Print Support and server side issues printing WMTS and TMS layers

[offtherailz]

Description

We need to provide support for Printing for:

• WMTS:

  • KVP (gs-stable geoserver WMTS): http://gs-stable.geo-solutions.it/geoserver/wmts
  • REST ( add this WMTS catalog https://www.basemap.at/wmts/1.0.0/WMTSCapabilities.xml)

• TMS :

  • TMS 1.0.0:
    • https://public.sig.rennesmetropole.fr/geowebcache/service/tms/1.0.0
    • http://gs-stable.geo-solutions.it/geoserver/gwc/service/tms/1.0.0
  • tileProvider (xyz) :
    • Preconfigured (Backgrounds, e.g. NASA GIBS, OpenTopoMap, Stamen ...)
      • Open Street Maps (already printable)
      • OpenTopoMap
      • Stamen Toner Lite
      • NASAGIBS Night 2012
      • Basemap.at Grau (basemap TMS have to be enabled adding in localConfig.json allowedProviders: "ALL" )
      • Basemap.at HIDPI
      • Basemap.at Orthofoto
  • from Custom URL: add TMS --> custom with URL: https://nls-{s}.tileserver.com/nls/{z}/{x}/{y}.jpg and advancedOptions:

subdomains: [
            '0',
            '1',
            '2',
            '3'
        ]

Server side issues

next comments concerns some issues on back-end that has been fixed acting on the request and on the print config.yml.
If you find the issue on WMTS, we need to update config.yml on the related project.

See this issue "Other useful information":
#5189 (comment)

And expecially the linked comment: https://github.com/geosolutions-it/austrocontrol-C125/issues/144#issuecomment-620455864

We need to investigate if these 2 issues are cause by:

• Wrong print spec (or not documented properties we could use)
• Issues with mapfish print
• Issues with GeoServer

Therefore plan a solution to mitigate this problem

Copy of the original comments issues :

For the WMTS layer to mapfish print specification, setting opacity to 1, hides the other layer background, in this case, WMS. I have attached the POST call with the spec sent for WMTS.

Is it due to some problems with the spec request?

Ex: http://localhost:8081/?debug=true#/viewer/openlayers/23534

POST Request (Spec)
POST_WMTS.txt

Screenshot:
Opacity - 0.45

Opacity - 1

TMS:
For TMS, I have encountered the below issue.
Mapfish print specification for TMS

POST-SPEC
POST_TMS.txt

Ex: http://localhost:8081/?debug=true#/viewer/openlayers/24413

After conversion, the mapfish prints the tile with white background in place of the TMS layer,
I have tried with three sample TMS services, but the results are same.
https://public.sig.rennesmetropole.fr/geowebcache/service/tms/1.0.0
https://osm.geobretagne.fr/gwc01/service/tms/1.0.0
http://gs-stable.geo-solutions.it/geoserver/gwc/service/tms/1.0.0

Screenshot

Note: Since the service appends the serviceVersion to the path, so I tried removing the service version in baseURL while sending spec but the result is still the same.

[mbarto]

@offtherailz @tdipisa in general:

• we can change brokenUrlPlaceholder in config.yaml to use an inline transparent PNG (this avoids white tiles when we have errors, and replaces them with transparent tiles):

brokenUrlPlaceholder: 'data:png,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNkYAAAAAYAAjCB0C8AAAAASUVORK5CYII='

About TMS: the attached request is wrong. This is one that works:

POST_TMS.txt

The main differences are:

• the baseUrl should not include 1.0.0
• the layer should be fully qualified (with EPSG and format)
• I also changed resolutions and origin to a standard value for EPSG:3857

[mbarto]

About WMTS, the attached request works fine with the transparent brokenUrlPlaceholder I mentioned in my previous comment

[mbarto]

@offtherailz @tdipisa let me know if this is enough to solve your issues, or need anything more / else

[tdipisa]

@mbarto thank you so much for the investigation, it is really useful. I think it is enough for the moment, @offtherailz should be able to replicate according to your feedback and check the TMS code for a fix.

[offtherailz]

@ElenaGallo and @mbarto :
#5910 add a fix for the WMTS part. Still need to investigate for the second part

[offtherailz]

Blocked because to be tested it needs to merge #5189

[ElenaGallo]

@offtherailz

The layer (WMTS/TMS) no longer prints after changing the layer opacity for the first time.

How to repriduce

• Open a new map
• Add a WMTS layer
• On TOC change the opacity of the layer
• Click on Burger Menu
• Click on Print and print the map

Current Result
The layer is no longer printed. (if the opacity is brought back to 100% the layer is not printed anyway)

[tdipisa]

@offtherailz please remember to update the revision in c125 project for this