logtree: implement
This implements logtree, as per go/logtree .
Some API changes are present, the design doc will be updated to reflect
these and the rationale behind the changes.
This implementation is missing 'raw' log functionality, this will be
added in a diff on top (as the implementation is trivial, but we want
to keep this diff as simple as possible).
Test Plan: covered by tests
X-Origin-Diff: phab/D624
GitOrigin-RevId: 6d1e0fb16f47e4b0dc9a18765cecb9314bbcb441
diff --git a/core/pkg/logtree/payload.go b/core/pkg/logtree/payload.go
new file mode 100644
index 0000000..c6707e9
--- /dev/null
+++ b/core/pkg/logtree/payload.go
@@ -0,0 +1,64 @@
+// 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 (
+ "fmt"
+ "time"
+)
+
+// Payload is a log entry for leveled logs (as per leveled.go). It contains not only the log message itself and its
+// severity, but also additional metadata that would be usually seen in a text representation of a leveled log entry.
+type Payload struct {
+ // message is the log message, rendered from a leveled log call like Infof(), Warningf(), ...
+ message string
+ // timestamp is the time at which this message was emitted.
+ timestamp time.Time
+ // severity is the leveled Severity at which this message was emitted.
+ severity Severity
+ // file is the filename of the caller that emitted this message.
+ file string
+ // line is the line number within the file of the caller that emitted this message.
+ line int
+}
+
+func (p *Payload) String() string {
+ // Same format as in glog:
+ // Lmmdd hh:mm:ss.uuuuuu threadid file:line]
+ // Except, threadid is (currently) always zero. In the future this field might be used for something different.
+
+ _, month, day := p.timestamp.Date()
+ hour, minute, second := p.timestamp.Clock()
+ nsec := p.timestamp.Nanosecond() / 1000
+
+ // TODO(q3k): rewrite this to printf-less code.
+ return fmt.Sprintf("%s%02d%02d %02d:%02d:%02d.%06d % 7d %s:%d] %s", p.severity, month, day, hour, minute, second,
+ nsec, 0, p.file, p.line, p.message)
+}
+
+// Message returns the inner message of this entry, ie. what was passed to the actual logging method.
+func (p *Payload) Message() string { return p.message }
+
+// Timestamp returns the time at which this entry was logged.
+func (p *Payload) Timestamp() time.Time { return p.timestamp }
+
+// Location returns a string in the form of file_name:line_number that shows the origin of the log entry in the
+// program source.
+func (p *Payload) Location() string { return fmt.Sprintf("%s:%d", p.file, p.line) }
+
+// Severity returns the Severity with which this entry was logged.
+func (p *Payload) Severity() Severity { return p.severity }