Configuration

There are two 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.

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 Wikipedia contains a good introduction to YAML.

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. The layer definition is similar to WMS: each layer can have a name and title and you can nest layers to build a layer tree.

Layers should be configured as a list (- in YAML), where each layer configuration is a dictionary (key: value in YAML)

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

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

name

The name of the layer. You can omit the name for group layers (e.g. layers with layers), in this case the layer is not addressable in WMS and used only for grouping.

Changed in version 0.9.1.

The old syntax to configure each layer as a dictionary with the key as the name is deprecated but still supported.

- mylayer:
   title: My Layer
   source: [mysoruce]

should become

- name: mylayer
  title: My Layer
  source: [mysoruce]

title

Readable name of the layer, e.g WMS layer title.

layers

New in version 0.9.1.

Each layer can contain another layers configuration. You can use this to build group layers and to build a nested layer tree.

For example:

layers:
  - name: root
    title: Root Layer
    layers:
      - name: layer1
        title: Title of Layer 1
        layers:
          - name: layer1a
            title: Title of Layer 1a
            sources: [source1a]
          - name: layer1b
            title: Title of Layer 1b
            sources: [source1b]
      - name: layer2
        title: Title of Layer 2
        sources: [cache2]

root and layer1 is a group layer in this case. The WMS service will render layer1a and layer1b if you request layer1. Note that sources is optional if you supply layers. You can still configure sources for group layers. In this case the group sources will replace the sources of the child layers.

MapProxy will wrap all layers into an unnamed root layer, if you define multiple layers on the first level.

Note

The old syntax (see name above) is not supported if you use the nested layer configuration format.

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).

WMS and Mapserver sources also support tagged names (wms:lyr1,lyr2). See Tagged source names.

min_res, max_res or min_scale, max_scale

Limit the layer to the given min and max resolution or scale. MapProxy will return a blank image for requests outside of these boundaries. You can use either the resolution or the scale values, missing values will be interpreted as unlimited. Resolutions should be in meters per pixel.

The values will also apear in the capabilities documents (i.e. WMS ScaleHint and Min/MaxScaleDenominator).

Pleas read scale vs. resolution for some notes on scale.

legendurl

Configure a URL to an image that should be returned as the legend for this layer. Local URLs (file://) are also supported. MapProxy ignores the legends from the sources of this layer if you configure a legendurl here.

caches

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

sources

A list with source names. The sources needs to be defined in the sources configuration. This parameter is required. MapProxy will merge multiple sources from left (bottom) to right (top) before they are stored on disk.

WMS and Mapserver sources also support tagged names (wms:lyr1,lyr2). See Tagged source names.

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).

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 30 and 100 for unobtrusive watermarks.
font_size
Font size of the watermark text.
color
Color of the watermark text. Default is grey which works good for vector images. Can be either a list of color values ([255, 255, 255]) or a hex string (#ffffff).
spacing
Configure the spacing between repeated watermarks. By default the watermark will be placed on every tile, with wide the watermark will be placed on every second tile.

New in version 1.0.0: spacing

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.

image

See below for all image options.

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. This takes only effect when used in WMS services.

disable_storage

New in version 1.0.0.

If set to true, MapProxy will not store any tiles for this cache. MapProxy will re-request all required tiles for each incoming request, even if the there are matching tiles in the cache. See seed_only if you need an offline mode.

Note

Be careful when using a cache with disabled storage in tile services when the cache uses WMS sources with metatiling.

cache_dir

Directory where MapProxy should store tiles for this cache. Uses the value of globals.cache.base_dir by default.

cache

New in version 1.2.0.

Configure the type of the background tile cache. You configure the type with the type option. The default type is file and you can leave out the cache option if you want to use the file cache. Read Caches for a detailed list of all available cache backends.

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
   origin: ul
   cache:
     type: file
     directory_layout: tms

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.

threshold_res

A list with resolutions at which MapProxy should switch from one level to another. MapProxy automatically tries to determine the optimal cache level for each request. You can tweak the behavior with the stretch_factor option (see below).

If you need explicit transitions from one level to another at fixed resolutions, then you can use the threshold_res option to define these resolutions. You only need to define the explicit transitions.

Example: You are caching at 1000, 500 and 200m/px resolutions and you are required to display the 1000m/px level for requests with lower than 700m/px resolutions and the 500m/px level for requests with higher resolutions. You can define that transition as follows:

res: [1000, 500, 200]
threshold_res: [700]

Requests with 1500, 1000 or 701m/px resolution will use the first level, requests with 700 or 500m/px will use the second level. All other transitions (between 500 an 200m/px in this case) will be calculated automatically with the stretch_factor (about 416m/px in this case with a default configuration).

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.

origin

New in version 1.3.0.

The default origin (x=0, y=0) of the tile grid is the lower left corner, similar to TMS. WMTS defines the tile origin in the upper left corner. MapProxy can translate between services and caches with different tile origins, but there are some limitations for grids with custom BBOX and resolutions that are not of factor 2. You can only use one service in these cases and need to use the matching origin for that service.

The following values are supported:

ll or sw:

If the x=0, y=0 tile is in the lower-left/south-west corner of the tile grid. This is the default.

ul or nw:

If the x=0, y=0 tile is in the upper-left/north-west corner of the tile grid.

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:

nearest:

_images/nearest.png

bilinear:

_images/bilinear.png

bicubic:

_images/bicubic.png
paletted
Enable paletted (8bit) PNG images. It defaults to true for backwards compatibility. You should set this to false if you need 24bit PNG files. You can enable 8bit PNGs for single caches with a custom format (colors: 256).
formats
Modify existing or define new image formats. See blow for all image format options.

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.

Note

Defaults to ../var/cache_data but this will be changed with 1.2.0. You should configure this value for production use.

lock_dir

MapProxy uses locking to limit multiple request to the same service. See concurrent_requests. 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

Defaults to ../tmp/tile_locks but this will be changed with 1.2.0. You should configure this value for production use.

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 to your own set of proj4 init files. The path should contain an epsg file with the EPSG definitions.

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

axis_order_ne and axis_order_en

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

HTTP related options.

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. If the server certificate is signed by a “standard” root certificate (i.e. your browser does not warn you), then you can use a cert file that is distributed with your system. On Debian based systems you can use /etc/ssl/certs/ca-certificates.crt. See the Python SSL documentation for more information about the format.

http:
  ssl_ca_certs: /etc/ssl/certs/ca-certificates.crt

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.

method

Configure which HTTP method should be used for HTTP requests. By default (AUTO) MapProxy will use GET for most requests, except for requests with a long query string (e.g. WMS requests with sld_body) where POST is used instead. You can disable this behavior with either GET or POST.

http:
  method: GET

headers

New in version 1.0.0.

Add additional HTTP headers to all requests to your sources.

http:
  headers:
    My-Header: header value

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.

mapserver

Options for the Mapserver source.

binary

The complete path to the mapserv executable. Required if you use the mapserver source.

working_dir

Path where the Mapserver should be executed from. It should be the directory where any relative paths in your mapfile are based on. Defaults to the directory of binary.

Image Format Options

New in version 1.1.0.

There are a few options that affect how MapProxy encodes and transforms images. You can set these options in the globals section or individually for each source or cache.

Options

Available options are:

format
The mime-type of this image format. The format defaults to the name of the image configuration.
mode
One of RGB for 24bit images, RGBA 32bit images with alpha, P for paletted images or I for integer images.
colors
The number of colors to reduce the image before encoding. Use 0 to disable color reduction (quantizing) for this format and 256 for paletted images. See also globals.image.paletted.
transparent
true if the image should have an alpha channel.
resampling_method
The resampling method used for scaling or reprojection. One of nearest, bilinear or bicubic.
encoding_options
Options that modify the way MapProxy encodes (saves) images. These options are format dependent. See below.
opacity
Configures the opacity of a layer or cache. This value is used when the source or cache is placed on other layers and it can be used to overlay non-transparent images. It does not alter the image itself, and only effects when multiple layers are merged to one image. The value should be between 0.0 (full transparent) and 1.0 (opaque, i.e. the layers below will not be rendered).

encoding_options

The following encoding options are available:

jpeg_quality
An integer value from 0 to 100 that defines the image quality of JPEG images. 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.
quantizer

The algorithm used to quantize (reduce) the image colors. Quantizing is used for GIF and paletted PNG images. Available quantizers are mediancut and fastoctree. fastoctree is much faster and also supports 8bit PNG with full alpha support, but the image quality can be better with mediancut in some cases. The quantizing is done by the Python Image Library (PIL). fastoctree is a new quantizer that is not yet available in any official PIL release. You need install a development package of PIL:

pip install https://bitbucket.org/olt/pil-2009-raclette/get/tip.tar.gz

Global

You can configure image formats globally with the image.formats option. Each format has a name and one or more options from the list above. You can choose any name, but you need to specify a format if the name is not a valid mime-type (e.g. myformat instead of image/png).

Here is an example that defines a custom format:

globals:
  image:
    formats:
      my_format:
        format: image/png
        mode: P
        transparent: true

You can also modify existing image formats:

globals:
  image:
    formats:
      image/png:
        encoding_options:
          quantizer: fastoctree

MapProxy will use your image formats when you are using the format name as the format of any source or cache.

For example:

caches:
  mycache:
    format: my_format
    sources: [source1, source2]
    grids: [my_grid]

Local

You can change all options individually for each cache or source. You can do this by choosing a base format and changing some options:

caches:
  mycache:
    format: image/jpeg
    image:
      encoding_options:
        jpeg_quality: 80
    sources: [source1, source2]
    grids: [my_grid]

You can also configure the format from scratch:

caches:
  mycache:
    image:
      format: image/jpeg
      resampling_method: nearest
    sources: [source1, source2]
    grids: [my_grid]

Notes

Scale vs. resolution

Scale is the ratio of a distance on a map and the corresponding distance on the ground. This implies that the map distance and the ground distance are measured in the same unit. For MapProxy a map is just a collection of pixels and the pixels do not have any size/dimension. They do correspond to a ground size but the size on the map is depended of the physical output format. MapProxy can thus only work with resolutions (pixel per ground unit) and not scales.

This applies to all servers and the OGC WMS standard as well. Some neglect this fact and assume a fixed pixel dimension (like 72dpi), the OCG WMS 1.3.0 standard uses a pixel size of 0.28 mm/px (around 91dpi). But you need to understand that a scale will differ if you print a map (200, 300 or more dpi) or if you show it on a computer display (typical 90-120 dpi, but there are mobile devices with more than 300 dpi).

You can convert between scales and resolutions with the mapproxy-util scales tool.

MapProxy will use the OCG value (0.28mm/px) if it’s necessary to use a scale value (e.g. MinScaleDenominator in WMS 1.3.0 capabilities), but you should always use resolutions within MapProxy.

WMS ScaleHint

The WMS ScaleHint is a bit misleading. The parameter is not a scale but the diagonal pixel resolution. It also defines the min as the minimum value not the minimum resolution (e.g. 10m/px is a lower resolution than 5m/px, but 5m/px is the minimum value). MapProxy always uses the term resolutions as the side length in ground units per pixel and minimum resolution is always the higher number (100m/px < 10m/px). Keep that in mind when you use these values.