GT-214 Implement checksum endpoint for collections (#446)

Author: jwierzbo

.gitignore

@@ -13,3 +13,6 @@ vendor
 # Helper files
 debug/
 *.log
+
+# direnv files
+.envrc

CHANGELOG.md

@@ -1,6 +1,7 @@
 # Change Log
 
 ## [master](https://github.com/arangodb/go-driver/tree/master) (N/A)
+- Add support for `checksum` in Collections
 
 ## [1.4.0](https://github.com/arangodb/go-driver/tree/v1.4.0) (2022-10-04)
 - Add `hex` property to analyzer's properties

collection.go

@@ -50,6 +50,11 @@ type Collection interface {
 	// in a collection has changed since the last revision check.
 	Revision(ctx context.Context) (string, error)
 
+	// Checksum returns a checksum for the specified collection
+	// withRevisions - Whether to include document revision ids in the checksum calculation.
+	// withData - Whether to include document body data in the checksum calculation.
+	Checksum(ctx context.Context, withRevisions bool, withData bool) (CollectionChecksum, error)
+
 	// Properties fetches extended information about the collection.
 	Properties(ctx context.Context) (CollectionProperties, error)
 
@@ -79,6 +84,14 @@ type Collection interface {
 	CollectionDocuments
 }
 
+// CollectionChecksum contains information about a collection checksum response
+type CollectionChecksum struct {
+	ArangoError
+	CollectionInfo
+	// The collection revision id as a string.
+	Revision string `json:"revision,omitempty"`
+}
+
 // CollectionInfo contains information about a collection
 type CollectionInfo struct {
 	// The identifier of the collection.
@@ -95,6 +108,8 @@ type CollectionInfo struct {
 	IsSystem bool `json:"isSystem,omitempty"`
 	// Global unique name for the collection
 	GloballyUniqueId string `json:"globallyUniqueId,omitempty"`
+	// The calculated checksum as a number.
+	Checksum string `json:"checksum,omitempty"`
 }
 
 // CollectionProperties contains extended information about a collection.
@@ -154,11 +169,11 @@ type CollectionProperties struct {
 	// The following attribute specifies if the new MerkleTree based sync protocol
 	// can be used on the collection.
 	SyncByRevision bool `json:"syncByRevision,omitempty"`
+	// The collection revision id as a string.
+	Revision string `json:"revision,omitempty"`
 	// Schema for collection validation
 	Schema *CollectionSchemaOptions `json:"schema,omitempty"`
 
-	Revision string `json:"revision,omitempty"`
-
 	// IsDisjoint set isDisjoint flag for Graph. Required ArangoDB 3.7+
 	IsDisjoint bool `json:"isDisjoint,omitempty"`
 

collection_impl.go

@@ -150,6 +150,37 @@ func (c *collection) Revision(ctx context.Context) (string, error) {
 	return data.Revision, nil
 }
 
+// Checksum returns a checksum for the specified collection
+// withRevisions - Whether to include document revision ids in the checksum calculation.
+// withData - Whether to include document body data in the checksum calculation.
+func (c *collection) Checksum(ctx context.Context, withRevisions bool, withData bool) (CollectionChecksum, error) {
+	var data CollectionChecksum
+
+	req, err := c.conn.NewRequest("GET", path.Join(c.relPath("collection"), "checksum"))
+	if err != nil {
+		return data, WithStack(err)
+	}
+	if withRevisions {
+		req.SetQuery("withRevisions", "true")
+	}
+	if withData {
+		req.SetQuery("withData", "true")
+	}
+
+	resp, err := c.conn.Do(ctx, req)
+	if err != nil {
+		return data, WithStack(err)
+	}
+	if err := resp.CheckStatus(200); err != nil {
+		return data, WithStack(err)
+	}
+
+	if err := resp.ParseBody("", &data); err != nil {
+		return data, WithStack(err)
+	}
+	return data, nil
+}
+
 // Properties fetches extended information about the collection.
 func (c *collection) Properties(ctx context.Context) (CollectionProperties, error) {
 	req, err := c.conn.NewRequest("GET", path.Join(c.relPath("collection"), "properties"))

edge_collection_impl.go

@@ -81,6 +81,15 @@ func (c *edgeCollection) Status(ctx context.Context) (CollectionStatus, error) {
 	return result, nil
 }
 
+// Checksum returns a checksum for the specified collection
+func (c *edgeCollection) Checksum(ctx context.Context, withRevisions bool, withData bool) (CollectionChecksum, error) {
+	result, err := c.rawCollection().Checksum(ctx, withRevisions, withData)
+	if err != nil {
+		return CollectionChecksum{}, WithStack(err)
+	}
+	return result, nil
+}
+
 // Count fetches the number of document in the collection.
 func (c *edgeCollection) Count(ctx context.Context) (int64, error) {
 	result, err := c.rawCollection().Count(ctx)

test/collection_test.go

@@ -761,6 +761,40 @@ func TestCollectionRevision(t *testing.T) {
 	}
 }
 
+// TestCollectionChecksum creates a collection, checks checksum after adding documents.
+func TestCollectionChecksum(t *testing.T) {
+	c := createClientFromEnv(t, true)
+	db := ensureDatabase(nil, c, "collection_checksum", nil, t)
+	name := "test_collection_checksum"
+	col, err := db.CreateCollection(nil, name, nil)
+	require.NoError(t, err)
+
+	// create some documents
+	for i := 0; i < 5; i++ {
+		before, err := col.Checksum(nil, false, false)
+		require.NoError(t, err)
+
+		doc := Book{Title: fmt.Sprintf("Book %d", i)}
+		_, err = col.CreateDocument(nil, doc)
+		require.NoError(t, err)
+
+		after, err := col.Checksum(nil, false, false)
+		require.NoError(t, err)
+		require.NotEqual(t, before.Checksum, after.Checksum)
+
+		afterWithRevision, err := col.Checksum(nil, true, false)
+		require.NoError(t, err)
+		require.NotEqual(t, before.Checksum, afterWithRevision.Checksum)
+		require.NotEqual(t, after.Checksum, afterWithRevision.Checksum)
+
+		afterWithData, err := col.Checksum(nil, false, true)
+		require.NoError(t, err)
+		require.NotEqual(t, before.Checksum, afterWithData.Checksum)
+		require.NotEqual(t, after.Checksum, afterWithData.Checksum)
+		require.NotEqual(t, afterWithRevision.Checksum, afterWithData.Checksum)
+	}
+}
+
 // TestCollectionStatistics creates a collection, checks statistics after adding documents.
 func TestCollectionStatistics(t *testing.T) {
 	c := createClientFromEnv(t, true)

vertex_collection_impl.go

@@ -81,6 +81,15 @@ func (c *vertexCollection) Status(ctx context.Context) (CollectionStatus, error)
 	return result, nil
 }
 
+// Checksum returns a checksum for the specified collection
+func (c *vertexCollection) Checksum(ctx context.Context, withRevisions bool, withData bool) (CollectionChecksum, error) {
+	result, err := c.rawCollection().Checksum(ctx, withRevisions, withData)
+	if err != nil {
+		return CollectionChecksum{}, WithStack(err)
+	}
+	return result, nil
+}
+
 // Count fetches the number of document in the collection.
 func (c *vertexCollection) Count(ctx context.Context) (int64, error) {
 	result, err := c.rawCollection().Count(ctx)