Dear developer and smart home enthusiasts,
today, we want to contact you to talk with you about the recent activities that are taking place concerning the interface of the heating systems, also known as the Viessmann API. As most of you might have already received our Email in which we informed you about the upcoming changes concerning the use of the API, we would like to open this thread to continue the discussion openly and transparent with you and pick up on the discussions in this thread. Here is again a brief summary of the main points from our message:
> As Viessmann, it’s in our responsibility to provide our users with reliant and safe products, including features and services around those products
> We are impressed to see your interest in connecting and interacting with your heating system and that you found a solution for your specific use case without a description or support from our side
> However, it challenges us to check and channel the method and frequency of requests to our IoT Services in order to keep those stable and available for all our users
> What is even more important is that for these solutions, we as Viessmann currently cannot guarantee a safe and reliant operation of your heating system
This has the following steps that we have to take:
> In order to keep operation through our API safe and still give you the chance to interact with your system, we limit the use for all applications by setting a threshold for the requests. The limit is set for both a larger (e.g. daily) and a smaller (<15 mins) time scale. Reaching the limit will prevent you to execute any further requests with your account in the specific time frame. So please make sure to adapt the frequency of the requests of your current solution to avoid reaching the limitation.
> We are heavily working on providing a solution for all users that is 1) approved & safe to use, 2) properly explained and 3) gives you the functions and information you need for your specific use case. At the same time, this will also be moment when the solution is in place where we cannot allow any other ways of accessing our API. To make things clear: Your already built and currently used functions will still be able to use, it’s only that you will need a new API client provided through the Portal that can be self-managed by the user himself.
We also received a lot of questions via Mail and also in this forum, which we are going to answer for everyone individually. We also saw that the most common question among the responses was the demand for a local API. This is a reasonable request and we appreciate and take the demand very seriously. However, we will not able to provide you a solution for this in the near future. This feature (as all other features and requests by users) are permanently discussed and evaluated and brought together with all other strategic decisions that Viessmann is taking.
I again would like to encourage everyone to participate in the development and make sure to sign in here to get an early access to the Developer Portal. Also, we are hoping to have a constructive discussion here in this thread. We are really looking forward to work jointly together with you on ideas and co-create future solutions!
P.S.
As stated in the previous thread and in certain Emails we received, we are aware that some users might expect a communication in german from us, as Viessmann is of course a company with German heritage. However, since we are providing climate solutions all over the world and especially programming / APIs is natively described in english, there is no other option than communicating in english first. This has already been greatly explained by @thetrueavatar in the previous thread.
All the best!
Michael Hanna
Viessmann Developer Portal
EDIT:
In order to support you more on adjusting your current solutions according to the current limitation, here is how the threshold works:
We have a rate limit with sliding window. Whenever the first request arrives, we open a time window and count all request in that window. If the number of requests reach the limitation, we block all incoming user requests until the time window ends. Then, with the next user request, a new time window opens.
Currently, we have the following limits active:
120 calls for a time window of 10 minutes
1450 calls for a time window of 24 hours
Please take note that we are taking the right to adjust the limits if seen necessary. Information about adjustment of the threshold will be given with a reasonable amount of time in advance for all affected user.
EDIT2:
For all who experienced a ban after the limitation time frame with a few number of API requests: Our team fixed an issue with the limitation, which is taking effect since today and should solve this problem. We are still analyzing the behavior, but for now it looks ok.
