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/25879/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 25879,
    "uuid": "ec331e93d21347e6bf5fa4b9c68dbd2c",
    "title": "Climatic Research Unit CRU TS 2.1 dataset of gridded month-by-month observed climate (Jan. 1901- Dec. 2002)",
    "abstract": "CRU TS2.1: The Climatic Research Unit (CRU) Time-Series (TS) version 2.1 of gridded data of month-by-month variation in climate (Jan. 1901- Dec. 2002). \r\n\r\nThe CRU TS 2.1 dataset is comprised of 1224 monthly grids of observed climate, for the period 1901-2002, covering the global land surface at 0.5 degree resolution. There are nine climate variables available: daily mean, minimum and maximum temperature, diurnal temperature range, precipitation, wet day frequency, frost day frequency, vapour pressure and cloud cover.\r\n\r\nThe primary purpose for this dataset is to provide environmental modellers with some of the inputs they require to run their models. \r\n\r\nThe creator of this data set (Dr. T. D. Mitchell) retains full ownership rights over it. The dataset may be freely used for non-commerical scientific and educational purposes, provided it is described as CRU TS 2.1 and attributed to: Mitchell, T.D., and P.D. Jones (2005): An improved method of constructing a database of monthly climate observations and associated high resolution grids. Int. J. Climatol. 25: 693–712, DOI: 10.1002/joc.1181",
    "keywords": "IPCC-DDC, CRU TS 2.1, temperature, precipitation,  vapour pressure, cloud cover, frost days, wet days, diurnal temperature range",
    "publicationState": "published",
    "dataPublishedTime": "2022-09-14T14:40:15",
    "doiPublishedTime": null,
    "updateFrequency": "",
    "status": "completed",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/25878/?format=api",
        "dataPath": "/badc/ipcc-ddc/data/obs/cru_ts2_1/clim_10",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 408667604,
        "numberOfFiles": 1433,
        "fileFormat": "Data are TIF formatted"
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/10489/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/529/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [],
    "dataLineage": "Data provided to the Intergovernmental Panel on Climate Change Data Distribution Centre for archiving.",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [],
    "projects": [],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/5525/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/108193/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/108194/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/108195/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/108196/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/108197/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/108199/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/108200/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/108198/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/181461/?format=api"
    ],
    "procedureAcquisition": null,
    "procedureCompositeProcess": null,
    "procedureComputation": null,
    "permissions": [
        {
            "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/2655/?format=api",
            "useLimitation": null,
            "accessConstraints": null,
            "accessCategory": "public",
            "accessRoles": null,
            "label": "public: None group",
            "licenceURL": "https://creativecommons.org/licenses/by-nc-sa/4.0/",
            "licenceClassifications": "personal, academic, policy"
        }
    ],
    "discoveryKeywords": []
}