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/33431/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 33431,
    "uuid": "eac7485cce194194b6731cb41ae463b5",
    "title": "JNCC Sentinel-1 indices Analysis Ready Data (ARD) Radar Vegetation Index (RVIv)",
    "abstract": "These data have been created by the Joint Nature Conservation Committee (JNCC) as part of a Defra NCEA project to produce a regional, and ultimately national, system for detecting a change in habitat conditions at a land parcel level. The first stage of the project is focused on Yorkshire, UK, and therefore the dataset includes granules and scenes covering Yorkshire and surrounding areas only. The dataset contains the following indices derived from Defra and JNCC Sentinel-1 Analysis Ready Data.\r\n\r\nRVI and RVIv files are generated for Sentinel-1 orbit 132 (ascending) every 12 days. \r\n\r\nIndices have been generated using the Defra and JNCC Sentinel-1 and Sentinel-2 ARD for the granules and scenes described above. As the project continues, JNCC will expand the geographical coverage of this dataset and will provide continuous updates as ARD becomes available.",
    "keywords": "JNCC, ARD, RVIv, Sentinel 1, EO indices, Analysis Ready Data, Sentinel",
    "publicationState": "preview",
    "dataPublishedTime": null,
    "doiPublishedTime": null,
    "updateFrequency": "",
    "status": "ongoing",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/33432/?format=api",
        "dataPath": "/neodc/sentinel_ard/indices/sentinel_1/rviv/",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 225513124,
        "numberOfFiles": 3,
        "fileFormat": "These data are provided in Cloud Optimized GeoTIFF (COG) format."
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/9176/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/2609/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [],
    "dataLineage": "Data were produced by the project team and supplied for archiving at the Centre for Environmental Data Analysis (CEDA).",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/30197/?format=api"
    ],
    "observationcollection_set": [],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/149261/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/149262/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/149263/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/149264/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/149265/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/149266/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/149267/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/149268/?format=api"
    ],
    "procedureAcquisition": null,
    "procedureCompositeProcess": null,
    "procedureComputation": null,
    "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": []
}