Object Storage Objects
Learn about how to manageObject Storage objects, which are files or unstructured data that you can upload to an Object Storage bucket to a compartment.
In the Object Storage service, an object is a file or unstructured data you upload to a bucket within a compartment within an Object Storage namespace. The object can be any type of data, for example, multimedia files, data backups, static web content, or logs. You can store objects that are up to 10 TiB. Objects are processed as a single entity. You can't edit or append data to an object, but you can replace the entire object.
Object Storage allows versioning of objects, which creates an accessible and downloadable copy of a particular version of an object you uploaded to a bucket. Object versioning protects objects from accidental or malicious overwrite or deletion. For more information, see Object Storage Versioning.
These topics describes how to manage objects within a single bucket. For information on copying an object to another bucket, see Copying Objects.
Using Objects
You can perform the following Object Storage object tasks:
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Search for objects in a bucket based on the object name's prefix
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Get a bucket's details, such as its entity tag or storage tier
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Check the status of an object being restored from Archive Storage
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Synchronize a file system directory with objects in a bucket
You can perform certain tasks on a group of objects at a time using the Command Line Interface. See Bulk Object Tasks for more information.
Required IAM Policy
To use Oracle Cloud Infrastructure, you must be granted security access in a policy by an administrator. This access is required whether you're using the Console or the REST API with an SDK, CLI, or other tool. If you get a message that you don't have permission or are unauthorized, verify with your administrator what type of access you have and which compartment to work in.
If you're new to policies, see Getting Started with Policies and Common Policies.
For administrators:
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The policy Let Object Storage admins manage buckets and objects lets the specified group do everything with buckets and objects. Objects always reside in the same compartment as the bucket.
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If you need to write a more restrictive policy for objects, the
inspect objects
lets you list all the objects in a bucket and do a HEAD operation for a particular object. In comparison,read objects
lets you download the object itself. -
To create more restrictive policies that grant individual permissions:
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OBJECT_VERSION_DELETE is required to delete previous object versions on your behalf using lifecycle policies.
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OBJECT_UPDATE_TIER is required to change the storage tier of an object.
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See Details for Object Storage, Archive Storage, and Data Transfer for more information on Object Storage user permissions.
IAM Policies for Objects
Sometimes having bucket-level access control is insufficient for your security needs. Instead, having a more granular control at an individual or prefix- or suffix-based group of objects is required. For example, if you're part of a group which is authorized for a specific object to get a work request, you need an Identity and Access Management IAM policy that gives permission for that operation explicitly.
Object-level IAM policies let you grant permission to specific objects and subsets of objects within an Object Storage bucket. The IAM policy variable target.object.name
gives you the ability to apply authorization and permissions to objects, similar to what you can do with tenancies, compartments, and buckets. For example:
ALLOW GROUP object-authZ-op-group-ost-object TO manage objects IN TENANCY where any {target.object.name = 'ost-object-*', request.operation = 'GetObject'}
Object-level IAM policies are especially useful to big data and data lake use cases where a single bucket has many different datasets and is accessed by several teams or workloads.
To create object-level IAM policies, follow the steps as described in Creating a Policy. Add policy statements for object-level IAM using the following syntax:
ALLOW GROUP <group> TO manage objects IN TENANCY where all {target.object.name = '<object-pattern>', target.bucket.name = '<bucket_name>'}
Authorization is evaluated for object-level IAM policies when the request arrives for an object on the server.
You need permissions for listing the buckets in a compartment and listing the objects in a bucket to list the specific object or object patterns when using the Console. You must have READ permissions to access the objects that are listed.
If the object name or path is already known and is being accessed using the CLI or API, you don't need these compartment or bucket access permissions.
There might be a delay of several minutes for any object policies you apply to become effective. This delay is applicable to all policies you create or update that control the access to Object Storage resources.
You can also update an existing policy to include object-level IAM permissions. See Updating a Policy's Statements. Object-level IAM policies are compatible with all existing policy constructs.
Example 1: Allowing full access to a group for a folder in a bucket:
ALLOW group test-group TO manage objects IN TENANCY where all {target.bucket.name = 'test-bucket', target.object.name = 'prod/*'}
Example 2: Allowing read-only access to a group for a folder in a bucket:
ALLOW group test-group TO manage objects IN TENANCY where all {target.bucket.name = 'test-bucket', target.object.name = 'prod/*', any{request.permission='OBJECT_INSPECT', request.permission='OBJECT_READ'}}
Example 3: Allowing write-once (no overwrites) and no read or delete access to a group for a folder:
ALLOW group test-group TO manage objects IN TENANCY where all {target.bucket.name = 'test-bucket', target.object.name = 'prod/*', any{request.permission='OBJECT_CREATE'}}
Example 4: Allowing read and write access to a group for a folder in a bucket (no listing or overwriting):
ALLOW group test-group TO manage objects IN TENANCY where all {target.bucket.name = 'test-bucket', target.object.name = 'prod/*', any{request.permission='OBJECT_CREATE', request.permission='OBJECT_READ'}}
Example 5: Allowing all access for a specific user for an object pattern in a bucket:
ALLOW any-user TO manage objects IN TENANCY where all {target.bucket.name = 'test-bucket', target.object.name = '*.pdf', request.user.id='ocid1.user.oc1..exampleuniqueID'}
Pre-Authenticated Requests
Pre-authenticated requests provide a way to let users access a bucket or object without having their own credentials. For example, you can create a request that lets a user upload backups to a bucket without owning API keys. See Object Storage Pre-Authenticated Requests for details.
Object Names
Unlike other resources, objects don't have Oracle Cloud Identifiers (OCIDs). Instead, users define an object name when they upload an object.
Use the following guidelines when naming an object:
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Use from 1 to 1024 characters.
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Valid characters are letters (upper or lowercase), numbers, and characters other than line feed, carriage return, and NULL.
Important
Bucket names and object names are case-sensitive. Object Storage handles q3-field-assets.xslx and Q3-Field-Assets.XSLX as separate objects.
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Use only Unicode characters for which the UTF-8 encoding doesn't exceed 1024 bytes. Clients are responsible for URL-encoding characters.
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Avoid entering confidential information.
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Make the name unique within the bucket. Don't use the name of an existing object within the bucket when naming an object unless you intend to overwrite the existing object with the contents of the new or renamed object.
Object names can include one or more forward slash (/) characters in the name. See Object Naming Using Prefixes and Hierarchies for more information on using the forward slash in object names to create hierarchies.
Object Naming Using Prefixes and Hierarchies
Within an Object Storage namespace, buckets and objects exist in a flat structure. However, you can simulate a directory structure by adding a prefix string that includes one or more forward slashes (/) to an object name. Doing so lets you list one directory at a time, which is helpful when navigating a large set of objects.
For example:
marathon/finish_line.jpg
marathon/participants/p_21.jpg
If you added prefixes to object names, you can:
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Use the CLI or API to perform bulk downloads and bulk deletes of all objects at a specified level of the hierarchy.
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Use the Console to display a hierarchical view of your objects in virtual folders. In the previous example,
marathon
would be displayed as a folder containing an object namedfinish_line.jpg
andparticipants
would be a subfolder ofmarathon
, containing an object namedp_21.jpg
. You can bulk upload objects to any level of the hierarchy and perform bulk deletes of all the objects in a bucket or folder.
Bulk operations at a specified level of the hierarchy don't affect objects in any preceding level.
When naming objects, you can also use prefix strings without a delimiter. No delimiters
would allow search operations in the Console and certain
bulk operations in the CL or API to match on the prefix portion of the object name. For
example, in the object names below, the string gloves_27_
can serve as
a prefix for matching purposes when performing bulk operations:
gloves_27_dark_green.jpg
gloves_27_light_blue.jpg
When you perform bulk uploads with the Console, CLI, or API, you can prepend a prefix string to the names of the files you're uploading.
For hierarchy and prefix string details for a particular management interface, see the individual tasks in Object Storage Buckets.
Optional Response Headers and Metadata
When you upload objects, you can provide optional response headers and user-defined metadata. Response headers are HTTP headers sent from Object Storage to Object Storage clients when objects are downloaded. User-defined metadata are name-value pairs stored with an object. You can use the Console, REST API, or CLI to provide these optional attributes.
No validation is performed on the response headers or metadata you provide.
You can specify values for the following response headers:
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Content-Disposition
Defines presentation only information for the object. Specifying values for this header has no effect on Object Storage behavior. Programs that read the object decide what to do based on the value provided. For example, you could use this header to let users download objects with custom file names in a browser:
attachment; filename="fname.ext"
See https://tools.ietf.org/html/rfc2616#section-19.5.1 for more information.
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Cache-Control
Defines the caching behavior for the object. Specifying values for this header has no effect on Object Storage behavior. Programs that read the object decide what to do based on the value provided. For example, you could use this header to identify objects that require caching restrictions:
no-cache, no-store
See https://tools.ietf.org/html/rfc2616#section-14.9 for more information.
You specify user-defined metadata in the form of name-value pairs. User-defined metadata names are stored and returned to Object Storage clients with the mandatory prefix of opc-meta-.
Object Lifecycle Management
Object Lifecycle Management lets you automatically manage the deletion of uncommitted multipart uploads, the movement of objects to a different storage tier, and the deletion of supported resources on your behalf within a given bucket. These automated actions are based on rules that you define and manage. See Object Storage Object Lifecycle Management for more information about this feature.
Multipart Uploading and Downloading
The Oracle Cloud Infrastructure Object Storage service supports multipart uploading and downloading for objects.
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For information about the API and CLI multipart uploading functionality, see Object Storage Multipart Uploads.
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For CLI information on multipart downloading, see downloading an object using multipart download.
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For API documentation related to multipart downloading, see the GetObject API call and its range parameter.
Monitoring Resources
You can monitor the health, capacity, and performance of your Oracle Cloud Infrastructure resources by using metrics, alarms, and notifications. For more information, see Monitoring and Notifications.
For more information about monitoring objects, see Object Storage Metrics.
Creating Automation for Objects Using the Events Service
You can create automation based on state changes for your Oracle Cloud Infrastructure resources by using event types, rules, and actions. For more information, see Overview of Events.