Alternate Title: “How the Power BI Map and Filled Map secretly sabotage ArcGIS Maps for Power BI!” (cue nefarious music)
The inspiration for this post came from a tweet by Power BI expert Chris Webb after he encountered an issue with the ESRI ArcGIS Map. As noted in his tweet, documentation is available on the ArcGIS website that walks through how to solve the storage issue that some users may encounter in Power BI Desktop and in various browsers.
When ArcGIS Maps was in Preview, it showed a blank visual when this problem occurred. Now that it is generally available, it displays a warning message with error code 5989-0001. The blank visual in particular caused a lot of confusion for various users who encountered the problem. Some users even considered ArcGIS Maps an untrustworthy or unreliable visual as a result.
In reality, ArcGIS Maps is not the primary culprit. It may seem that ArcGIS Maps is at fault because it is the visual that provides the evidence for a deeper problem. Apart from perhaps arguing that the visual should be coded to try to automatically clear up storage space rather than rely on end users to do so, it is not to blame.
Browsers limit sites to 10MB for localStorage. Using any browser’s “Inspect” tool, you can view what appears in localStorage. The ArcGIS documentation covers how to access and manually clear the storage. Rather than immediately clear it though, look at what appears there.
For Power BI Desktop, there is also a “Local Storage” folder, but the folder contents are less transparent than what you can view in a browser with Power BI Service. The limit is higher than 10MB for Desktop, but there is still a limit.
If you have recently cleared your storage or are starting with Power BI for the first time, there will only be a few items that appear. In fact, the ArcGIS Map maintains a small footprint no matter what you plot on it or whatever type of location data is used. The same five “_esri_” keys appear, which by itself is not enough to reach the limit.
There is something besides ArcGIS Maps at work.
Something that starts small but ends up hogging all of the storage space.
Something that prevents ArcGIS Maps from getting the miniscule amount of localStorage space it needs.
The culprit is Bing Maps eventually using up the available storage. How does it accomplish this astounding feat?
Little by little, it adds up when you use the Map and Filled Map. Fractional kilobyte by fractional kilobyte, Power BI stores every location you geocode with Bing Maps in localStorage. Power BI uses Bing Maps to retrieve coordinates for addresses, postal codes, and other location types that are not already latitude and longitude coordinates. These coordinates are then cached in localStorage for potential use later.
If you use the Map and Filled Map enough and never clear the browser storage (or the CEF folder for Power BI Desktop), eventually you will encounter problems with ArcGIS Maps. ArcGIS Maps draws the ire because it is the visual that shows the problem. The other map types and not ArcGIS Maps, however, are the gluttons.