Write an ArcPy script to find maps throughout a folder tree and re-path layer data sources

Summary

When data servers are upgraded or replaced, maps with layers that reference data on those systems may need to be updated to refer to data on a different system. The following is an example of a script to replace data sources of raster layers in maps residing in many different subfolders.

As an example, suppose the data sources for all color images were located in:

<drive>:<folder tree>/images/color

<drive>:<folder tree>/images

Note:
If this example does not match the file organization in the prevailing environment, the functions illustrated may be helpful in developing a custom workflow.

Procedure

Code:
import arcpy, os

MapMainFolder = arcpy.GetParameterAsText(0) # topmost folder of maps to be updated
NewDataPath   = arcpy.GetParameterAsText(1) # folder to which the raster data sources have been moved

for (root, dirs, files) in os.walk (MapMainFolder):
  for fileName in files:
    if os.path.splitext (fileName)[1] == ".mxd":
      arcpy.AddMessage (fileName)
      fullPath = os.path.join (root, fileName)
      mxd = arcpy.mapping.MapDocument (fullPath)
      rasterLayersUpdated = 0
      for layer in arcpy.mapping.ListLayers (mxd): # list all layers in all dataframes
        if layer.isRasterLayer:
          if layer.supports ("SERVICEPROPERTIES"):
            if layers.serviceProperties ['ServiceType'] == "ImageServer":
              pass # don't try to re-path an online basemap
          dataSrc = layer.dataSource
          Color = 0
          dataRoot = os.path.dirname (dataSrc)
          if dataRoot.find ("Color") > 0:
            newPath = os.path.join (NewDataPath, "Color")
          else: # B&W
            newPath = NewDataPath
          layer.replaceDataSource (newPath, "RASTER_WORKSPACE", os.path.basename (dataSrc))
          rasterLayersUpdated += 1
      if rasterLayersUpdated > 0:
        mxd.save()