= Osmer

Osmer is a tool to manage local OSM database: import data, transform it to convenient scheme and update it.

== Features

Importing and updating data in osm2pgsql schema (osm2pgsql required)
Custom derived schemas for analysis or rendering convenience
BBox restriction of imported data
Data reprojection between schemas
Geometry simplification
(planned) Native database schema support
(planned) Rails-like config/database.yml support for seamless integration with webapps
(planned) Importing and updating data in pgsnapshot schema (osmosis required)

== Configuration

Database schemas definition goes to Osmfile which contains basic flags and schema definitions:

prefix 'osmer' # Prefix for all tables

schema :source, :type => :osm2pgsql do # Osm2pgsql schema named 'source'

bbox 35.859375, 54.367759, 36.562495, 54.775345 # It has bounding box restriction as minlon, minlat, maxlon, maxlat

updates :daily do # It may be updated on daily basis
  dump 'http://data.gis-lab.info/osm_dump/dump/RU-KLU/RU-KLU-{today}.osm.pbf' # Where initial dump should be downloaded from here
  diff 'http://data.gis-lab.info/osm_dump/diff/RU/RU-{yesterday}-{today}.osc.gz' # And diff should be downloaded from here
end

end

schema :rendering, :projection => 900913 do # Rendering schema containing only necessary data

multipolygons :places do # Table of place boundaries
  map :place => [:city, :town, :village, :hamlet] # It contains features which have place tag with one of values: city, town, village, hamlet

  with :area # And also polygon area
end

lines :roads do # Table of roads
  map :highway # It contains features with highway tag

  with :length, :ref => :string # And also road length and ref tag to additional table column
end

end

== Usage

Osmer may be used as command-line executable with following commands:

<tt>osmer schema create [SCHEMA]</tt> # Create given osm schema in database (create all if none specified)
<tt>osmer schema drop [SCHEMA]</tt> # Drop given osm schema in database (drop all if none specified)
<tt>osmer schema recreate [SCHEMA]</tt> # Recreate given osm schema in database (recreate all if none specified)
<tt>osmer data import [SCHEMA] [FILE]</tt> # Import data to given schema from file
<tt>osmer data update [SCHEMA] [FILE]</tt> # Update data in schema from given change file

Supported options:

-c, [--config=CONFIG] Config file location, default value <tt>Osmfile</tt>
-h, [--dbhost=DBHOST] Database host, default value <tt>localhost</tt>
-p, [--dbport=DBPORT] Database port, default value <tt>5432</tt>
-U, [--dbuser=DBUSER] Database user
-P, [--dbpass=DBPASS] Database password
-d, [--dbname=DBNAME] Database name

== Details

=== Schema

Schema is a set of tables representing osm data in a common way. Examples of schemas may be:

Osm2Pgsql schema
PgSnapshot schema populated with Osmosis
Custom set of tables, representing data in convenient way

All tables in schema share common projection. In database schemas are represented with table prefixes (native schemas will be supported later)

=== Table

=== Mapper

Special mappers:

[geometry] Feature geometry - present by default, configured with <tt>simplify</tt>
[name] Feature name - present by default
[type] Feature type - present by default, configured with <tt>map</tt>
[z_order] Order of feature in rendering - specified with <tt>z_order</tt>

Available mappers (specified with <tt>with</tt>):

[string] Simple string column
[address] Address columns
[area] Polygon (or multipolygon) area
[length] Line (or multiline) length

== Internals

=== Schema

In code, schema is representd by an object, which have following methods:

create! - to create schema in database
drop! - to drop schema in database
attach_listener! - (optional) - to add listener to schema data, which may be used to have autoupdate functionality

listener with name <name> is a stored procedure set:

<name>_insert(id,*args) <name>_update(id,*args) <name>_delete(id)

=== Mapper

Mapper is represented by Ruby class which have methods:

[fields] hash in form of field-type to add to table
[assignments] hash in form of field-expression
[conditions] list of conditions on source data
[indexes] hash of indexes in form name-specification to be added

==== Advanced mapper usage

with do int :layer, :null => false, :default => 0 end

== Contributors

See https://github.com/alno/osmer/graphs/contributors

Osmer

Install / Use

README