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/8051/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 8051,
    "uuid": "4b0ed418e30819e4448dc89a27dc8388",
    "title": "GetMapping 2m resolution Digital Surface Model (DSM) for Scotland and Wales",
    "abstract": "A 2m resolution Digital Surface Model (DSM) for Scotland and Wales photogrammetrically derived from aerial photography by GetMapping and acquired by the Landmap project. The Joint Information Systems Committee (JISC) funded Landmap service which ran from 2001 to July 2014 collected and hosted a large amount of earth observation data for the majority of the UK, part of which was elevation data. After removal of JISC funding in 2013, the Landmap service is no longer operational, with the data now held at the NEODC. A DSM is a digital model of a terrain's surface and represents the earth's surface and includes all objects on it.\r\n\r\nWhen using these data please also add the following copyright statment: © GetMapping yyyy",
    "keywords": "Landmap, DSM",
    "publicationState": "published",
    "dataPublishedTime": "2014-08-15T10:56:40",
    "doiPublishedTime": null,
    "updateFrequency": "asNeeded",
    "status": "completed",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/8052/?format=api",
        "dataPath": "/neodc/landmap/data/elevation/dsm2",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 147515589203,
        "numberOfFiles": 49726,
        "fileFormat": "Data are img and ecw (Enhanced Compression Wavelet) formatted."
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/3405/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/175/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [],
    "dataLineage": "Data collected and prepared by the Landmap team before a copy of the data were obtained by NEODC directly from Landmap.",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/identifiers/5234/?format=api"
    ],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/8044/?format=api"
    ],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/8041/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/32840/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/32841/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/32842/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/32843/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/42015/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/32839/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/42017/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/42016/?format=api"
    ],
    "procedureAcquisition": null,
    "procedureCompositeProcess": null,
    "procedureComputation": null,
    "permissions": [
        {
            "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/2588/?format=api",
            "useLimitation": null,
            "accessConstraints": null,
            "accessCategory": "restricted",
            "accessRoles": "landmap",
            "label": "restricted: landmap group",
            "licenceURL": "https://artefacts.ceda.ac.uk/licences/specific_licences/landmap.pdf",
            "licenceClassifications": "academic, specific"
        }
    ],
    "discoveryKeywords": [
        {
            "ob_id": 1138,
            "name": "NDGO0003"
        }
    ]
}