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/26712/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 26712,
    "uuid": "b8cbc75bfaa1414fa4431cff170a9e99",
    "title": "High accuracy room temperature line lists for the isotopologues of carbon dioxide",
    "abstract": "This dataset contains room temperature spectral line lists for 13 isotopologues of CO2, which have been calculated as part of the NERC (Natural Environment Research Council) funded 'High accuracy line intensity for carbon dioxide' project.   These high accuracy line lists were derived for use in remote sensing of CO2 in the atmosphere.  The dataset has been calculated from a theoretical model using the AMES potential energy surface and an accurate ab initio dipole moment surface.  Data is provided in HITRAN format.",
    "keywords": "CO2, carbon dioxide, line list",
    "publicationState": "published",
    "dataPublishedTime": "2019-03-04T13:41:18",
    "doiPublishedTime": null,
    "updateFrequency": "notPlanned",
    "status": "completed",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/26724/?format=api",
        "dataPath": "/badc/hi-acc-co2/data/zak_linelist",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 90041449,
        "numberOfFiles": 14,
        "fileFormat": "Data are in HITRAN 2004 format  (as defined in L.S. Rothman, D. Jacquemart, A. Barbe et al., \"The HITRAN 2004 molecular spectroscopic database\", Journal of Quantitative Spectroscopy and Radiative Transfer 96, 139-204 (2005).)"
    },
    "timePeriod": null,
    "geographicExtent": null,
    "nonGeographicFlag": false,
    "phenomena": [],
    "dataLineage": "Data were produced as part of the NERC funded  project 'High accuracy line intensities for carbon dioxide',  Grant Reference NE/J010316/1 and sent to the Centre for Environmental Data for Analysis for archiving.",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/12148/?format=api"
    ],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/13147/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/193358/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/112451/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/112455/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/193357/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/112453/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/112457/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/112454/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/112456/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/112452/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/112450/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/112777/?format=api"
    ],
    "procedureAcquisition": null,
    "procedureCompositeProcess": null,
    "procedureComputation": "https://api.catalogue.ceda.ac.uk/api/v2/computations/26725/?format=api",
    "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"
        }
    ]
}