lemmy-reply-bot/config.go

112 lines
2.4 KiB
Go

package main
import (
"net/url"
"os"
"strconv"
"text/template"
"time"
"github.com/Masterminds/sprig"
"github.com/pelletier/go-toml/v2"
"go.elara.ws/logger/log"
"go.elara.ws/pcre"
)
type ConfigFile struct {
Lemmy struct {
InstanceURL string `toml:"instanceURL"`
Account struct {
UserOrEmail string `toml:"userOrEmail"`
Password string `toml:"password"`
} `toml:"account"`
} `toml:"lemmy"`
Replies []Reply `toml:"reply"`
}
type Reply struct {
Regex string `toml:"regex"`
Msg string `toml:"msg"`
}
type Config struct {
ConfigFile *ConfigFile
Regexes map[string]*pcre.Regexp
Tmpls map[string]*template.Template
PollInterval time.Duration
}
func loadConfig(path string) (Config, error) {
fi, err := os.Stat(path)
if err != nil {
return Config{}, err
}
if fi.Mode().Perm() != 0o600 {
log.Fatal("Your config file's permissions are insecure. Please use chmod to set them to 600. Refusing to start.").Send()
}
fl, err := os.Open(path)
if err != nil {
return Config{}, err
}
cfgFile := &ConfigFile{}
err = toml.NewDecoder(fl).Decode(cfgFile)
if err != nil {
return Config{}, err
}
compiledRegexes, compiledTmpls, err := compileReplies(cfgFile.Replies)
if err != nil {
return Config{}, err
}
cfg := Config{cfgFile, compiledRegexes, compiledTmpls, 15 * time.Second}
validateConfig(cfg)
return cfg, nil
}
func compileReplies(replies []Reply) (map[string]*pcre.Regexp, map[string]*template.Template, error) {
compiledRegexes := map[string]*pcre.Regexp{}
compiledTmpls := map[string]*template.Template{}
for i, reply := range replies {
if _, ok := compiledRegexes[reply.Regex]; ok {
continue
}
re, err := pcre.Compile(reply.Regex)
if err != nil {
return nil, nil, err
}
compiledRegexes[reply.Regex] = re
tmpl, err := template.
New(strconv.Itoa(i)).
Funcs(sprig.TxtFuncMap()).
Parse(reply.Msg)
if err != nil {
return nil, nil, err
}
compiledTmpls[reply.Regex] = tmpl
}
return compiledRegexes, compiledTmpls, nil
}
func validateConfig(cfg Config) {
_, err := url.Parse(cfg.ConfigFile.Lemmy.InstanceURL)
if err != nil {
log.Fatal("Lemmy instance URL is not valid").Err(err).Send()
}
for i, reply := range cfg.ConfigFile.Replies {
re := cfg.Regexes[reply.Regex]
if re.MatchString(reply.Msg) {
log.Fatal("Regular expression matches message. This may create an infinite loop. Refusing to start.").Int("reply-index", i).Send()
}
}
}