m/pkg/logtree: implement klog parsing
This adds logtree.KLogParser, a shim which parses klog/glog-formatted
lines into logtree leveled logging.
This will be used to consume logs from external components (like
Kubernetes services) into leveled logging inside logtree.
An alternative would be to switch all Kubernetes components to
'structured' (JSON) logging - but that seems to still be experimental,
and does not exactly map into something that we can log further. Maybe
in the future we can switch over, and also copy these over into our own
binary/structured logging.
Test Plan: Adds unit tests for parsing, which is the most tricky part.
X-Origin-Diff: phab/D715
GitOrigin-RevId: 9994d819f15c9542800d488f57c83ab945a35d34
diff --git a/metropolis/pkg/logtree/klog_test.go b/metropolis/pkg/logtree/klog_test.go
new file mode 100644
index 0000000..f163f16
--- /dev/null
+++ b/metropolis/pkg/logtree/klog_test.go
@@ -0,0 +1,82 @@
+// Copyright 2020 The Monogon Project Authors.
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package logtree
+
+import (
+ "testing"
+ "time"
+
+ "github.com/google/go-cmp/cmp"
+)
+
+func TestParse(t *testing.T) {
+ // Injected 'now'. Used to make these tests reproducible and to allow for
+ // testing the log-across-year edgecase.
+ // Fri 12 Mar 2021 03:46:26 PM UTC
+ now := time.Unix(1615563986, 123456789)
+ // Sat 01 Jan 2000 12:00:01 AM UTC
+ nowNewYear := time.Unix(946684801, 0)
+
+ for i, te := range []struct{
+ now time.Time
+ line string
+ want *LeveledPayload
+ }{
+ // 0: Simple case: everything should parse correctly.
+ { now, "E0312 14:20:04.240540 204 shared_informer.go:247] Caches are synced for attach detach", &LeveledPayload{
+ messages: []string{"Caches are synced for attach detach"},
+ timestamp: time.Date(2021, 03, 12, 14, 20, 4, 240540000, time.UTC),
+ severity: ERROR,
+ file: "shared_informer.go",
+ line: 247,
+ } },
+ // 1: Mumbling line, should fail.
+ { now, "Application starting up...", nil},
+ // 2: Empty line, should fail.
+ { now, "", nil},
+ // 3: Line from the future, should fail.
+ { now, "I1224 14:20:04.240540 204 john_titor.go:247] I'm sorry, what day is it today? Uuuh, and what year?", nil },
+ // 4: Log-across-year edge case. The log was emitted right before a year
+ // rollover, and parsed right after it. It should be attributed to the
+ // previous year.
+ { nowNewYear, "I1231 23:59:43.123456 123 fry.go:123] Here's to another lousy millenium!", &LeveledPayload{
+ messages: []string{"Here's to another lousy millenium!"},
+ timestamp: time.Date(1999, 12, 31, 23, 59, 43, 123456000, time.UTC),
+ severity: INFO,
+ file: "fry.go",
+ line: 123,
+ }},
+ // 5: Invalid severity, should fail.
+ { now, "D0312 14:20:04.240540 204 shared_informer.go:247] Caches are synced for attach detach", nil },
+ // 6: Invalid time, should fail.
+ { now, "D0312 25:20:04.240540 204 shared_informer.go:247] Caches are synced for attach detach", nil },
+ // 7: Simple case without sub-second timing: everything should parse correctly
+ { now, "E0312 14:20:04 204 shared_informer.go:247] Caches are synced for attach detach", &LeveledPayload{
+ messages: []string{"Caches are synced for attach detach"},
+ timestamp: time.Date(2021, 03, 12, 14, 20, 4, 0, time.UTC),
+ severity: ERROR,
+ file: "shared_informer.go",
+ line: 247,
+ } },
+ } {
+ got := parse(te.now, te.line)
+ if diff := cmp.Diff(te.want, got, cmp.AllowUnexported(LeveledPayload{})); diff != "" {
+ t.Errorf("%d: mismatch (-want +got):\n%s", i, diff)
+ }
+ }
+}
+