Add a command for generating dataverse data file

setup.py

@@ -1,3 +1,4 @@
+from distutils.cmd import Command
 from setuptools import setup, find_packages
 import sys
 import versioneer
@@ -8,6 +9,35 @@ else:
     with open("README.md", encoding="utf8") as f:
         readme = f.read()
 
+
+class GenerateDataverseInstallationsFileCommand(Command):
+    description = "Generate Dataverse installations data map"
+    user_options = []
+
+    def initialize_options(self):
+        self.url = (
+            "https://services.dataverse.harvard.edu/miniverse/map/installations-json"
+        )
+
+    def finalize_options(self):
+        pass
+
+    def run(self):
+        from urllib.request import urlopen
+        import json
+
+        resp = urlopen(self.url, timeout=5)
+        resp_body = resp.read()
+        data = json.loads(resp_body.decode("utf-8"))
+        if "installations" not in data:
+            raise ValueError("Malformed installation map.")
+        with open("repo2docker/contentproviders/dataverse.json", "wb") as fp:
+            fp.write(resp_body)
+
+
+__cmdclass = versioneer.get_cmdclass()
+__cmdclass["generate_dataverse_file"] = GenerateDataverseInstallationsFileCommand
+
 setup(
     name="jupyter-repo2docker",
     version=versioneer.get_version(),
@@ -48,7 +78,7 @@ setup(
     ],
     packages=find_packages(),
     include_package_data=True,
-    cmdclass=versioneer.get_cmdclass(),
+    cmdclass=__cmdclass,
     entry_points={
         "console_scripts": [
             "jupyter-repo2docker = repo2docker.__main__:main",