public StacCollection(string id,
string description,
StacExtent extent,
IDictionary <string, StacAsset> assets = null,
IEnumerable <StacLink> links = null,
string license = "proprietary")
{
this.Properties = new Dictionary <string, object>();
this.Id = id;
this.StacVersion = Versions.StacVersionList.Current;
this.Description = description;
if (links == null)
{
this.Links = new Collection <StacLink>();
}
else
{
this.Links = new Collection <StacLink>(links.ToList());
}
if (assets == null)
{
this.Assets = new Dictionary <string, StacAsset>();
}
else
{
this.Assets = new Dictionary <string, StacAsset>(assets);
}
this.Summaries = new Dictionary <string, Stac.Collection.IStacSummaryItem>();
this.StacExtensions = new SortedSet <string>();
this.License = license;
this.Keywords = new Collection <string>();
this.Extent = extent;
}
/// <summary>
/// Generate a collection corresponding to the items' dictionary. Spatial and temporal extents
/// are computed. Fields values are summarized in stats object and value sets.
/// All Items are updated with the collection id
/// </summary>
/// <param name="id">Identifier of the collection</param>
/// <param name="description">Description of the collection</param>
/// <param name="items">Dictionary of Uri, StacItem. Uri points to the StacItem destination.</param>
/// <param name="license">License of the collection</param>
/// <param name="collectionUri">Uri of the collection. If provided, the items Uri and made relative to this one.</param>
/// <param name="assets">Assets of the collection</param>
/// <returns></returns>
public static StacCollection Create(string id,
string description,
IDictionary <Uri, StacItem> items,
string license = null,
Uri collectionUri = null,
IDictionary <string, StacAsset> assets = null)
{
var collection = new StacCollection(
id,
description,
StacExtent.Create(items.Values),
assets,
items.Select(item =>
{
Uri itemUri = item.Key;
if (collectionUri != null)
{
itemUri = collectionUri.MakeRelativeUri(item.Key);
}
if (!itemUri.IsAbsoluteUri)
{
itemUri = new Uri("./" + itemUri.OriginalString, UriKind.Relative);
}
return(StacLink.CreateObjectLink(item.Value, itemUri));
}),
license);
var usedExtensions = items.SelectMany(item => item.Value.GetDeclaredExtensions());
var summaryFunctions = usedExtensions.SelectMany(ext => ext.GetSummaryFunctions())
.GroupBy(prop => prop.Key)
.ToDictionary(key => key.Key, value => value.First().Value);
summaryFunctions.Add("gsd", new SummaryFunction <double>(null, "gsd", StacPropertiesContainerExtension.CreateRangeSummaryObject <double>));
summaryFunctions.Add("platform", new SummaryFunction <string>(null, "platform", StacPropertiesContainerExtension.CreateSummaryValueSet <string>));
summaryFunctions.Add("constellation", new SummaryFunction <string>(null, "constellation", StacPropertiesContainerExtension.CreateSummaryValueSet <string>));
summaryFunctions.Add("instruments", new SummaryFunction <string>(null, "instruments", StacPropertiesContainerExtension.CreateSummaryValueSet <string>));
collection.Summaries =
items.Values.SelectMany(item => item.Properties.Where(k => summaryFunctions.Keys.Contains(k.Key)))
.GroupBy(prop => prop.Key)
.ToDictionary(key => key.Key, value =>
{
if (summaryFunctions.ContainsKey(value.Key))
{
if (summaryFunctions[value.Key].Extension != null && !collection.StacExtensions.Contains(summaryFunctions[value.Key].Extension.Identifier))
{
collection.StacExtensions.Add(summaryFunctions[value.Key].Extension.Identifier);
}
return(summaryFunctions[value.Key].Summarize(value.Select(i => i.Value)));
}
return(null);
});
return(collection);
}
public ItemCollection(string id,
string description,
List <StacItem> stacItems) : base(id,
description,
null)
{
if (stacItems != null)
{
Features = new List <StacItem>(stacItems);
Extent = StacExtent.Create(stacItems);
}
}
public void CanSerializeSentinel2Sample()
{
StacExtent extent = new StacExtent(
new StacSpatialExtent(-180, -56, 180, 83),
new StacTemporalExtent(DateTime.Parse("2015-06-23T00:00:00Z").ToUniversalTime(), null)
);
StacCollection collection = new StacCollection("COPERNICUS/S2",
"Sentinel-2 is a wide-swath, high-resolution, multi-spectral\nimaging mission supporting Copernicus Land Monitoring studies,\nincluding the monitoring of vegetation, soil and water cover,\nas well as observation of inland waterways and coastal areas.\n\nThe Sentinel-2 data contain 13 UINT16 spectral bands representing\nTOA reflectance scaled by 10000. See the [Sentinel-2 User Handbook](https://sentinel.esa.int/documents/247904/685211/Sentinel-2_User_Handbook)\nfor details. In addition, three QA bands are present where one\n(QA60) is a bitmask band with cloud mask information. For more\ndetails, [see the full explanation of how cloud masks are computed.](https://sentinel.esa.int/web/sentinel/technical-guides/sentinel-2-msi/level-1c/cloud-masks)\n\nEach Sentinel-2 product (zip archive) may contain multiple\ngranules. Each granule becomes a separate Earth Engine asset.\nEE asset ids for Sentinel-2 assets have the following format:\nCOPERNICUS/S2/20151128T002653_20151128T102149_T56MNN. Here the\nfirst numeric part represents the sensing date and time, the\nsecond numeric part represents the product generation date and\ntime, and the final 6-character string is a unique granule identifier\nindicating its UTM grid reference (see [MGRS](https://en.wikipedia.org/wiki/Military_Grid_Reference_System)).\n\nFor more details on Sentinel-2 radiometric resoltuon, [see this page](https://earth.esa.int/web/sentinel/user-guides/sentinel-2-msi/resolutions/radiometric).\n",
extent);
collection.Title = "Sentinel-2 MSI: MultiSpectral Instrument, Level-1C";
collection.Links.Add(StacLink.CreateSelfLink(new Uri("https://storage.cloud.google.com/earthengine-test/catalog/COPERNICUS_S2.json")));
collection.Links.Add(StacLink.CreateParentLink(new Uri("https://storage.cloud.google.com/earthengine-test/catalog/catalog.json")));
collection.Links.Add(StacLink.CreateRootLink(new Uri("https://storage.cloud.google.com/earthengine-test/catalog/catalog.json")));
collection.Links.Add(new StacLink(new Uri("https://scihub.copernicus.eu/twiki/pub/SciHubWebPortal/TermsConditions/Sentinel_Data_Terms_and_Conditions.pdf"), "license", "Legal notice on the use of Copernicus Sentinel Data and Service Information", null));
collection.Keywords.Add("copernicus");
collection.Keywords.Add("esa");
collection.Keywords.Add("eu");
collection.Keywords.Add("msi");
collection.Keywords.Add("radiance");
collection.Keywords.Add("sentinel");
collection.Providers.Add(new StacProvider("European Union/ESA/Copernicus",
new List <StacProviderRole>()
{
StacProviderRole.producer, StacProviderRole.licensor
})
{
Uri = new Uri("https://sentinel.esa.int/web/sentinel/user-guides/sentinel-2-msi")
});
collection.Summaries.Add("datetime",
new StacSummaryRangeObject <DateTime>(
DateTime.Parse("2015-06-23T00:00:00Z").ToUniversalTime(),
DateTime.Parse("2019-07-10T13:44:56Z").ToUniversalTime()
)
);
var platforms = new StacSummaryValueSet <string>();
platforms.Add("sentinel-2a");
platforms.Add("sentinel-2b");
collection.Summaries.Add("platform", platforms);
collection.Summaries.Add("constellation",
new StacSummaryValueSet <string>(new string[] { "sentinel-2" })
);
collection.Summaries.Add("instruments",
new StacSummaryValueSet <string>(new string[] { "msi" })
);
collection.Summaries.Add("view:off_nadir",
new StacSummaryRangeObject <double>(
0.0,
100
)
);
collection.Summaries.Add("view:sun_elevation",
new StacSummaryRangeObject <double>(
6.78,
89.9
)
);
collection.Summaries.Add("sci:citation",
new StacSummaryValueSet <string>(new string[] { "Copernicus Sentinel data [Year]" })
);
collection.Summaries.Add("gsd",
new StacSummaryValueSet <int>(new int[] {
10,
30,
60
})
);
collection.Summaries.Add("proj:epsg",
new StacSummaryValueSet <int>(new int[]
{ 32601, 32602, 32603, 32604, 32605, 32606, 32607, 32608, 32609, 32610, 32611, 32612, 32613, 32614, 32615, 32616, 32617, 32618, 32619, 32620, 32621, 32622, 32623, 32624, 32625, 32626, 32627, 32628, 32629, 32630, 32631, 32632, 32633, 32634, 32635, 32636, 32637, 32638, 32639, 32640, 32641, 32642, 32643, 32644, 32645, 32646, 32647, 32648, 32649, 32650, 32651, 32652, 32653, 32654, 32655, 32656, 32657, 32658, 32659, 32660 }
)
);
collection.Summaries.Add("eo:bands",
new StacSummaryValueSet <JObject>(new JObject[] {
new JObject {
{ "name", "B1" },
{ "common_name", "coastal" },
{ "center_wavelength", 4.439 }
},
new JObject {
{ "name", "B2" },
{ "common_name", "blue" },
{ "center_wavelength", 4.966 }
},
new JObject {
{ "name", "B3" },
{ "common_name", "green" },
{ "center_wavelength", 5.6 }
},
new JObject {
{ "name", "B4" },
{ "common_name", "red" },
{ "center_wavelength", 6.645 }
},
new JObject {
{ "name", "B5" },
{ "center_wavelength", 7.039 }
},
new JObject {
{ "name", "B6" },
{ "center_wavelength", 7.402 }
},
new JObject {
{ "name", "B7" },
{ "center_wavelength", 7.825 }
},
new JObject {
{ "name", "B8" },
{ "common_name", "nir" },
{ "center_wavelength", 8.351 }
},
new JObject {
{ "name", "B8A" },
{ "center_wavelength", 8.648 }
},
new JObject {
{ "name", "B9" },
{ "center_wavelength", 9.45 }
},
new JObject {
{ "name", "B10" },
{ "center_wavelength", 1.3735 }
},
new JObject {
{ "name", "B11" },
{ "common_name", "swir16" },
{ "center_wavelength", 1.6137 }
},
new JObject {
{ "name", "B12" },
{ "common_name", "swir22" },
{ "center_wavelength", 2.2024 }
}
})
);
var actualJson = JsonConvert.SerializeObject(collection);
ValidateJson(actualJson);
Console.WriteLine(actualJson);
var expectedJson = GetJson("Collection");
ValidateJson(expectedJson);
JsonAssert.AreEqual(expectedJson, actualJson);
}