Add more informative error messages to context commands

data_safe_haven/commands/context.py

@@ -22,7 +22,7 @@ def show() -> None:
     try:
         settings = ContextSettings.from_file()
     except DataSafeHavenConfigError as exc:
-        print("No context configuration file.")
+        print("No context configuration file. Run `dsh context add` to create one.")
         raise typer.Exit(code=1) from exc
 
     current_context_key = settings.selected
@@ -39,7 +39,11 @@ def show() -> None:
 @context_command_group.command()
 def available() -> None:
     """Show the available contexts."""
-    settings = ContextSettings.from_file()
+    try:
+        settings = ContextSettings.from_file()
+    except DataSafeHavenConfigError as exc:
+        print("No context configuration file. Run `dsh context add` to create one.")
+        raise typer.Exit(code=1) from exc
 
     current_context_key = settings.selected
     available = settings.available
@@ -56,7 +60,11 @@ def switch(
     key: Annotated[str, typer.Argument(help="Key of the context to switch to.")]
 ) -> None:
     """Switch the selected context."""
-    settings = ContextSettings.from_file()
+    try:
+        settings = ContextSettings.from_file()
+    except DataSafeHavenConfigError as exc:
+        print("No context configuration file. Run `dsh context add` to create one.")
+        raise typer.Exit(code=1) from exc
     settings.selected = key
     settings.write()
 
@@ -145,7 +153,12 @@ def update(
     ] = None,
 ) -> None:
     """Update the selected context settings."""
-    settings = ContextSettings.from_file()
+    try:
+        settings = ContextSettings.from_file()
+    except DataSafeHavenConfigError as exc:
+        print("No context configuration file. Run `dsh context add` to create one.")
+        raise typer.Exit(code=1) from exc
+
     settings.update(
         admin_group_id=admin_group,
         location=location,
@@ -160,22 +173,39 @@ def remove(
     key: Annotated[str, typer.Argument(help="Name of the context to remove.")],
 ) -> None:
     """Removes a context."""
-    settings = ContextSettings.from_file()
+    try:
+        settings = ContextSettings.from_file()
+    except DataSafeHavenConfigError as exc:
+        print("No context configuration file, so no contexts to remove.")
+        raise typer.Exit(code=1) from exc
     settings.remove(key)
     settings.write()
 
 
 @context_command_group.command()
 def create() -> None:
     """Create Data Safe Haven context infrastructure."""
-    context = ContextSettings.from_file().assert_context()
+    try:
+        context = ContextSettings.from_file().assert_context()
+    except DataSafeHavenConfigError as exc:
+        print(
+            "No context configuration file. Run `dsh context add` before creating infrastructure."
+        )
+        raise typer.Exit(code=1) from exc
+
     context_infra = ContextInfrastructure(context)
     context_infra.create()
 
 
 @context_command_group.command()
 def teardown() -> None:
     """Tear down Data Safe Haven context infrastructure."""
-    context = ContextSettings.from_file().assert_context()
+    try:
+        context = ContextSettings.from_file().assert_context()
+    except DataSafeHavenConfigError as exc:
+        print(
+            "No context configuration file. A context configuration must exist before the context can be torn down."
+        )
+        raise typer.Exit(code=1) from exc
     context_infra = ContextInfrastructure(context)
     context_infra.teardown()

data_safe_haven/context_infrastructure/infrastructure.py

@@ -10,6 +10,12 @@ def __init__(self, context: Context) -> None:
         self.azure_api_: AzureApi | None = None
         self.context = context
         self.tags = {"component": "context"} | context.tags
+        try:
+            if self.azure_api.subscription_id:
+                pass
+        except Exception as exc:
+            msg = "Not logged in or login has expired. \nAuthenticate using az login before creating or tearing down context infrastructure."
+            raise DataSafeHavenAzureError(msg) from exc
 
     @property
     def azure_api(self) -> AzureApi:

data_safe_haven/external/api/azure_api.py

@@ -845,6 +845,11 @@ def remove_resource_group(self, resource_group_name: str) -> None:
             self.logger.debug(
                 f"Removing resource group [green]{resource_group_name}[/] if it exists...",
             )
+            if not resource_client.resource_groups.check_existence(resource_group_name):
+                self.logger.error(
+                    f"Resource group [green]{resource_group_name}[/] does not exist. There is no context infrastructure to teardown.",
+                )
+                return
             poller = resource_client.resource_groups.begin_delete(
                 resource_group_name,
             )