Final result PDF map generated by Arcgis Server
https://gisportal.hrsa.gov/server/rest/directories/arcgisoutput/Print/HDWPrint_GPServer/_ags_e6aea9510a224e49937d2746bb4fc12a.pdf
ESRI document:
ExportWebMap specification https://developers.arcgis.com/rest/services-reference/enterprise/exportwebmap-specification.htm
Export Web Map (Server) https://pro.arcgis.com/en/pro-app/latest/tool-reference/server/export-web-map.htm
How to find arcgis server that can print PDF map?
Google search 'GPserver Export Web Map'
The following arcgis server have the geoprocess server with printing function, you can use any of them to print a PDF map with same result, no difference. Any of following arcgis server endpoint act as an "online PDF map printer". You create your own JSON string, excute on any of these "online printer" will give you the same result with no difference.
ESRI's online printer is here
https://sampleserver6.arcgisonline.com/arcgis/rest/services/Utilities/PrintingTools/GPServer/Export%20Web%20Map%20Task
Click 'Execute Task' at the bottom of the page
https://sampleserver6.arcgisonline.com/arcgis/rest/services/Utilities/PrintingTools/GPServer/Export%20Web%20Map%20Task/execute
USGS's online printer is here
https://cbrsgis.wim.usgs.gov/arcgis/rest/services/Utilities/PrintingTools/GPServer/Export%20Web%20Map%20Task
https://cbrsgis.wim.usgs.gov/arcgis/rest/services/Utilities/PrintingTools/GPServer/Export%20Web%20Map%20Task/execute
Many cities arcgis server also have online printer for you
https://arcgis-svr.ci.eureka.ca.gov/arcgis/rest/services/ExportWebMapYes/GPServer/Export%20Web%20Map
http://gismaps.hamiltontn.gov:6080/arcgis/rest/services/ZIMS/ZIMSExportWebMap/GPServer/Export%20Web%20Map
Today I am going to use HRSA's printer as example, but you can use any printer without difference.
https://gisportal.hrsa.gov/server/rest/services/Print/HDWPrint/GPServer/Export%20Web%20Map
https://gisportal.hrsa.gov/server/rest/services/Print/HDWPrint/GPServer/Export%20Web%20Map/execute
How to use these online printer to print PDF maps?
1) find the JSON string for the layers you want to show on the map ( How to ? See my other article about it)
https://transparentgov.net/json2tree/esri/server/folder.html?org=https%3A%2F%2Fgisportal.hrsa.gov%2Fserver%2Frest%2Fservices&url=https%3A%2F%2Fgisportal.hrsa.gov%2Fserver%2Frest%2Fservices&select_folder=85&select_layer=0
2) use any text editor to edit JSON string that includes all the layers you need
3) Copy paste JSON text string in "printer" Web Map as Json window
4) Wait and open the final result PDF link