Get a list of Observation objects.

### Available end points:

- `/observations/` - Will list all Results in the database
- `/observations.json` - Will return all Results in json format. This can
also be achieved by using the accept header. `application/json`
- `/observations/<object_id>/` - Returns Results object with that id

### Available Methods:

- `GET`
- `HEAD`

### Available filters:

- `title`
- `uuid`
- `keywords`
- `status`
- `result_field`
- `discoveryKeywords`
- `updateFrequency`
- `nonGeographicFlag`
- `publicationState`
- `permissions`

### How to use filters:

These filters can be used like django query filters using __ for related model relationships.

- `/observations/?uuid=d594d53df2612bbd89c2e0e770b5c1a0`
- `/observations/?status=completed`
- `/observations/?results_field__dataPath__startswith=/neodc/esacci`
- `/observations/?discoveryKeywords__name=ESACCI`
- `/observations/?nonGeographicFlag=True`

Filters can be stacked to build an 'AND' relationship. E.g.

- `/observations/?publicationState__in=published,citable&nonGeographicFlag=True`
- `/observations/?publicationState__in=published,citable&discoveryKeyword__name=NDGO0003`

GET /api/v2/observations/19824/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 19824,
    "uuid": "6ca85a41897244d2bc952c869091187d",
    "title": "Ditton Park Archive: radio research physical reports (1917-1927)",
    "abstract": "This dataset contains of physical reports chronicling the pioneering radio research work that was carried out at Ditton Park in Slough from 1917 to 1927.\r\n\r\nPhotographs of people, equipment and buildings relating to the work carried out at Ditton Park.\r\nThe photographs are in black and white color and date from 1898 to c.1981.\r\n\r\nIn 1920 the Department of Scientific and Industrial Research formed the Radio Research Board (which located at Ditton Park in 1924) to undertake valuable research into radio science. This was the beginning of a high-quality scientific establishment that was led by a team of enthusiastic and expert scientists including Admiral of the Fleet Sir Henry Jackson, Sir Edward Appleton, Sir Robert Watson-Watt, Robert Naismith and Reginald Leslie Smith-Rose.\r\n\r\nThe records in the archive include 1930s Appleton ionogram graphs, ionospheric recording books and correspondence between the Station and its employees working at Tromso in Norway for the 1932 International Polar Year.",
    "keywords": "Ditton Park, radio, ionogram graphs",
    "publicationState": "working",
    "dataPublishedTime": null,
    "doiPublishedTime": null,
    "updateFrequency": "notPlanned",
    "status": "completed",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/19825/?format=api",
        "dataPath": "http://www.ukssdc.ac.uk/contact.html",
        "oldDataPath": [],
        "storageLocation": "external",
        "storageStatus": "offline",
        "volume": 0,
        "numberOfFiles": 0,
        "fileFormat": "Photographs"
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/5187/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/494/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [],
    "dataLineage": "The records have been retained by the World Data Centre at the Rutherford Appleton Laboratory in Chilton, Oxfordshire since September 1979. The records previously belonged to the Appleton Laboratory at Ditton Park, Slough.",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/19808/?format=api"
    ],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/10948/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75137/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75130/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75131/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75132/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75135/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75133/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75134/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75136/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75138/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75139/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75140/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75141/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75142/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75143/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75144/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75145/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75146/?format=api"
    ],
    "procedureAcquisition": null,
    "procedureCompositeProcess": null,
    "procedureComputation": null,
    "permissions": [
        {
            "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/2528/?format=api",
            "useLimitation": null,
            "accessConstraints": null,
            "accessCategory": "public",
            "accessRoles": null,
            "label": "public: None group",
            "licenceURL": "http://creativecommons.org/licenses/by/4.0/",
            "licenceClassifications": "any"
        }
    ],
    "discoveryKeywords": []
}