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/32065/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 32065,
    "uuid": "84403d09cef3485883158f4df2989b0c",
    "title": "ESA Biomass Climate Change Initiative (Biomass_cci): Global datasets of forest above-ground biomass for the years 2010, 2017 and 2018, v2",
    "abstract": "This dataset comprises estimates of forest above-ground biomass for the years 2010, 2017 and 2018.   They are derived from a combination of Earth observation data, depending on the year, from the Copernicus Sentinel-1 mission, Envisat’s ASAR instrument and JAXA’s Advanced Land Observing Satellite (ALOS-1 and ALOS-2), along with additional information from Earth observation sources.    The data has been produced as part of the European Space Agency's (ESA's) Climate Change Initiative (CCI) programme by the Biomass CCI team.  \r\n\r\nThe data products consist of two (2) global layers that include estimates of:\r\n1) above ground biomass (AGB, unit: tons/ha i.e., Mg/ha)  (raster dataset).   This is defined as the mass, expressed as oven-dry weight of the woody parts (stem, bark, branches and twigs) of all living trees excluding stump and roots\r\n2) per-pixel estimates of above-ground biomass uncertainty expressed as the standard deviation in Mg/ha (raster dataset)\r\n\r\nThis release of the data is version 2, with data provided in both netcdf and geotiff format. The quantification of AGB changes by taking the difference of two maps is strongly discouraged due to local biases and uncertainties. Version 3 maps will ensure a more realistic representation of AGB changes.",
    "keywords": "ESA, CCI, Biomass",
    "publicationState": "citable",
    "dataPublishedTime": "2021-03-16T15:59:27",
    "doiPublishedTime": "2021-03-17T10:38:35",
    "updateFrequency": "notPlanned",
    "status": "completed",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/32123/?format=api",
        "dataPath": "/neodc/esacci/biomass/data/agb/maps/v2.0/",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 122579623645,
        "numberOfFiles": 1708,
        "fileFormat": "Data are in NetCDF and GeoTiff formats"
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/8795/?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/6021/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/6022/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/6023/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/66280/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/66281/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/66282/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/66283/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/66284/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/66285/?format=api"
    ],
    "dataLineage": "Data was created by the Biomass CCI team.",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/identifiers/10814/?format=api"
    ],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/29954/?format=api"
    ],
    "observationcollection_set": [],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/142202/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/142197/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/142198/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/142199/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/142200/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/142201/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/142203/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/142204/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/142196/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/142205/?format=api"
    ],
    "procedureAcquisition": null,
    "procedureCompositeProcess": "https://api.catalogue.ceda.ac.uk/api/v2/composites/29957/?format=api",
    "procedureComputation": null,
    "permissions": [
        {
            "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/2542/?format=api",
            "useLimitation": null,
            "accessConstraints": null,
            "accessCategory": "public",
            "accessRoles": null,
            "label": "public: None group",
            "licenceURL": "https://artefacts.ceda.ac.uk/licences/specific_licences/esacci_biomass_terms_and_conditions_v2.pdf",
            "licenceClassifications": "any"
        }
    ],
    "discoveryKeywords": [
        {
            "ob_id": 1138,
            "name": "NDGO0003"
        },
        {
            "ob_id": 1140,
            "name": "ESACCI"
        }
    ]
}