geobuf-explicit.proto

// each top-level message in a file is tag-prefixed (like fields) to differentiate between types
message Data {
    oneof data_type {
        fixed32 block_size = 1; // byte length of the following block (metadata + features/geometries)
        Metadata metadata = 2;

        Collection feature_collection = 3;
        Collection geometry_collection = 4;
        Collection collection_end = 5;

        Feature feature = 6;

        Geometry point = 7;
        Geometry linestring = 8;
        Geometry polygon = 9;

        Geometry multipoint = 10;
        Geometry multilinestring = 11;
        Geometry multipolygon = 12;
    }
}

message Metadata {
    uint32 version = 1; // geobuf version

    uint32 dimensions = 2; // max coordinate dimensions
    uint32 precision = 3; // number of digits after decimal point for coordinates

    repeated string keys = 4; // array of unique keys of a block
    repeated Value values = 5; // array of unique values of a block
}

message Collection {
    repeated uint32 custom_properties = 15 [packed = true]; // pairs of key/value indexes for arbitrary properties
}

message Feature {
    oneof id_type {
        string id = 1;
        sint64 int_id = 2;
    }
    repeated uint32 properties = 14 [packed = true]; // pairs of key/value indexes for feature properties
    repeated uint32 custom_properties = 15 [packed = true];
}

message Geometry {
    repeated uint32 lengths = 1 [packed = true]; // coordinate structure (lengths of parts etc.)
    repeated sint64 coords = 2 [packed = true]; // coordinates as delta-encoded integers
    repeated uint32 custom_properties = 15 [packed = true];
}

message Value {
    oneof value_type {
        string string_value = 1;
        double double_value = 2;
        uint64 unsigned_int_value = 3;
        uint64 negative_int_value = 4;
        bool bool_value = 5;
        string json_value = 6;
    }
}