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/897/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 897,
    "uuid": "4cc618df49b55f0c72c8aa08e6f2fde4",
    "title": "SOLAS: Leeds OH and HO2 measurements at Cape Verde Observatory (2009)",
    "abstract": "Data from observations made at the The Cape Verde Atmospheric Observatory (16.848N, 24.871W) which exists to advance understanding of climatically significant interactions between the atmosphere and ocean and to provide a regional focal point and long-term data. The observatory is based on Calhau Island of São Vicente, Cape Verde in the tropical Eastern North Atlantic Ocean, a region which is data poor but plays a key role in atmosphere-ocean interactions of climate-related and biogeochemical parameters including greenhouse gases. It is an open-ocean site that is representative of a region likely to be sensitive to future climate change, and is minimally influenced by local effects and intermittent continental pollution. The dataset contains mixing ratio measurements of OH and HO2 from University of Leeds.",
    "keywords": "SOLAS, Cape Verde, Chemistry",
    "publicationState": "published",
    "dataPublishedTime": "2010-10-04T12:58:22",
    "doiPublishedTime": null,
    "updateFrequency": "asNeeded",
    "status": "ongoing",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/898/?format=api",
        "dataPath": "/badc/solas/data/capeverde/leeds-fage",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 86796999,
        "numberOfFiles": 8,
        "fileFormat": "Data are NASA Ames formatted"
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/3722/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/12/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/24536/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/52522/?format=api"
    ],
    "dataLineage": "Data collected at Cape Verde Atmospheric Observatory before being transmitted back to UK where NCAS staff prepare data for archiving at BADC.",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/identifiers/622/?format=api"
    ],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/5010/?format=api"
    ],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/5007/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/872/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/11685/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2920/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2918/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2921/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2922/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2923/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2924/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2925/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2919/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/75398/?format=api"
    ],
    "procedureAcquisition": "https://api.catalogue.ceda.ac.uk/api/v2/acquisitions/899/?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"
        }
    ]
}