I previously posted about how to quickly repath links based on some control mechanisms. Enter BIM 360, and the wild world of Revit cloud worksharing… I expect that it will be commonplace now for existing projects and datasets to move across to BIM360 ‘mid project’. But that creates some interesting problems, like creating folders, dealing with the initiation process, and replacing local Revit Links with their cloud versions.

This post is focused on that process of changing all of the Revit link paths to link to the BIM 360 models. Unfortunately, the previous method I used (TransmissionData, like eTransmit) is not available for cloud hosted models. So how do we automate this process?

We went about it this way:

  1. Initiate all Revit models on the BIM 360 Document Management cloud (manually, for now)
  2. Create one federated model on the BIM 360 cloud that links in all the other cloud hosted Revit models. You might do this one manually, using Reload From in the Manage Links dialog box.
  3. Once you have that one ‘super host model’, use a batch process to harvest all of the cloud model data
  4. Using the harvested data, create a script that implements a Reload From method to batch reload local models from their cloud counterpart

On the journey to solving step 3, I experimented with a few different methods. I discovered that you need to use the ExternalResource class to get information about BIM 360 cloud models (not ExternalReference).

I also realised that I had to deal with Reference Information, which appears to be a .NET dictionary per link that stores some funky Forge IDs and so on. But I want to store all this data in our VirtualBuiltApp BIM Management system, so I had to serialise the Reference Information to a string that could be stored in a database VARCHAR field (or push to Excel if you are still doing things the old way). Dimitar Venkov gave me a few tips about using JSON with IronPython in Dynamo (thanks mate!), so after that all the harvesting pieces were in place!

Here is some of the harvesting and JSON code. Notice that I played around with using a container class to pass data between Dynamo nodes. In the end, JSON string was the answer:

 data = []
for u in unwraps:

class dummy(object):
    def ToString(self):
        return 'container'
container = dummy()

sdicts = []

for y in data:
    dictinfo = ExternalResourceReference.GetReferenceInformation(y)
    container.dictinfo = dictinfo

The next step was to create the ‘batch reload from’ tool. Now that we had the necessary data, we just had to use it to grab the matching cloud path information (from our database) and apply it to each Revit link.

I created a node that essentially built a new reference path from the JSON and other data that we had harvested. Here is some of that code:

 des = []
for x in referencesInfo:
newdicts = []
for y in des:
    newdicts.append(Dictionary[str, str](y))

serverGuids = []
for g in serverIdsIn:
    tempguid = Guid(g)

newrefs = []
for z in range(len(referencesInfo)):
    serverIdIn = serverGuids[z]
    referenceInfo = newdicts[z]
    versionInfo = versionsInfo[z]
    sessionPathIn = sessionsPathIn[z]
    tempRef = ExternalResourceReference(serverIdIn, referenceInfo, versionInfo, sessionPathIn)

OUT = newrefs

The final step was to get a RevitLinkType and a matching ReferenceInformation and apply them to each other. I stored the data in our cloud based BIM Management Application, VirtualBuiltApp. Then I could easily just pull the data into Dynamo with a suitable database connector, and match up the RevitLinkType in the current file with its associated cloud identity. For that genuine 90s feel, you could use Excel to store the data as it is just a JSON string and some other strings:

Here is the key bit of code that actually changes the link path (without all of my other error checking bits and pieces):

        newCloudPath = newCloudPaths[l]
        reloaded = fileToChange.LoadFrom(newCloudPath, defaultconfig)
        successlist.append("Failure, not top level link or workset closed")

To actually implement the script and get productive, I opened 4 instances of Revit, and then used this process in each instance:

  1. Open the Revit file from BIM 360, with Specify… all worksets closed
  2. Unload all links
  3. Open all worksets
  4. Run the Reloader Script
  5. Confirm link status in Manage Links
  6. Optional: Add ‘bim 360 links loaded’ text to Start View (just for tracking purposes)
  7. Optional: Add comment to VirtualBuiltApp (optional, for tracking purposes)
  8. Close and Sync

In this way I can have 4 or more sessions operating concurrently, fixing all the link paths automatically, and I just need to gently monitor the process.

One nice thing is that I set the script up to immediately Unload a link after it had obtained and applied the new Path information. This means that the Revit instance does not get bogged down with many gigs of link data in memory, and in fact this is way faster than trying to use Manage Links for a similar process.

Ideally I would like to fully automate this, to the point where it opens each file, runs the script, and syncs. Unfortunately, time didn’t allow me to get all the code together for that (for now).

Finally, because we are using our custom built schema and validation tools, we can easily create visuals like this:

Modified versions of the Dynamo graphs can be found on the Bakery Github here:

dyn folder

The Revit API is actually something pretty special. People will go on and on about how Revit needs this feature or that feature, but the fact is that you can build almost any feature you like with the API. Recently, I have been running quite a few batch operations from the scope of a federated Revit model: so I will have one RVT file, with hundreds of Revit links, and I will process them from that main federated model.

On one recent project, we had to deliver to a Client a linked dataset, with Revit link file paths resolving correctly. As you know, people work in many different IT environments, and the pathing of Revit links may vary widely.

I set up an ‘approved’ list of Revit file paths, that looked something like this:

I knew that in Dynamo with Python I could get a lot of information about linked files using the ExternalFileReference class. What I discovered during this process is that there is a TransmissionData API class that let’s you do some pretty interesting things…

You see, I was thinking I would have to set up a batch method to open this files, change the file paths, and close them. But the TransmissionData class is basically what is implemented in eTransmit for Revit – it allows you to ‘lightly touch’ the Revit file and simply change the Revit link paths, and also set a switch saying ‘this file has been transmitted’. This puts the file in an appropriate state for re-opening in the new path environment. Pretty cool huh?

Once I figured out how to implement those TransmissionData actions in Python, I just had to build a node that, running from the federated model:

  • examines each link for the links inside of it
  • replaces erroneous paths with the correct file path
  • sets the new paths to the file

I did this in the hacky way of a “counter with List.Map” in Dynamo. In the future I’ll probably fix it up to be a ‘proper’ Python script but this works for now. In about an hour it fixed the linked file paths of 600 Revit links, all with the click of a single button 🙂

You can download the main definition here:

External References FINAL

You can get the supporting nodes from GitHub here:


As usual, please use with care. And it is probably worth backing up your files before running something like this.

It is kinda more Python than Dynamo but hey, you get the picture 🙂

In fact, here is the Python code:

import clr
from Autodesk.DesignScript.Geometry import *

# Import RevitAPI
import Autodesk
from Autodesk.Revit.DB import *

import RevitServices
from RevitServices.Persistence import DocumentManager
from RevitServices.Transactions import TransactionManager

from System.Collections.Generic import *

import Revit

from System import Guid

import System

import sys
pyt_path = r'C:\Program Files (x86)\IronPython 2.7\Lib'

import os.path

doc = DocumentManager.Instance.CurrentDBDocument
uiapp = DocumentManager.Instance.CurrentUIApplication
app = uiapp.Application

tempvalue = IN[0]
approvedFilenames = IN[1]
approvedFilepaths = IN[2]
targetfilepath = IN[5]

def stripquotes(string):
	string = string[1:-1]
	return string

transData = TransmissionData.ReadTransmissionData(tempvalue)
erefids = transData.GetAllExternalFileReferenceIds()
refdata = []
for x in erefids:

currentpaths, currenterefType, currenterefPath, pstr = [], [], [], []

for e in refdata:
for s in currentpaths:
filenames = []
for p in pstr:
	templist = os.path.split(p)
newpath = []
indices = []
failpath = []
origcounter = 0
matchrefs = []
newpathtypes, newbools = [], []
pathtypevar = IN[3]
for f in filenames:
	tempindex = approvedFilenames.index(f) if f in approvedFilenames else -1
	if tempindex == -1:
	origcounter = origcounter + 1

elementcount = len(erefids)
hostfile = currentfilepathstring * elementcount
currentdata = []

newdata = []

setlength = len(newpath)
setcounter = range(setlength)
successreport = []
setdata = IN[4]
if setdata:
	for s in setcounter:
			transData.SetDesiredReferenceData(matchrefs[s], newpath[s], newpathtypes[s], newbools[s])
			successreport.append("Success setting data")
			successreport.append("Failure setting data")
	successreport.append("You need to set the switch to True")

if setdata:
		transData.IsTransmitted = True
		transData.WriteTransmissionData(targetfilepath, transData)
		successreport.append("Success WRITING data")
		successreport.append("Failure WRITING data")
#Assign your output to the OUT variable.
OUT = successreport, currentdata, newdata

If you want to read more about the API methods used:




Have you ever wondered how to convert a Revit macro into an addin? You can follow Harry’s steps over at this post.

What about getting some sample code for Python and Ruby Revit projects? From AEC DevBlog:

… the code examples are hidden in the default macro projects created by macro manager, see below image, the project is the default python project, there are several “if False” statements, if you remove the line of “if False”, uncomment and unindent 4 spaces to methods below it, the methods will become available macros and appear in the macro manager, and you will see the same “if false” in Ruby projects too:

How to find python macro exmaples

Original post: http://adndevblog.typepad.com/aec/2016/03/revitapi-how-to-find-code-examples-for-macro-of-python-or-ruby.html

You may also be interested in the Revit Python Wrapper here http://revitpythonwrapper.readthedocs.io/en/latest/