From 74d543824b16106ce7e0425b132f72e0f0f64919 Mon Sep 17 00:00:00 2001
From: Reid 'arrdem' McKenzie <me@arrdem.com>
Date: Sat, 20 Nov 2021 23:06:26 -0700
Subject: [PATCH] And done

---
 projects/aloe/README.md                   | 46 +++++++++++++++++++++++
 projects/aloe/src/python/aloe/__main__.py | 15 +++++---
 2 files changed, 56 insertions(+), 5 deletions(-)
 create mode 100644 projects/aloe/README.md

diff --git a/projects/aloe/README.md b/projects/aloe/README.md
new file mode 100644
index 0000000..bdbb7d5
--- /dev/null
+++ b/projects/aloe/README.md
@@ -0,0 +1,46 @@
+# Aloe
+
+> - A [cactus](https://www.cacti.net/)-like plant
+> - Traditionally used for a variety of skin conditions
+
+Aloe is a quick and dirty network weathermapping tool, much like MTR or Cacti.
+Aloe uses multiple threads to first establish a rough network topology via ICMP traceroutes, and then monitor it with ICMP pings.
+
+## Usage
+
+``` sh
+$ bazel build //projects/aloe
+$ sudo ./bazel-bin/projects/aloe/aloe twitter.com google.com
+```
+
+If hosts in topology stop responding for 10s or more (the polling interval is ~1s), they are declared to be warning.
+If hosts in topology stop responding for 5s, they are declared down.
+If a host in topology resume responding after 5s or more, they are declared to have recovered.
+If hosts in topology stop responding for 30 min, they are declared dead and monitoring is stopped.
+The topology is reconfigured every 5 min to account to DHCP and upstream changes.
+
+A log of all these events is built in a plain-text format to `incidents.txt`.
+The format of this file is -
+
+```
+UP        <ip>  <date>
+WARN      <ip>  <date>
+DOWN      <ip>  <date>
+RECOVERED <ip>  <date>   <duration>
+DEAD      <ip>  <date>   <duration>
+```
+
+## Future work
+
+- [ ] Log topology
+- [ ] Attempt to identify "root cause" incidents in the route graph which explain downstream failures
+- [ ] Use sqlite3 for aggregation not a plain text file
+- [ ] Use a more sophisticated counters and debounce model of host state in the main thread
+- [ ] Find some way to incorporate rolling counters (mean, median, stddev, deciles, max) into the UI
+- [ ] FFS find some way NOT to depend on that nonsense box-diagram service
+
+## License
+
+Copyright Reid 'arrdem' McKenzie, 11/20/2021.
+
+Published under the terms of the MIT license.
diff --git a/projects/aloe/src/python/aloe/__main__.py b/projects/aloe/src/python/aloe/__main__.py
index 2bde754..fb8e4ea 100644
--- a/projects/aloe/src/python/aloe/__main__.py
+++ b/projects/aloe/src/python/aloe/__main__.py
@@ -119,7 +119,7 @@ if __name__ == "__main__":
     flush_at = now + flush_delay
 
     recovered_duration = timedelta(seconds=5)
-    dead_duration = timedelta(seconds=30)
+    dead_duration = timedelta(minutes=30)
 
     topology = None
     id = unique_identifier()
@@ -159,29 +159,34 @@ if __name__ == "__main__":
             try:
                 timestamp, res = q.get(timeout=0.1)
                 last = last_seen.get(res.address)
+                delta = timestamp - last if last else None
 
                 if res.address not in workers:
                     pass
 
                 elif res.is_alive:
-                    if last and (delta := timestamp - last) > recovered_duration:
+                    last_seen[res.address] = timestamp
+                    if last and delta > recovered_duration:
                         fp.write(
                             f"RECOVERED\t{res.address}\t{timestamp.isoformat()}\t{delta.total_seconds()}\n"
                         )
                     elif not last:
                         fp.write(f"UP\t{res.address}\t{timestamp.isoformat()}\n")
-                    last_seen[res.address] = timestamp
 
                 elif not res.is_alive:
-                    if last and (delta := timestamp - last) > dead_duration:
+                    if last and delta > dead_duration:
                         workers[h.address].terminate()
                         del workers[h.address]
                         del topology[h.address]
+                        del last_seen[h.address]
                         fp.write(
                             f"DEAD\t{res.address}\t{timestamp.isoformat()}\t{delta.total_seconds()}\n"
                         )
 
-                    else:
+                    elif last and delta < recovered:
+                        fp.write(f"WARN\t{res.address}\t{timestamp.isoformat()}\n")
+
+                    elif last and delta > recovered:
                         fp.write(f"DOWN\t{res.address}\t{timestamp.isoformat()}\n")
 
             except queue.Empty: