Obtaining Back-to-Source by Mirroring Rules (SDK for Java)

Function

This API is used to obtain the back-to-source by mirroring rules of a bucket.

Restrictions

To obtain the back-to-source by mirroring rules of a bucket, you must be the bucket owner or have the required permission (obs:bucket:GetMirrorBackToSource granted using IAM or GetMirrorBackToSource granted using a bucket policy). For details, see Introduction to OBS Access Control, IAM Custom Policies, and Creating a Custom Bucket Policy.

The mapping between OBS regions and endpoints must comply with what is listed in Regions and Endpoints.

Method

obsClient.getBucketMirrorBackToSource(GetBucketMirrorBackToSourceRequest request)

Request Parameters

**Table 1** List of request parameters
Parameter	Type	Mandatory (Yes/No)	Description
request	Table 2	Yes	Explanation: Request parameters for obtaining the back-to-source by mirroring rules. For details, see Table 2.

**Table 2** GetBucketMirrorBackToSourceRequest
Parameter	Type	Mandatory (Yes/No)	Description
bucketName	String	Yes	Explanation: Bucket name Restrictions: A bucket name must be unique across all accounts and regions. A bucket name: Must be 3 to 63 characters long and start with a digit or letter. Lowercase letters, digits, hyphens (-), and periods (.) are allowed. Cannot be formatted as an IP address. Cannot start or end with a hyphen (-) or period (.). Cannot contain two consecutive periods (..), for example, my..bucket. Cannot contain a period (.) and a hyphen (-) adjacent to each other, for example, my-.bucket or my.-bucket. If you repeatedly create buckets with the same name in the same region, no error will be reported and the bucket properties comply with those set in the first creation request. Default value: None

Responses

**Table 3** GetBucketTrashResult
Parameter	Type	Description
statusCode	int	Explanation: HTTP status code Value range: A status code is a group of digits indicating the status of a response. It ranges from 2xx (indicating successes) to 4xx or 5xx (indicating errors). For more information, see Status Code. Default value: None
responseHeaders	Map<String, Object>	Explanation: HTTP response header list, composed of tuples. In a tuple, the String key indicates the name of the header, and the Object value indicates the value of the header. Default value: None
mirrorBackToSourceConfiguration	Table 4	Explanation: Back-to-source by mirroring configuration. For details, see Table 4.

**Table 4** MirrorBackToSourceConfiguration
Parameter	Type	Description
rules	List<Table 5>	Explanation: List of back-to-source by mirroring rules. For details, see Table 5.

**Table 5** MirrorBackToSourceRule
Parameter	Type	Description
id	String	Explanation: Rule ID. It is the unique identifier of the back-to-source by mirroring rule configured for the current bucket.
condition	Table 6	Explanation: Condition for triggering back to source. For details, see Table 6.
redirect	Table 7	Explanation: Parameters for implementing the back to source function. For details, see Table 7.

**Table 6** MirrorBackCondition
Parameter	Type	Description
httpErrorCodeReturnedEquals	String	Explanation: Error code that triggers the back to source function. When this error code is returned for a download request, the back to source function is triggered. Default value: 404
objectKeyPrefixEquals	String	Explanation: Prefix of the object name that triggers the back to source function. Back to source is performed only when the specified object name prefix is contained in the request. Restrictions: If this parameter is left blank, all objects can trigger the back to source function. For the same bucket, prefixes of different rules cannot be the same or contain each other.

**Table 7** MirrorBackRedirect
Parameter	Type	Description
agency	String	Explanation: Agency name. With an agency, you can grant OBS the permissions to query whether a specified object exists in a bucket and to upload objects to a bucket.
publicSource	Table 8	Explanation: Configuration of the source site that can be publicly accessed. This parameter is mandatory when the source site is a publicly accessible resource. publicSource is the parent node of sourceEndpoint. For details, see Table 8.
vpcEndpointURN	String	Explanation: URN of the VPC endpoint service
retryConditions	List<String>	Explanation: Condition for switching the source site address
passQueryString	Boolean	Explanation: Whether to include the request character string Value range: false: queryString in the OBS request is not passed to the source site. true: queryString in the OBS request is passed to the source site.
mirrorFollowRedirect	Boolean	Explanation: Whether to obtain resources by redirecting the request based on the 3XX response from the source site Value range: false: OBS transparently transmits the 3XX response and does not return resources. true: OBS returns resources by redirecting the request based on the 3XX response.
mirrorHttpHeader	Table 10	Explanation: HTTP header pass rule. mirrorHttpHeader is the parent node of passAll, pass, remove, and set. For details, see Table 10.
replaceKeyWith	String	Explanation: Whether to add a prefix or suffix when downloading objects from the source site
replaceKeyPrefixWith	String	Explanation: Character string used to replace objectKeyPrefixEquals. If you need to replace the current object name prefix when downloading the object from the source site, specify this parameter.
redirectWithoutReferer	Boolean	Explanation: Whether to carry the original host as the referer header to the destination address for redirection Value range: false: The original host is carried as the referer header to the destination address for redirection. true: The original host is not carried as the referer header to the destination address for redirection.
mirrorAllowHttpMethod	List<String>	Explanation: Request method that supports transparent transmission Value range: GET: requests to obtain objects in a bucket HEAD: requests to obtain the metadata of an object in a bucket

**Table 8** MirrorBackPublicSource
Parameter	Type	Mandatory (Yes/No)	Description
sourceEndpoint	Table 9	No	Explanation: Address of the source site that can be publicly accessed. sourceEndpoint is the parent node of master and slave. For details, see Table 9.

**Table 9** MirrorBackSourceEndpoint
Parameter	Type	Mandatory (Yes/No)	Description
master	List<String>	No	Explanation: Primary source site address. If the source site is a bucket that can be accessed over HTTP, the address is the bucket domain name. If the source site is a private bucket provided by other cloud vendors, the address is the region domain name.
slave	List<String>	No	Explanation: Secondary source site address. If the source site is a bucket that can be accessed over HTTP, the address is the bucket domain name. If the source site is a private bucket provided by other cloud vendors, the address is the region domain name.

**Table 10** MirrorBackHttpHeader
Parameter	Type	Mandatory (Yes/No)	Description
passAll	Boolean	No	Explanation: Whether to transparently transmit all HTTP headers to the source site Value range: false: Do not transparently transmit all HTTP headers to the source site. true: Transparently transmit all HTTP headers to the source site.
pass	List<String>	No	Explanation: List of HTTP headers to be transparently transmitted
remove	List<String>	No	Explanation: List of HTTP headers that cannot be transparently transmitted
set	List<Table 11>	No	Explanation: List of HTTP header values to be transparently transmitted. For details, see Table 11.

**Table 11** MirrorBackHttpHeaderSet
Parameter	Type	Mandatory (Yes/No)	Description
key	String	No	Explanation: Keyword of the HTTP header that needs to be transparently transmitted
value	String	No	Explanation: Value of the HTTP header that needs to be transparently transmitted

Sample Code

This example obtains the back-to-source by mirroring configuration of bucket examplebucket.

import com.obs.services.ObsClient;
import com.obs.services.exception.ObsException;
import com.obs.services.model.mirrorback.GetBucketMirrorBackToSourceRequest;
import com.obs.services.model.mirrorback.GetBucketMirrorBackToSourceResult;
import com.obs.services.model.mirrorback.MirrorBackRedirect;
import com.obs.services.model.mirrorback.MirrorBackSourceEndpoint;
import com.obs.services.model.mirrorback.MirrorBackToSourceConfiguration;
import com.obs.services.model.mirrorback.MirrorBackToSourceRule;
public class GetBucketMirrorBackToSource {
    public static void main(String[] args) {
        // Obtain an AK/SK pair using environment variables or import the AK/SK pair in other ways. Using hard coding may result in leakage.
        // Obtain an AK/SK pair on the management console.
        String ak = System.getenv("ACCESS_KEY_ID");
        String sk = System.getenv("SECRET_ACCESS_KEY_ID");
        // (Optional) If you are using a temporary AK/SK pair and a security token to access OBS, you are not advised to use hard coding, which may result in information leakage.
        // Obtain an AK/SK pair and a security token using environment variables or import them in other ways.
        String securityToken = System.getenv("SECURITY_TOKEN");
        // Enter the endpoint corresponding to the bucket. CN North-Beijing4 is used here as an example. Replace it with the one currently in use.
        // Obtain an endpoint using environment variables or import it in other ways.
        String endPoint = System.getenv("ENDPOINT");
        ObsConfiguration obsConfiguration = new ObsConfiguration();
        obsConfiguration.setEndPoint(endPoint);
        ObsClient obsClient = new ObsClient(ak, sk, securityToken, obsConfiguration);
        try {
            String exampleBucket = "examplebucket";
            GetBucketMirrorBackToSourceRequest request = new GetBucketMirrorBackToSourceRequest(exampleBucket);
            GetBucketMirrorBackToSourceResult result = obsClient.getBucketMirrorBackToSource(request);
            System.out.println("GetBucketMirrorBackToSource successfully");
            MirrorBackToSourceConfiguration config = result.getMirrorBackToSourceConfiguration();
            if (config != null && config.getRules() != null) {
                for (MirrorBackToSourceRule rule : config.getRules()) {
                    System.out.println("Rule ID: " + rule.getId());
                    if (rule.getCondition() != null) {
                        System.out.println("Condition HTTP Error Code: "
                            + rule.getCondition().getHttpErrorCodeReturnedEquals());
                        System.out.println("Condition Object Key Prefix: "
                            + rule.getCondition().getObjectKeyPrefixEquals());
                    }
                    if (rule.getRedirect() != null) {
                        MirrorBackRedirect redirect = rule.getRedirect();
                        System.out.println("Agency: " + redirect.getAgency());
                        System.out.println("Pass Query String: " + redirect.getPassQueryString());
                        System.out.println("Mirror Follow Redirect: " + redirect.getMirrorFollowRedirect());
                        if (redirect.getPublicSource() != null
                            && redirect.getPublicSource().getSourceEndpoint() != null) {
                            MirrorBackSourceEndpoint ep =
                                redirect.getPublicSource().getSourceEndpoint();
                            System.out.println("Master Endpoints: " + ep.getMaster());
                            System.out.println("Slave Endpoints: " + ep.getSlave());
                        }
                    }
                }
            }
        } catch (ObsException e) {
            System.out.println("GetBucketMirrorBackToSource failed");
            // Request failed. Print the HTTP status code.
            System.out.println("HTTP Code:" + e.getResponseCode());
            // Request failed. Print the server-side error code.
            System.out.println("Error Code:" + e.getErrorCode());
            // Request failed. Print the error details.
            System.out.println("Error Message:" + e.getErrorMessage());
            // Request failed. Print the request ID.
            System.out.println("Request ID:" + e.getErrorRequestId());
            System.out.println("Host ID:" + e.getErrorHostId());
            e.printStackTrace();
        } catch (Exception e) {
            System.out.println("GetBucketMirrorBackToSource failed");
            // Print other error information.
            e.printStackTrace();
        }
    }
}

Helpful Links

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