Get record attendance helper

event.json

{
    "identifiers": [
        "osdi_sample_system:d91b4b2e-ae0e-4cd3-9ed7-d0ec501b0bc3",
        "foreign_system:1"
    ],
    "origin_system": "OSDI Sample System",
    "created_date": "2014-03-20T21:04:31Z",
    "modified_date": "2014-03-20T21:04:31Z",
    "name": "March 14th Rally",
    "title": "Rally for Justice",
    "description": "<p>Join us in the park to rally for justice!</p>",
    "summary": "Join us in the park to rally for justice!",
    "instructions": "<p>Bring a friend and a sign.</p>",
    "browser_url": "http://osdi-sample-system.org/events/rally-for-justice",
    "type": "open",
    "featured_image_url": "http://osdi-sample-system.org/images/rally-for-justice-banner.jpg",
    "total_accepted": 14,
    "status": "confirmed",
    "start_date": "2015-03-14T12:00:00Z",
    "end_date": "2015-03-14T14:00:00Z",
    "all_day": false,
    "guests_can_invite_others": true,
    "transparence": "opaque",
    "visibility": "public",
    "location": {
        "venue": "Lafayette Square",
        "address_lines": [
            "1564 H St NW"
        ],
        "locality": "Washington",
        "region": "DC",
        "postal_code": "20001",
        "country": "US",
        "language": "EN",
        "location": {
            "latitude": 38.9002101,
            "longitude": -77.0359252,
            "accuracy": "Rooftop"
        }
    },
    "reminders": [
        {
            "method": "email",
            "minutes": 1440
        },
        {
            "method": "sms",
            "minutes": 60
        }
    ],
    "share_url": "http://osdi-sample-system.org/events/my-event/",
    "total_shares": 345,
    "share_options": [
        {
            "facebook_share": {
                "title": "Debate watch party!",
                "description": "Come and watch the debate.",
                "image": "http://odsi-sample-system.org/images/event-share-image.jpg",
                "total_shares": 100
            },
            "twitter_share": {
                "message": "Watch the debate with @OSDI! Click here: http://osdi-sample-system.org/events/my-event/",
                "total_shares": 100
            },
            "email_share": {
                "subject": "Come watch the debate!",
                "body": "Can you watch the debate with us? Click here: http://osdi-sample-system.org/events/my-event/",
                "total_shares": 145
            }
        }
    ],
    "_links": {
        "self": {
            "href": "https://osdi-sample-system.org/api/v1/events/d91b4b2e-ae0e-4cd3-9ed7-d0ec501b0bc3"
        },
        "osdi:attendances": {
            "href": "https://osdi-sample-system.org/api/v1/events/d91b4b2e-ae0e-4cd3-9ed7-d0ec501b0bc3/attendances"
        },
        "osdi:creator": {
            "href": "https://osdi-sample-system.org/api/v1/people/65345d7d-cd24-466a-a698-4a7686ef684f"
        },
        "osdi:organizer": {
            "href": "https://osdi-sample-system.org/api/v1/people/8a625981-67a4-4457-8b55-2e30b267b2c2"
        },
        "osdi:modified_by": {
            "href": "https://osdi-sample-system.org/api/v1/people/c945d6fe-929e-11e3-a2e9-12313d316c29"
        },
        "osdi:record_attendance_helper": {
            "href": "https://osdi-sample-system.org/api/v1/events/d91b4b2e-ae0e-4cd3-9ed7-d0ec501b0bc3/record_attendance_helper"
        }
    }
}

get_record.rb

require 'json'

# finding the record attendance helper for an event
# it is assumed that you retreive a collection of OSDI events.

# sample event JSON from the OSDI spec
# http://opensupporter.github.io/osdi-docs/events.html#scenario-scenario-retrieving-an-individual-event-resource-get

event=JSON.parse(File.read('event.json'))

# find the links collection
links=event['_links']

# find the record link
record_link=links['osdi:record_attendance_helper']

# find the actual URL of the link
record_url=record_link['href']

# display link you should POST to
# https://osdi-sample-system.org/api/v1/events/d91b4b2e-ae0e-4cd3-9ed7-d0ec501b0bc3/record_attendance_helper
puts record_url