EZID Client

EZID API Version 2 bindings. See http://ezid.cdlib.org/doc/apidoc.html.

Gem Version Build Status

Installation

Add this line to your application's Gemfile:

gem 'ezid-client'

And then execute:

$ bundle

Or install it yourself as:

$ gem install ezid-client

Basic Resource-oriented Usage (CRUD)

See the test suite for more examples.

Create (Mint/Create)

Mint an identifier on a shoulder

>> identifier = Ezid::Identifier.create(shoulder: "ark:/99999/fk4")
I, [2014-12-04T15:06:02.428445 #86655]  INFO -- : EZID MintIdentifier -- success: ark:/99999/fk4rx9d523
I, [2014-12-04T15:06:03.249793 #86655]  INFO -- : EZID GetIdentifierMetadata -- success: ark:/99999/fk4rx9d523
=> #<Ezid::Identifier id="ark:/99999/fk4rx9d523" status="public" target="http://ezid.cdlib.org/id/ark:/99999/fk4rx9d523" created="2014-12-04 20:06:02 UTC">
>> identifier.id
=> "ark:/99999/fk4rx9d523"
>> identifier.status
=> "public"
>> identifier.target
=> "http://ezid.cdlib.org/id/ark:/99999/fk4rx9d523"

A default shoulder can be configured:

  • By environment variable (added in v0.9.1):
export EZID_DEFAULT_SHOULDER="ark:/99999/fk4"
  • By client configuration:
Ezid::Client.configure do |config|
  config.default_shoulder = "ark:/99999/fk4"
end

New identifiers will then be minted on the default shoulder when a shoulder is not specified:

>> identifier = Ezid::Identifier.create
I, [2014-12-09T11:22:34.499860 #32279]  INFO -- : EZID MintIdentifier -- success: ark:/99999/fk43f4wd4v
I, [2014-12-09T11:22:35.317181 #32279]  INFO -- : EZID GetIdentifierMetadata -- success: ark:/99999/fk43f4wd4v
=> #<Ezid::Identifier id="ark:/99999/fk43f4wd4v" status="public" target="http://ezid.cdlib.org/id/ark:/99999/fk43f4wd4v" created="2014-12-09 16:22:35 UTC">

Create a specific identifier

>> identifier = Ezid::Identifier.create(id: "ark:/99999/fk4rx9d523/12345")
I, [2014-12-09T11:21:42.077297 #32279]  INFO -- : EZID CreateIdentifier -- success: ark:/99999/fk4rx9d523/12345
I, [2014-12-09T11:21:42.808534 #32279]  INFO -- : EZID GetIdentifierMetadata -- success: ark:/99999/fk4rx9d523/12345
=> #<Ezid::Identifier id="ark:/99999/fk4rx9d523/12345" status="public" target="http://ezid.cdlib.org/id/ark:/99999/fk4rx9d523/12345" created="2014-12-09 16:21:42 UTC">

Retrieve (Get Metadata)

>> identifier = Ezid::Identifier.find("ark:/99999/fk4rx9d523")
I, [2014-12-04T15:07:00.648676 #86655]  INFO -- : EZID GetIdentifierMetadata -- success: ark:/99999/fk4rx9d523
=> #<Ezid::Identifier id="ark:/99999/fk4rx9d523" status="public" target="http://ezid.cdlib.org/id/ark:/99999/fk4rx9d523" created="2014-12-04 20:06:02 UTC">

Update (Modify)

>> identifier.target
=> "http://ezid.cdlib.org/id/ark:/99999/fk43f4wd4v"
>> identifier.target = "http://example.com"
=> "http://example.com"
>> identifier.save
I, [2014-12-09T11:24:26.321801 #32279]  INFO -- : EZID ModifyIdentifier -- success: ark:/99999/fk43f4wd4v
I, [2014-12-09T11:24:27.039288 #32279]  INFO -- : EZID GetIdentifierMetadata -- success: ark:/99999/fk43f4wd4v
=> #<Ezid::Identifier id="ark:/99999/fk43f4wd4v" status="public" target="http://example.com" created="2014-12-09 16:22:35 UTC">
>> identifier.target
=> "http://example.com"

Delete

Identifier status must be "reserved" to delete. http://ezid.cdlib.org/doc/apidoc.html#operation-delete-identifier

>> identifier = Ezid::Identifier.create(shoulder: "ark:/99999/fk4", status: "reserved")
I, [2014-12-04T15:12:39.976930 #86734]  INFO -- : EZID MintIdentifier -- success: ark:/99999/fk4n58pc0r
I, [2014-12-04T15:12:40.693256 #86734]  INFO -- : EZID GetIdentifierMetadata -- success: ark:/99999/fk4n58pc0r
=> #<Ezid::Identifier id="ark:/99999/fk4n58pc0r" status="reserved" target="http://ezid.cdlib.org/id/ark:/99999/fk4n58pc0r" created="2014-12-04 20:12:39 UTC">
>> identifier.delete
I, [2014-12-04T15:12:48.853964 #86734]  INFO -- : EZID DeleteIdentifier -- success: ark:/99999/fk4n58pc0r
=> #<Ezid::Identifier id="ark:/99999/fk4n58pc0r" DELETED>

Batch Download

Instantiate an Ezid::Client and call batch_download with hash options -- see http://ezid.cdlib.org/doc/apidoc.html#parameters. Repeated values should be given as an array value for the parameter key.

Note that, due to the asynchronous nature of this request, the response only returns the URL at which the batch will be available to download (as described in the EZID documentation). Use the notify option to specify one or more email addresses to receive notification when the download file is actually available.

Example

>> c = Ezid::Client.new
=> #<Ezid::Client connection=#<Net::HTTP ezid.cdlib.org:443 open=false> user="eziduser" session=CLOSED>
>> response = c.batch_download(format: "csv", notify: "[email protected]", column: ["_id", "_target", "_status", "_profile", "_export", "_created", "_updated"], convertTimestamps: "yes", permanence: "real", owner: "eziduser")
I, [2015-02-20T15:16:53.462660 #55850]  INFO -- : EZID BatchDownload -- success: http://ezid.cdlib.org/download/473deecb96.csv.gz
=> #<Net::HTTPOK 200 OK readbody=true>
>> response.download_url
=> "http://ezid.cdlib.org/download/da543b91a0.csv.gz"

Metadata handling

Accessors are provided to ease the use of EZID reserved metadata elements and metadata profiles:

Reserved elements can be read and written using the name of the element without the leading underscore:

>> identifier.status                 # reads "_status" element
=> "public"
>> identifier.status = "unavailable" # writes "_status" element
=> "unavailable"

Notes:

  • _crossref is an exception because crossref is also the name of a metadata profile and a special element. Use identifier._crossref to read and identifier._crossref = value to write.
  • Reserved elements which are not user-writeable do not implement writers.
  • Special readers are implemented for reserved elements having date/time values -- _created and _updated -- which convert the string time values of EZID to Ruby Time instances.

Metadata profile elements can be read and written using the name of the element, replacing the dot (".") with an underscore:

>> identifier.dc_type           # reads "dc.type" element
=> "Collection"
>> identifier.dc_type = "Image" # writes "dc.type" element
=> "Image"

Registering custom metadata elements

Custom metadata element accessors can be created by a registration process:

Ezid::Client.configure do |config|
  # register the element "custom"
  config.metadata.register_element :custom
  # register the element "dc.identifier" under the accessor :dc_identifier
  config.metadata.register_element :dc_identifier, name: "dc.identifier"
end

Setting default metadata values

Default metadata values can be set:

Ezid::Client.configure do |config|
  # set multiple defaults with a hash
  config.identifier.defaults = {status: "reserved", profile: "dc"}
  # or set individual elements
  config.identifier.defaults[:status] = "reserved"
  config.identifier.defaults[:profile] = "dc"
end

Then new identifiers will receive the defaults:

>> identifier = Ezid::Identifier.create(shoulder: "ark:/99999/fk4")
I, [2014-12-09T11:38:37.335136 #32279]  INFO -- : EZID MintIdentifier -- success: ark:/99999/fk4zs2w500
I, [2014-12-09T11:38:38.153546 #32279]  INFO -- : EZID GetIdentifierMetadata -- success: ark:/99999/fk4zs2w500
=> #<Ezid::Identifier id="ark:/99999/fk4zs2w500" status="reserved" target="http://ezid.cdlib.org/id/ark:/99999/fk4zs2w500" created="2014-12-09 16:38:38 UTC">
>> identifier.profile
=> "dc"
>> identifier.status
=> "reserved"

Authentication

Credentials can be provided in any -- or a combination -- of these ways:

  • Environment variables:
export EZID_USER="eziduser"
export EZID_PASSWORD="ezidpass"
  • Client configuration:
Ezid::Client.configure do |config|
  config.user = "eziduser"
  config.password = "ezidpass"
end
  • At client initialization (only if explicitly instantiating Ezid::Client):
client = Ezid::Client.new(user: "eziduser", password: "ezidpass")

Alternate Host and Port

By default Ezid::Client connects via SSL over port 443 to the EZID host at ezid.cdlib.org, but the host, port and SSL settings may be overridden:

  • By environment variables:
export EZID_HOST="localhost"
export EZID_PORT=8443
export EZID_USE_SSL="true"
  • Client configuration:
Ezid::Client.configure do |config|
  config.host = "localhost"
  config.port = 8443
  config.use_ssl = true
end
  • At client initialization (only if explicitly instantiating Ezid::Client):
client = Ezid::Client.new(host: "localhost", port: 80)

HTTP Timeout

The default HTTP timeout is set to 300 seconds (5 minutes). The setting can be customized:

  • By environment variable:
export EZID_TIMEOUT=600
  • Client configuration:
Ezid::Client.configure do |config|
  config.timeout = 600
end
  • At client initialization
client = Ezid::Client.new(timeout: 600)

Test Helper

If you have tests that (directly or indirectly) use ezid-client you may want to require the test helper module:

require "ezid/test_helper"

The module provides constants:

  • TEST_ARK_SHOULDER => "ark:/99999/fk4"
  • TEST_DOI_SHOULDER => "doi:10.5072/FK2"
  • TEST_USER => "apitest"
  • TEST_HOST => "ezid.cdlib.org"
  • TEST_PORT => 443

The test user password is not provided - contact EZID and configure as above - or use your own EZID credentials, since all accounts can mint/create on the test shoulders.

A convenience method ezid_test_mode! is provided to configure the client to:

  • authenticate as TEST_USER
  • use TEST_HOST as the host and TEST_PORT as the port
  • use TEST_ARK_SHOULDER as the default shoulder
  • log to the null device (instead of default STDERR)

Running the ezid-client tests

See http://ezid.cdlib.org/doc/apidoc.html#testing-the-api.

In order to run the integration tests successfully, you must supply the password for the test account "apitest" (contact EZID). To run the test suite without the integration tests, use the rake ci task.

Contributing

  1. Fork it ( https://github.com/[my-github-username]/ezid-client/fork )
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create a new Pull Request