| // 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" |
| "strconv" |
| "strings" |
| "time" |
| |
| apb "source.monogon.dev/metropolis/proto/api" |
| ) |
| |
| // LeveledPayload is a log entry for leveled logs (as per leveled.go). It contains |
| // the input to these calls (severity and message split into newline-delimited |
| // messages) and additional metadata that would be usually seen in a text |
| // representation of a leveled log entry. |
| type LeveledPayload struct { |
| // messages is the list of messages contained in this payload. This list is built |
| // from splitting up the given message from the user by newline. |
| messages []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 |
| } |
| |
| // String returns a canonical representation of this payload as a single string |
| // prefixed with metadata. If the original message was logged with newlines, this |
| // representation will also contain newlines, with each original message part |
| // prefixed by the metadata. For an alternative call that will instead return a |
| // canonical prefix and a list of lines in the message, see Strings(). |
| func (p *LeveledPayload) String() string { |
| prefix, lines := p.Strings() |
| res := make([]string, len(p.messages)) |
| for i, line := range lines { |
| res[i] = fmt.Sprintf("%s%s", prefix, line) |
| } |
| return strings.Join(res, "\n") |
| } |
| |
| // Strings returns the canonical representation of this payload split into a |
| // prefix and all lines that were contained in the original message. This is |
| // meant to be displayed to the user by showing the prefix before each line, |
| // concatenated together - possibly in a table form with the prefixes all |
| // unified with a rowspan- like mechanism. |
| // |
| // For example, this function can return: |
| // prefix = "I1102 17:20:06.921395 foo.go:42] " |
| // lines = []string{"current tags:", " - one", " - two"} |
| // |
| // With this data, the result should be presented to users this way in text form: |
| // I1102 17:20:06.921395 foo.go:42] current tags: |
| // I1102 17:20:06.921395 foo.go:42] - one |
| // I1102 17:20:06.921395 foo.go:42] - two |
| // |
| // Or, in a table layout: |
| // .-----------------------------------------------------------. |
| // | I1102 17:20:06.921395 0 foo.go:42] : current tags: | |
| // | :------------------| |
| // | : - one | |
| // | :------------------| |
| // | : - two | |
| // '-----------------------------------------------------------' |
| func (p *LeveledPayload) Strings() (prefix string, lines []string) { |
| _, month, day := p.timestamp.Date() |
| hour, minute, second := p.timestamp.Clock() |
| nsec := p.timestamp.Nanosecond() / 1000 |
| |
| // Same format as in glog, but without treadid. |
| // Lmmdd hh:mm:ss.uuuuuu file:line] |
| // TODO(q3k): rewrite this to printf-less code. |
| prefix = fmt.Sprintf("%s%02d%02d %02d:%02d:%02d.%06d %s:%d] ", p.severity, month, day, hour, minute, second, nsec, p.file, p.line) |
| |
| lines = p.messages |
| return |
| } |
| |
| // Message returns the inner message lines of this entry, ie. what was passed to |
| // the actual logging method, but split by newlines. |
| func (p *LeveledPayload) Messages() []string { return p.messages } |
| |
| func (p *LeveledPayload) MessagesJoined() string { return strings.Join(p.messages, "\n") } |
| |
| // Timestamp returns the time at which this entry was logged. |
| func (p *LeveledPayload) 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 *LeveledPayload) Location() string { return fmt.Sprintf("%s:%d", p.file, p.line) } |
| |
| // Severity returns the Severity with which this entry was logged. |
| func (p *LeveledPayload) Severity() Severity { return p.severity } |
| |
| // Proto converts a LeveledPayload to protobuf format. |
| func (p *LeveledPayload) Proto() *apb.LogEntry_Leveled { |
| return &apb.LogEntry_Leveled{ |
| Lines: p.Messages(), |
| Timestamp: p.Timestamp().UnixNano(), |
| Severity: p.Severity().ToProto(), |
| Location: p.Location(), |
| } |
| } |
| |
| // LeveledPayloadFromProto parses a protobuf message into the internal format. |
| func LeveledPayloadFromProto(p *apb.LogEntry_Leveled) (*LeveledPayload, error) { |
| severity, err := SeverityFromProto(p.Severity) |
| if err != nil { |
| return nil, fmt.Errorf("could not convert severity: %w", err) |
| } |
| parts := strings.Split(p.Location, ":") |
| if len(parts) != 2 { |
| return nil, fmt.Errorf("invalid location, must be two :-delimited parts, is %d parts", len(parts)) |
| } |
| file := parts[0] |
| line, err := strconv.Atoi(parts[1]) |
| if err != nil { |
| return nil, fmt.Errorf("invalid location line number: %w", err) |
| } |
| return &LeveledPayload{ |
| messages: p.Lines, |
| timestamp: time.Unix(0, p.Timestamp), |
| severity: severity, |
| file: file, |
| line: line, |
| }, nil |
| } |
| |
| // ExternalLeveledPayload is a LeveledPayload received from an external source, |
| // eg. from parsing the logging output of third-party programs. It can be |
| // converted into a LeveledPayload and inserted into a leveled logger, but will |
| // be sanitized before that, ensuring that potentially buggy |
| // emitters/converters do not end up polluting the leveled logger data. |
| // |
| // This type should be used only when inserting data from external systems, not |
| // by code that just wishes to log things. In the future, data inserted this |
| // way might be explicitly marked as tainted so operators can understand that |
| // parts of this data might not give the same guarantees as the log entries |
| // emitted by the native LeveledLogger API. |
| type ExternalLeveledPayload struct { |
| // Log line. If any newlines are found, they will split the message into |
| // multiple messages within LeveledPayload. Empty messages are accepted |
| // verbatim. |
| Message string |
| // Timestamp when this payload was emitted according to its source. If not |
| // given, will default to the time of conversion to LeveledPayload. |
| Timestamp time.Time |
| // Log severity. If invalid or unset will default to INFO. |
| Severity Severity |
| // File name of originating code. Defaults to "unknown" if not set. |
| File string |
| // Line in File. Zero indicates the line is not known. |
| Line int |
| } |
| |
| // sanitize the given ExternalLeveledPayload by creating a corresponding |
| // LeveledPayload. The original object is unaltered. |
| func (e *ExternalLeveledPayload) sanitize() *LeveledPayload { |
| l := &LeveledPayload{ |
| messages: strings.Split(e.Message, "\n"), |
| timestamp: e.Timestamp, |
| severity: e.Severity, |
| file: e.File, |
| line: e.Line, |
| } |
| if l.timestamp.IsZero() { |
| l.timestamp = time.Now() |
| } |
| if !l.severity.Valid() { |
| l.severity = INFO |
| } |
| if l.file == "" { |
| l.file = "unknown" |
| } |
| if l.line < 0 { |
| l.line = 0 |
| } |
| return l |
| } |