kadm: add DeleteTopic,DeleteGroup,Error

Adds Error for many responses, which may sometimes be helpful.

pkg/kadm/groups.go

@@ -162,6 +162,17 @@ func (rs DescribedGroups) On(group string, fn func(*DescribedGroup) error) (Desc
 	return DescribedGroup{}, kerr.GroupIDNotFound
 }
 
+// Error iterates over all groups and returns the first error encountered, if
+// any.
+func (ds DescribedGroups) Error() error {
+	for _, d := range ds {
+		if d.Err != nil {
+			return d.Err
+		}
+	}
+	return nil
+}
+
 // Topics returns a sorted list of all group names.
 func (ds DescribedGroups) Names() []string {
 	all := make([]string, 0, len(ds))
@@ -385,6 +396,32 @@ func (rs DeleteGroupResponses) On(group string, fn func(*DeleteGroupResponse) er
 	return DeleteGroupResponse{}, kerr.GroupIDNotFound
 }
 
+// Error iterates over all groups and returns the first error encountered, if
+// any.
+func (rs DeleteGroupResponses) Error() error {
+	for _, r := range rs {
+		if r.Err != nil {
+			return r.Err
+		}
+	}
+	return nil
+}
+
+// DeleteGroup deletes the specified group. This is similar to DeleteGroups,
+// but returns the kerr.ErrorForCode(response.ErrorCode) if the request/response
+// is successful.
+func (cl *Client) DeleteGroup(ctx context.Context, group string) (DeleteGroupResponse, error) {
+	rs, err := cl.DeleteGroups(ctx, group)
+	if err != nil {
+		return DeleteGroupResponse{}, err
+	}
+	g, exists := rs[group]
+	if !exists {
+		return DeleteGroupResponse{}, errors.New("requested group was not part of the delete group response")
+	}
+	return g, g.Err
+}
+
 // DeleteGroups deletes all groups specified.
 //
 // The purpose of this request is to allow operators a way to delete groups
@@ -984,6 +1021,17 @@ func (rs FetchOffsetsResponses) On(group string, fn func(*FetchOffsetsResponse)
 	return FetchOffsetsResponse{}, kerr.GroupIDNotFound
 }
 
+// Error iterates over all responses and returns the first error encountered,
+// if any.
+func (rs FetchOffsetsResponses) Error() error {
+	for _, r := range rs {
+		if r.Err != nil {
+			return r.Err
+		}
+	}
+	return nil
+}
+
 // FetchManyOffsets issues a fetch offsets requests for each group specified.
 //
 // This function is a batch version of FetchOffsets. FetchOffsets and
@@ -1092,6 +1140,19 @@ func (ds DeleteOffsetsResponses) EachError(fn func(string, int32, error)) {
 	}
 }
 
+// Error iterates over all responses and returns the first error encountered,
+// if any.
+func (ds DeleteOffsetsResponses) Error() error {
+	for _, ps := range ds {
+		for _, err := range ps {
+			if err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
 // DeleteOffsets deletes offsets for the given group.
 //
 // Originally, offset commits were persisted in Kafka for some retention time.

pkg/kadm/partas.go

@@ -69,6 +69,18 @@ func (rs AlterPartitionAssignmentsResponses) Each(fn func(AlterPartitionAssignme
 	}
 }
 
+// Error returns the first error in the responses, if any.
+func (rs AlterPartitionAssignmentsResponses) Error() error {
+	for _, ps := range rs {
+		for _, r := range ps {
+			if r.Err != nil {
+				return r.Err
+			}
+		}
+	}
+	return nil
+}
+
 // AlterPartitionAssignments alters partition assignments for the requested
 // partitions, returning an error if the response could not be issued or if
 // you do not have permissions.

pkg/kadm/topics.go

@@ -91,24 +91,21 @@ func (rs CreateTopicResponses) On(topic string, fn func(*CreateTopicResponse) er
 	return CreateTopicResponse{}, kerr.UnknownTopicOrPartition
 }
 
+// Error iterates over all responses and returns the first error
+// encountered, if any.
+func (rs CreateTopicResponses) Error() error {
+	for _, r := range rs {
+		if r.Err != nil {
+			return r.Err
+		}
+	}
+	return nil
+}
+
 // CreateTopic issues a create topics request with the given partitions,
-// replication factor, and (optional) configs for the given topic name. Under
-// the hood, this uses the default 15s request timeout and lets Kafka choose
-// where to place partitions. This function exists to complement CreateTopics,
-// making the single-topic creation case easier to handle.
-//
-// Version 4 of the underlying create topic request was introduced in Kafka 2.4
-// and brought client support for creation defaults. If talking to a 2.4+
-// cluster, you can use -1 for partitions and replicationFactor to use broker
-// defaults.
-//
-// This package includes a StringPtr function to aid in building config values.
-//
-// If the topic could not be created this function will return an error. An
-// error may be returned due to authorization failure, a failed network
-// request, a missing controller or other issues. If the request was successful
-// but the CreateTopicResponse.Err is non-nil, this returns the error, so you
-// do not need to additionally check the Err field.
+// replication factor, and (optional) configs for the given topic name.
+// This is similar to CreateTopics, but returns the kerr.ErrorForCode(response.ErrorCode)
+// if the request/response is successful.
 func (cl *Client) CreateTopic(
 	ctx context.Context,
 	partitions int32,
@@ -277,8 +274,34 @@ func (rs DeleteTopicResponses) On(topic string, fn func(*DeleteTopicResponse) er
 	return DeleteTopicResponse{}, kerr.UnknownTopicOrPartition
 }
 
+// Error iterates over all responses and returns the first error
+// encountered, if any.
+func (rs DeleteTopicResponses) Error() error {
+	for _, r := range rs {
+		if r.Err != nil {
+			return r.Err
+		}
+	}
+	return nil
+}
+
+// DeleteTopic issues a delete topic request for the given topic name with a
+// (by default) 15s timeout. This is similar to DeleteTopics, but returns the
+// kerr.ErrorForCode(response.ErrorCode) if the request/response is successful.
+func (cl *Client) DeleteTopic(ctx context.Context, topic string) (DeleteTopicResponse, error) {
+	rs, err := cl.DeleteTopics(ctx, topic)
+	if err != nil {
+		return DeleteTopicResponse{}, err
+	}
+	r, exists := rs[topic]
+	if !exists {
+		return DeleteTopicResponse{}, errors.New("requested topic was not part of delete topic response")
+	}
+	return r, r.Err
+}
+
 // DeleteTopics issues a delete topics request for the given topic names with a
-// 15s timeout.
+// (by default) 15s timeout.
 //
 // This does not return an error on authorization failures, instead,
 // authorization failures are included in the responses. This only returns an
@@ -402,6 +425,19 @@ func (rs DeleteRecordsResponses) On(topic string, partition int32, fn func(*Dele
 	return DeleteRecordsResponse{}, kerr.UnknownTopicOrPartition
 }
 
+// Error iterates over all responses and returns the first error
+// encountered, if any.
+func (rs DeleteRecordsResponses) Error() error {
+	for _, ps := range rs {
+		for _, r := range ps {
+			if r.Err != nil {
+				return r.Err
+			}
+		}
+	}
+	return nil
+}
+
 // DeleteRecords issues a delete records request for the given offsets. Per
 // offset, only the Offset field needs to be set.
 //
@@ -498,6 +534,17 @@ func (rs CreatePartitionsResponses) On(topic string, fn func(*CreatePartitionsRe
 	return CreatePartitionsResponse{}, kerr.UnknownTopicOrPartition
 }
 
+// Error iterates over all responses and returns the first error
+// encountered, if any.
+func (rs CreatePartitionsResponses) Error() error {
+	for _, r := range rs {
+		if r.Err != nil {
+			return r.Err
+		}
+	}
+	return nil
+}
+
 // CreatePartitions issues a create partitions request for the given topics,
 // adding "add" partitions to each topic. This request lets Kafka choose where
 // the new partitions should be.