| package kafka |
| |
| /** |
| * Copyright 2018 Confluent Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| import ( |
| "fmt" |
| "strconv" |
| ) |
| |
| /* |
| #include <string.h> |
| #include <librdkafka/rdkafka.h> |
| #include "glue_rdkafka.h" |
| */ |
| import "C" |
| |
| // Header represents a single Kafka message header. |
| // |
| // Message headers are made up of a list of Header elements, retaining their original insert |
| // order and allowing for duplicate Keys. |
| // |
| // Key is a human readable string identifying the header. |
| // Value is the key's binary value, Kafka does not put any restrictions on the format of |
| // of the Value but it should be made relatively compact. |
| // The value may be a byte array, empty, or nil. |
| // |
| // NOTE: Message headers are not available on producer delivery report messages. |
| type Header struct { |
| Key string // Header name (utf-8 string) |
| Value []byte // Header value (nil, empty, or binary) |
| } |
| |
| // String returns the Header Key and data in a human representable possibly truncated form |
| // suitable for displaying to the user. |
| func (h Header) String() string { |
| if h.Value == nil { |
| return fmt.Sprintf("%s=nil", h.Key) |
| } |
| |
| valueLen := len(h.Value) |
| if valueLen == 0 { |
| return fmt.Sprintf("%s=<empty>", h.Key) |
| } |
| |
| truncSize := valueLen |
| trunc := "" |
| if valueLen > 50+15 { |
| truncSize = 50 |
| trunc = fmt.Sprintf("(%d more bytes)", valueLen-truncSize) |
| } |
| |
| return fmt.Sprintf("%s=%s%s", h.Key, strconv.Quote(string(h.Value[:truncSize])), trunc) |
| } |