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/32598/?format=api
HTTP 200 OK
Allow: GET, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "ob_id": 32598,
    "uuid": "32274aca008b4f7799e8cea69ad3508e",
    "title": "Yucatan Peninsula and Central Mexico above ground biomass maps 2010 v5.0",
    "abstract": "This dataset  contains  the biomass maps for epoch 2: 2010 (GlobBiomass project reference year) for Yucatan peninsula and Central Mexico with a 30m spatial resolution. \r\n\r\nThe dataset contains 4 raster files corresponding to 2 areas in Mexico; the  Yucatan Peninsula AGB-MEX_Yucatan2010_v5.tif, AGB_MEX_Yucatan2010_QA_v5.tif, Central Mexico, AGBMEX_Central2010_v5.tif and AGB_MEX_Central2010_QA_v5.tif. \r\n\r\nThe maps show aboveground woody biomass in Mexican forests and were generated by combining the probabilistic outputs. from a Maximum Entropy (MaxEnt) algorithm. Field inventory plots (CONAFOR, INFyS) were used in combination with SAR (JAXA ALOS PALSAR) and optical data (NASA Landsat 7), as well as a digital elevation model (NASA SRTM).,An empirical linear regression model with AGB as dependant variable (Ln-transformed) and SAR backscatter intensity (DN values) of the HV polarization as the independent variable was fitted to estimate AGB over mangrove and other wetland vegetation\r\n\r\nFurther information can be found in the documnetation section and in a read me file archived with the data",
    "keywords": "NCEO, AGB, Mexico, Yucatan",
    "publicationState": "preview",
    "dataPublishedTime": null,
    "doiPublishedTime": null,
    "updateFrequency": "",
    "status": "completed",
    "result_field": {
        "ob_id": "https://api.catalogue.ceda.ac.uk/api/v2/observations/32599/?format=api",
        "dataPath": "/neodc/nceo_biomass_maps/data/mexico/v5.0/2010/",
        "oldDataPath": [],
        "storageLocation": "internal",
        "storageStatus": "online",
        "volume": 540158114,
        "numberOfFiles": 6,
        "fileFormat": "GeoTIFF"
    },
    "timePeriod": "https://api.catalogue.ceda.ac.uk/api/v2/times/8951/?format=api",
    "geographicExtent": "https://api.catalogue.ceda.ac.uk/api/v2/bboxes/2776/?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/5002/?format=api"
    ],
    "observationcollection_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/observationcollections/30127/?format=api"
    ],
    "responsiblepartyinfo_set": [
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/145147/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/145148/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/145149/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/145150/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/145151/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/145152/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/145153/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/145154/?format=api",
        "https://api.catalogue.ceda.ac.uk/api/v2/rpis/145155/?format=api"
    ],
    "procedureAcquisition": null,
    "procedureCompositeProcess": "https://api.catalogue.ceda.ac.uk/api/v2/composites/32596/?format=api",
    "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": [
        {
            "ob_id": 1138,
            "name": "NDGO0003"
        }
    ]
}