Initial implementation

Former-commit-id: 68293cbaa3

app/base.py

@@ -13,22 +13,59 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http:#www.gnu.org/licenses/>.
 
+import os
+from abc import ABC, abstractmethod
+
 def get_stack(config, stack):
-    return base_stack(config, stack)
+    if stack == "package-registry":
+        return package_registry_stack(config, stack)
+    else:
+        return base_stack(config, stack)
 
 
-class base_stack():
+class base_stack(ABC):
 
     def __init__(self, config, stack):
         self.config = config
         self.stack = stack
 
+    @abstractmethod
     def ensure_available(self):
-        if self.config.verbose:
-            print(f"Checking that base stack {self.stack} is available")
-        return 1
+        pass
+
+    @abstractmethod
+    def get_url(self):
+        pass
+
+
+class package_registry_stack(base_stack):
+
+    def ensure_available(self):
+        self.url = "<no registry url set>"
+        # Check if we were given an external registry URL
+        url_from_environment = os.environ.get("CERC_NPM_REGISTRY_URL")
+        if url_from_environment:
+            if self.config.verbose:
+                print(f"Using package registry url from CERC_NPM_REGISTRY_URL: {url_from_environment}")
+            self.url = url_from_environment
+        else:
+            # Otherwise we expect to use the local package-registry stack
+            # First check if the stack is up
+            # If not, print a message about how to start it and return fail to the caller
+            return False
+            # If it is available, get its mapped port and construct its URL
+            self.url = "http://gitea.local:3000/api/packages/cerc-io/npm/"
+        return True
 
     def get_url(self):
-        return "http://gitea.local:3000/api/packages/cerc-io/npm/"
+        return self.url
 
-# TODO: finish this implementation for the npm package registry
+# Temporary helper functions while we figure out a good interface to the stack deploy code
+
+
+def _is_stack_running(stack):
+    return True
+
+
+def _get_stack_mapped_port(stack, service, exposed_port):
+    return 3000