At San Mateo County (Calif.) GIS, we adapted Esri’s Public Map Gallery template into a County Geodata Catalog. The purpose of the Catalog was to get county geodatabase layers out to the public as quickly as possible. (SMC GIS published a separate Public Map Gallery to share published maps authored for specific audiences.)
The Geodata Catalog put a lot of data into the hands of more experienced geodata users out in the public domain. To quickly publish the Catalog, we took advantage of the county’s ArcGIS Server and some less well-known features at ArcGIS Online.
Here’s how county geodatabase layers went public in a matter of hours:
1. Serve up some Metadata Lite – We authored map services each that contained one to a dozen geodatabase layers. We used a standard template for “metadata lite” — descriptive information that appears in the map service REST catalog. (See my post about deciding how many map layers to combine into one service.)
2. Create an ArcGIS Online Group – Once the service were published on the county’s ArcGIS Server, we created a San Mateo County Public Geodata Catalog group at ArcGIS Online.
3. “Register” Map Services – With the group in place, we rapidly added maps to the group by using the “Add Item” button
When you paste in the URL for your ArcGIS map servicie hit “tab”, the Title and Tags fields are auto-filled with the fielded content from your “metadata lite” in the REST catalog page for this service:
Shining a light on County geodata
At San Mateo County (Calif.) GIS last summer, we wanted to get as many of the county’s geodatabase layers as possible into the hands of the public and of developers of location-based services. To do this quickly and at very low cost, we combined the Esri Map Gallery template with some less-known functions at ArcGIS Online to create a San Mateo County Geodata Catalog.
Most of the county’s geodata had never been seen by the public. Although many of the data sets were available through FTP or by email request , you had to be a GIS expert to find and understand the data description in the County’s online metadata catalog, then obtain, import, and view the data in desktop GIS software. The Geodata Gallery put each data layer into a simple web map for the firs time, so that the data was easy to visualize geographically, to evaluate for a given purpose, and to combine with other data.
Same Map Gallery but different
The San Mateo County Geodata Catalog looks like the Esri map gallery. But there are key differences in its implementation and use. First, we made sure that our geodatabase layers were documented in each ArcGIS map document properties fields that appear in the published ArcGIS Server REST catalog. (See my post about publishing “Metadata Lite”.) Once the map services were published, we “registered” each map service at ArcGIS Online. This allowed us to rapidly produce dozens of web maps for all of the county’s map services literally in minutes.
“Registering” map services – What you do you don’t
Although the default published web maps are not
it’s really designed for the County’s more GIS-savvy partners and stakeholders, rather than for the general public.
Authoring the Map Service
The Geodata Catalog points the user to all map services published by the County. Each map service contains one or more layers from the County geodatabase. GIS server resources were limited, so we reduced the number of map services by combining geodatabase layers that are topically similar, or that contain polygons that don’t overlap each other within a single map service.
Why be careful about overlapping polygons? Because San Mateo County GIS has centered its web map publishing at ArcGIS Online. AGO’s web map authoring tools allow layer manipulation (e.g. transparency, position above/below other layers) only for the entire map service, but not for individual layers in the map service. So all polygons in a map service end up with the same transparency and other settings. We keep large polygons in separate map services to avoid interference.
Keywords and Tags
To publish each map service for the Geodata Catalog, we started with an ArcMap document (.mxd) template that has properties fields pre-filled with SMC GIS standard text. We paid close attention to location and topic keywords in the map document fields, because these keywords get imported as-is when you “register” the map service with ArcGIS Online. Good tags give better results when you search for layers to add to ArcGIS Online maps.
Registering map services at ArcGIS Online
“Registering the map service” is a specific process that Esri has set up to ensure that ArcGIS Server map services are easy to find and add to maps at ArcGIS Online. Here are the steps register each service so that it also populates the SMC Geodata Catalog (map picker):
When logged in to AGO at My Content, navigate to the Geodata Catalog folder (Public or Intranet).
Click Add Item > ArcGIS Server web service > [REST URL] ; paste in the REST URL for the SMC map service.
Tab through the other fields, and AGO autofills the tags and description that already appear in the published map service.
For this project, we have changed the auth-filled title to a standard title = “[map service name without hyphens ] – San Mateo County”. (We appended “(Intranet)” while we were still publishing these to the dev server.)
Once the map service app is saved at AGO, click the “Share”button to share with “Everyone” plus only one AGO group (Public or Intranet Geodata Catalog)
You can edit the thumbnail by snapping a screenshot of the zoomed in map service displayed in the map. Optimum file size is 200×133 pixels.
Update the SMC Map Service Publishing Log, if it is to be used to manage map service workflows and/or the Excel file will be used to generate the optional SMC Map Services Dashboard.