Configuration

There are a few different configuration files used by MapProxy.

mappproxy.yaml

This is the main configuration of MapProxy. It configures all aspects of the server: Which servers should be started, where comes the data from, what should be cached, etc..

seed.yaml

This file is the configuration for the mapproxy-seed tool. See seeding documentation for more information.

develop.ini or config.ini

These are the paster configuration files that are used to start MapProxy in development or production mode. See deployment documentation for more information.

Note

The configuration changed with the 0.9.0 release and you have to update any older configuration. This is a one-time change and further versions will offer backwards-compatibility. Read the migration guide for some help.

mapproxy.yaml

The configuration uses the YAML format.

The MapProxy configuration is grouped into six sections, each configures a different aspect of MapProxy. These are the following sections:

• globals: Internals of MapProxy and default values that are used in the other configuration sections.
• services: The services MapProxy offers, e.g. WMS or TMS.
• sources: Define where MapProxy can retrieve new data.
• caches: Configure the internal caches.
• layers: Configure the layers that MapProxy offers. Each layer can consist of multiple sources and caches.
• grids: Define the grids that MapProxy uses to aligns cached images.

The order of the sections is not important, so you can organize it your way.

Note

The indentation is significant and shall only contain space characters. Tabulators are not permitted for indentation.

services

Here you can configure which services should be started. The configuration for all services is described in the Services documentation.

Here is an example:

services:
  tms:
  wms:
    md:
      title: MapProxy Example WMS
      contact:
      # [...]

layers

Here you can define all layers MapProxy should offer. Each layer configuration is a YAML dictionary. The key of each layer is also the name of the layer, i.e. the name used in WMS layers argument. If MapProxy should use the same ordering of the layers for capability responses, you should put the definitions in a list (prepend a - before the key).

layers:
  - layer1:
    title: Title of Layer 1
    sources: [cache1, source2]
  - layer2:
    title: Title of Layer 2
    sources: [cache3]

Each layer contains information about the layer and where the data comes from.

• title: Readable name of the layer, e.g WMS layer title.
• sources: A list of data sources for this layer. You can use sources defined in the sources and caches section. MapProxy will merge multiple sources from left (bottom) to right (top).

caches

Here you can configure wich sources should be cached. Available options are:

sources

A list with one or more source names. The sources needs to be defined in the sources configuration. This option is required. MapProxy will merge multiple sources before they are stored on disk.

format

The internal image format for the cache. The default is image/png.

request_format

MapProxy will try to use this format to request new tiles, if it is not set format is used. This option has no effect if the source does not support that format or the format of the source is set explicitly (see suported_format or format for sources).

link_single_color_images

If set to true, MapProxy will not store tiles that only contain a single color as a separate file. MapProxy stores these tiles only once and uses symbolic links to this file for every occurrence. This can reduce the size of your tile cache if you have larger areas with no data (e.g. water areas, areas with no roads, etc.).

Note

This feature is only available on Unix, since Windows has no support for symbolic links.

minimize_meta_requests

If set to true, MapProxy will only issue a single request to the source. This option can reduce the request latency for uncached areas (on demand caching).

By default MapProxy requests all uncached meta tiles that intersect the requested bbox. With a typical configuration it is not uncommon that a requests will trigger four requests each larger than 2000x2000 pixel. With the minimize_meta_requests option enabled, each request will trigger only one request to the source. That request will be aligned to the next tile boundaries and the tiles will be cached.

watermark

Add a watermark right into the cached tiles. The watermark is thus also present in TMS or KML requests.

text

The watermark text. Should be short.

opacity

The opacity of the watermark (from 0 transparent to 255 full opaque). Use a value between 3 and 10 for unobtrusive watermarks.

grids

You can configure one or more grids for each cache. MapProxy will create one cache for each grid.

srs: ['EPSG:4326', 'EPSG:900913']

MapProxy supports on-the-fly transformation of requests with different SRSs. So it is not required to add an extra cache for each supported SRS. For best performance only the SRS most requests are in should be used.

There is some special handling layers that need geographical and projected coordinate systems. If you set both EPSG:4326 and EPSG:900913 all requests with projected SRS will access the EPSG:900913 cache, requests with geographical SRS will use EPSG:4326.

meta_size and meta_buffer

Change the meta_size and meta_buffer of this cache. See global cache options for more details.

use_direct_from_level and use_direct_from_res

You can limit until which resolution MapProxy should cache data with these two options. Requests below the configured resolution or level will be passed to the underlying source and the results will not be stored. The resolution of use_direct_from_res should use the units of the first configured grid of this cache.

Example caches configuration

caches:
 simple:
   source: [mysource]
   grids: [mygrid]
 fullexample:
   source: [mysource, mysecondsource]
   grids: [mygrid, mygrid2]
   meta_size: [8, 8]
   meta_buffer: 256
   watermark:
     text: MapProxy
   request_format: image/tiff
   format: image/jpeg

grids

Here you can define the tile grids that MapProxy uses for the internal caching. There are multiple options to define the grid, but beware, not all are required at the same time and some combinations will result in ambiguous results.

srs

The spatial reference system used for the internal cache, written as EPSG:xxxx.

tile_size

The size of each tile. Defaults to 256x256 pixel.

tile_size: [512, 512]

res

A list with all resolutions that MapProxy should cache.

res: [1000, 500, 200, 100]

res_factor

Here you can define a factor between each resolution. It should be either a number or the term sqrt2. sqrt2 is a shorthand for a resolution factor of 1.4142, the square root of two. With this factor the resolution doubles every second level. Compared to the default factor 2 you will get another cached level between all standard levels. This is suited for free zooming in vector-based layers where the results might look to blurry/pixelated in some resolutions.

For requests with no matching cached resolution the next best resolution is used and MapProxy will transform the result.

bbox

The extent of your grid. You can use either a list or a string with the lower left and upper right coordinates. You can set the SRS of the coordinates with the bbox_srs option. If that option is not set the srs of the grid will be used.

bbox: [0, 40, 15, 55]
  or
bbox: "0,40,15,55"

bbox_srs

The SRS of the grid bbox. See above.

num_levels

The total number of cached resolution levels. Defaults to 20, except for grids with sqrt2 resolutions. This option has no effect when you set an explicit list of cache resolutions.

min_res and max_res

The the resolutions of the first and the last level.

stretch_factor

MapProxy chooses the optimal cached level for requests that do not exactly match any cached resolution. MapProxy will stretch or shrink images to the requested resolution. The stretch_factor defines the maximum factor MapProxy is allowed to stretch images. Stretched images result in better performance but will look blurry when the value is to large (> 1.2).

Example: Your MapProxy caches 10m and 5m resolutions. Requests with 9m resolution will be generated from the 10m level, requests for 8m from the 5m level.

max_shrink_factor

This factor only applies for the first level and defines the maximum factor that MapProxy will shrink images.

Example: Your MapProxy layer starts with 1km resolution. Requests with 3km resolution will get a result, requests with 5km will get a blank response.

base

With this option, you can base the grid on the options of another grid you already defined.

Defining Resolutions

There are multiple options that influence the resolutions MapProxy will use for caching: res, res_factor, min_res, max_res, num_levels and also bbox and tile_size. We describe the process MapProxy uses to build the list of all cache resolutions.

If you supply a list with resolution values in res then MapProxy will use this list and will ignore all other options.

If min_res is set then this value will be used for the first level, otherwise MapProxy will use the resolution that is needed for a single tile (tile_size) that contains the whole bbox.

If you have max_res and num_levels: The resolutions will be distributed between min_res and max_res, both resolutions included. The resolutions will be logarithmical, so you will get a constant factor between each resolution. With resolutions from 1000 to 10 and 6 levels you would get 1000, 398, 158, 63, 25, 10 (rounded here for readability).

If you have max_res and res_factor: The resolutions will be multiplied by res_factor until larger then max_res.

If you have num_levels and res_factor: The resolutions will be multiplied by res_factor for up to num_levels levels.

Example grids configuration

grids:
  localgrid:
    srs: EPSG:31467
    bbox: [5,50,10,55]
    bbox_srs: EPSG:4326
    min_res: 10000
    res_factor: sqrt2
  localgrid2:
    base: localgrid
    srs: EPSG:25832
    tile_size: [512, 512]

sources

A sources defines where MapProxy can request new data. Each source has a type and all other options are dependent to this type.

See Sources for the documentation of all available sources.

An example:

sources:
  sourcename:
    type: wms
    req:
      url: http://localhost:8080/service?
      layers: base
  anothersource:
    type: wms
    # ...

globals

Here you can define some internals of MapProxy and default values that are used in the other configuration directives.

image

Here you can define some options that affect the way MapProxy generates image results.

resampling_method

The resampling method used when results need to be rescaled or transformed. You can use one of nearest, bilinear or bicubic. Nearest is the fastest and bicubic the slowest. The results will look best with bilinear or bicubic. Bicubic enhances the contrast at edges and should be used for vector images.

With bilinear you should get about 2/3 of the nearest performance, with bicubic 1/3.

See the examples below for results of nearest, bilinear and bicubic.

jpeg_quality

An integer value from 0 to 100. Larger values result in slower performance, larger file sizes but better image quality. You should try values between 75 and 90 for good compromise between performance and quality.

cache

meta_size

MapProxy does not make a single request for every tile but will request a large meta-tile that consist of multiple tiles. meta_size defines how large a meta-tile is. A meta_size of [4, 4] will request 16 tiles in one pass. With a tile size of 256x256 this will result in 1024x1024 requests to the source WMS.

meta_buffer

MapProxy will increase the size of each meta-tile request by this number of pixels in each direction. This can solve cases where labels are cut-off at the edge of tiles.

base_dir

The base directory where all cached tiles will be stored. The path can either be absolute (e.g. /var/mapproxy/cache) or relative to the mapproxy.yaml file.

lock_dir

MapProxy uses locking to prevent multiple request for the same meta-tile. This option defines where the temporary lock files will be stored. The path can either be absolute (e.g. /tmp/lock/mapproxy) or relative to the mapproxy.yaml file.

Note

Old locks will not be removed immediately but when new locks are created. So you will always find some old lock files in this directory.

concurrent_tile_creators

This limits the number of parallel requests MapProxy will make to a source WMS. This limit is per request and not for all MapProxy requests. To limit the requests MapProxy makes to a single server use the concurrent_requests option.

Example: A request in an uncached region requires MapProxy to fetch four meta-tiles. A concurrent_tile_creators value of two allows MapProxy to make two requests to the source WMS request in parallel. The splitting of the meta tile and the encoding of the new tiles will happen in parallel to.

srs

proj_data_dir

MapProxy uses Proj4 for all coordinate transformations. If you need custom projections or need to tweak existing definitions (e.g. add towgs parameter set) you can point MapProxy yo your own set of proj4 init files. The path should contain a epsg file with the EPSG definitions.

The configured path can be absolute or relative to the mapproxy.yaml.

axis_order_ne and axis_order_ne

The axis ordering defines in which order coordinates are given, i.e. lon/lat or lat/lon. The ordering is dependent to the SRS. Most clients and servers did not respected the ordering and everyone used lon/lat ordering. With the WMS 1.3.0 specification the OGC emphasized that the axis ordering of the SRS should be used.

Here you can define the axis ordering of your SRS. This might be required for proper WMS 1.3.0 support if you use any SRS that is not in the default configuration.

By default MapProxy assumes lat/long (north/east) order for all geographic and x/y (east/north) order for all projected SRS.

You need to add the SRS name to the appropriate parameter, if that is not the case for your SRS.:

srs:
  # for North/East ordering
  axis_order_ne: ['EPSG:9999', 'EPSG:9998']
  # for East/North ordering
  axis_order_en: ['EPSG:0000', 'EPSG:0001']

If you need to override one of the default values, then you need to define both axis order options, even if one is empty.

http

Secure HTTPS Connections (HTTPS)

Note

You need Python 2.6 or the SSL module for this feature.

MapProxy supports access to HTTPS servers. Just use https instead of http when defining the URL of a source. MapProxy needs a file that contains the root and CA certificates. See the Python SSL documentation for more information about the format.

http:
  ssl_ca_certs: ./certs_file

If you want to use SSL but do not need certificate verification, then you can disable it with the ssl_no_cert_check option. You can also disable this check on a source level, see WMS source options.

http:
  ssl_no_cert_check: True

client_timeout

This defines how long MapProxy should wait for data from source servers. Increase this value if your source servers are slower.

tiles

Configuration options for the TMS/Tile service.

expires_hours

The number of hours a Tile is valid. TMS clients like web browsers will cache the tile for this time. Clients will try to refresh the tiles after that time. MapProxy supports the ETag and Last-Modified headers and will respond with the appropriate HTTP ‘304 Not modified’ response if the tile was not changed.