Configuring Back-to-Source-by-Mirroring Rules

rules

Yes

Container

Definition:

Number of rules. rules is the parent node of id, condition, and redirect.

Constraints:

For the same bucket, prefixes of different rules cannot contain each other or have duplicate starting characters. The same agency is recommended.

Range:

A maximum of 10 back-to-source-by-mirroring rules can be created for each bucket. Therefore, the value range of the array length is from 1 to 10. For details, see Table 2.

Default value:

None

id

Yes

String

Definition:

Unique ID of a back-to-source rule configured for the current bucket.

Constraints:

The rule ID must be unique in the bucket.

Range:

The value is a string of 1 to 256 characters. Only uppercase letters, lowercase letters, digits, underscores (_), and hyphens (-) are allowed.

Default value:

None

condition

Yes

Container

Definition:

Condition for triggering back-to-source. This parameter is the parent node of httpErrorCodeReturnedEquals and objectKeyPrefixEquals.

Constraints:

None

Range:

For details, see Table 3.

Default value:

None

redirect

Yes

Container

Definition:

Parameters for implementing the back-to-source function. This parameter is the parent node of agency, publicSource, retryConditions, passQueryString, mirrorFollowRedirect, replaceKeyWith, replaceKeyPrefixWith, vpcEndpointURN, redirectWithoutReferer, and mirrorAllowHttpMethod.

Constraints:

None

Range:

For details, see Table 4.

Default value:

None

httpErrorCodeReturnedEquals

Yes

Integer

Definition:

Error code that triggers the back-to-source function. When this error is returned for a download request, the back-to-source function is triggered.

Constraints:

None

Range:

404: The object does not exist in the OBS bucket.

Default value:

404

objectKeyPrefixEquals

No

String

Definition:

Prefix of the object name that triggers the back-to-source function. The back-to-source function is performed only when the specified object name prefix is contained in the request.

Constraints:

• If this parameter is left blank, all objects are matched by default.
• For the same bucket, prefixes of different rules cannot contain each other or have duplicate beginning characters.

Range:

The value is a string of 0 to 1023 characters and can contain any characters.

Default value:

None

agency

Yes

String

Definition:

Agency name. With an agency, the customer can grant OBS the permissions to query whether a specified object exists in the bucket and to upload objects to the bucket.

Constraints:

None

Range:

None

Default value:

None

publicSource

No

Container

Definition:

Configuration of the source that can be publicly accessed. This parameter is mandatory when the source is a public accessible resource. publicSource is the parent node of sourceEndpoint.

Constraints:

None

Range:

For details, see Table 5.

Default value:

None

retryConditions

No

Array

Definition:

Condition for switching the source address.

Constraints:

4XX and error codes starting with 4 cannot be configured together. 5XX and error codes starting with 5 cannot be configured together.

Range:

4XX, 5XX, 400–499, and 500–599 (a maximum of 20 error codes can be configured at the same time)

Default value:

None

passQueryString

Yes

Boolean

Definition:

Whether to carry the request character string.

Constraints:

If this parameter is set to true but the query parameter contains the signature information, the signature information is removed and the remaining parameters are passed.

Range:

• false: The queryString value in the OBS request is not passed to the source.
• true: The queryString value in the OBS request is passed to the source.

Default value:

false

mirrorFollowRedirect

Yes

Boolean

Definition:

Whether to obtain resources by redirecting the request based on the 3XX response from the source

Constraints:

None

Range:

• false: OBS transparently passes the 3XX response and does not return resources.
• true: OBS returns resources by redirecting the request based on the 3XX response.

Default value:

false

mirrorHttpHeader

No

Container

Definition:

Rules for passing HTTP headers. mirrorHttpHeader is the parent node of passAll, pass, remove, and set.

Constraints:

None

Range:

For details, see Table 7.

Default value:

None

replaceKeyWith

No

String

Definition:

Whether to add a prefix or suffix when downloading objects from the source.

Constraints:

If both replaceKeyWith and ReplaceKeyPrefixWith are left blank, ReplaceKeyPrefixWith takes effect. The request is invalid if both the parameters are specified.

Range:

• prefix${key}suffix: The prefix or suffix needs to be added.
• ${key}: No prefix or suffix needs to be added.

${key} indicates keywords. The total length of the prefix and suffix ranges from 0 to 1023.

Default value:

None

replaceKeyPrefixWith

No

String

Definition:

Character string used to replace objectKeyPrefixEquals. If you need to replace the current object name prefix when downloading the object from the source, specify this parameter.

Constraints:

If both replaceKeyWith and ReplaceKeyPrefixWith are left blank, ReplaceKeyPrefixWith takes effect. The request is invalid if both the parameters are specified.

Range:

The value is a string of 0 to 1023 characters.

Default value:

None

vpcEndpointURN

No

String

Definition:

URN of VPC Endpoint service.

Constraints:

None

Range:

The value is a string of 0 to 127 characters.

Default value:

None

redirectWithoutReferer

No

Boolean

Definition:

Whether to skip carrying the original host as the referer header to the destination address for redirection.

Constraints:

None

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.

Default value:

false

mirrorAllowHttpMethod

No

Array

Definition:

Request method that supports transparent transmission.

Constraints:

None

Range:

• GET: requests to obtain objects in a bucket
• HEAD: requests to obtain the metadata of an object in a bucket

Default value:

None

sourceEndpoint

No

Container

Definition:

Source address that can be publicly accessed. sourceEndpoint is the parent node of master and slave.

Constraints:

None

Range:

For details, see Table 6.

Default value:

None

master

No

Array

Definition:

Master source address. If the source is a bucket that can be accessed over HTTP network, the address is the bucket domain name. If the source is a private bucket provided by other cloud vendors, the address is a region domain name.

Constraints:

The master source address is preferentially used during the back-to-source process. If one to five master source addresses are configured, they are accessed in polling mode. If two or more master addresses are configured, when the first request fails and the retry conditions are met, an address other than the one involved in the first request is used to retry.

Range:

The format of a single source address is https://xxx.yyy.zzz or http://xxx.yyy.zzz. The value is a string of 10 to 255 characters.

Default value:

None

slave

No

Array

Definition:

Slave source address. If the source is a bucket that can be accessed over HTTP network, the address is the bucket domain name. If the source is a private bucket provided by other cloud vendors, the address is a region domain name.

Constraints:

A back-to-source request will retry a slave source address when master ones are not available. A maximum of five slave addresses can be configured.

Range:

The format of a single source address is https://xxx.yyy.zzz or http://xxx.yyy.zzz. The value is a string of 10 to 255 characters.

Default value:

None

passAll

No

Boolean

Definition:

Whether to pass all HTTP headers to the source.

Constraints:

• passAll and pass are mutually exclusive.
• The following HTTP header types do not support transparent transmission:
  1. Headers starting with the following prefixes:
     1. x-obs-
     2. x-amz-
  2. All standard HTTP headers, for example:
     1. Content-Length
     2. Authorization
     3. Date

Range:

• false: Do not transparently transmit all HTTP headers to the source.
• true: All HTTP headers are transparently transmitted to the source.

Default value:

false

pass

No

Array

Definition:

The list of HTTP headers to be transparently transmitted.

Constraints:

Only letters, digits, hyphens (-), and underscores (_) are allowed.

Range:

A maximum of 10 HTTP headers can be displayed. The length of each HTTP header ranges from 1 to 63.

Default value:

None

remove

No

Array

Definition:

List of HTTP headers that cannot be transparently transmitted.

Constraints:

• The remove operation takes precedence over the pass and passAll operations.
• Only letters, digits, hyphens (-), and underscores (_) are allowed.

Range:

A maximum of 10 HTTP headers can be displayed. The length of each HTTP header ranges from 1 to 63.

Default value:

None

set

No

Array

Definition:

List of HTTP header values to be transparently transmitted.

Constraints:

• The set operation has a higher priority than the remove, pass, and passAll operations.
• If a custom header contains the Referer header, redirectWithoutReferer must be set to true. Otherwise, there will be an overwriting.

Range:

A maximum of 10 HTTP headers can be displayed in a set. Each HTTP header contains a key and a value. For details about keys and values, see Table 8.

Default value:

None

key

No

String

Definition:

Keyword of the HTTP header that needs to be transparently transmitted.

Constraints:

• Each key is unique.
• Only letters, digits, hyphens (-), and underscores (_) are allowed.

Range:

The value is a string of 1 to 63 characters.

Default value:

None

value

No

String

Definition:

Value of the HTTP header that needs to be transparently transmitted.

Constraints:

None

Range:

The value is a string of 1 to 2048 characters.

Default value:

None