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/759/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 759,
    "uuid": "b047b11aec75c15f38419f046755872d",
    "title": "BAS Ion Chromatograph analysis data at Halley Bay Station for the CHABLIS Campaign (2004)",
    "abstract": "Chemistry of the Antarctic Boundary Layer and the Interface with Snow (CHABLIS) is a Natural Environment Research Council (NERC) and Antarctic Funding Initiative (AFI) funded project, aimed at studying the chemistry of the Antarctic Boundary Layer in greater detail, and for a longer duration, than has previously been attempted. Field measurements were carried out at the British Antarctic Survey station, Halley, at the Clean Air Sector Laboratory (CASLab). Year-round measurements began in February 2004, and a summer campaign focussing on oxidants ran during January/February 2005, after which CHABLIS fieldwork ended. The dataset contains Ion Chromatograph analysis data (major ions from Cascade Impactor sampling, from high volume air sampling (HIVOL) and low volume air sampling (LOVOL)  at Halley). Access to this dataset is now public.",
    "keywords": "CHABLIS, NERC, Antarctic, boundary layer, ions",
    "publicationState": "published",
    "dataPublishedTime": "2007-02-23T01:09:13",
    "doiPublishedTime": null,
    "updateFrequency": "notPlanned",
    "status": "completed",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/760/?format=api",
        "dataPath": "/badc/chablis/data/bas-filters",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 43924,
        "numberOfFiles": 4,
        "fileFormat": "NASA-Ames"
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/3681/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/9/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/54743/?format=api"
    ],
    "dataLineage": "Data files submitted as is by the CHABLIS campaign participants in 2005/2006 and archived at the BADC.",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/identifiers/504/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/identifiers/8663/?format=api"
    ],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/718/?format=api"
    ],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/715/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2325/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2323/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2326/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2346/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2327/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2328/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2324/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2332/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/54631/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/2343/?format=api"
    ],
    "procedureAcquisition": "https://api.catalogue.ceda.ac.uk/api/v2/acquisitions/762/?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"
        }
    ]
}