Crate osmpbfreader [−] [src]
This crate provide an interface to easily read OpenStreetMap PBF files. Its main inspiration is libosmpbfreader.
# Usage
You can add osmpbfreader
to your dependencies in your project's
Cargo.toml
.
[dependencies]
osmpbfreader = "0.6"
and this to your crate root:
extern crate osmpbfreader;
# Getting objects and their dependencies
Most of the time, you'll want a subset of the OSM objects and its dependencies (i.e. the nodes inside a way, and not only the ids of the nodes of this way). For that, an easy to use function is availlable.
let path = std::path::Path::new("/dev/null"); let r = std::fs::File::open(&path).unwrap(); let mut pbf = osmpbfreader::OsmPbfReader::new(r); let objs = osmpbfreader::get_objs_and_deps(&mut pbf, |obj| { obj.way().map_or(false, |w| w.tags.contains_key("highway")) }) .unwrap(); for (id, obj) in &objs { println!("{:?}: {:?}", id, obj); }
# Readding without error handling
The easiest way to read a PBF file is to directly iterate on the
OsmObj
.
let path = std::path::Path::new("/dev/null"); let r = std::fs::File::open(&path).unwrap(); let mut pbf = osmpbfreader::OsmPbfReader::new(r); for obj in pbf.iter() { println!("{:?}", obj); }
Notice that, in case of any error, it'll panic.
# Readding with error handling
To manage error handling, a little more work is needed. First,
iteration on the different blocks is done, and then, for each
blocks, after error handling, iteration on the OsmObj
can be
done.
use std::process::exit; use osmpbfreader::blocks; let path = std::path::Path::new("/dev/null"); let r = std::fs::File::open(&path).unwrap(); let mut pbf = osmpbfreader::OsmPbfReader::new(r); for block in pbf.primitive_blocks() { // error handling: let block = block.unwrap_or_else(|e| {println!("{:?}", e); exit(1)}); for obj in blocks::iter(&block) { println!("{:?}", obj); } }
# Into the details
This crate is build around basic iterators on different parts of the structure of the PBF format. Then, several higher level iterator are proposed. It is then possible to iterate on the file using the low level iterators.
use osmpbfreader::{primitive_block_from_blob, groups}; let path = std::path::Path::new("/dev/null"); let r = std::fs::File::open(&path).unwrap(); let mut pbf = osmpbfreader::OsmPbfReader::new(r); for block in pbf.blobs().map(|b| primitive_block_from_blob(&b.unwrap())) { let block = block.unwrap(); for group in block.get_primitivegroup().iter() { for node in groups::simple_nodes(&group, &block) { println!("{:?}", node); } for node in groups::dense_nodes(&group, &block) { println!("{:?}", node); } for way in groups::ways(&group, &block) { println!("{:?}", way); } for relation in groups::relations(&group, &block) { println!("{:?}", relation); } } }
Notice that primitive_block_from_blob
can be costy as it
uncompress the blob. Using some kind of parallel map can then
improve the reading speed of the PBF file.
Reexports
pub use objects::OsmObj; |
pub use objects::Node; |
pub use objects::Way; |
pub use objects::Relation; |
pub use objects::Ref; |
pub use objects::OsmId; |
pub use objects::Tags; |
pub use error::Error; |
pub use error::Result; |
pub use reader::OsmPbfReader; |
pub use reader::primitive_block_from_blob; |
Modules
blocks | |
borrowed_iter | |
error | |
fileformat |
Generated from protobuf. |
groups | |
objects | |
osmformat |
Generated from protobuf. |
reader |
Functions
get_objs_and_deps |
This function give you the ability to find all the objects validating a predicate and all there dependencies. |