feat: serve an APPVERSIONS.json index file to clients via IMAP metadata

This is designed to help implement self-updating APKs (and later other clients),
see counterpart https://github.com/chatmail/core/pull/8557

cmdeploy/src/cmdeploy/deployers.py

@@ -35,7 +35,7 @@ from .nginx.deployer import NginxDeployer
 from .opendkim.deployer import OpendkimDeployer
 from .postfix.deployer import PostfixDeployer
 from .selfsigned.deployer import SelfSignedTlsDeployer
-from .www import build_webpages, find_merge_conflict, get_paths
+from .www import build_webpages, find_merge_conflict, get_paths, get_reporoot
 
 
 class Port(FactBase):
@@ -126,6 +126,11 @@ def _configure_remote_venv_with_chatmaild(deployer, config) -> None:
         dest=remote_chatmail_inipath,
     )
 
+    deployer.put_file(
+        src=get_reporoot().joinpath("APPVERSIONS.json").open("rb"),
+        dest=str(config.appversions_path),
+    )
+
     deployer.remove_file("/etc/cron.d/chatmail-metrics")
     deployer.remove_file("/var/www/html/metrics")
 

cmdeploy/src/cmdeploy/tests/online/test_2_deltachat.py

@@ -51,6 +51,16 @@ class TestMetadataTokens:
         assert res == b"1111 2222"
         assert b"Getmetadata completed" in client.readline()
 
+    def test_get_appversions(self, imap_mailbox):
+        "get app version information shipped with the relay"
+        client = imap_mailbox.client
+        client.send(b'a01 GETMETADATA "" /shared/vendor/deltachat/appversions\n')
+        res = client.readline()
+        assert res[:1] == b"*"
+        res = client.readline().strip().rstrip(b")")
+        assert b'"clients":' in res
+        assert b"Getmetadata completed" in client.readline()
+
 
 class TestEndToEndDeltaChat:
     "Tests that use Delta Chat accounts on the chat mail instance."

cmdeploy/src/cmdeploy/tests/test_appversions.py

@@ -0,0 +1,20 @@
+import json
+
+from cmdeploy.www import get_reporoot
+
+ALLOWED_URL_PREFIXES = (
+    "https://github.com/deltachat/",
+    "https://download.delta.chat/",
+)
+
+
+def test_appversions_schema():
+    data = json.loads(get_reporoot().joinpath("APPVERSIONS.json").read_text())
+    assert data["clients"]
+    for client in data["clients"]:
+        assert isinstance(client["clientId"], str)
+        for source in client["sources"]:
+            assert isinstance(source["sourceId"], str)
+            assert isinstance(source["versionInteger"], int)
+            assert isinstance(source["versionString"], str)
+            assert source["downloadUrl"].startswith(ALLOWED_URL_PREFIXES)

cmdeploy/src/cmdeploy/www.py

@@ -35,8 +35,12 @@ def prepare_template(source):
     return render_vars, page_layout
 
 
+def get_reporoot() -> Path:
+    return (Path(__file__).resolve() / "../../../../").resolve()
+
+
 def get_paths(config) -> (Path, Path, Path):
-    reporoot = (Path(__file__).resolve() / "../../../../").resolve()
+    reporoot = get_reporoot()
     www_path = Path(config.www_folder)
     # if www_folder was not set, use default directory
     if config.www_folder == "":