ticdc: remove canal protocol document (#16773) (#16794)

ticdc/ticdc-faq.md

@@ -108,20 +108,20 @@ If you use the `cdc cli changefeed create` command without specifying the `-conf
 - Replicates all tables except system tables
 - Only replicates tables that contain [valid indexes](/ticdc/ticdc-overview.md#best-practices)
 
-## Does TiCDC support outputting data changes in the Canal format?
+## Does TiCDC support outputting data changes in the Canal protocol?
 
-Yes. To enable Canal output, specify the protocol as `canal` in the `--sink-uri` parameter. For example:
+Yes. Note that for the Canal protocol, TiCDC only supports the JSON output format, while the protobuf format is not officially supported yet. To enable Canal output, specify `protocol` as `canal-json` in the `--sink-uri` configuration. For example:
 
 {{< copyable "shell-regular" >}}
 
 ```shell
-cdc cli changefeed create --server=http://127.0.0.1:8300 --sink-uri="kafka://127.0.0.1:9092/cdc-test?kafka-version=2.4.0&protocol=canal" --config changefeed.toml
+cdc cli changefeed create --server=http://127.0.0.1:8300 --sink-uri="kafka://127.0.0.1:9092/cdc-test?kafka-version=2.4.0&protocol=canal-json" --config changefeed.toml
 ```
 
 > **Note:**
 >
 > * This feature is introduced in TiCDC 4.0.2.
-> * TiCDC currently supports outputting data changes in the Canal format only to MQ sinks such as Kafka.
+> * TiCDC currently supports outputting data changes in the Canal-JSON format only to MQ sinks such as Kafka.
 
 For more information, refer to [TiCDC changefeed configurations](/ticdc/ticdc-changefeed-config.md).
 

ticdc/ticdc-open-api-v2.md

@@ -332,7 +332,7 @@ The `sink` parameters are described as follows:
 | `date_separator`        | `STRING` type. Indicates the date separator type of the file directory. Value options are `none`, `year`, `month`, and `day`. `none` is the default value and means that the date is not separated. (Optional) |
 | `dispatchers`           | An configuration array for event dispatching. (Optional)                                                                                                                                                       |
 | `encoder_concurrency`   | `INT` type. The number of encoder threads in the MQ sink. The default value is `16`. (Optional)                                                                                                                |
-| `protocol`              | `STRING` type. For MQ sinks, you can specify the protocol format of the message. The following protocols are currently supported: `canal-json`, `open-protocol`, `canal`, `avro`, and `maxwell`.               |
+| `protocol`              | `STRING` type. For MQ sinks, you can specify the protocol format of the message. The following protocols are currently supported: `canal-json`, `open-protocol`, `avro`, and `maxwell`.               |
 | `schema_registry`       | `STRING` type. The schema registry address. (Optional)                                                                                                                                                         |
 | `terminator`            | `STRING` type. The terminator is used to separate two data change events. The default value is null, which means `"\r\n"` is used as the terminator. (Optional)                                                |
 | `transaction_atomicity` | `STRING` type. The atomicity level of the transaction. (Optional)                                                                                                                                              |

ticdc/ticdc-open-api.md

@@ -163,7 +163,7 @@ The configuration parameters of sink are as follows:
 
 `matcher`: The matching syntax of matcher is the same as the filter rule syntax.
 
-`protocol`: For the sink of MQ type, you can specify the protocol format of the message. Currently the following protocols are supported: `canal-json`, `open-protocol`, `canal`, `avro`, and `maxwell`.
+`protocol`: For the sink of MQ type, you can specify the protocol format of the message. Currently the following protocols are supported: `canal-json`, `open-protocol`, `avro`, and `maxwell`.
 
 ### Example
 

ticdc/ticdc-sink-to-kafka.md

@@ -59,7 +59,7 @@ The following are descriptions of sink URI parameters and values that can be con
 | `replication-factor` | The number of Kafka message replicas that can be saved (optional, `1` by default). This value must be greater than or equal to the value of [`min.insync.replicas`](https://kafka.apache.org/33/documentation.html#brokerconfigs_min.insync.replicas) in Kafka. |
 | `required-acks` | A parameter used in the `Produce` request, which notifies the broker of the number of replica acknowledgements it needs to receive before responding. Value options are `0` (`NoResponse`: no response, only `TCP ACK` is provided), `1` (`WaitForLocal`: responds only after local commits are submitted successfully), and `-1` (`WaitForAll`: responds after all replicated replicas are committed successfully. You can configure the minimum number of replicated replicas using the [`min.insync.replicas`](https://kafka.apache.org/33/documentation.html#brokerconfigs_min.insync.replicas) configuration item of the broker). (Optional, the default value is `-1`).    |
 | `compression` | The compression algorithm used when sending messages (value options are `none`, `lz4`, `gzip`, `snappy`, and `zstd`; `none` by default). Note that the Snappy compressed file must be in the [official Snappy format](https://github.com/google/snappy). Other variants of Snappy compression are not supported.|
-| `protocol` | The protocol with which messages are output to Kafka. The value options are `canal-json`, `open-protocol`, `canal`, `avro` and `maxwell`.   |
+| `protocol` | The protocol with which messages are output to Kafka. The value options are `canal-json`, `open-protocol`, `avro` and `maxwell`.   |
 | `auto-create-topic` | Determines whether TiCDC creates the topic automatically when the `topic-name` passed in does not exist in the Kafka cluster (optional, `true` by default). |
 | `enable-tidb-extension` | Optional. `false` by default. When the output protocol is `canal-json`, if the value is `true`, TiCDC sends [WATERMARK events](/ticdc/ticdc-canal-json.md#watermark-event) and adds the [TiDB extension field](/ticdc/ticdc-canal-json.md#tidb-extension-field) to Kafka messages. From v6.1.0, this parameter is also applicable to the `avro` protocol. If the value is `true`, TiCDC adds [three TiDB extension fields](/ticdc/ticdc-avro-protocol.md#tidb-extension-fields) to the Kafka message. |
 | `max-batch-size` | New in v4.0.9. If the message protocol supports outputting multiple data changes to one Kafka message, this parameter specifies the maximum number of data changes in one Kafka message. It currently takes effect only when Kafka's `protocol` is `open-protocol` (optional, `16` by default). |