Fog::Backblaze

Integration library for gem fog and Backblaze B2 Cloud Storage

Installation

Add this line to your application's Gemfile:

gem 'fog-backblaze'

Or install it with gem:

gem install fog-backblaze

Usage

With CarrierWave

CarrierWave.configure do |config|
  config.fog_credentials = {
    provider: 'backblaze',
    b2_key_id: 'xxxx',
    b2_key_token: 'zzzxxxccc'
  }
  config.fog_directory = 'my-b2-bucket-name'
  config.fog_public = true
end

For now only public buckets are supported with CarrierWave

With fog library

require "fog/backblaze"

connection = Fog::Storage.new(
  provider: 'backblaze',

  # with one key (more secure)
  # get your API keys at https://secure.backblaze.com/app_keys.htm
  b2_key_id: 'xxxx',
  b2_key_token: 'zzzxxxccc'

  # full access to b2 account (less secure)
  b2_account_id: '123456',
  b2_account_token: 'aaaaabbbbbccccddddeeeeeffffff111112222223333',

  # optional, used to make some operations faster
  b2_bucket_name: 'app-test',
  b2_bucket_id: '6ec42006ec42006ec42',

  logger: Logger.new(STDOUT).tap {|l|
    l.formatter = proc {|severity, datetime, progname, msg|
      "#{severity.to_s[0]} - #{datetime.strftime("%T.%L")}: #{msg}\n"
    }
  },

  token_cache: 'file.txt'
)

Create bucket

connection.directories.create(key: 'my-b2-bucket', public: true)
# or
connection.put_bucket("my-b2-bucket", public: true)

Get Bucket

bucket = connection.directories.get('my-b2-bucket')
bucket.name # => 'my-b2-bucket'
bucket.bucket_id # => "2ee4e45855e60c1c8c4bbd48"
bucket.bucket_type # => "allPrivate"
bucket.cors_rules # => []

Delete bucket

connection.directories.new(key: 'my-b2-bucket').destroy
# or
connection.delete_bucket("my-b2-bucket")

Upload File

file = directory.files.create(
  key: 'example.html',
  body: File.open(__FILE__)
)
# or
connection.put_object("my-b2-bucket", "example.html", File.open(__FILE__))

List Files

directory.files.each do |file|
  p [directory.name, file.name]
end
# or
connection.list_objects("my-b2-bucket").json['files'] do |file_hash|
  p ["my-b2-bucket", file_hash['fileName']]
end

Read File

directory.files.new(key: 'example.html').body
# or
connection.get_object("my-b2-bucket", "example.html")

Get public URL

connection.get_public_object_url("my-b2-bucket", "example.html")

Delete File

directory.files.new(key: 'example.html').destroy
# or
connection.delete_object("my-b2-bucket", "example.html")

See example for more details

Adding b2_bucket_id

Most of internal operations requires bucketId field, to get right value, fog-backblaze will make API request. Usually applications use only one bucket and it's id never change (it may change only if we delete bucket and create new one with same name). We can eliminate this API request by setting b2_bucket_id attribute.

How to get b2_bucket_id:

p connection._get_bucket_id(bucket_name)

Token Cache

Each request requires authentication token, it comes from b2_authorize_account response.

Let's say we want to upload a files, then it will make 4 requests inernally:

  1. b2_authorize_account - valid for 24 hours
  2. b2_list_buckets - to get bucket_id value can be optimized with :b2_bucket_id field (should not change)
  3. b2_get_upload_url - valid for 24 hours
  4. Send data to URL from step 3

Results of steps 1, 2, 3 can be re-used by saving in TokenCache. It acts as general cachin interface with few predefined implementations:

  • In memory store token_cache: :memory (default)
  • JSON file store token_cache: 'file.txt'
  • Null store (will not cache anything) token_cache: false or token_cache: Fog::Backblaze::TokenCache::NullTokenCache.new
  • Create your custom, see token_cache.rb for examples