faasd/cmd/collect.go
Alex Ellis (OpenFaaS Ltd) 2307fc71c5 Add log shim and collect command
The collect command redirects function logs to the journal for
viewing on journalctl. faas-cli logs is not implemented as of
yet. View logs with journalctl -t openfaas-fn:FN_NAME_HERE.

Tested on Dell XPS with Ubuntu Linux. The approach takes
inspiration from the Stellar project.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>
2020-02-23 19:54:49 +00:00

61 lines
1.3 KiB
Go

package cmd
import (
"bufio"
"context"
"fmt"
"io"
"sync"
"github.com/containerd/containerd/runtime/v2/logging"
"github.com/coreos/go-systemd/journal"
"github.com/spf13/cobra"
)
func CollectCommand() *cobra.Command {
return collectCmd
}
var collectCmd = &cobra.Command{
Use: "collect",
Short: "Collect logs to the journal",
RunE: runCollect,
}
func runCollect(_ *cobra.Command, _ []string) error {
logging.Run(logStdio)
return nil
}
// logStdio copied from
// https://github.com/containerd/containerd/pull/3085
// https://github.com/stellarproject/orbit
func logStdio(ctx context.Context, config *logging.Config, ready func() error) error {
// construct any log metadata for the container
vars := map[string]string{
"SYSLOG_IDENTIFIER": fmt.Sprintf("%s:%s", config.Namespace, config.ID),
}
var wg sync.WaitGroup
wg.Add(2)
// forward both stdout and stderr to the journal
go copy(&wg, config.Stdout, journal.PriInfo, vars)
go copy(&wg, config.Stderr, journal.PriErr, vars)
// signal that we are ready and setup for the container to be started
if err := ready(); err != nil {
return err
}
wg.Wait()
return nil
}
func copy(wg *sync.WaitGroup, r io.Reader, pri journal.Priority, vars map[string]string) {
defer wg.Done()
s := bufio.NewScanner(r)
for s.Scan() {
if s.Err() != nil {
return
}
journal.Send(s.Text(), pri, vars)
}
}