Routing network from OSM - postgresql

I'm looking for some good tool to import map.osm to postgres and next create some routes which will be displayed by geoserver. I need route, with some text information about vertexes (e.g. city, address, address number, and so on...)
I found this:
osm2pgrouting - Import OSM data into pgRouting Database
osm2postgis -Import OSM data to PostGIS
osm2po - tool to convert OSM data into a routable format
osm4routing - OpenStreetMap data parser to turn them into a nodes-edges adapted for routing applications
I do not have many experiences with GIS, so how tool is the best for me? I try osm2pgrouting, but in result I have tables, which do not contains data about vertexes(only lat. and alt.) Thanks for answers.
UPDATE App Info:
I will be have web and android client where user enter text value of start and end node, and next over geoserver get wms with vertexes of entered route for example
My result from could be be some edges and nodes like this like this:
sequence_num, edge_distance, and informations about edge vertexes like osm_id, some text value, lat alt, etc...

I think you have a lot of work to do before you get to a complete solution, but here are some pointers. I suggest you break down your project into smaller chunks and ask specific questions on any bits you might get stuck on.
First, you need to import your data. Then you'll need some pre-processing / cleaning. Then you need your routing queries and, finally, a way to use the outputs (with this last part determining to some extent the previous steps).
Import OSM data
As I described in an answer to your previous question here, you can use OGR2OGR to import OSM data to Postgis. You can use other programs, as you mention above, but I guess you'll get much the same results. I think the difference between the OGR2OGR tables and the osm2postgis ones is that some of the columns in the latter appear in the other_tags column. However, the data is still there, you just need slightly different queries.
Preparing data
I'm assuming you'll use pgrouting for the routing, but whatever you use, you'll need a network suitable for routing (in short, the edges have a start and end node, and the end nodes must connect with other start nodes). Pgrouting has tools to create what you need and validate it. E.g. you create integer columns source and target and the function pgr_createtopology will populate the columns for you.
OGR2OGR gives you tables "lines", "points", "multipolygons", "multilinestrings". I suggest you read up on OSM to understand exactly what is in these tables, but, roughly speaking, the lines contain your roads and the multipolygons contain, amongst other things, buildings with e.g. addresses. The addresses are in a hstore column called "other_tags".
The lines do not contain addresses! (although they do contain street names). So, if you want to do address-to-address routing you need to do some preparation. You can skip this if you can live with the street names.
Create your network (e.g. if you're routing for cars, you'll want to
throw out pedestrian routes and so on)
Extract the desired addresses (including coordinates)
Either snap the addresses to the nearest node, or otherwise
relate the address to the nearest node
Pgrouting will return the edges in your route, so you need the above to relate back to your addresses.
Routing
Your app is going to send to your server (in an as-yet unspecified way) a pair of addresses or coordinates and you need postgis to return the route. With pgrouting, that's quite easy and there are plenty of examples out there, for example here. You will need to write queries that join the output to your address table to give you the desired output.
pgrouting creates a vertices table. You can get the nearest vertex with the following query:
select id from vertices_pgr
order by the_geom <-> st_setsrid(st_point(lon,lat),4326)
limit 1
Using the output
Using WMS from geoserver is unlikely to be a good choice - you won't have the information on individual edges without a lot of messing about. You might consider geoJSON, which can be read by e.g. OpenLayers, Leaflet, or you can manipulate in Javascript. Postgres has lots of useful functions for working with json and geojson.
Conclusion
That's quite a lot of work and probably new stuff if you have little GIS knowledge, and it, er, basically recreates what you'd get from Graphhopper! Are you sure that's not a better way to go?
If you do decide to go this (or similar) route break things down into manageable chunks! First, figure out exactly what you're trying to achieve, then work backwards from there. If you do decide to use OSM / pgrouting, then play with the data and pgrouting first so you understand how it works before trying address matching etc.

The tools you listed are only for producing data, but I think you actually need a routing engine.
Try Graphhopper: https://graphhopper.com
Using the WEB Api (more likely what you need), you don't need the import the data in your database. This is the easiest solution. You will have not control over the input openstreetmap data but this is fine if you don't have special requirements.
Import data and implement/integrate a routing engine directly in your application would be much more complicated.

Related

How to plot a JSON file generated by osrm for route optimization into an OSM map

I am a complete newbie to computation of gps, gis and all these geoinformatical stuff. First I describe my lessons learned to arrive at gps data. You can skip this and go to the last two paragraphs where I explain my problem with osrm and how to map a route onto an OSM map via qgis or similar tools.
I tried to do some route optimization for a bunch of addresses to support my son's paper deliverer job. I was able to generate a list of gps data by using the Nomatim engine that is available via geopy.geocoders. It's kind of a Travelling Salesman problem (TSP).
By using geopy's distance calculator and the or-tools from Google to Generate a shortest list recommendation. That worked well but it was only a TSP solution for air line :-(.
Then I was looking for route optimization toolkits but i struggled to get one for free. I thought osrm could be the right tool. I followed the descriptions given at Github, see here. I was able to generate a JSON file - at least I supposed that it's kind of a JSON file. But I was unable to project this back onto a map in QGis or any online tool from OSM. Can anyone help me?
The file with such JSON-like formatting:
{"code":"Ok","waypoints":[{"hint":"Jh4BgEUzI4BhAAAACwAAAKIAAABZAAAAkLAjQgpyikBay4dCWsuHQmEAAAALAAAAogAAAFkAAAArAAAAxwB4AARI3AI3AXgAWEbcAgIADwXVhXd1","location":...
Due to privacy issues I cannot post it here with any locations. Sorry for this. But does anyone have kind of a recipe / step-by-step guide what I need to do to plot it? I even have no idea how to "open" a map within qgis. You need to do this as kind of a database but this is totally new for me. I would prefer to work with an easier method to plot it.
Thanks in advance for any help.
Please follow the API documentation here. From that documentation
hint Unique internal identifier of the segment (ephemeral, not
constant over data updates) This can be used on subsequent request to
significantly speed up the query and to connect multiple services.
E.g. you can use the hint value obtained by the nearest query as hint
values for route inputs.
You can get the geometry in many ways. Widely GeoJSON is being used by developers. OSRM returns a very clean GeoJSON which can easily be used with Leaflet, Mapbox or other Map APIs. You need to send steps parameter true to get the full step by step direction. You can get the each segments of steps in legs. So call the GeoJSON within the geometries of every legs with loop. You can also get the geometry without passing the steps parameter true. For that you will get full geometry in a single GeoJSON within the routes property.

Identify crossroad nodes in openstreetmap data (.pbf)

does anybody know if there is a way I can seperate only the crossroad nodes which are included in a .pbf file? Is this clue (if a node is crossroad or not) included in this file's format?
Another option to solve your issue would be to use the new Atlas project.
As part of loading .osm.pbf files into in-memory Atlas files, it takes care of doing way sectioning on roads:
Load your pbf file into an Atlas. You will then have an Atlas object that you could save to a file and re-use.
Use the Atlas APIs to access all the intersections
In the end, each Atlas Node which is connected to more than 4 Edges on a two-way road or 2 Edges on a one way road would be a candidate if I understand your question correctly.
I'm not aware of a ready-made solution for this task, but it should still be relatively easy to do.
For parsing the .pbf file, I recommend using an existing library like Osmosis or Osmium. That way, you only need to implement the actual semantics of your use case.
The nodes themselves don't have any special attributes that mark them as crossroads. So instead, you will have to look at the ways containing the nodes.
Some considerations when implementing this:
You need to check the way's tags to find out whether it's a road. The most relevant key for that is highway. The details depend on your specific use case – for example, you need to decide whether footways, forestry tracks, driveways, ... should count.
What matters is the number of connecting way segments at a node, not the number of ways. For example, a node that is part of two ways may be a crossroads (if at least one of the ways continues beyond that node), or may not (if both ways start/end at that node).

Meaning of the spatialite scheme generated by the spatialite_osm_map tool

I used the spatialite_osm_map tool to generate a spatialite database from an .osm.pbf file. After the process was finished, a series of tables were generated in the database as shown in the image.
I noticed that there were 3 groups of tables based on the prefixes of their names: In_, pg_ and pt_. I also noticed that the rest of the name corresponded to a key defined in OpenStreetMap.
Can someone explain to me how the information is distributed in each of these groups and tables? I've searched for a site that explains the resulting schema after the conversion, but I've only found information on how to use the tool.
I think you have already identified the key points of this scheme.
It's main purpose is to offer the data from OSM in a way who could be more direct and intuitive for a GIS user. The data is splited according to OSM tags (aerialway, aeroway, amenity, etc., you can change the list of tags to be used if you don't need all of them) and according to the type of geometry (pt_* for points, ln_* for lines, and pg_* for polygons) so these tables (which could be directly seen as "layers" by a GIS user) can quickly be styled (for example in a GIS desktop application such as QGIS) with simple rules due to this simple schema (for example one can set rules like green for pg_natural, blue for ln_waterway and pg_waterway, or just click on the "pg_building" layer to toggle its visibility). That schema doesn't preserve all the objects from the OSM database, but only those requested to build the tables for the requested tags.
Contrary to the original way of storing OSM objects, with this kind of extraction you will lose the relationships between objects (for example in OSM the same node can be used, let's say, as part of the relationship describing an administrative boundary and as part of a road; here you will get a road line in ln_road and a polygon in pg_boundary but you will loose the information that they were maybe partially sharing nodes). Notably due to this last point, the weight of the OSM extractions can be relatively high compared to the original file.
So I guess that this kind of scheme (which is one amongst other existing ways to transform OSM data) offers an interesting abstraction for those who are not accustomed to the OSM schema which use Node, Way and Relation elements (eg, in OSM, buildings can be represented as closed way or as relation, here you get "simply" polygons for these various buildings).

Tiled OSM's - find the bounds of given city/state

I used the overpass api to downloaded a couple of tiled pieces of USA's map and now that I have the USA map locally, I would like to obtain the bounds of a given city (or state) without involving the API.
Should I search for certain tags, or relations? I assume I'll have to start from a node tagged (k=name, v=city_name) and (k=place, v=city), and based on it's id to find a way node.
Is my assumption correct? If yes, can you give me some directions on what should I look for once I have the node corresponding to the city?
Note. I went through the OSM wiki and studied a little bit the OSM XML format, however I was not able so far to have a whole picture of the OSM XML structure, so perhaps someone who has more experience with this can help me.
Administrative boundaries are mapped as ways or relations with a boundary=administrative tag. The boundary type is specified by an admin_level. The admin_level value for cities differs from country to country and can even include multiple values. But for most countries, admin_level values for cities range from 6 to 8 (for the US it starts even from 5). In contrast, US states have an admin_level of 4. With the help of these keys you can construct a Overpass query for specific cities/stares, or even query for all cities and states. Here is an example for Denver:
[out:json][timeout:25];
// gather results
(
way["boundary"="administrative"]["admin_level"~"6|7|8"]["name"="Denver"];
relation["boundary"="administrative"]["admin_level"~"6|7|8"]["name"="Denver"];
);
// print results
out body;
>;
out skel qt;
You can see that it will yield multiple results. Look at the place and admin_level tags to determine the importance of your results.
Alternatively you can use a geocoder as for example Nominatim. Here is an example for Denver. In contrast to Overpass API, Nominatim will weight the results by importance. It also supports multiple output formats and can return polygons (which you can use for determining the bounds). Please read about Nominatim's usage policy when using the instance at nominatim.openstreetmap.org.
And also see search engine results.

What do I need to find out council map boundaries in Australia for iPhone app?

There are probably about 600 councils in Australia. I need to work out how to create boundaries for them all within my iPhone application so that when a user is in a certain area the application will know which council the user is in.
I probably can get a lot of this information from councils, however what information would I need to ask for? Is boundary information enough? And then how should my developer use that?
Thanks,
It sounds like what you're asking about is how to define the boundary of a council. Generally the boundary of a council (or country, or any other geographic region) can be defined by an ordered series of latitude, longitude pairs which represent points on the surface of the Earth; the border is the line that connects them.
Such a series might look a bit like the following:
Region 1:
64.222, 41.135
64.161, 41.143
64.114, 41.080
...
Region 2:
64.114, 41.080
64.008, 41.090
64.008, 40.902
...
Given such a series of border points there are established algorithms for determining whether a given point is within the region (if you're curious you can read about them here). I'm not sure whether there are more efficient algorithms for determining which of several regions a point is in, but that's for your developer to figure out.
I'll answer your two questions separately:
1. Where do I get council map boundaries for Australia?
The Australian Bureau of Statistics publish this data in ESRI Shapefile and MapInfo format. The areas are known as "Local Government Areas". The 2010 data set is available at http://www.abs.gov.au/AUSSTATS/abs#.nsf/DetailsPage/1259.0.30.001July%202010?OpenDocument
2. How do I use geospatial data?
The ESRI Shapefile format can be read by pretty much every spatial data package under the sun. I have some favourites however:
On client side my favourite library is GDAL, a translator library with an X/MIT style Open Source license. It comes with C, C++, Python and C# bindings. Or if this is too heavyweight, you might prefer to directly use Shapelib, an MIT licensed C library used by GDAL.
On the server side you can't go past PostGIS. If you are sending your latitude/longitude pair to a web server, consider installing these spatial extensions for the postgresql server. You can load a shapefile into the database using the bundled shp2pgsql utilty. Then, to find the LGA your lat/lon pair fall into query the database like this:
SELECT * FROM lga2010
WHERE ST_Intersects(lga2010.the_geom,
ST_SetSRID(ST_MakePoint(your_longitude, your_latitude),4326))