You use the headers described in the table below to specify conditional operations.
Header | Value | Description |
---|---|---|
If-Match |
One of: •Comma-separated list of ETag values •asterisk (*) |
Perform the operation only if the ETag of the object or version is identical to one of the specified ETag values. For an asterisk, perform the operation if the object exists. |
If-None-Match |
One of: •Comma-separated list of ETag values •asterisk (*) |
Perform the operation only if the ETag of the object or version is not equal to any of the specified ETag values. For an asterisk, perform the operation if the object doesn’t exist. |
If-Modified-Since |
Datetime value |
Perform the operation only if the object or version change time was after the specified time. |
If-Unmodified- |
Datetime value |
Perform the operation only if the object or version change time was at or before the specified time. |
When you use the PUT method to copy an object, the headers listed in the table above apply to any existing version of the target object. You can use the headers describe in the table below to specify conditions for the source object.
Header | Contents | Description |
---|---|---|
X-HCP-CopySource-If- |
One of: •Comma-separated list of ETag values •asterisk (*) |
Perform the copy operation only if the ETag of the source object or version is equal to one of the specified ETag values. For an asterisk, perform the operation if the object exists. |
X-HCP-CopySource-If- |
One of: •Comma-separated list of ETag values •asterisk (*) |
Perform the copy operation only if the ETag of the source object or version is not equal to any of the specified ETag values. For an asterisk, perform the operation if the object does not exist. |
X-HCP-CopySource-If- |
Datetime value |
Perform the copy operation only if the source object or version change time was after the specified time. |
X-HCP-CopySource-If- |
Datetime value |
Perform the copy operation only if the source object or version change time was at or before the specified time. |
A request can specify more than one condition. In such a request:
•HCP evaluates all the conditions. However, if the request includes both If-None-Match and If-Modified-Since headers, the If-Modified-Since header is ignored.
•Headers that use ETag values are processed before headers that use datetime values.
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