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/13066/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 13066,
    "uuid": "b4b1918baf664d6da3e9507f0c57a28e",
    "title": "Snowdon Mountain Railway Global Navigation Satellite Systems (GNSS): surface meteorological and GPS data from a moving train on Snowdon, North Wales",
    "abstract": "This dataset contains Global Navigation Satellite Systems (GNSS) and meteorological data from instruments mounted on a train of the Snowdon Mountain Railway (SNTR) as it travelled up and down the mountain. \r\n\r\nThe data were collected from 28th August 2011 to 16th October 2011 (50 days). \r\n\r\nTwo instruments collected data from the summit including; Paroscientific 745 (ncl-paro-745) and Leica GS10 GNSS (ncl-leica-gnss). The ncl-leica-gnss measured dual frequency GPS and GLONASS code and carrier phase satellite to receiver measurements, whilst the ncl-paro-745 sensor recorded pressure data. \r\n",
    "keywords": "snowdon-sntr",
    "publicationState": "published",
    "dataPublishedTime": "2015-09-23T09:02:23",
    "doiPublishedTime": null,
    "updateFrequency": "notPlanned",
    "status": "completed",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/13108/?format=api",
        "dataPath": "/badc/snowdon-gnss/data/snowdon-sntr",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 736188996,
        "numberOfFiles": 91,
        "fileFormat": "Files are in RINEX format. See documents for more information. "
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/3547/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/733/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [],
    "dataLineage": "Data received from project team at University of Newcastle.",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/13057/?format=api"
    ],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/13060/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50150/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50162/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50165/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50163/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50164/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50080/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50077/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50078/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50081/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/50079/?format=api"
    ],
    "procedureAcquisition": "https://api.catalogue.ceda.ac.uk/api/v2/acquisitions/13076/?format=api",
    "procedureCompositeProcess": null,
    "procedureComputation": null,
    "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"
        }
    ]
}