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/12911/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 12911,
    "uuid": "46ea21d4fcd1425eb538a7a3c9787e3e",
    "title": "ESA ALPHASAT: raw radio propagation measurements at 20 GHz at Bilbao, Spain",
    "abstract": "Radio propagation measurements at 20 GHz at Bilbao, Spain for the ESA funded Large Scale Assessment of KA/Q band atmospheric channel using the ALPHASAT TDP5 Propagation beacon signal.",
    "keywords": "ALPHASAT, radio propagation, ESA, 20 GHZ",
    "publicationState": "working",
    "dataPublishedTime": null,
    "doiPublishedTime": null,
    "updateFrequency": "asNeeded",
    "status": "underDevelopment",
    "result_field": null,
    "timePeriod": null,
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/693/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [],
    "dataLineage": "Data were collected by the project participants before processing and delivery to CEDA for archiving ",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/12892/?format=api"
    ],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/12893/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/49400/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/49399/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/49402/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/49401/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/49403/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/204902/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/204903/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/204904/?format=api"
    ],
    "procedureAcquisition": "https://api.catalogue.ceda.ac.uk/api/v2/acquisitions/12896/?format=api",
    "procedureCompositeProcess": null,
    "procedureComputation": null,
    "permissions": [],
    "discoveryKeywords": []
}