A common julialang API for object storage
Author JockLawrie
0 Stars
Updated Last
4 Years Ago
Started In
November 2018


This package defines an abstract type, ObjectStore, and a common API for accessing object storage. This allows you to swap storage back-ends without changing your code.

Storage back-ends include in-memory, local disk and cloud-based object storage.

What is an object store?

In an object store, data is stored as objects and objects are grouped into buckets.

Concrete examples of object stores include:


An object store's access to buckets and objects is controlled using the small but flexible Authorization.jl framework. This framework allows both fine-grained access control for specific buckets and objects, as well as more coarse access control such as uniform access for all buckets and/or objects. Please read the README to understand how to access buckets and objects can be controlled.

NOTE: An ObjectStore cannot act on (create/read/delete) buckets or objects that are outside the root bucket.

Example Usage

See the examples and tests in LocalDiskObjectStores.jl and GoogleCloudObjectStores.jl, which uses the local file system as the storage back-end.


store = T(args...)  # Constructor for some T <: ObjectStore

# Set access permissions
setpermission!(store, :bucket, Permission(false, true, false, false))  # Bucket access is cRud (read-only) without expiry
setpermission!(store, :object, Permission(false, true, false, false))  # Object access is cRud (read-only) without expiry

# Allow CRUD (read/write) access for 5 minutes to objects in the bucket called "mybucket"
setpermission!(store, r"^rootbucket/mybucket/.+", Permission(true, true, true, true, now() + Minute(5)))

# Buckets
createbucket!(store, "mybucket")  # Create mybucket in the root bucket
listcontents(store,  "mybucket")  # List the contents of rootbucket/mybucket. Return nothing if it doesn't exist
deletebucket!(store, "mybucket")  # Delete rootbucket/mybucket if it exists

# Objects
store["mybucket/myobject"] = value     # Create/update. Not possible if the bucket doesn't exist.
store["mybucket/myobject"]             # Read. Returns nothing if the object doesn't exist.
delete!(store, "mybucket/myobject")

# Conveniences
isbucket(store,  bucketname)  # True if bucketname refers to a bucket
isobject(store,  objectname)  # True if objectname refers to an object

# Permission queries
p = getpermission(store, bucket_or_object)  # Get the permission settings for the specific bucket/object
setexpiry!(store, now() + Hour(1))          # Set an expiry for all the buckets/objects that the store has access to

haspermission(store, bucket_or_object, :create)  # True if the store has :create access to the bucket/object
permissions_conflict(store, "mybucket")          # True if the rules that define the store's access to "mybucket" conflict

Required Packages