Help Center> Object Storage Migration Service> API Reference> API v2 (Recommended)> Operations on Buckets> Checking Whether a Source Bucket Has Objects with a Specified Prefix
Updated on 2024-03-20 GMT+08:00

Checking Whether a Source Bucket Has Objects with a Specified Prefix

Function

This API is used to check whether there are objects with a specified prefix in a source bucket.

Calling Method

For details, see Calling APIs.

URI

POST /v2/{project_id}/objectstorage/buckets/prefix

Table 1 Path parameters

Parameter

Mandatory

Type

Description

project_id

Yes

String

The project ID.

Minimum length: 1 character

Maximum length: 1,024 characters

Request

Table 2 Request header parameters

Parameter

Mandatory

Type

Description

X-Auth-Token

Yes

String

The IAM token authentication. Ensure that the project ID contained in the token matches the project ID in the request URI.

Minimum length: 1 character

Maximum length: 16,384 characters

Table 3 Request body parameters

Parameter

Mandatory

Type

Description

cloud_type

Yes

String

The cloud service provider. The value can be AWS, Aliyun, Qiniu, QingCloud, Tencent, Baidu, KingsoftCloud, Azure, UCloud, HuaweiCloud, Google, URLSource, or HEC.

Default value: Aliyun

Minimum length: 0 characters

Maximum length: 100 characters

ak

No

String

The AK for accessing the source bucket. This parameter is mandatory when task_type is not url_list.

Minimum length: 0 characters

Maximum length: 100 characters

sk

No

String

The SK for accessing the destination bucket. This parameter is mandatory when task_type is not url_list.

Minimum length: 0 characters

Maximum length: 100 characters

json_auth_file

No

String

The file used for Google Cloud Storage authentication.

Minimum length: 0 characters

Maximum length: 65,535 characters

app_id

No

String

This parameter is mandatory when cloud_type is Tencent.

Minimum length: 0 characters

Maximum length: 255 characters

bucket_name

Yes

String

The bucket name.

Minimum length: 0 characters

Maximum length: 100 characters

file_name

Yes

String

The prefix.

Minimum length: 0 characters

Maximum length: 1,024 characters

data_center

Yes

String

The region.

Minimum length: 0 characters

Maximum length: 100 characters

security_token

No

String

The security token.

Minimum length: 0 characters

Maximum length: 16,384 characters

Response

Status code: 200

Table 4 Response body parameters

Parameter

Type

Description

exist

Boolean

Whether the prefix is found.

Default value: false

Status code: 400

Table 5 Response body parameters

Parameter

Type

Description

error_msg

String

The error message.

error_code

String

The error code.

Example Request

This example checks whether bucket xxx has objects with prefix xxxx.

POST https://{endpoint}/v2/{project_id}/objectstorage/buckets/prefix

{
  "cloud_type" : "HuaweiCloud",
  "ak" : "xxxxak",
  "sk" : "xxxxsk",
  "app_id" : "apptest123",
  "bucket_name" : "xxx",
  "file_name" : "xxxx",
  "data_center" : "cn-north-x",
  "security_token" : "string"
}

Example Response

Status code: 200

The prefix was found.

{
  "exist" : true
}

SDK Sample Code

The sample code is as follows:

This example checks whether bucket xxx has objects with prefix xxxx.

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package com.huaweicloud.sdk.test;

import com.huaweicloud.sdk.core.auth.ICredential;
import com.huaweicloud.sdk.core.auth.BasicCredentials;
import com.huaweicloud.sdk.core.exception.ConnectionException;
import com.huaweicloud.sdk.core.exception.RequestTimeoutException;
import com.huaweicloud.sdk.core.exception.ServiceResponseException;
import com.huaweicloud.sdk.oms.v2.region.OmsRegion;
import com.huaweicloud.sdk.oms.v2.*;
import com.huaweicloud.sdk.oms.v2.model.*;


public class CheckPrefixSolution {

    public static void main(String[] args) {
        // The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
        // In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
        String ak = System.getenv("CLOUD_SDK_AK");
        String sk = System.getenv("CLOUD_SDK_SK");

        ICredential auth = new BasicCredentials()
                .withAk(ak)
                .withSk(sk);

        OmsClient client = OmsClient.newBuilder()
                .withCredential(auth)
                .withRegion(OmsRegion.valueOf("<YOUR REGION>"))
                .build();
        CheckPrefixRequest request = new CheckPrefixRequest();
        CheckPrefixReq body = new CheckPrefixReq();
        body.withAppId("apptest123");
        body.withDataCenter("cn-north-x");
        body.withAk("xxxxak");
        body.withSk("xxxxsk");
        body.withBucketName("xxx");
        body.withFileName("xxxx");
        body.withSecurityToken("string");
        body.withCloudType("HuaweiCloud");
        request.withBody(body);
        try {
            CheckPrefixResponse response = client.checkPrefix(request);
            System.out.println(response.toString());
        } catch (ConnectionException e) {
            e.printStackTrace();
        } catch (RequestTimeoutException e) {
            e.printStackTrace();
        } catch (ServiceResponseException e) {
            e.printStackTrace();
            System.out.println(e.getHttpStatusCode());
            System.out.println(e.getRequestId());
            System.out.println(e.getErrorCode());
            System.out.println(e.getErrorMsg());
        }
    }
}

This example checks whether bucket xxx has objects with prefix xxxx.

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# coding: utf-8

from huaweicloudsdkcore.auth.credentials import BasicCredentials
from huaweicloudsdkoms.v2.region.oms_region import OmsRegion
from huaweicloudsdkcore.exceptions import exceptions
from huaweicloudsdkoms.v2 import *

if __name__ == "__main__":
    # The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
    # In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
    ak = __import__('os').getenv("CLOUD_SDK_AK")
    sk = __import__('os').getenv("CLOUD_SDK_SK")

    credentials = BasicCredentials(ak, sk) \

    client = OmsClient.new_builder() \
        .with_credentials(credentials) \
        .with_region(OmsRegion.value_of("<YOUR REGION>")) \
        .build()

    try:
        request = CheckPrefixRequest()
        request.body = CheckPrefixReq(
            app_id="apptest123",
            data_center="cn-north-x",
            ak="xxxxak",
            sk="xxxxsk",
            bucket_name="xxx",
            file_name="xxxx",
            security_token="string",
            cloud_type="HuaweiCloud"
        )
        response = client.check_prefix(request)
        print(response)
    except exceptions.ClientRequestException as e:
        print(e.status_code)
        print(e.request_id)
        print(e.error_code)
        print(e.error_msg)

This example checks whether bucket xxx has objects with prefix xxxx.

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package main

import (
	"fmt"
	"github.com/huaweicloud/huaweicloud-sdk-go-v3/core/auth/basic"
    oms "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/oms/v2"
	"github.com/huaweicloud/huaweicloud-sdk-go-v3/services/oms/v2/model"
    region "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/oms/v2/region"
)

func main() {
    // The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
    // In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
    ak := os.Getenv("CLOUD_SDK_AK")
    sk := os.Getenv("CLOUD_SDK_SK")

    auth := basic.NewCredentialsBuilder().
        WithAk(ak).
        WithSk(sk).
        Build()

    client := oms.NewOmsClient(
        oms.OmsClientBuilder().
            WithRegion(region.ValueOf("<YOUR REGION>")).
            WithCredential(auth).
            Build())

    request := &model.CheckPrefixRequest{}
	appIdCheckPrefixReq:= "apptest123"
	akCheckPrefixReq:= "xxxxak"
	skCheckPrefixReq:= "xxxxsk"
	securityTokenCheckPrefixReq:= "string"
	request.Body = &model.CheckPrefixReq{
		AppId: &appIdCheckPrefixReq,
		DataCenter: "cn-north-x",
		Ak: &akCheckPrefixReq,
		Sk: &skCheckPrefixReq,
		BucketName: "xxx",
		FileName: "xxxx",
		SecurityToken: &securityTokenCheckPrefixReq,
		CloudType: "HuaweiCloud",
	}
	response, err := client.CheckPrefix(request)
	if err == nil {
        fmt.Printf("%+v\n", response)
    } else {
        fmt.Println(err)
    }
}

For more SDK sample code of programming languages, visit API Explorer and click the Sample Code tab. Example code can be automatically generated.

Status Codes

Status Code

Description

200

The prefix was found.

400

Standard error response.

Error Codes

For details, see Error Codes.