update to use whosonfirst/go-cache v0.5.0; add tests

blob.go

@@ -1,13 +1,13 @@
-package cache
+package blob
 
 import (
 	"bufio"
 	"bytes"
 	"context"
 	wof_cache "github.com/whosonfirst/go-cache"
+	"github.com/whosonfirst/go-ioutil"
 	"gocloud.dev/blob"
 	"io"
-	"io/ioutil"
 	"sync/atomic"
 )
 
@@ -57,7 +57,7 @@ func (c *BlobCache) Name() string {
 	return "blob"
 }
 
-func (c *BlobCache) Get(ctx context.Context, key string) (io.ReadCloser, error) {
+func (c *BlobCache) Get(ctx context.Context, key string) (io.ReadSeekCloser, error) {
 
 	fh, err := c.bucket.NewReader(ctx, key, nil)
 
@@ -67,10 +67,10 @@ func (c *BlobCache) Get(ctx context.Context, key string) (io.ReadCloser, error)
 	}
 
 	atomic.AddInt64(&c.hits, 1)
-	return fh, nil
+	return ioutil.NewReadSeekCloser(fh)
 }
 
-func (c *BlobCache) Set(ctx context.Context, key string, fh io.ReadCloser) (io.ReadCloser, error) {
+func (c *BlobCache) Set(ctx context.Context, key string, fh io.ReadSeekCloser) (io.ReadSeekCloser, error) {
 
 	var wr_opts *blob.WriterOptions
 
@@ -79,7 +79,7 @@ func (c *BlobCache) Set(ctx context.Context, key string, fh io.ReadCloser) (io.R
 	if v != nil {
 		wr_opts = v.(*blob.WriterOptions)
 	}
-	
+
 	bucket_wr, err := c.bucket.NewWriter(ctx, key, wr_opts)
 
 	if err != nil {
@@ -114,7 +114,7 @@ func (c *BlobCache) Set(ctx context.Context, key string, fh io.ReadCloser) (io.R
 	atomic.AddInt64(&c.sets, 1)
 
 	r.Reset(b.Bytes())
-	return ioutil.NopCloser(r), nil
+	return ioutil.NewReadSeekCloser(r)
 }
 
 func (c *BlobCache) Unset(ctx context.Context, key string) error {

blob_test.go

@@ -0,0 +1,28 @@
+package blob
+
+import (
+	"context"
+	"github.com/whosonfirst/go-cache"
+	_ "gocloud.dev/blob/memblob"
+	"testing"
+)
+
+func TestFSCache(t *testing.T) {
+
+	ctx := context.Background()
+
+	c, err := cache.NewCache(ctx, "mem://")
+
+	if err != nil {
+		t.Fatalf("Failed to create mem:// cache, %v", err)
+	}
+
+	opts := &testCacheOptions{}
+
+	// This is defined in testing.go
+	err = testCache(ctx, c, opts)
+
+	if err != nil {
+		t.Fatalf("Cache tests failed, %v", err)
+	}
+}

doc.go

@@ -0,0 +1,2 @@
+// package blob implements the Who's On First `go-cache` interface using Google's GoCloud `Blob` objects.
+package blob

go.mod

@@ -3,6 +3,7 @@ module github.com/whosonfirst/go-cache-blob
 go 1.16
 
 require (
-	github.com/whosonfirst/go-cache v0.3.0
+	github.com/whosonfirst/go-cache v0.5.0
+	github.com/whosonfirst/go-ioutil v1.0.0
 	gocloud.dev v0.23.0
 )

go.sum

@@ -308,6 +308,10 @@ github.com/whosonfirst/go-cache v0.1.0 h1:w6o4pWT/q2q/uclV72EU3D9CCKOgU+w+D+GKpa
 github.com/whosonfirst/go-cache v0.1.0/go.mod h1:M5Iche+26mVKFph49/pxS5W4ULZ9Dr01mebPqswG8QU=
 github.com/whosonfirst/go-cache v0.3.0 h1:QwboIxWu3Ab2gPikTMAJT2kukRr5c5yr/+yoMFRo8vQ=
 github.com/whosonfirst/go-cache v0.3.0/go.mod h1:uYn6IpxBxuSdULs15zkHHkOHTW8i4AS4A3jTv8wcbGg=
+github.com/whosonfirst/go-cache v0.5.0 h1:s8o2FafYxI1TGJGqwi3G0XVD5yY1dvzwSe9dE5C+KfA=
+github.com/whosonfirst/go-cache v0.5.0/go.mod h1:YawO5K9kQa3XnrtdfwZ6OS4gwuO87S06FqIPblMqZf4=
+github.com/whosonfirst/go-ioutil v1.0.0 h1:sYpgJx7Wsp76e7PFGa8KKQBvWQW3+HMCWSJbKdD5m14=
+github.com/whosonfirst/go-ioutil v1.0.0/go.mod h1:2dS1vWdAIkiHDvDF8fYyjv6k2NISmwaIjJJeEDBEdvg=
 github.com/whosonfirst/go-whosonfirst-cache v0.1.0 h1:ryWTsHj7gAEjwHC/WjsjROpFflsz3SCa7W9Qnk4EU7k=
 github.com/whosonfirst/go-whosonfirst-cache v0.1.0/go.mod h1:P5Tx34j2M50qX/kTfXY516apwGzJGkFSBYQI7TGArKw=
 github.com/yuin/goldmark v1.1.25/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=

testing.go

@@ -0,0 +1,110 @@
+package blob
+
+// Eventually this will be deprecated and all of these methods will be publicly
+// available in go-cache/testing.go
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"github.com/whosonfirst/go-cache"
+	"io"
+	_ "log"
+)
+
+type testCacheOptions struct {
+	AllowCacheMiss bool
+}
+
+func testCache(ctx context.Context, c cache.Cache, opts *testCacheOptions) error {
+
+	k := "test"
+	v := "test"
+
+	fh1, err := cache.ReadSeekCloserFromString(v)
+
+	if err != nil {
+		return fmt.Errorf("Failed to create ReadSeekCloser, %v", err)
+	}
+
+	fh2, err := c.Set(ctx, k, fh1)
+
+	if err != nil {
+		return fmt.Errorf("Failed to set %s (%s), %v", k, v, err)
+	}
+
+	equals, err := compareReadSeekClosers(fh1, fh2)
+
+	if err != nil {
+		return fmt.Errorf("Failed to compare filehandles, %v", err)
+	}
+
+	if !equals {
+		return fmt.Errorf("Filehandles 1 and 2 failed equality test")
+	}
+
+	fh3, err := c.Get(ctx, k)
+
+	if err != nil && !cache.IsCacheMiss(err) {
+		return fmt.Errorf("Failed to get cache value for '%s', %v", k, err)
+	}
+
+	if err != nil {
+
+		if !opts.AllowCacheMiss {
+			return fmt.Errorf("Unexpected cache miss for '%s'", k)
+		}
+
+	} else {
+
+		equals, err = compareReadSeekClosers(fh1, fh3)
+
+		if err != nil {
+			return fmt.Errorf("Failed to compare filehandles 1 and 3, %v", err)
+		}
+
+		if !equals {
+			return fmt.Errorf("Filehandles 1 and 3 failed equality test")
+		}
+	}
+
+	return nil
+}
+
+func compareReadSeekClosers(fh1 io.ReadSeekCloser, fh2 io.ReadSeekCloser) (bool, error) {
+
+	fh1.Seek(0, 0)
+	fh2.Seek(0, 0)
+
+	defer func() {
+		fh1.Seek(0, 0)
+		fh2.Seek(0, 0)
+	}()
+
+	b1, err := io.ReadAll(fh1)
+
+	if err != nil {
+		return false, fmt.Errorf("Failed to read fh1, %v", err)
+	}
+
+	fh1.Seek(0, 0)
+
+	b2, err := io.ReadAll(fh2)
+
+	if err != nil {
+		return false, fmt.Errorf("Failed to read fh2, %v", err)
+	}
+
+	fh2.Seek(0, 0)
+
+	// log.Printf("1 '%s'\n", string(b1))
+	// log.Printf("2 '%s'\n", string(b2))
+
+	equals := bytes.Compare(b1, b2)
+
+	if equals != 0 {
+		return false, nil
+	}
+
+	return true, nil
+}