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/37992/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 37992,
    "uuid": "1d58f2f5e7874e55a83ca57311dcfb9a",
    "title": "NO and NOy Abundance Data from Thermo Model 42i-Y NOY Analyzer Instrument at the Manchester Air Quality Site, 2019 onwards",
    "abstract": "Oxides of nitrogen (NO and NOy) rates measured at 7 metres above ground level by a Thermo Model 42i-Y NOY Analyzer Instrument at the Manchester Air Quality Site (MAQS) for the Integrated Research Observation System for Clean Air (OSCA) project.",
    "keywords": "OSCA, air quality, supersite, maqs, OSCA-AQ",
    "publicationState": "published",
    "dataPublishedTime": "2023-01-25T15:08:56",
    "doiPublishedTime": null,
    "updateFrequency": "monthly",
    "status": "ongoing",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/37993/?format=api",
        "dataPath": "/badc/osca/data/manchester/OSCA_MAQS_Thermo_49iY_NO-NOy",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 492458331,
        "numberOfFiles": 195,
        "fileFormat": "NetCDF and CSV format"
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/10487/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/3611/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/58082/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/58083/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65554/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65555/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65556/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65557/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65558/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65564/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65565/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65566/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65643/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65644/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65645/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65646/?format=api"
    ],
    "dataLineage": "Data are collected by the project team and transfered directly from the instrument to the computer database, before being transferred to the general database, where it is processed, averaged over minute time intervals and flagged where data is suspect. Once complete, data are uploaded to CEDA for archiving.\r\nData processing software found in: https://github.com/ncasuk/AMF_CVs/releases/tag/v1.0.0",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/37963/?format=api"
    ],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/37907/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/181287/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/181288/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/181289/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/181290/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/181291/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/181292/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/181297/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/181298/?format=api"
    ],
    "procedureAcquisition": "https://api.catalogue.ceda.ac.uk/api/v2/acquisitions/37995/?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": []
}