.NewScraper()
+	scraper.LoadModule(&starturl.Module{URL: "http://www.example.com/"})
+	scraper.LoadModule(&followlinks.Module{})
+	scraper.LoadModule(&depth.Module{Depth: 2})
+
+	scraper.SetTransport(func(r *http.Request) (*http.Response, error) {
+		switch r.URL.String() {
+		case "http://www.example.com/":
+			return flyscrape.MockResponse(200, `<a href="http://www.google.com">Google</a>`)
+		case "http://www.google.com/":
+			return flyscrape.MockResponse(200, `<a href="http://www.duckduckgo.com">DuckDuckGo</a>`)
+		case "http://www.duckduckgo.com/":
+			return flyscrape.MockResponse(200, `<a href="http://www.example.com">Example</a>`)
+		}
+		return flyscrape.MockResponse(200, "")
+	})
+
+	var urls []string
+	scraper.OnRequest(func(req *flyscrape.Request) {
+		urls = append(urls, req.URL)
+	})
+
+	scraper.Run()
+
+	require.Len(t, urls, 3)
+	require.Contains(t, urls, "http://www.example.com/")
+	require.Contains(t, urls, "http://www.google.com/")
+	require.Contains(t, urls, "http://www.duckduckgo.com/")
+}