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/19813/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 19813,
    "uuid": "586ae7b2386741babc69c03a244264fd",
    "title": "ESA Greenhouse Gases Climate Change Initiative (GHG_cci): Merged SCIAMACHY and GOSAT Level 3 gridded atmospheric column-average methane (XCH4) product in Obs4MIPs format",
    "abstract": "This dataset contains satellite-derived atmospheric column-average dry-air mole fractions of methane (XCH4), and is a  Level 3 gridded product in Obs4MIPs format.  It has been derived by the Greenhouse Gases CCI (GHG_cci) project as part of the European Space Agency's (ESA's) Climate Change Initiative (CCI) programme, and was obtained from an ensemble of individual Level 2 (i.e. swath) XCH4 products, retrieved from the satellite sensors SCIAMACHY / ENVISAT and TANSO-FTS / GOSAT.   The versions of the Level 2 GHG-CCI data products used as input for this product are those of the GHG_cci \"Climate Research Data Package No. 3\" (CRDP#3).\r\n\r\nThis Level 3 Obs4MIPs XCH4 product has been specifically generated for comparisons with climate model output in the context of the CMIP5/CMIP6/IPCC experiments.",
    "keywords": "CCI, GHG, Obs4MIPS, methane, ESA",
    "publicationState": "citable",
    "dataPublishedTime": "2016-10-10T09:07:19",
    "doiPublishedTime": "2016-10-10T09:07:21",
    "updateFrequency": "",
    "status": "superseded",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/19980/?format=api",
        "dataPath": "/neodc/esacci/ghg/data/obs4mips/crdp_3/CH4/v100/",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 10461082,
        "numberOfFiles": 2,
        "fileFormat": "Data are in NetCDF format"
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/5242/?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/6023/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/18948/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/18949/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/18951/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/18952/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/18953/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/50416/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/50559/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/50561/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/89572/?format=api"
    ],
    "dataLineage": "Data were processed by the ESA CCI GHG project team and supplied to CEDA as part of the ESA CCI Open Data Portal Project",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/identifiers/9002/?format=api"
    ],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/13295/?format=api"
    ],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/12808/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/30127/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76178/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76189/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76187/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76190/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76188/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76186/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/193393/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/193394/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76179/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76191/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76239/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76240/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76241/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76242/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76243/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76244/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76245/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76246/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/76247/?format=api"
    ],
    "procedureAcquisition": null,
    "procedureCompositeProcess": null,
    "procedureComputation": null,
    "permissions": [
        {
            "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/2564/?format=api",
            "useLimitation": null,
            "accessConstraints": null,
            "accessCategory": "public",
            "accessRoles": null,
            "label": "public: None group",
            "licenceURL": "https://artefacts.ceda.ac.uk/licences/specific_licences/esacci_ghg_terms_and_conditions.pdf",
            "licenceClassifications": "any"
        }
    ],
    "discoveryKeywords": [
        {
            "ob_id": 1138,
            "name": "NDGO0003"
        }
    ]
}