# osm4routing2
This project is a rewrite in rust from https://github.com/Tristramg/osm4routing
It converts an OpenStreetMap file (in the `.pbf` format) into a CSV file.
## Build
Get a rust distribution with `cargo`: https://www.rust-lang.org/en-US/downloads.html
Run `cargo install osm4routing`
You can now use `osm4routing <some_osmfile.pbf>` to generate the `nodes.csv` and `edges.csv` that represent the road network.
If you prefer running the application from the sources, and not installing it, you run
`cargo run --release -- <path_to_your_osmfile.pbf>`
The identifiers for nodes and edges are from OpenStreetMap.
The `id` property of an edge is unique, while the `osm_id` can be duplicated.
## Importing in a database
If you prefer having the files in database, you can run the very basic `import_postgres.sh` script.
It supposes that a database `osm4routing` exists (otherwise modify it to your needs).
## Using as a library
In order to use osm4routing as a library, add `osm4routing = "*"` in your `Cargo.toml` file in the `[dependencies]` section.
Use it:
```
let (nodes, edges) = osm4routing::read("some_data.osm.pbf")?;
```
If you wand to reject certain edges based on their tag, use the `Reader` (it also accepts "*" to reject every value):
```
let (nodes, edges) = osm4routing::Reader::new().reject("area", "yes").read("some_data.osm.pbf")?;
```
If you want only specific tags, use `required`; it accepts "*" if any value is accepted; if multiple conditions are given, it will accept any way that matches at least one of the values.
```
let (nodes, edges) = osm4routing::Reader::new().require("railway", "rail").read("some_data.osm.pbf")?;
```
If you need to read some tags, pass them to the `reader`:
```
let (nodes, edges) = osm4routing::Reader::new().read_tag("highway").read("some_data.osm.pbf")?;
```
If want to contract edges that come from different OpenStreetMap ways, but where there is no intersection (that can happen when the tags change, e.g. a tunnel):
```
let (nodes, edges) = osm4routing::Reader::new().merge_ways().read("some_data.osm.pbf")?;
```