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/26247/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 26247,
    "uuid": "55bff4add65d489e86c195edbae8f970",
    "title": "ESA Soil Moisture Climate Change Initiative (Soil_Moisture_cci): Ancillary data used for the \"Active\", \"Passive\" and \"Combined\" products, Version 04.2",
    "abstract": "These ancillary datasets were used in the production of the \"Active\", \"Passive\" and \"Combined\" soil moisture data products, created as part of the European Space Agency's (ESA) Soil Moisture Climate Change Initiative (CCI) project. The set of ancillary datasets include datasets of Average Vegetation Optical Depth data from AMSR-E, Soil Porosity, Topographic Complexity and Wetland fraction, as well as a Land Mask.  This version of the ancillary datasets were used in the production of the v04.2 Soil Moisture CCI data.\r\n\r\nThe \"Active\" \"Passive\" and \"Combined\" soil moisture products which they were used in the development of are fusions of scatterometer and radiometer soil moisture products, derived from the AMI-WS, ASCAT, SMMR, SSM/I, TMI, AMSR-E, WindSat, AMSR2 and SMOS satellite instruments. To access these products or for further details on them please see their dataset records. Additional reference documents and information relating to them can also be found on the CCI Soil Moisture project website.\r\n\r\nSoil moisture CCI data should be cited using all three of the following references:\r\n\r\n1. Dorigo, W.A., Wagner, W., Albergel, C., Albrecht, F., Balsamo, G., Brocca, L., Chung, D., Ertl, M., Forkel, M., Gruber, A., Haas, E., Hamer, D. P. Hirschi, M., Ikonen, J., De Jeu, R. Kidd, R. Lahoz, W., Liu, Y.Y., Miralles, D., Lecomte, P. (2017). ESA CCI Soil Moisture for improved Earth system understanding: State-of-the art and future directions. In Remote Sensing of Environment, 2017, ISSN 0034-4257, https://doi.org/10.1016/j.rse.2017.07.001\r\n\r\n2. Gruber, A., Dorigo, W. A., Crow, W., Wagner W. (2017). Triple Collocation-Based Merging of Satellite Soil Moisture Retrievals. IEEE Transactions on Geoscience and Remote Sensing. PP. 1-13. 10.1109/TGRS.2017.2734070\r\n\r\n3. Liu, Y.Y., Dorigo, W.A., Parinussa, R.M., de Jeu, R.A.M. , Wagner, W., McCabe, M.F., Evans, J.P., van Dijk, A.I.J.M. (2012). Trend-preserving blending of passive and active microwave soil moisture retrievals, Remote Sensing of Environment, 123, 280-297, doi: 10.1016/j.rse.2012.03.014",
    "keywords": "ESA, Soil Moisture, CCI, Ancillary",
    "publicationState": "published",
    "dataPublishedTime": "2018-06-25T14:49:20",
    "doiPublishedTime": null,
    "updateFrequency": "notPlanned",
    "status": "superseded",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/26248/?format=api",
        "dataPath": "/neodc/esacci/soil_moisture/data/ancillary/v04.2/",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 1630198,
        "numberOfFiles": 6,
        "fileFormat": "Data are in NetCDF format"
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/7094/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/529/?format=api",
    "nonGeographicFlag": false,
    "phenomena": [
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/12066/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/52664/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/52665/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/54684/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/54685/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/54686/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/60753/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/60754/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/63533/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/63534/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/63535/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/phenomona/63536/?format=api"
    ],
    "dataLineage": "Data were processed by the ESA CCI Soil Moisture project team and transferred to CEDA for the ESA CCI Open Data Portal Project.\r\nThis dataset forms part of the v04.2 Soil Moisture dataset (doi: 10.5285/3a8a94c3fa464d68b6d70df291afd457 https://doi.org/10.5285/3a8a94c3fa464d68b6d70df291afd457)",
    "removedDataTime": null,
    "removedDataReason": "",
    "language": "English",
    "identifier_set": [],
    "projects": [
        "https://api.catalogue.ceda.ac.uk/api/v2/projects/13332/?format=api"
    ],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/26170/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/109796/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/109799/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/109794/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/109795/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/109798/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/110166/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/109793/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/109800/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/109797/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/110167/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/110168/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/110169/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/110170/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/110171/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/110172/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/110173/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/110174/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/110175/?format=api"
    ],
    "procedureAcquisition": null,
    "procedureCompositeProcess": null,
    "procedureComputation": null,
    "permissions": [
        {
            "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/2535/?format=api",
            "useLimitation": null,
            "accessConstraints": null,
            "accessCategory": "public",
            "accessRoles": null,
            "label": "public: None group",
            "licenceURL": "https://artefacts.ceda.ac.uk/licences/specific_licences/esacci_soilmoisture_terms_and_conditions.pdf",
            "licenceClassifications": "any"
        }
    ],
    "discoveryKeywords": [
        {
            "ob_id": 1138,
            "name": "NDGO0003"
        }
    ]
}