feat: [CDE-127]: Adding changes to include logging in container orche…

…stration. (harness#2178)

* feat: [CDE-127]: Linting.
* Merge branch 'refs/heads/main' into CDE-127

# Conflicts:
#	app/gitspace/orchestrator/container/embedded_docker.go
#	cmd/gitness/wire.go
* feat: [CDE-127]: Addressing review comments.
* feat: [CDE-127]: Removing streams map from StatefulLogger. Flushing the stream every time the invoking function is closed.
* feat: [CDE-127]: Removing streams map from StatefulLogger. Flushing the stream every time the invoking function is closed.
* feat: [CDE-127]: Removing streams map from StatefulLogger. Flushing the stream every time the invoking function is closed.
* feat: [CDE-127]: Removing streams map from StatefulLogger. Flushing the stream every time the invoking function is closed.
* feat: [CDE-127]: Adding flush stream logic to delete gitspace in orchestrator. Linting.
* feat: [CDE-127]: Adding flush stream logic to delete gitspace in orchestrator. Linting.
* feat: [CDE-127]: Addressing review comments.
* feat: [CDE-127]: Adding changes to make logutil.StatefulLogger a wrapper on livelog.LogStream and adding initialisation and flush functions.
* feat: [CDE-127]: Adding changes to make logutil.StatefulLogger a wrapper on livelog.LogStream and adding initialisation and flush functions.
* feat: [CDE-127]: Adding changes to include logging in container orchestration's stop flow.
* feat: [CDE-127]: Adding changes to include logging in container orchestration's start flow.

app/gitspace/logutil/reusable_scanner.go

@@ -0,0 +1,50 @@
+// Copyright 2023 Harness, Inc.
+//
+// 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 logutil
+
+import (
+	"bufio"
+	"fmt"
+	"strings"
+)
+
+type reusableScanner struct {
+	scanner *bufio.Scanner
+	reader  *strings.Reader
+}
+
+func newReusableScanner() *reusableScanner {
+	reader := strings.NewReader("")
+	scanner := bufio.NewScanner(reader)
+	return &reusableScanner{
+		scanner: scanner,
+		reader:  reader,
+	}
+}
+
+func (r *reusableScanner) scan(input string) ([]string, error) {
+	r.reader.Reset(input)
+	var lines []string
+
+	for r.scanner.Scan() {
+		lines = append(lines, r.scanner.Text())
+	}
+
+	if err := r.scanner.Err(); err != nil {
+		return nil, fmt.Errorf("error reading string %s: %w", input, err)
+	}
+
+	return lines, nil
+}

app/gitspace/logutil/stateful_logger.go

@@ -0,0 +1,106 @@
+// Copyright 2023 Harness, Inc.
+//
+// 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 logutil
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/harness/gitness/livelog"
+)
+
+const offset int64 = 1000000000
+
+// StatefulLogger is a wrapper on livelog.Logstream. It is used to create stateful instances of LogStreamInstance.
+type StatefulLogger struct {
+	logz livelog.LogStream
+}
+
+// LogStreamInstance is a stateful instance of the livelog.LogStream. It keeps track of the position & log key (id).
+type LogStreamInstance struct {
+	ctx      context.Context
+	id       int64
+	offsetID int64
+	position int
+	scanner  *reusableScanner
+	logz     livelog.LogStream
+}
+
+func NewStatefulLogger(logz livelog.LogStream) *StatefulLogger {
+	return &StatefulLogger{
+		logz: logz,
+	}
+}
+
+// GetLogStream returns an instance of LogStreamInstance tied to the given id.
+func (s *StatefulLogger) CreateLogStream(ctx context.Context, id int64) (*LogStreamInstance, error) {
+	// TODO: As livelog.LogStreamInstance uses only a single id as key, conflicts are likely if pipelines and gitspaces
+	// are used in the same instance of Gitness. We need to update the underlying implementation to use another unique
+	// key. To avoid that, we offset the ID by offset (1000000000).
+	offsetID := offset + id
+
+	// Create new logstream
+	err := s.logz.Create(ctx, offsetID)
+	if err != nil {
+		return nil, fmt.Errorf("error creating log stream for ID %d: %w", id, err)
+	}
+
+	newStream := &LogStreamInstance{
+		id:       id,
+		offsetID: offsetID,
+		ctx:      ctx,
+		scanner:  newReusableScanner(),
+		logz:     s.logz,
+	}
+
+	return newStream, nil
+}
+
+// Write writes the msg into the underlying log stream.
+func (l *LogStreamInstance) Write(msg string) error {
+	lines, err := l.scanner.scan(msg)
+	if err != nil {
+		return fmt.Errorf("error parsing log lines %s: %w", msg, err)
+	}
+
+	for _, line := range lines {
+		err = l.logz.Write(
+			l.ctx,
+			l.offsetID,
+			&livelog.Line{
+				Number:    l.position,
+				Message:   line,
+				Timestamp: time.Now().UnixMilli(),
+			})
+		if err != nil {
+			return fmt.Errorf("could not write log %s for ID %d at pos %d: %w", line, l.id, l.position, err)
+		}
+
+		l.position++
+	}
+
+	return nil
+}
+
+// Flush deletes the underlying stream.
+func (l *LogStreamInstance) Flush() error {
+	err := l.logz.Delete(l.ctx, l.offsetID)
+	if err != nil {
+		return fmt.Errorf("failed to delete old log stream for ID %d: %w", l.id, err)
+	}
+
+	return nil
+}

app/gitspace/logutil/wire.go

@@ -0,0 +1,29 @@
+// Copyright 2023 Harness, Inc.
+//
+// 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 logutil
+
+import (
+	"github.com/harness/gitness/livelog"
+
+	"github.com/google/wire"
+)
+
+var WireSet = wire.NewSet(
+	ProvideStatefulLogger,
+)
+
+func ProvideStatefulLogger(logz livelog.LogStream) *StatefulLogger {
+	return NewStatefulLogger(logz)
+}