add grafana formatter

This was initially designed and implemented in #4

Co-authored-by: Sven Seeberg <mail@sven-seeberg.de>

matrix_webhook/formatters.py

@@ -0,0 +1,15 @@
+"""Formatters for matrix webhook."""
+
+
+def grafana(data):
+    """Pretty-print a grafana notification."""
+    text = ""
+    if "title" in data:
+        text = "### " + data["title"] + "\n"
+    if "message" in data:
+        text = text + data["message"] + "\n\n"
+    if "evalMatches" in data:
+        for match in data["evalMatches"]:
+            text = text + "* " + match["metric"] + ": " + str(match["value"]) + "\n"
+    data["body"] = text
+    return data