[do not merge] Feat/support batch read ops

aws-v1/client/client.go

@@ -653,6 +653,73 @@ func (fd *Client) TransactWriteItemsWithContext(ctx aws.Context, input *dynamodb
 	return fd.TransactWriteItems(input)
 }
 
+// BatchGetItem mock response for dynamodb
+func (fd *Client) BatchGetItem(input *dynamodb.BatchGetItemInput) (*dynamodb.BatchGetItemOutput, error) {
+	if fd.forceFailureErr != nil {
+		return nil, fd.forceFailureErr
+	}
+
+	responses := make(map[string][]map[string]*dynamodb.AttributeValue, len(input.RequestItems))
+	unprocessed := make(map[string]*dynamodb.KeysAndAttributes, len(input.RequestItems))
+
+	for tableName, reqs := range input.RequestItems {
+		unprocessedKeys := make([]map[string]*dynamodb.AttributeValue, 0, len(reqs.Keys))
+		responses[tableName] = make([]map[string]*dynamodb.AttributeValue, 0, len(reqs.Keys))
+
+		for _, req := range reqs.Keys {
+			getInput := &dynamodb.GetItemInput{
+				TableName:                aws.String(tableName),
+				Key:                      req,
+				ConsistentRead:           reqs.ConsistentRead,
+				AttributesToGet:          reqs.AttributesToGet,
+				ExpressionAttributeNames: reqs.ExpressionAttributeNames,
+				ProjectionExpression:     reqs.ProjectionExpression,
+			}
+
+			item, err := executeGetRequest(fd, getInput)
+			if err != nil {
+				unprocessedKeys = append(unprocessedKeys, req)
+
+				continue
+			}
+
+			responses[tableName] = append(responses[tableName], item)
+		}
+
+		if len(unprocessedKeys) > 0 {
+			unprocessed[tableName] = reqs
+
+			tableUnprocessedKeys := unprocessed[tableName]
+			tableUnprocessedKeys.Keys = unprocessedKeys
+
+			unprocessed[tableName] = tableUnprocessedKeys
+		}
+	}
+
+	return &dynamodb.BatchGetItemOutput{
+		Responses:       responses,
+		UnprocessedKeys: unprocessed,
+	}, nil
+}
+
+// BatchGetItemWithContext mock response for dynamodb
+func (fd *Client) BatchGetItemWithContext(ctx aws.Context, input *dynamodb.BatchGetItemInput, opts ...request.Option) (*dynamodb.BatchGetItemOutput, error) {
+	return fd.BatchGetItem(input)
+}
+
+func executeGetRequest(fd *Client, getInput *dynamodb.GetItemInput) (map[string]*dynamodb.AttributeValue, error) {
+	response, err := fd.GetItem(getInput)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(response.Item) == 0 {
+		return nil, ErrResourceNotFoundException
+	}
+
+	return response.Item, nil
+}
+
 func (fd *Client) getTable(tableName string) (*core.Table, error) {
 	table, ok := fd.tables[tableName]
 	if !ok {

aws-v1/client/client_test.go

@@ -1856,6 +1856,82 @@ func TestBatchWriteItemWithFailingDatabase(t *testing.T) {
 	c.NotEmpty(output.UnprocessedItems)
 }
 
+func TestBatchGetItemWithContext(t *testing.T) {
+	c := require.New(t)
+	client := setupClient(tableName)
+
+	err := ensurePokemonTable(client)
+	c.NoError(err)
+
+	item, err := dynamodbattribute.MarshalMap(pokemon{
+		ID:   "001",
+		Type: "grass",
+		Name: "Bulbasaur",
+	})
+	c.NoError(err)
+
+	input := &dynamodb.PutItemInput{
+		Item:      item,
+		TableName: aws.String(tableName),
+	}
+
+	_, err = client.PutItemWithContext(context.Background(), input)
+	c.NoError(err)
+
+	item, err = dynamodbattribute.MarshalMap(pokemon{
+		ID:   "002",
+		Type: "fire",
+		Name: "Charmander",
+	})
+	c.NoError(err)
+
+	input = &dynamodb.PutItemInput{
+		Item:      item,
+		TableName: aws.String(tableName),
+	}
+
+	_, err = client.PutItemWithContext(context.Background(), input)
+	c.NoError(err)
+
+	getInput := &dynamodb.BatchGetItemInput{
+		RequestItems: map[string]*dynamodb.KeysAndAttributes{
+			tableName: {
+				Keys: []map[string]*dynamodb.AttributeValue{
+					{
+						"id": {S: aws.String("001")},
+					},
+					{
+						"id": {S: aws.String("002")},
+					},
+					{
+						"t1": {S: aws.String("003")},
+					},
+					{
+						"id": {S: aws.String("004")},
+					},
+				},
+			},
+		},
+	}
+
+	ActiveForceFailure(client)
+
+	out, err := client.BatchGetItemWithContext(context.Background(), getInput)
+	c.Nil(out)
+	c.EqualError(err, ErrForcedFailure.Error())
+
+	DeactiveForceFailure(client)
+
+	out, err = client.BatchGetItemWithContext(context.Background(), getInput)
+	c.NoError(err)
+	c.Len(out.Responses[tableName], 2)
+	c.Equal("001", aws.StringValue(out.Responses[tableName][0]["id"].S))
+	c.Equal("002", aws.StringValue(out.Responses[tableName][1]["id"].S))
+	c.Len(out.UnprocessedKeys[tableName].Keys, 2)
+	c.Equal("003", aws.StringValue(out.UnprocessedKeys[tableName].Keys[0]["t1"].S))
+	c.Equal("004", aws.StringValue(out.UnprocessedKeys[tableName].Keys[1]["id"].S))
+}
+
 func TestTransactWriteItemsWithContext(t *testing.T) {
 	c := require.New(t)
 	client := NewClient()