Consistent factories for GeoJSON and OGC API Features clients

[navispatial]

Currently client instances created using factory functions.

GeoJSON client:

/// A client for accessing a `GeoJSON` data resource at [location] via http(s)
/// conforming to [format].
///
/// The required [location] should refer to a web resource containing GeoJSON
/// compliant data.
///
/// When given the optional [client] is used for http requests, otherwise the
/// default client of the `package:http/http.dart` package is used.
///
/// When given [headers] are injected to http requests (however some can be
/// overridden by the feature source implementation).
///
/// When [format] is not given, then [GeoJSON] with default settings is used as
/// a default. Note that currently only GeoJSON is supported, but it's possible
/// to inject another format implementation (or with custom configuration) to
/// the default one.
BasicFeatureSource geoJsonHttpClient({
  required Uri location,
  http.Client? client,
  Map<String, String>? headers,
  TextReaderFormat<FeatureContent> format = GeoJSON.feature,
});

OGC API Features client:

/// A client for accessing `OGC API Features` compliant sources via http(s)
/// conforming to [format].
///
/// The required [endpoint] should refer to a base url of a feature service.
///
/// When given the optional [client] is used for http requests, otherwise the
/// default client of the `package:http/http.dart` package is used.
///
/// When given [headers] are injected to http requests (however some can be
/// overridden by the feature service implementation).
///
/// When [format] is not given, then [GeoJSON] with default settings is used as
/// a default. Note that currently only GeoJSON is supported, but it's possible
/// to inject another format implementation (or with custom configuration) to
/// the default one.
OGCFeatureService ogcApiFeaturesHttpClient({
  required Uri endpoint,
  http.Client? client,
  Map<String, String>? headers,
  TextReaderFormat<FeatureContent> format = GeoJSON.feature,
});

Another refers to an API endpoint by location, and another by endpoint. Choose one of these to be consistent.

Also consider similar factories as encoders / decoder on formats provider by geobase package:

GeoJsonClient.http(....);
GeoJsonClient.local(....); 
OGCAPI.features(....)

[navispatial]

Also there should be convenient helper methods to map generic Feature and FeatureCollection objects (GeoJSON data model) to domain specific data models.

[navispatial]

Implemented in geodata 0.11.0-dev.0.

The final implementation with small changes from plans above.

GeoJSON Features client:

/// A class with static factory methods to create feature sources conforming to
/// the GeoJSON format.
class GeoJSONFeatures {
  /// A client for accessing a `GeoJSON` data resource at [location] via http(s)
  /// conforming to [format].
  ///
  /// The required [location] should refer to a web resource containing GeoJSON
  /// compliant data.
  ///
  /// When given the optional [client] is used for http requests, otherwise the
  /// default client of the `package:http/http.dart` package is used.
  ///
  /// When given [headers] are injected to http requests (however some can be
  /// overridden by the feature source implementation).
  ///
  /// When [format] is not given, then [GeoJSON] with default settings is used
  /// as a default. Note that currently only GeoJSON is supported, but it's
  /// possible to inject another format implementation (or with custom
  /// configuration) to the default one.
  static BasicFeatureSource http({
    required Uri location,
    Client? client,
    Map<String, String>? headers,
    TextReaderFormat<FeatureContent> format = GeoJSON.feature,
  });

  /// A client for accessing a `GeoJSON` feature collection from any [source];
  ///
  /// The source function returns a future that fetches data from a file, a web
  /// resource or other sources. Contents must be GeoJSON compliant data.
  ///
  /// When [format] is not given, then [GeoJSON] with default settings is used
  /// as a default. Note that currently only GeoJSON is supported, but it's
  /// possible to inject another format implementation (or with custom
  /// configuration) to the default one.
  static BasicFeatureSource any(
    Future<String> Function() source, {
    TextReaderFormat<FeatureContent> format = GeoJSON.feature,
  });
}

OGC API Features client:

/// A class with static factory methods to create feature sources conforming to
/// the OGC API Features standard.
class OGCAPIFeatures {
  /// A client for accessing `OGC API Features` compliant sources via http(s)
  /// conforming to [format].
  ///
  /// The required [endpoint] should refer to a base url of a feature service.
  ///
  /// When given the optional [client] is used for http requests, otherwise the
  /// default client of the `package:http/http.dart` package is used.
  ///
  /// When given [headers] are injected to http requests (however some can be
  /// overridden by the feature service implementation).
  ///
  /// When [format] is not given, then [GeoJSON] with default settings is used
  /// as a default. Note that currently only GeoJSON is supported, but it's
  /// possible to inject another format implementation (or with custom
  /// configuration) to the default one.
  static OGCFeatureService http({
    required Uri endpoint,
    Client? client,
    Map<String, String>? headers,
    TextReaderFormat<FeatureContent> format = GeoJSON.feature,
  });
}