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/30093/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 30093,
    "uuid": "0c39809848ce47bb850d8ca2045e40f2",
    "title": "Biodiversity and Land Use Impacts on Tropical Forest Ecosystem Function (BALI): Isoprene concentration measurements at Wytham Woods (UK) during the summer of 2018",
    "abstract": "This dataset contains the time series of isoprene concentrations measured at Wytham Woods in the summer of 2018 during the Wytham Isoprene iDirac Oak Tree Measurements (WIsDOM) campaign, part of the NERC funded Biodiversity and Land Use Impacts on Tropical Forest Ecosystem Function (BALI) project.\r\n\r\nIsoprene is the largest biogenic emission on the planet and impacts air composition and climate. Seasonal data is important to underpin the biosphere-atmosphere exchange. A portable gas chromatograph, the iDirac (Bolas et al., Atmos. Meas. Tech, 2020) was used to monitor isoprene for a whole growing season (May-end September) in 2018 at Wytham Woods, an ancient woodland in the UK. Measurements were collected at 4 heights across the forest canopy: at ground level (0.53 m, inlet 1), in the under storey (7.25 m, inlet 2), at the crown level (13.17 m,  inlet 3) and above the canopy (15.55 m,  inlet 4). \r\n\r\nAncillary data (air temperature and photosynthetic active radiation, or PAR) were also collected.\r\n\r\nThe WIsDOM campaign was a joint effort of Cranfield University and the University of Cambridge.",
    "keywords": "BALI, WIsDOM, isoprene",
    "publicationState": "published",
    "dataPublishedTime": "2020-02-11T12:30:12",
    "doiPublishedTime": null,
    "updateFrequency": "notPlanned",
    "status": "completed",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/30094/?format=api",
        "dataPath": "/badc/deposited2018/bali/data/wytham/isoprene/",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 5601081,
        "numberOfFiles": 7,
        "fileFormat": "Data are BADG-CSV formatted."
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/8179/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/2583/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/70666/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/70667/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/70668/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/70669/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/70670/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/70671/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/70672/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/70673/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/70674/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/70675/?format=api"
    ],
    "dataLineage": "Data were collected by the project team and delivered to the Centre for Environmental data Analysis (CEDA) for archiving.",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/26485/?format=api"
    ],
    "observationcollection_set": [],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130010/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130005/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130011/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130013/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130012/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130007/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130014/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130009/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130008/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/168901/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130015/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130006/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130016/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/130017/?format=api"
    ],
    "procedureAcquisition": "https://api.catalogue.ceda.ac.uk/api/v2/acquisitions/30098/?format=api",
    "procedureCompositeProcess": null,
    "procedureComputation": null,
    "permissions": [
        {
            "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/2526/?format=api",
            "useLimitation": null,
            "accessConstraints": null,
            "accessCategory": "public",
            "accessRoles": null,
            "label": "public: None group",
            "licenceURL": "http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
            "licenceClassifications": "any"
        }
    ],
    "discoveryKeywords": [
        {
            "ob_id": 1138,
            "name": "NDGO0003"
        }
    ]
}