Querying Messages

Function

This API is used to query the offset and content of a message.

This API queries the message offset based on the timestamp and then queries the message content based on the offset.

Calling Method

For details, see Calling APIs.

URI

GET /v2/{project_id}/instances/{instance_id}/messages

**Table 1** Path Parameters
Parameter	Mandatory	Type	Description
project_id	Yes	String	Project ID. For details about how to obtain it, see Obtaining a Project ID.
instance_id	Yes	String	Instance ID.

**Table 2** Query Parameters
Parameter	Mandatory	Type	Description
topic	Yes	String	Topic name. A topic name must start with a letter and can only contain letters, hyphens (-), underscores (_), and digits.
asc	No	Boolean	Whether to sort messages by time.
start_time	No	String	Start time. The value is a Unix timestamp, in millisecond. This parameter is mandatory when you query the message offset.
end_time	No	String	End time. The value is a Unix timestamp, in millisecond. This parameter is mandatory when you query the message offset.
limit	No	String	Number of messages displayed on each page.
offset	No	String	Page number.
download	No	Boolean	Whether download is required.
message_offset	No	String	Message offset. This parameter is mandatory when you query the message content. If start_time and end_time are not empty, this parameter is invalid.
partition	No	String	Partition. This parameter is mandatory when you query the message content. If start_time and end_time are not empty, this parameter is invalid.
keyword	No	String	Keyword. The value ranges from 0 to 50.

Request Parameters

None

Response Parameters

Status code: 200

**Table 3** Response body parameters
Parameter	Type	Description
messages	Array of MessagesEntity objects	Message list.
total	Long	Total number of messages.
size	Long	Number of records on each page.

**Table 4** MessagesEntity
Parameter	Type	Description
topic	String	Topic name.
partition	Integer	Partition where the message is located.
key	String	Message key.
value	String	Message content.
size	Integer	Message size.
timestamp	Long	Message production time. The value is a UNIX timestamp, in ms.
huge_message	Boolean	Big data flag.
message_offset	Long	Message offset.
message_id	String	Message ID.
app_id	String	Application ID.
tag	String	Message label.

Status code: 400

**Table 5** Response body parameters
Parameter	Type	Description
error_code	String	Error code.
error_msg	String	Error description.

Status code: 403

**Table 6** Response body parameters
Parameter	Type	Description
error_code	String	Error code.
error_msg	String	Error description.

Example Requests

Querying the message offset.

GET https://{endpoint}/v2/{project_id}/instances/{instance_id}/messages?asc=false&end_time=1608609032042&limit=10&offset=0&start_time=1608608432042&topic=topic-test

Querying the message content.

GET https://{endpoint}/v2/{project_id}/instances/{instance_id}/messages?download=false&message_offset=0&partition=0&topic=topic-test

Example Responses

Status code: 200

The query is successful.

{
  "messages" : [ {
    "topic" : "topic-test",
    "partition" : 0,
    "value" : "hello world",
    "size" : 21,
    "timestamp" : 1607598463502,
    "huge_message" : false,
    "message_offset" : 4,
    "message_id" : "",
    "app_id" : "",
    "tag" : ""
  } ],
  "total" : 1,
  "size" : 1
}