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/39537/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 39537,
    "uuid": "8d8613a3d67a4e76adfe94c94ede6a4f",
    "title": "Mass Concentration of the Non-Refractory Component of Ambient Aerosol Particles in Air Data from Aerosol Chemical Species Monitor (ACSM) at Manchester Air  Quality Site, 2019-present",
    "abstract": "Mass Concentration of the Nitrate, Chloride, Sulphate, Ammonium and Organic Component of Ambient Aerosol Particles in Air measured at 7 metres above ground level by an Aerosol Chemical Species Monitor (ACSM)  at the Manchester Air Quality Site (MAQS), from 2019 onwards, for the Integrated Research Observation System for Clean Air (OSCA) project.",
    "keywords": "OSCA, maqs, air quality, OSCA-AQ",
    "publicationState": "published",
    "dataPublishedTime": "2023-01-17T12:19:13",
    "doiPublishedTime": null,
    "updateFrequency": "monthly",
    "status": "ongoing",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/39538/?format=api",
        "dataPath": "/badc/osca/data/manchester/OSCA_MAQS_ACSM_non-refractory",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 31535171,
        "numberOfFiles": 210,
        "fileFormat": "NetCDF and CSV"
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/10957/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/3601/?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/65559/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65560/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65561/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65562/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/65563/?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"
    ],
    "dataLineage": "Data is transfered directly from the instrument to the computer database, before being transferred to the general database, where it is processed using the Calibration data within the ACSM data. It is then divided into monthly files and data is flagged where data is suspect. \r\nData processing software found in: https://github.com/ncasuk/AMF_CVs/releases/tag/v1.0.0\r\nData obtained from 3750 CPC for June 2019 - February 2021 and December 2021 - February 2022\r\nData obtained from 3772 CPC for February - September 2021\r\nIntercomparison between CPCs Data obtained from 3750 CPC and 3772 CPC.",
    "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/192775/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/192776/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/192772/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/192773/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/192774/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/192769/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/192770/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/192771/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/192778/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/192777/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/192779/?format=api"
    ],
    "procedureAcquisition": "https://api.catalogue.ceda.ac.uk/api/v2/acquisitions/39536/?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": []
}