osm - Basic Datatypes

The osm submodule contains definitions of the basic data types used throughout the library.

Native OSM Objects

Native OSM object classes are lightwight wrappers around the osmium OSM data classes. They are immutable and generally bound to the lifetime of the buffer they are saved in.

There are five classes representing the basic OSM entities.

class osmium.osm.OSMObject

This is the base class for all OSM entity classes below and contains all common attributes.

changeset

(read-only) Id of changeset where this version of the object was created.

deleted

(read-only) True if the object is no longer visible.

id

(read-only) OSM id of the object.

positive_id((OSMObject)self) → int :

Get the absolute value of the id of this object.

tags

(read-only) List of tags describing the object. See osmium.osm.TagList.

timestamp

(read-only) Date when this version has been created, returned as a datetime.datetime.

uid

(read-only) Id of the user that created this version of the object. Only this ID uniquely identifies users.

user

(read-only) Name of the user that created this version. Be aware that user names can change, so that the same user ID may appear with different names and vice versa.

user_is_anonymous((OSMObject)self) → bool :

Check if the user is anonymous. If true, the uid does not uniquely identify a single user but only the group of all anonymous users in general.

version

(read-only) Version number of the object.

visible

(read-only) True if the object is visible.

class osmium.osm.Node

Represents a single OSM node. It inherits from OSMObjects and adds a single attribute, the location.

location

The geographic coordinates of the node. See osmium.osm.Location.

replace(node, **args)

Create a mutable node replacing the properties given in the named parameters. Note that this function only creates a shallow copy which is still bound to the scope of the original object.

class osmium.osm.Way

Represents a OSM way. It inherits the attributes from OSMObjects and adds an ordered list of nodes that describes the way.

ends_have_same_id((Way)self) → bool :

True if the start and end node are exactly the same.

ends_have_same_location((Way)self) → bool :

True if the start and end node of the way are at the same location.Throws an exception if the location of one of the nodes is missing.

is_closed((Way)self) → bool :

True if the start and end node are the same (synonym for ends_have_same_id).

nodes

(read-only) Ordered list of nodes. See osmium.osm.WayNodeList.

replace(way, **args)

Create a mutable way replacing the properties given in the named parameters. Note that this function only creates a shallow copy which is still bound to the scope of the original object.

class osmium.osm.Relation

Represents a OSM relation. It inherits the attributes from OSMObjects and adds an ordered list of members.

members

(read-only) Ordered list of relation members. See osmium.osm.RelationMemberList

replace(rel, **args)

Create a mutable relation replacing the properties given in the named parameters. Note that this function only creates a shallow copy which is still bound to the scope of the original object.

class osmium.osm.Area

Areas are a special kind of meta-object representing a polygon. They can either be derived from closed ways or from relations that represent multipolygons. They also inherit the attributes of OSMObjects and in addition contain polygon geometries. Areas have their own unique id space. This is computed as the OSM id times 2 and for relations 1 is added,

from_way((Area)self) → bool :

Return true if the area was created from a way, false if it was created from a relation of multipolygon type.

inner_rings((Area)self, (OuterRing)outer_ring) → InnerRingIterator :

Return an iterator over all inner rings of the multipolygon.

is_multipolygon((Area)self) → bool :

Return true if this area is a true multipolygon, i.e. it consists of multiple outer rings.

num_rings((Area)self) → tuple :

Return a tuple with the number of outer rings and inner rings.

orig_id((Area)self) → int :

Compute the original OSM id of this object. Note that this is not necessarily unique because the object might be a way or relation which have an overlapping id space.

outer_rings((object)arg1) → object :

Return an iterator over all outer rings of the multipolygon.

class osmium.osm.Changeset

A changeset description.

bounds

(read-only) The bounding box of the area that was edited.

closed_at

(read-only) Timestamp when the changeset was finalized. May be None when the changeset is still open.

created_at

(read-only) Timestamp when the changeset was first opened.

id

(read-only) Unique ID of the changeset.

num_changes

(read-only) The total number of objects changed in this Changeset.

open

(read-only) True when the changeset is still open.

tags

(read-only) List of tags describing the changeset. See osmium.osm.TagList.

uid

(read-only) User ID of the changeset creator.

user

(read-only) Name of the user that created the changeset. Be aware that user names can change, so that the same user ID may appear with different names and vice versa.

user_is_anonymous((Changeset)self) → bool :

Check if the user anonymous. If true, the uid does not uniquely identify a single user but only the group of all anonymous users in general.

Mutable OSM Objects

The objects in osmium.osm.mutable are Python versions of the native OSM objects that can be modified. You can use these classes as a base class for your own objects or to modify objects read from a file.

class osmium.osm.mutable.OSMObject(base=None, id=None, version=None, visible=None, changeset=None, timestamp=None, uid=None, tags=None)

Mutable version of osmium.osm.OSMObject. It exposes the following attributes id, version, visible, changeset, timestamp, uid and tags. Timestamps may be strings or datetime objects. Tags can be an osmium.osm.TagList, a dict-like object or a list of tuples, where each tuple contains a (key value) string pair.

If the base parameter is given in the constructor, then the object will be initialised first from the attributes of this base object.

class osmium.osm.mutable.Node(base=None, location=None, **attrs)

The mutable version of osmium.osm.Node. It inherits all attributes from osmium.osm.mutable.OSMObject and adds a location attribute. This may either be an osmium.osm.Location or a tuple of lon/lat coordinates.

class osmium.osm.mutable.Way(base=None, nodes=None, **attrs)

The mutable version of osmium.osm.Way. It inherits all attributes from osmium.osm.mutable.OSMObject and adds a nodes attribute. This may either be and osmium.osm.NodeList or a list consisting of osmium.osm.NodeRef or simple node ids.

class osmium.osm.mutable.Relation(base=None, members=None, **attrs)

The mutable version of osmium.osm.Relation. It inherits all attributes from osmium.osm.mutable.OSMObject and adds a members attribute. This may either be an osmium.osm.RelationMemberList or a list consisting of osmium.osm.RelationMember or tuples of (type, id, role). The member type should be a single character ‘n’, ‘w’ or ‘r’.

Node Reference Lists

Line geometries in OSM are simply a sequence of nodes. To simplify processing osmium returns such node sequences using a special datatype that contains a reference to the node id and also the location geometry. The latter is only valid if the node locations have been cached by a location handler.

class osmium.osm.NodeRef

A reference to a OSM node that also caches the nodes location.

lat

(read-only) Latitude (y coordinate) as floating point number.

location

(read-only) Node coordinates as a osmium.osm.Location object.

lon

(read-only) Longitude (x coordinate) as floating point number.

ref

(read-only) Id of the referenced node.

x

(read-only) X coordinate (longitude) as a fixed-point integer.

y

(read-only) Y coordinate (latitude) as a fixed-point integer.

class osmium.osm.NodeRefList

A list of node references, implemented as an immutable sequence of osmium.osm.NodeRef. This class is normally not used directly, use one of its subclasses instead.

ends_have_same_id((NodeRefList)self) → bool :

True if the start and end node are exactly the same.

ends_have_same_location((NodeRefList)self) → bool :

True if the start and end node of the way are at the same location. Throws an exception if the location of one of the nodes is missing.

is_closed((NodeRefList)self) → bool :

True if the start and end node are the same (synonym for ends_have_same_id).

class osmium.osm.WayNodeList

List of nodes in a way. For its members see osmium.osm.NodeRefList.

class osmium.osm.OuterRing

List of nodes in an outer ring. For its members see osmium.osm.NodeRefList.

class osmium.osm.InnerRing

List of nodes in an inner ring. For its members see osmium.osm.NodeRefList.

Other OSM Entity Attributes

Some of the attributes of the OSM entities are represented with more complex classes.

class osmium.osm.Box

A bounding box around a geographic area. It is defined by an osmium.osm.Location for the bottem-left corner and an osmium.osm.Location for the top-right corner. Those locations may be invalid in which case the box is considered invalid, too.

bottom_left

(read-only) Bottom-left corner of the bounding box.

contains((Box)self, (Location)location) → bool :

Check if the given location is inside the box.

extend((Box)arg1, (Location)arg2) → Box :

Extend the box to include the given location. If the location is invalid the box remains unchanged. If the box is invalid, it will contain only the location after the operation.

extend( (Box)arg1, (Box)arg2) -> Box :

Extend the box to include the given box. If the box to be added is invalid the input box remains unchanged. If the input box is invalid, it will become equal to the box that was added.

size((Box)self) → float :

Return the size in square degrees.

top_right

(read-only) Top-right corner of the bounding box.

valid((Box)self) → bool :

Check if the box coordinates are defined and with the usual bounds.

class osmium.osm.Location

A geographic coordinate in WGS84 projection. A location doesn’t necessarily have to be valid.

lat

(read-only) Latitude (y coordinate) as floating point number.

lat_without_check((Location)self) → float :

Return latitude (y coordinate) without checking if the location is valid.

lon

(read-only) Longitude (x coordinate) as floating point number.

lon_without_check((Location)self) → float :

Return longitude (x coordinate) without checking if the location is valid.

valid((Location)self) → bool :

Check that the location is a valid WGS84 coordinate, i.e. that it is within the usual bounds.

x

(read-only) X coordinate (longitude) as a fixed-point integer.

y

(read-only) Y coordinate (latitude) as a fixed-point integer.

class osmium.osm.RelationMember

Member of a relation.

ref

OSM ID of the object. Only unique within the type.

role

The role of the member within the relation, a free-text string. If no role is set then the string is empty.

type

Type of object referenced, a node, way or relation.

class osmium.osm.RelationMemberList

An immutable sequence of relation members osmium.osm.RelationMember.

class osmium.osm.Tag

A single OSM tag.

k

(read-only) Tag key.

v

(read-only) Tag value.

class osmium.osm.TagList

A fixed list of tags. The list is exported as an unmutable, dictionary-like object where the keys are tag strings and the items are osmium.osm.Tag.

get((TagList)self, (str)key, (str)default) → str

get( (TagList)arg1, (str)arg2) -> str