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/26119/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 26119,
    "uuid": "fd2eb396a33247aa9945d61e88e63c88",
    "title": "UKCP18 Time-series Analyses of Sea Surface Elevation around the UK for 2007-2100",
    "abstract": "The data are simulated 21st century trends in the one-year return level (i.e. the location parameter) of skew surge due to simulated atmospheric storminess change only. No mean sea level  change is included. The data were produced to investigate the magnitude of this component of extreme sea level change and to  give an estimate of the minimum uncertainty in this component. To produce the data,  atmospheric storminess data from five CMIP5 models was downscaled by the Swedish Meteorological and Hydrological Institute regional climate model RCA4 and used to drive the National Oceanography Centre/Met Office storm surge model CS3. The 5 largest simulated skew surges in each year were identified and a 4-parameter joint probability distribution (including a linear trend in location parameter over time) was fitted. The data given here are the trends in the location parameter from 2007 to 2099.  By construction the scale parameter does not change and so the same trend applies to all return periods. The data covers the UK coast.\r\n\r\nFurther information on this dataset and UKCP18 can be found in the documentation section.",
    "keywords": "",
    "publicationState": "published",
    "dataPublishedTime": "2018-11-26T09:00:00",
    "doiPublishedTime": null,
    "updateFrequency": "asNeeded",
    "status": "ongoing",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/26152/?format=api",
        "dataPath": "/badc/ukcp18/data/marine-sim/skew-trend",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 418201,
        "numberOfFiles": 2,
        "fileFormat": "Data are NetCDF formatted"
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/7059/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/2212/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/7026/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/7028/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/21657/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/21658/?format=api"
    ],
    "dataLineage": "Data provided by the UK Met Office",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/26015/?format=api"
    ],
    "observationcollection_set": [],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/143636/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/111123/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/111124/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/111125/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/111127/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/110958/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/111129/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/111126/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/111128/?format=api"
    ],
    "procedureAcquisition": null,
    "procedureCompositeProcess": null,
    "procedureComputation": "https://api.catalogue.ceda.ac.uk/api/v2/computations/26153/?format=api",
    "permissions": [
        {
            "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/2522/?format=api",
            "useLimitation": null,
            "accessConstraints": null,
            "accessCategory": "registered",
            "accessRoles": null,
            "label": "registered: None group",
            "licenceURL": "http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
            "licenceClassifications": "any"
        }
    ],
    "discoveryKeywords": [
        {
            "ob_id": 1138,
            "name": "NDGO0003"
        }
    ]
}