Merge pull request #653 from pdevine/catalog-api

Catalog for V2 API Implementation

docs/storage/catalog.go

@@ -0,0 +1,65 @@
+package storage
+
+import (
+	"errors"
+	"io"
+	"path"
+	"sort"
+	"strings"
+
+	"github.com/docker/distribution/context"
+	"github.com/docker/distribution/registry/storage/driver"
+)
+
+// Returns a list, or partial list, of repositories in the registry.
+// Because it's a quite expensive operation, it should only be used when building up
+// an initial set of repositories.
+func (reg *registry) Repositories(ctx context.Context, repos []string, last string) (n int, err error) {
+	var foundRepos []string
+	var errVal error
+
+	if len(repos) == 0 {
+		return 0, errors.New("no space in slice")
+	}
+
+	root, err := defaultPathMapper.path(repositoriesRootPathSpec{})
+	if err != nil {
+		return 0, err
+	}
+
+	// Walk each of the directories in our storage.  Unfortunately since there's no
+	// guarantee that storage will return files in lexigraphical order, we have
+	// to store everything another slice, sort it and then copy it back to our
+	// passed in slice.
+
+	Walk(ctx, reg.blobStore.driver, root, func(fileInfo driver.FileInfo) error {
+		filePath := fileInfo.Path()
+
+		// lop the base path off
+		repoPath := filePath[len(root)+1:]
+
+		_, file := path.Split(repoPath)
+		if file == "_layers" {
+			repoPath = strings.TrimSuffix(repoPath, "/_layers")
+			if repoPath > last {
+				foundRepos = append(foundRepos, repoPath)
+			}
+			return ErrSkipDir
+		} else if strings.HasPrefix(file, "_") {
+			return ErrSkipDir
+		}
+
+		return nil
+	})
+
+	sort.Strings(foundRepos)
+	n = copy(repos, foundRepos)
+
+	// Signal that we have no more entries by setting EOF
+	if len(foundRepos) <= len(repos) {
+		errVal = io.EOF
+	}
+
+	return n, errVal
+
+}

docs/storage/catalog_test.go

@@ -0,0 +1,122 @@
+package storage
+
+import (
+	"io"
+	"testing"
+
+	"github.com/docker/distribution"
+	"github.com/docker/distribution/context"
+	"github.com/docker/distribution/registry/storage/cache/memory"
+	"github.com/docker/distribution/registry/storage/driver"
+	"github.com/docker/distribution/registry/storage/driver/inmemory"
+)
+
+type setupEnv struct {
+	ctx      context.Context
+	driver   driver.StorageDriver
+	expected []string
+	registry distribution.Namespace
+}
+
+func setupFS(t *testing.T) *setupEnv {
+	d := inmemory.New()
+	c := []byte("")
+	ctx := context.Background()
+	registry := NewRegistryWithDriver(ctx, d, memory.NewInMemoryBlobDescriptorCacheProvider())
+	rootpath, _ := defaultPathMapper.path(repositoriesRootPathSpec{})
+
+	repos := []string{
+		"/foo/a/_layers/1",
+		"/foo/b/_layers/2",
+		"/bar/c/_layers/3",
+		"/bar/d/_layers/4",
+		"/foo/d/in/_layers/5",
+		"/an/invalid/repo",
+		"/bar/d/_layers/ignored/dir/6",
+	}
+
+	for _, repo := range repos {
+		if err := d.PutContent(ctx, rootpath+repo, c); err != nil {
+			t.Fatalf("Unable to put to inmemory fs")
+		}
+	}
+
+	expected := []string{
+		"bar/c",
+		"bar/d",
+		"foo/a",
+		"foo/b",
+		"foo/d/in",
+	}
+
+	return &setupEnv{
+		ctx:      ctx,
+		driver:   d,
+		expected: expected,
+		registry: registry,
+	}
+}
+
+func TestCatalog(t *testing.T) {
+	env := setupFS(t)
+
+	p := make([]string, 50)
+
+	numFilled, err := env.registry.Repositories(env.ctx, p, "")
+
+	if !testEq(p, env.expected, numFilled) {
+		t.Errorf("Expected catalog repos err")
+	}
+
+	if err != io.EOF {
+		t.Errorf("Catalog has more values which we aren't expecting")
+	}
+}
+
+func TestCatalogInParts(t *testing.T) {
+	env := setupFS(t)
+
+	chunkLen := 2
+	p := make([]string, chunkLen)
+
+	numFilled, err := env.registry.Repositories(env.ctx, p, "")
+	if err == io.EOF || numFilled != len(p) {
+		t.Errorf("Expected more values in catalog")
+	}
+
+	if !testEq(p, env.expected[0:chunkLen], numFilled) {
+		t.Errorf("Expected catalog first chunk err")
+	}
+
+	lastRepo := p[len(p)-1]
+	numFilled, err = env.registry.Repositories(env.ctx, p, lastRepo)
+
+	if err == io.EOF || numFilled != len(p) {
+		t.Errorf("Expected more values in catalog")
+	}
+
+	if !testEq(p, env.expected[chunkLen:chunkLen*2], numFilled) {
+		t.Errorf("Expected catalog second chunk err")
+	}
+
+	lastRepo = p[len(p)-1]
+	numFilled, err = env.registry.Repositories(env.ctx, p, lastRepo)
+
+	if err != io.EOF {
+		t.Errorf("Catalog has more values which we aren't expecting")
+	}
+
+	if !testEq(p, env.expected[chunkLen*2:chunkLen*3-1], numFilled) {
+		t.Errorf("Expected catalog third chunk err")
+	}
+
+}
+
+func testEq(a, b []string, size int) bool {
+	for cnt := 0; cnt < size-1; cnt++ {
+		if a[cnt] != b[cnt] {
+			return false
+		}
+	}
+	return true
+}