122 lines
3.2 KiB
Go
122 lines
3.2 KiB
Go
package core
|
|
|
|
import (
|
|
"fmt"
|
|
"io"
|
|
"log"
|
|
"os"
|
|
"os/exec"
|
|
"sort"
|
|
"strings"
|
|
)
|
|
|
|
var IntakeCronBegin = "### begin intake-managed crontab entries"
|
|
var IntakeCronEnd = "### end intake-managed crontab entries"
|
|
|
|
func makeCrontabEntry(source string, spec string) string {
|
|
// TODO the /etc/profile setup is NixOS-specific, maybe there's another way to do this
|
|
return fmt.Sprintf("%-20s . /etc/profile; intake source fetch -s %s", spec, source)
|
|
}
|
|
|
|
func GetCronSources(db DB) (specs map[string]string, err error) {
|
|
res, err := db.Query(`
|
|
select source, value
|
|
from envs
|
|
where name = 'INTAKE_CRON'
|
|
`)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("failed to get source crontabs: %v", err)
|
|
}
|
|
specs = make(map[string]string)
|
|
for res.Next() {
|
|
var source string
|
|
var value string
|
|
if err = res.Scan(&source, &value); err != nil {
|
|
return nil, fmt.Errorf("failed to scan source crontab: %v", err)
|
|
}
|
|
specs[source] = makeCrontabEntry(source, value)
|
|
}
|
|
return
|
|
}
|
|
|
|
// Update the intake-managed section of the user's crontab.
|
|
func UpdateCrontab(db DB, specs map[string]string) (err error) {
|
|
// If there is no crontab command available, quit early.
|
|
crontabPath, err := exec.LookPath("crontab")
|
|
if err != nil {
|
|
return fmt.Errorf("no crontab found")
|
|
}
|
|
|
|
// Get the current crontab without extra header lines via `EDITOR=cat crontab -e`
|
|
cmdLoad := exec.Command(crontabPath, "-e")
|
|
cmdLoad.Env = append(os.Environ(), "EDITOR=cat")
|
|
output, err := cmdLoad.Output()
|
|
if err != nil {
|
|
return fmt.Errorf("error: failed to get current crontab: %v", err)
|
|
}
|
|
lines := strings.Split(string(output), "\n")
|
|
|
|
// Sort the new intake crons
|
|
var sources []string
|
|
for source := range specs {
|
|
sources = append(sources, source)
|
|
}
|
|
sort.Strings(sources)
|
|
|
|
// Splice the intake crons into the crontab
|
|
var newCrontab []string
|
|
headerFound := false
|
|
inSection := false
|
|
for i := range lines {
|
|
switch {
|
|
case !headerFound && lines[i] == IntakeCronBegin:
|
|
headerFound = true
|
|
inSection = true
|
|
newCrontab = append(newCrontab, IntakeCronBegin)
|
|
for _, source := range sources {
|
|
newCrontab = append(newCrontab, specs[source])
|
|
}
|
|
|
|
case lines[i] == IntakeCronEnd:
|
|
newCrontab = append(newCrontab, IntakeCronEnd)
|
|
inSection = false
|
|
|
|
case !inSection:
|
|
newCrontab = append(newCrontab, lines[i])
|
|
}
|
|
}
|
|
|
|
// If the splice mark was never found, append the whole section to the end
|
|
if !headerFound {
|
|
newCrontab = append(newCrontab, IntakeCronBegin)
|
|
for _, source := range sources {
|
|
newCrontab = append(newCrontab, specs[source])
|
|
}
|
|
newCrontab = append(newCrontab, IntakeCronEnd)
|
|
}
|
|
|
|
log.Printf("Updating %d crontab entries", len(specs))
|
|
|
|
// Save the updated crontab
|
|
cmdSave := exec.Command(crontabPath, "-")
|
|
stdin, err := cmdSave.StdinPipe()
|
|
if err != nil {
|
|
return fmt.Errorf("failed to open stdin: %v", err)
|
|
}
|
|
if _, err := io.WriteString(stdin, strings.Join(newCrontab, "\n")); err != nil {
|
|
return fmt.Errorf("failed to write to crontab: %v", err)
|
|
}
|
|
if err := stdin.Close(); err != nil {
|
|
return fmt.Errorf("failed to close stdin: %v", err)
|
|
}
|
|
output, err = cmdSave.CombinedOutput()
|
|
if err != nil {
|
|
log.Printf("failed to read crontab output: %v", err)
|
|
}
|
|
if len(output) > 0 {
|
|
log.Printf("crontab output: %s", string(output))
|
|
}
|
|
|
|
return nil
|
|
}
|