mirror of
https://github.com/Luzifer/go-latestver.git
synced 2024-12-21 02:51:17 +00:00
96 lines
2.6 KiB
Go
96 lines
2.6 KiB
Go
package fetcher
|
|
|
|
import (
|
|
"context"
|
|
"io/ioutil"
|
|
"net/http"
|
|
"regexp"
|
|
"time"
|
|
|
|
"github.com/pkg/errors"
|
|
|
|
"github.com/Luzifer/go-latestver/internal/database"
|
|
"github.com/Luzifer/go_helpers/v2/fieldcollection"
|
|
)
|
|
|
|
/*
|
|
* @module regex
|
|
* @module_desc Fetches URL and applies a regular expression to extract a version from it
|
|
*/
|
|
|
|
const (
|
|
httpStatus3xx = 300
|
|
regexpFetcherExpectedLength = 2
|
|
)
|
|
|
|
type (
|
|
RegexFetcher struct{}
|
|
)
|
|
|
|
func init() { registerFetcher("regex", func() Fetcher { return &RegexFetcher{} }) }
|
|
|
|
func (h RegexFetcher) FetchVersion(ctx context.Context, attrs *fieldcollection.FieldCollection) (string, time.Time, error) {
|
|
req, err := http.NewRequestWithContext(ctx, http.MethodGet, attrs.MustString("url", nil), nil)
|
|
if err != nil {
|
|
return "", time.Time{}, errors.Wrap(err, "creating request")
|
|
}
|
|
|
|
resp, err := http.DefaultClient.Do(req)
|
|
if err != nil {
|
|
return "", time.Time{}, errors.Wrap(err, "executing request")
|
|
}
|
|
defer resp.Body.Close()
|
|
|
|
if resp.StatusCode >= httpStatus3xx {
|
|
return "", time.Time{}, errors.Errorf("HTTP status %d", resp.StatusCode)
|
|
}
|
|
|
|
data, err := ioutil.ReadAll(resp.Body)
|
|
if err != nil {
|
|
return "", time.Time{}, errors.Wrap(err, "reading response body")
|
|
}
|
|
|
|
matches := regexp.MustCompile(attrs.MustString("regex", nil)).FindStringSubmatch(string(data))
|
|
if matches == nil {
|
|
return "", time.Time{}, errors.New("regex did not match the response")
|
|
}
|
|
|
|
if l := len(matches); l != regexpFetcherExpectedLength {
|
|
return "", time.Time{}, errors.Errorf("unpexected number of matches: %d != 2", l)
|
|
}
|
|
|
|
return matches[1], time.Now(), nil
|
|
}
|
|
|
|
func (h RegexFetcher) Links(attrs *fieldcollection.FieldCollection) []database.CatalogLink {
|
|
return []database.CatalogLink{
|
|
{
|
|
IconClass: "fas fa-globe",
|
|
Name: "Website",
|
|
URL: attrs.MustString("url", nil),
|
|
},
|
|
}
|
|
}
|
|
|
|
func (h RegexFetcher) Validate(attrs *fieldcollection.FieldCollection) error {
|
|
// @attr url required string "" URL to fetch the content from
|
|
if v, err := attrs.String("url"); err != nil || v == "" {
|
|
return errors.New("url is expected to be non-empty string")
|
|
}
|
|
|
|
// @attr regex required string "" Regular expression (RE2) to apply to the text fetched from the URL. The regex MUST have exactly one submatch containing the version.
|
|
if v, err := attrs.String("regex"); err != nil || v == "" {
|
|
return errors.New("regex is expected to be non-empty string")
|
|
}
|
|
|
|
r, err := regexp.Compile(attrs.MustString("regex", nil))
|
|
if err != nil {
|
|
return errors.Wrap(err, "compiling regex expression")
|
|
}
|
|
|
|
if n := r.NumSubexp(); n != 1 {
|
|
return errors.Errorf("regex must have 1 submatch, has %d", n)
|
|
}
|
|
|
|
return nil
|
|
}
|