9e0af86775
Shorter and clearer error types. - InvalidParameterError is now RefError. It is returned when a ref (the new ref or the parent ref) is invalid. - The ResolveRefError is not renamed. It is returned when a ref can't be resolved (e.g., ref not found at URL). New error type ParameterComboError. It is returned when a parent ref is specified but no URL, which is an invalid parameter combination.
97 lines
3 KiB
Go
97 lines
3 KiB
Go
package ostree
|
|
|
|
import (
|
|
"encoding/hex"
|
|
"io/ioutil"
|
|
"net/http"
|
|
"net/url"
|
|
"path"
|
|
"regexp"
|
|
"strings"
|
|
)
|
|
|
|
var ostreeRefRE = regexp.MustCompile(`^(?:[\w\d][-._\w\d]*\/)*[\w\d][-._\w\d]*$`)
|
|
|
|
type RequestParams struct {
|
|
URL string `json:"url"`
|
|
Ref string `json:"ref"`
|
|
Parent string `json:"parent"`
|
|
}
|
|
|
|
func VerifyRef(ref string) bool {
|
|
return len(ref) > 0 && ostreeRefRE.MatchString(ref)
|
|
}
|
|
|
|
// ResolveRef resolves the URL path specified by the location and ref
|
|
// (location+"refs/heads/"+ref) and returns the commit ID for the named ref. If
|
|
// there is an error, it will be of type ResolveRefError.
|
|
func ResolveRef(location, ref string) (string, error) {
|
|
u, err := url.Parse(location)
|
|
if err != nil {
|
|
return "", NewResolveRefError(err.Error())
|
|
}
|
|
u.Path = path.Join(u.Path, "refs/heads/", ref)
|
|
resp, err := http.Get(u.String())
|
|
if err != nil {
|
|
return "", NewResolveRefError(err.Error())
|
|
}
|
|
if resp.StatusCode != http.StatusOK {
|
|
return "", NewResolveRefError("ostree repository %q returned status: %s", u.String(), resp.Status)
|
|
}
|
|
body, err := ioutil.ReadAll(resp.Body)
|
|
if err != nil {
|
|
return "", NewResolveRefError(err.Error())
|
|
}
|
|
parent := strings.TrimSpace(string(body))
|
|
// Check that this is at least a hex string.
|
|
_, err = hex.DecodeString(parent)
|
|
if err != nil {
|
|
return "", NewResolveRefError("ostree repository %q returned invalid reference", u.String())
|
|
}
|
|
return parent, nil
|
|
}
|
|
|
|
// ResolveParams resolves all necessary missing parameters in the given struct:
|
|
// it sets the defaultRef if none is provided and resolves the parent commit if
|
|
// a URL and Ref are provided. If there is an error, it will be of type
|
|
// InvalidParameterError or ResolveRefError (from the ResolveRef function)
|
|
func ResolveParams(params RequestParams, defaultRef string) (RequestParams, error) {
|
|
resolved := RequestParams{}
|
|
resolved.Ref = params.Ref
|
|
// if ref is not provided, use distro default
|
|
if resolved.Ref == "" {
|
|
resolved.Ref = defaultRef
|
|
} else if !VerifyRef(params.Ref) { // only verify if specified in params
|
|
return resolved, NewRefError("Invalid ostree ref %q", params.Ref)
|
|
}
|
|
|
|
if params.Parent != "" {
|
|
// parent must also be a valid ref
|
|
if !VerifyRef(params.Parent) {
|
|
return resolved, NewRefError("Invalid ostree parent ref %q", params.Parent)
|
|
}
|
|
if params.URL == "" {
|
|
// specifying parent ref also requires URL
|
|
return resolved, NewParameterComboError("ostree parent ref specified, but no URL to retrieve it")
|
|
}
|
|
}
|
|
|
|
resolved.URL = params.URL
|
|
if resolved.URL != "" {
|
|
// if a URL is specified, we need to fetch the commit at the URL
|
|
// the reference to resolve is the parent commit which is defined by
|
|
// the 'parent' argument
|
|
// if the parent argument is not specified, we use the specified ref
|
|
// if neither is specified, we use the default ref
|
|
parentRef := params.Parent
|
|
if parentRef == "" {
|
|
parentRef = resolved.Ref
|
|
}
|
|
parent, err := ResolveRef(resolved.URL, parentRef)
|
|
if err != nil {
|
|
return resolved, err // ResolveRefError
|
|
}
|
|
resolved.Parent = parent
|
|
}
|
|
return resolved, nil
|
|
}
|