osmiter 1.0.3

Library for reading OSM XML/GZ/BZ2/PBF files

osmiter

A simple library for parsing OSM data. Supports simple OSM XML files as well as OSM GZ, OSM BZ2 and OSM PBF.

Please be aware that osmiter uses Google's protobuf library, written in pure Python, which isn't particularly fast.

Example Usage

import osmiter

shop_count = 0

for feature in osmiter.iter_from_osm("some_osm_file.osm"):
    if feature["type"] == "node" and "shop" in feature["tag"]:
        shop_count += 1

print(f"this osm file containes {shop_count} shop nodes")

What is osmiter generating?

For each feature (node/way/relation) it yields a dict containing element attributes (like id, lat or timestamp) and 2 additional items: key "type" holding "node"/"way"/"relation" and key "tag" holding a dict with feature tags (this dict may be empty).

Additionally nodes will contain keys "lat" and "lon" with node coordinates, ways will contain key "nd" with a list of all node_ids references by this way, and relations contain a key "member" with a list of dicts of each member's attributes.

Almost all attributes are returned as strings with the exception for:

• id, ref, version, changeset, uid and changeset_count → int
• lat, lon → float
• open and visible → bool
• timestamp → aware datetime.datetime item.

Data validation

osmiter preforms almost no data validation, so it is possible to recieve ways with no nodes, relations with no members, empty tag values, invalid coordinates, references to non-existing items, or duplicate ids※.

However, several data assumptions are made:

1. Each feature has an id attribute.
   (※) For OSM PBF files, if an object is missing an id -1 will be assigned, per the osmformat.proto definition. This can result in multiple objects with an id equal to -1.
2. Each node has to have both lat and lon defined.
3. Every attribute defined in the table on attribute type conversion has to be convertible to its type.
   So, id == 0x1453, changeset_count == AAAAAA, ref == 12.433 or lat == 1.23E+10 will cause an exception;
   timestamp value has to be either ISO8601-compliant or epoch time represented by an integer.
4. Boolean atributes are only considered truthy if they're set to true (case-insensitive). Values 1, on, yes, ＴＲＵＥ will all evaluate to False.

Minimum requirements for each element

Bare-minimum node:

{
    "id": int,
    "type": "node",
    "lat": float,
    "lon": float,
    "tag": Dict[str, str], # May be empty
}

Bare-minimum way:

{
    "id": int,
    "type": "way",
    "tag": Dict[str, str], # May be empty
    "nd": List[int],
}

Bare-minimum relation:

{
    "id": int,
    "type": "relation",
    "tag": Dict[str, str], # May be empty
    "member": List[ dict ]
}

Example elements

See the corresponding OSM XML examples.

{
    "type": "node",
    "tag": {}
    "id": 298887269,
    "lat": 54.0901746,
    "lon": 12.2482632,
    "user": "SvenHRO",
    "uid": 46882,
    "visible": True,
    "version": 1,
    "changeset": 676636,
    "timestamp": datetime.datetime(2008, 9, 21, 21, 37, 45, tzinfo=datetime.timezone.utc)
}

{
    "type": "node",
    "tag": {"name": "Neu Broderstorf", "traffic_sign": "city_limit"},
    "id": 1831881213,
    "version": 1,
    "changeset": 12370172,
    "lat": 54.0900666,
    "lon": 12.2539381,
    "user": "lafkor",
    "uid": 75625,
    "visible": True,
    "timestamp": datetime.datetime(2012, 7, 20, 9, 43, 19, tzinfo=datetime.timezone.utc),
}

{
    "type": "way",
    "tag": {"highway": "unclassified", "name": "Pastower Straße"},
    "id": 26659127,
    "user": "Masch",
    "uid": 55988,
    "visible": True,
    "version": 5,
    "changeset": 4142606,
    "timestamp": datetime.datetime(2010, 3, 16, 11, 47, 8, tzinfo=datetime.timezone.utc),
    "nd": [292403538, 298884289, 261728686]
}

{
    "type": "relation",
    "tag": {
        "name": "Küstenbus Linie 123",
        "network": "VVW",
        "operator": "Regionalverkehr Küste",
        "ref": "123",
        "route": "bus",
        "type": "route"
    },
    "id": 56688,
    "user": "kmvar",
    "uid": 56190,
    "visible": True,
    "version": 28,
    "changeset": 6947637,
    "timestamp": datetime.datetime(2011, 1, 12, 14, 23, 49, tzinfo=datetime.timezone.utc),
    "member": [
        {"type": "node", "ref": 294942404, "role": ""},
        {"type": "node", "ref": 364933006, "role": ""},
        {"type": "way", "ref": 4579143, "role": ""},
        {"type": "node", "ref": 249673494, "role": ""},
    ]
}

License

osmiter is provided under the MIT license, included in the license.md file.