From e23da802c29314c272250d9a37e3dc5f439c6398 Mon Sep 17 00:00:00 2001
From: Michael Vogt <mvo@ubuntu.com>
Date: Fri, 13 Oct 2023 11:51:23 +0200
Subject: [PATCH 1/2] google: mark cache as ready after it got populated

The googleImagesCache is currently not marked `ready` AFAICT.
This means while it is correctly build it is not used in
subsequent calls to projectImages(). This commit set the
cache to ready after it got populated.
---
 spread/google.go | 1 +
 1 file changed, 1 insertion(+)

diff --git a/spread/google.go b/spread/google.go
index d1b08a5b..fe6633f9 100644
--- a/spread/google.go
+++ b/spread/google.go
@@ -369,6 +369,7 @@ func (p *googleProvider) projectImages(project string) ([]googleImage, error) {
 			Terms:   toTerms(item.Description),
 		})
 	}
+	cache.ready = true
 
 	return cache.images, err
 }

From 0b21f7394b600cc91abe2b62db52578d6115f6a9 Mon Sep 17 00:00:00 2001
From: Michael Vogt <mvo@ubuntu.com>
Date: Fri, 13 Oct 2023 12:14:46 +0200
Subject: [PATCH 2/2] google: add test if image cache works

---
 spread/export_test.go | 17 +++++++++++
 spread/google.go      |  6 +++-
 spread/google_test.go | 69 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 91 insertions(+), 1 deletion(-)
 create mode 100644 spread/google_test.go

diff --git a/spread/export_test.go b/spread/export_test.go
index d20b407b..c27fca27 100644
--- a/spread/export_test.go
+++ b/spread/export_test.go
@@ -1,6 +1,7 @@
 package spread
 
 import (
+	"net/http"
 	"time"
 
 	"golang.org/x/crypto/ssh"
@@ -38,3 +39,19 @@ func MockSshDial(f func(network, addr string, config *ssh.ClientConfig) (*ssh.Cl
 }
 
 var QemuCmd = qemuCmd
+
+func NewGoogleProviderForTesting(mockApiURL string, p *Project, b *Backend, o *Options) *googleProvider {
+	provider := Google(p, b, o)
+	ggl := provider.(*googleProvider)
+	ggl.apiURL = mockApiURL
+	ggl.keyChecked = true
+	ggl.client = &http.Client{}
+
+	return ggl
+}
+
+func (p *googleProvider) ProjectImages(project string) ([]googleImage, error) {
+	return p.projectImages(project)
+}
+
+type GoogleImage = googleImage
diff --git a/spread/google.go b/spread/google.go
index fe6633f9..9e82835c 100644
--- a/spread/google.go
+++ b/spread/google.go
@@ -31,6 +31,8 @@ func Google(p *Project, b *Backend, o *Options) Provider {
 		options: o,
 
 		imagesCache: make(map[string]*googleImagesCache),
+
+		apiURL: "https://www.googleapis.com",
 	}
 }
 
@@ -50,6 +52,8 @@ type googleProvider struct {
 	keyErr     error
 
 	imagesCache map[string]*googleImagesCache
+
+	apiURL string
 }
 
 type googleServer struct {
@@ -899,7 +903,7 @@ func (p *googleProvider) dofl(method, subpath string, params interface{}, result
 
 	<-googleThrottle
 
-	url := "https://www.googleapis.com"
+	url := p.apiURL
 	if flags&noPathPrefix == 0 {
 		url += "/compute/v1/projects/" + p.gproject() + subpath
 	} else {
diff --git a/spread/google_test.go b/spread/google_test.go
new file mode 100644
index 00000000..6e5c839d
--- /dev/null
+++ b/spread/google_test.go
@@ -0,0 +1,69 @@
+package spread_test
+
+import (
+	"net/http"
+	"net/http/httptest"
+
+	"github.com/snapcore/spread/spread"
+
+	. "gopkg.in/check.v1"
+)
+
+type googleSuite struct{}
+
+var _ = Suite(&googleSuite{})
+
+func (s *googleSuite) TestImagesCache(c *C) {
+	n := 0
+	mockServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		switch n {
+		case 0:
+			c.Check(r.URL.Path, Equals, "/compute/v1/projects/snapd/global/images")
+			w.Write([]byte(`
+                {
+                    "items": [{"status":"READY","name":"ubuntu-1910-64-v20190826", "description":"ubuntu-19.10-64"}, {"status":"READY","name":"ubuntu-1904-64-v20190726", "description":"ubuntu-19.04-64"}]
+                }
+                `))
+		case 1:
+			c.Check(r.URL.Path, Equals, "/compute/v1/projects/other-project/global/images")
+			w.Write([]byte(`
+                {
+                    "items": [{"status":"READY","name":"ubuntu-2004-64-v20190826", "description":"ubuntu-19.10-64"}]
+                }
+                `))
+		default:
+			c.Fatalf("unexpected number of requests")
+		}
+		n++
+	}))
+	defer mockServer.Close()
+
+	g := spread.NewGoogleProviderForTesting(mockServer.URL, nil, nil, nil)
+	c.Assert(g, NotNil)
+
+	// Request the project images
+	images, err := g.ProjectImages("snapd")
+	c.Assert(err, IsNil)
+	c.Assert(images, HasLen, 2)
+	c.Check(images, DeepEquals, []spread.GoogleImage{
+		{"snapd", "ubuntu-1910-64-v20190826", "", []string{"ubuntu", "19.10", "64"}},
+		{"snapd", "ubuntu-1904-64-v20190726", "", []string{"ubuntu", "19.04", "64"}},
+	})
+	c.Check(n, Equals, 1)
+
+	// do it again, now it comes from the cache
+	images, err = g.ProjectImages("snapd")
+	c.Assert(err, IsNil)
+	c.Assert(images, HasLen, 2)
+	c.Check(images, DeepEquals, []spread.GoogleImage{
+		{"snapd", "ubuntu-1910-64-v20190826", "", []string{"ubuntu", "19.10", "64"}},
+		{"snapd", "ubuntu-1904-64-v20190726", "", []string{"ubuntu", "19.04", "64"}},
+	})
+	c.Check(n, Equals, 1)
+
+	// again, this time for another project
+	images, err = g.ProjectImages("other-project")
+	c.Assert(err, IsNil)
+	c.Assert(images, HasLen, 1)
+	c.Check(n, Equals, 2)
+}