claw
217bc60084
- escapePath now returns an error when paths contain dot-segments
(".", "..") instead of silently rewriting them. This prevents
subtle API misses where callers pass "foo/../bar" expecting to
hit "bar" but the old code produced "foo/bar".
- Uses path.Clean for canonical form after validation.
- CommitStatus.Description for check runs is now empty string
instead of the raw conclusion enum. The conclusion is already
captured in the Status field via mapCheckRunStatus; storing it
again in Description was semantically inconsistent with commit
statuses where Description carries a human-readable narrative.
- Removed unused derefString helper.
- Added tests for escapePath valid paths, dot-segment rejection,
and GetFileContentAtRef dot-segment error propagation.
88 lines
2.8 KiB
Go
88 lines
2.8 KiB
Go
package github
|
|
|
|
import (
|
|
"context"
|
|
"encoding/base64"
|
|
"encoding/json"
|
|
"fmt"
|
|
"net/url"
|
|
"path"
|
|
"strings"
|
|
)
|
|
|
|
// GetFileContentAtRef fetches a file at a specific ref from a repo.
|
|
// If ref is empty, the query parameter is omitted (uses default branch).
|
|
//
|
|
// Returns an error if the path contains dot-segments (".", "..") or
|
|
// attempts to traverse above the repository root.
|
|
func (c *Client) GetFileContentAtRef(ctx context.Context, owner, repo, filePath, ref string) (string, error) {
|
|
escaped, err := escapePath(filePath)
|
|
if err != nil {
|
|
return "", fmt.Errorf("invalid file path: %w", err)
|
|
}
|
|
reqURL := fmt.Sprintf("%s/repos/%s/%s/contents/%s",
|
|
c.baseURL, url.PathEscape(owner), url.PathEscape(repo), escaped)
|
|
if ref != "" {
|
|
reqURL += "?ref=" + url.QueryEscape(ref)
|
|
}
|
|
body, err := c.doGet(ctx, reqURL)
|
|
if err != nil {
|
|
return "", fmt.Errorf("fetch file %s: %w", filePath, err)
|
|
}
|
|
var resp struct {
|
|
Content string `json:"content"`
|
|
Encoding string `json:"encoding"`
|
|
}
|
|
if err := json.Unmarshal(body, &resp); err != nil {
|
|
return "", fmt.Errorf("parse file content JSON: %w", err)
|
|
}
|
|
if resp.Encoding != "base64" {
|
|
return "", fmt.Errorf("unexpected encoding %q for file %s", resp.Encoding, filePath)
|
|
}
|
|
decoded, err := decodeBase64Content(resp.Content)
|
|
if err != nil {
|
|
return "", fmt.Errorf("decode base64 content for %s: %w", filePath, err)
|
|
}
|
|
return decoded, nil
|
|
}
|
|
|
|
// escapePath validates and encodes a slash-separated file path for use in
|
|
// GitHub API URLs. Returns an error if the path contains dot-segments ("."
|
|
// or "..") or resolves to a path outside the repository root.
|
|
func escapePath(p string) (string, error) {
|
|
// Reject paths containing dot-segments rather than silently rewriting them.
|
|
for _, seg := range strings.Split(p, "/") {
|
|
if seg == "." || seg == ".." {
|
|
return "", fmt.Errorf("path contains dot-segment %q: %s", seg, p)
|
|
}
|
|
}
|
|
|
|
// Use path.Clean for canonical form, then verify it doesn't escape root.
|
|
cleaned := path.Clean(p)
|
|
if cleaned == "." || strings.HasPrefix(cleaned, "..") {
|
|
return "", fmt.Errorf("path resolves outside repository root: %s", p)
|
|
}
|
|
|
|
// Encode each segment individually.
|
|
parts := strings.Split(cleaned, "/")
|
|
var encoded []string
|
|
for _, part := range parts {
|
|
if part == "" {
|
|
continue
|
|
}
|
|
encoded = append(encoded, url.PathEscape(part))
|
|
}
|
|
return strings.Join(encoded, "/"), nil
|
|
}
|
|
|
|
// decodeBase64Content decodes base64-encoded content from the GitHub contents API.
|
|
// GitHub returns base64 content with line breaks for formatting; we strip \r and \n before decoding.
|
|
func decodeBase64Content(encoded string) (string, error) {
|
|
cleaned := strings.NewReplacer("\n", "", "\r", "").Replace(encoded)
|
|
decoded, err := base64.StdEncoding.DecodeString(cleaned)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
return string(decoded), nil
|
|
}
|