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/13285/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 13285,
    "uuid": "b3d30ea8969945f68383dfef511b2d78",
    "title": "ESA Cloud Climate Change Initiative (Cloud CCI): L3U cloud properties from AVHRR on NOAA 18, Version 1.0",
    "abstract": "Cloud properties derived from the AVHRR instrument on NOAA-18 by the ESA Cloud CCI project.   The L3U datasets consists of cloud properties from L2 data granules remapped to a global space grid of 0.1 degree in latitiude and longitude, without combining any observations from overlapping orbits; only sampling is done. Common notations for this processing level are also L2b and L2G.   Data is provided with a temporal resolution of 1 day.\r\n\r\nThis dataset is version 1.0 data from Phase 1 of the CCI project.",
    "keywords": "ESA, CCI",
    "publicationState": "removed",
    "dataPublishedTime": "2016-01-12T15:55:40",
    "doiPublishedTime": null,
    "updateFrequency": "",
    "status": "superseded",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/36845/?format=api",
        "dataPath": "/neodc/esacci/cloud/data/phase-1/L3U/avhrr_noaa-18/",
        "oldDataPath": [
            "https://api.catalogue.ceda.ac.uk/api/v2/results/13286/?format=api"
        ],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 1045,
        "numberOfFiles": 1,
        "fileFormat": "Data are netCDF formatted."
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/3600/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/529/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/25845/?format=api"
    ],
    "dataLineage": "Data were processed by the ESA CCI Cloud project team and supplied to CEDA in the context of the ESA CCI Open Data Portal Project.",
    "removedDataTime": "2017-06-20T00:00:00",
    "removedDataReason": "These data were removed for the following reason: Data was removed at the request of the data producer. A newer version of the data has been produced.",
    "language": "English",
    "identifier_set": [],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/13339/?format=api"
    ],
    "observationcollection_set": [],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50901/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50835/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50834/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50833/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/104855/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/105061/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/105248/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/54146/?format=api"
    ],
    "procedureAcquisition": "https://api.catalogue.ceda.ac.uk/api/v2/acquisitions/8453/?format=api",
    "procedureCompositeProcess": null,
    "procedureComputation": null,
    "permissions": [
        {
            "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/2524/?format=api",
            "useLimitation": null,
            "accessConstraints": null,
            "accessCategory": "public",
            "accessRoles": null,
            "label": "public: None group",
            "licenceURL": "https://artefacts.ceda.ac.uk/licences/specific_licences/esacci_cloud_terms_and_conditions.pdf",
            "licenceClassifications": "any"
        }
    ],
    "discoveryKeywords": [
        {
            "ob_id": 1138,
            "name": "NDGO0003"
        }
    ]
}