| 1 | // Copyright 2012 The Go Authors. All rights reserved. |
|---|---|
| 2 | // Use of this source code is governed by a BSD-style |
| 3 | // license that can be found in the LICENSE file. |
| 4 | |
| 5 | // Package vcs exposes functions for resolving import paths |
| 6 | // and using version control systems, which can be used to |
| 7 | // implement behavior similar to the standard "go get" command. |
| 8 | // |
| 9 | // This package is a copy of internal code in package cmd/go/internal/get, |
| 10 | // modified to make the identifiers exported. It's provided here |
| 11 | // for developers who want to write tools with similar semantics. |
| 12 | // It needs to be manually kept in sync with upstream when changes are |
| 13 | // made to cmd/go/internal/get; see https://golang.org/issue/11490. |
| 14 | package vcs // import "golang.org/x/tools/go/vcs" |
| 15 | |
| 16 | import ( |
| 17 | "bytes" |
| 18 | "encoding/json" |
| 19 | "errors" |
| 20 | "fmt" |
| 21 | exec "golang.org/x/sys/execabs" |
| 22 | "log" |
| 23 | "net/url" |
| 24 | "os" |
| 25 | "path/filepath" |
| 26 | "regexp" |
| 27 | "strconv" |
| 28 | "strings" |
| 29 | ) |
| 30 | |
| 31 | // Verbose enables verbose operation logging. |
| 32 | var Verbose bool |
| 33 | |
| 34 | // ShowCmd controls whether VCS commands are printed. |
| 35 | var ShowCmd bool |
| 36 | |
| 37 | // A Cmd describes how to use a version control system |
| 38 | // like Mercurial, Git, or Subversion. |
| 39 | type Cmd struct { |
| 40 | Name string |
| 41 | Cmd string // name of binary to invoke command |
| 42 | |
| 43 | CreateCmd string // command to download a fresh copy of a repository |
| 44 | DownloadCmd string // command to download updates into an existing repository |
| 45 | |
| 46 | TagCmd []TagCmd // commands to list tags |
| 47 | TagLookupCmd []TagCmd // commands to lookup tags before running tagSyncCmd |
| 48 | TagSyncCmd string // command to sync to specific tag |
| 49 | TagSyncDefault string // command to sync to default tag |
| 50 | |
| 51 | LogCmd string // command to list repository changelogs in an XML format |
| 52 | |
| 53 | Scheme []string |
| 54 | PingCmd string |
| 55 | } |
| 56 | |
| 57 | // A TagCmd describes a command to list available tags |
| 58 | // that can be passed to Cmd.TagSyncCmd. |
| 59 | type TagCmd struct { |
| 60 | Cmd string // command to list tags |
| 61 | Pattern string // regexp to extract tags from list |
| 62 | } |
| 63 | |
| 64 | // vcsList lists the known version control systems |
| 65 | var vcsList = []*Cmd{ |
| 66 | vcsHg, |
| 67 | vcsGit, |
| 68 | vcsSvn, |
| 69 | vcsBzr, |
| 70 | } |
| 71 | |
| 72 | // ByCmd returns the version control system for the given |
| 73 | // command name (hg, git, svn, bzr). |
| 74 | func ByCmd(cmd string) *Cmd { |
| 75 | for _, vcs := range vcsList { |
| 76 | if vcs.Cmd == cmd { |
| 77 | return vcs |
| 78 | } |
| 79 | } |
| 80 | return nil |
| 81 | } |
| 82 | |
| 83 | // vcsHg describes how to use Mercurial. |
| 84 | var vcsHg = &Cmd{ |
| 85 | Name: "Mercurial", |
| 86 | Cmd: "hg", |
| 87 | |
| 88 | CreateCmd: "clone -U {repo} {dir}", |
| 89 | DownloadCmd: "pull", |
| 90 | |
| 91 | // We allow both tag and branch names as 'tags' |
| 92 | // for selecting a version. This lets people have |
| 93 | // a go.release.r60 branch and a go1 branch |
| 94 | // and make changes in both, without constantly |
| 95 | // editing .hgtags. |
| 96 | TagCmd: []TagCmd{ |
| 97 | {"tags", `^(\S+)`}, |
| 98 | {"branches", `^(\S+)`}, |
| 99 | }, |
| 100 | TagSyncCmd: "update -r {tag}", |
| 101 | TagSyncDefault: "update default", |
| 102 | |
| 103 | LogCmd: "log --encoding=utf-8 --limit={limit} --template={template}", |
| 104 | |
| 105 | Scheme: []string{"https", "http", "ssh"}, |
| 106 | PingCmd: "identify {scheme}://{repo}", |
| 107 | } |
| 108 | |
| 109 | // vcsGit describes how to use Git. |
| 110 | var vcsGit = &Cmd{ |
| 111 | Name: "Git", |
| 112 | Cmd: "git", |
| 113 | |
| 114 | CreateCmd: "clone {repo} {dir}", |
| 115 | DownloadCmd: "pull --ff-only", |
| 116 | |
| 117 | TagCmd: []TagCmd{ |
| 118 | // tags/xxx matches a git tag named xxx |
| 119 | // origin/xxx matches a git branch named xxx on the default remote repository |
| 120 | {"show-ref", `(?:tags|origin)/(\S+)$`}, |
| 121 | }, |
| 122 | TagLookupCmd: []TagCmd{ |
| 123 | {"show-ref tags/{tag} origin/{tag}", `((?:tags|origin)/\S+)$`}, |
| 124 | }, |
| 125 | TagSyncCmd: "checkout {tag}", |
| 126 | TagSyncDefault: "checkout master", |
| 127 | |
| 128 | Scheme: []string{"git", "https", "http", "git+ssh"}, |
| 129 | PingCmd: "ls-remote {scheme}://{repo}", |
| 130 | } |
| 131 | |
| 132 | // vcsBzr describes how to use Bazaar. |
| 133 | var vcsBzr = &Cmd{ |
| 134 | Name: "Bazaar", |
| 135 | Cmd: "bzr", |
| 136 | |
| 137 | CreateCmd: "branch {repo} {dir}", |
| 138 | |
| 139 | // Without --overwrite bzr will not pull tags that changed. |
| 140 | // Replace by --overwrite-tags after http://pad.lv/681792 goes in. |
| 141 | DownloadCmd: "pull --overwrite", |
| 142 | |
| 143 | TagCmd: []TagCmd{{"tags", `^(\S+)`}}, |
| 144 | TagSyncCmd: "update -r {tag}", |
| 145 | TagSyncDefault: "update -r revno:-1", |
| 146 | |
| 147 | Scheme: []string{"https", "http", "bzr", "bzr+ssh"}, |
| 148 | PingCmd: "info {scheme}://{repo}", |
| 149 | } |
| 150 | |
| 151 | // vcsSvn describes how to use Subversion. |
| 152 | var vcsSvn = &Cmd{ |
| 153 | Name: "Subversion", |
| 154 | Cmd: "svn", |
| 155 | |
| 156 | CreateCmd: "checkout {repo} {dir}", |
| 157 | DownloadCmd: "update", |
| 158 | |
| 159 | // There is no tag command in subversion. |
| 160 | // The branch information is all in the path names. |
| 161 | |
| 162 | LogCmd: "log --xml --limit={limit}", |
| 163 | |
| 164 | Scheme: []string{"https", "http", "svn", "svn+ssh"}, |
| 165 | PingCmd: "info {scheme}://{repo}", |
| 166 | } |
| 167 | |
| 168 | func (v *Cmd) String() string { |
| 169 | return v.Name |
| 170 | } |
| 171 | |
| 172 | // run runs the command line cmd in the given directory. |
| 173 | // keyval is a list of key, value pairs. run expands |
| 174 | // instances of {key} in cmd into value, but only after |
| 175 | // splitting cmd into individual arguments. |
| 176 | // If an error occurs, run prints the command line and the |
| 177 | // command's combined stdout+stderr to standard error. |
| 178 | // Otherwise run discards the command's output. |
| 179 | func (v *Cmd) run(dir string, cmd string, keyval ...string) error { |
| 180 | _, err := v.run1(dir, cmd, keyval, true) |
| 181 | return err |
| 182 | } |
| 183 | |
| 184 | // runVerboseOnly is like run but only generates error output to standard error in verbose mode. |
| 185 | func (v *Cmd) runVerboseOnly(dir string, cmd string, keyval ...string) error { |
| 186 | _, err := v.run1(dir, cmd, keyval, false) |
| 187 | return err |
| 188 | } |
| 189 | |
| 190 | // runOutput is like run but returns the output of the command. |
| 191 | func (v *Cmd) runOutput(dir string, cmd string, keyval ...string) ([]byte, error) { |
| 192 | return v.run1(dir, cmd, keyval, true) |
| 193 | } |
| 194 | |
| 195 | // run1 is the generalized implementation of run and runOutput. |
| 196 | func (v *Cmd) run1(dir string, cmdline string, keyval []string, verbose bool) ([]byte, error) { |
| 197 | m := make(map[string]string) |
| 198 | for i := 0; i < len(keyval); i += 2 { |
| 199 | m[keyval[i]] = keyval[i+1] |
| 200 | } |
| 201 | args := strings.Fields(cmdline) |
| 202 | for i, arg := range args { |
| 203 | args[i] = expand(m, arg) |
| 204 | } |
| 205 | |
| 206 | _, err := exec.LookPath(v.Cmd) |
| 207 | if err != nil { |
| 208 | fmt.Fprintf(os.Stderr, |
| 209 | "go: missing %s command. See http://golang.org/s/gogetcmd\n", |
| 210 | v.Name) |
| 211 | return nil, err |
| 212 | } |
| 213 | |
| 214 | cmd := exec.Command(v.Cmd, args...) |
| 215 | cmd.Dir = dir |
| 216 | cmd.Env = envForDir(cmd.Dir) |
| 217 | if ShowCmd { |
| 218 | fmt.Printf("cd %s\n", dir) |
| 219 | fmt.Printf("%s %s\n", v.Cmd, strings.Join(args, " ")) |
| 220 | } |
| 221 | var buf bytes.Buffer |
| 222 | cmd.Stdout = &buf |
| 223 | cmd.Stderr = &buf |
| 224 | err = cmd.Run() |
| 225 | out := buf.Bytes() |
| 226 | if err != nil { |
| 227 | if verbose || Verbose { |
| 228 | fmt.Fprintf(os.Stderr, "# cd %s; %s %s\n", dir, v.Cmd, strings.Join(args, " ")) |
| 229 | os.Stderr.Write(out) |
| 230 | } |
| 231 | return nil, err |
| 232 | } |
| 233 | return out, nil |
| 234 | } |
| 235 | |
| 236 | // Ping pings the repo to determine if scheme used is valid. |
| 237 | // This repo must be pingable with this scheme and VCS. |
| 238 | func (v *Cmd) Ping(scheme, repo string) error { |
| 239 | return v.runVerboseOnly(".", v.PingCmd, "scheme", scheme, "repo", repo) |
| 240 | } |
| 241 | |
| 242 | // Create creates a new copy of repo in dir. |
| 243 | // The parent of dir must exist; dir must not. |
| 244 | func (v *Cmd) Create(dir, repo string) error { |
| 245 | return v.run(".", v.CreateCmd, "dir", dir, "repo", repo) |
| 246 | } |
| 247 | |
| 248 | // CreateAtRev creates a new copy of repo in dir at revision rev. |
| 249 | // The parent of dir must exist; dir must not. |
| 250 | // rev must be a valid revision in repo. |
| 251 | func (v *Cmd) CreateAtRev(dir, repo, rev string) error { |
| 252 | if err := v.Create(dir, repo); err != nil { |
| 253 | return err |
| 254 | } |
| 255 | return v.run(dir, v.TagSyncCmd, "tag", rev) |
| 256 | } |
| 257 | |
| 258 | // Download downloads any new changes for the repo in dir. |
| 259 | // dir must be a valid VCS repo compatible with v. |
| 260 | func (v *Cmd) Download(dir string) error { |
| 261 | return v.run(dir, v.DownloadCmd) |
| 262 | } |
| 263 | |
| 264 | // Tags returns the list of available tags for the repo in dir. |
| 265 | // dir must be a valid VCS repo compatible with v. |
| 266 | func (v *Cmd) Tags(dir string) ([]string, error) { |
| 267 | var tags []string |
| 268 | for _, tc := range v.TagCmd { |
| 269 | out, err := v.runOutput(dir, tc.Cmd) |
| 270 | if err != nil { |
| 271 | return nil, err |
| 272 | } |
| 273 | re := regexp.MustCompile(`(?m-s)` + tc.Pattern) |
| 274 | for _, m := range re.FindAllStringSubmatch(string(out), -1) { |
| 275 | tags = append(tags, m[1]) |
| 276 | } |
| 277 | } |
| 278 | return tags, nil |
| 279 | } |
| 280 | |
| 281 | // TagSync syncs the repo in dir to the named tag, which is either a |
| 282 | // tag returned by Tags or the empty string (the default tag). |
| 283 | // dir must be a valid VCS repo compatible with v and the tag must exist. |
| 284 | func (v *Cmd) TagSync(dir, tag string) error { |
| 285 | if v.TagSyncCmd == "" { |
| 286 | return nil |
| 287 | } |
| 288 | if tag != "" { |
| 289 | for _, tc := range v.TagLookupCmd { |
| 290 | out, err := v.runOutput(dir, tc.Cmd, "tag", tag) |
| 291 | if err != nil { |
| 292 | return err |
| 293 | } |
| 294 | re := regexp.MustCompile(`(?m-s)` + tc.Pattern) |
| 295 | m := re.FindStringSubmatch(string(out)) |
| 296 | if len(m) > 1 { |
| 297 | tag = m[1] |
| 298 | break |
| 299 | } |
| 300 | } |
| 301 | } |
| 302 | if tag == "" && v.TagSyncDefault != "" { |
| 303 | return v.run(dir, v.TagSyncDefault) |
| 304 | } |
| 305 | return v.run(dir, v.TagSyncCmd, "tag", tag) |
| 306 | } |
| 307 | |
| 308 | // Log logs the changes for the repo in dir. |
| 309 | // dir must be a valid VCS repo compatible with v. |
| 310 | func (v *Cmd) Log(dir, logTemplate string) ([]byte, error) { |
| 311 | if err := v.Download(dir); err != nil { |
| 312 | return []byte{}, err |
| 313 | } |
| 314 | |
| 315 | const N = 50 // how many revisions to grab |
| 316 | return v.runOutput(dir, v.LogCmd, "limit", strconv.Itoa(N), "template", logTemplate) |
| 317 | } |
| 318 | |
| 319 | // LogAtRev logs the change for repo in dir at the rev revision. |
| 320 | // dir must be a valid VCS repo compatible with v. |
| 321 | // rev must be a valid revision for the repo in dir. |
| 322 | func (v *Cmd) LogAtRev(dir, rev, logTemplate string) ([]byte, error) { |
| 323 | if err := v.Download(dir); err != nil { |
| 324 | return []byte{}, err |
| 325 | } |
| 326 | |
| 327 | // Append revision flag to LogCmd. |
| 328 | logAtRevCmd := v.LogCmd + " --rev=" + rev |
| 329 | return v.runOutput(dir, logAtRevCmd, "limit", strconv.Itoa(1), "template", logTemplate) |
| 330 | } |
| 331 | |
| 332 | // A vcsPath describes how to convert an import path into a |
| 333 | // version control system and repository name. |
| 334 | type vcsPath struct { |
| 335 | prefix string // prefix this description applies to |
| 336 | re string // pattern for import path |
| 337 | repo string // repository to use (expand with match of re) |
| 338 | vcs string // version control system to use (expand with match of re) |
| 339 | check func(match map[string]string) error // additional checks |
| 340 | ping bool // ping for scheme to use to download repo |
| 341 | |
| 342 | regexp *regexp.Regexp // cached compiled form of re |
| 343 | } |
| 344 | |
| 345 | // FromDir inspects dir and its parents to determine the |
| 346 | // version control system and code repository to use. |
| 347 | // On return, root is the import path |
| 348 | // corresponding to the root of the repository. |
| 349 | func FromDir(dir, srcRoot string) (vcs *Cmd, root string, err error) { |
| 350 | // Clean and double-check that dir is in (a subdirectory of) srcRoot. |
| 351 | dir = filepath.Clean(dir) |
| 352 | srcRoot = filepath.Clean(srcRoot) |
| 353 | if len(dir) <= len(srcRoot) || dir[len(srcRoot)] != filepath.Separator { |
| 354 | return nil, "", fmt.Errorf("directory %q is outside source root %q", dir, srcRoot) |
| 355 | } |
| 356 | |
| 357 | var vcsRet *Cmd |
| 358 | var rootRet string |
| 359 | |
| 360 | origDir := dir |
| 361 | for len(dir) > len(srcRoot) { |
| 362 | for _, vcs := range vcsList { |
| 363 | if _, err := os.Stat(filepath.Join(dir, "."+vcs.Cmd)); err == nil { |
| 364 | root := filepath.ToSlash(dir[len(srcRoot)+1:]) |
| 365 | // Record first VCS we find, but keep looking, |
| 366 | // to detect mistakes like one kind of VCS inside another. |
| 367 | if vcsRet == nil { |
| 368 | vcsRet = vcs |
| 369 | rootRet = root |
| 370 | continue |
| 371 | } |
| 372 | // Allow .git inside .git, which can arise due to submodules. |
| 373 | if vcsRet == vcs && vcs.Cmd == "git" { |
| 374 | continue |
| 375 | } |
| 376 | // Otherwise, we have one VCS inside a different VCS. |
| 377 | return nil, "", fmt.Errorf("directory %q uses %s, but parent %q uses %s", |
| 378 | filepath.Join(srcRoot, rootRet), vcsRet.Cmd, filepath.Join(srcRoot, root), vcs.Cmd) |
| 379 | } |
| 380 | } |
| 381 | |
| 382 | // Move to parent. |
| 383 | ndir := filepath.Dir(dir) |
| 384 | if len(ndir) >= len(dir) { |
| 385 | // Shouldn't happen, but just in case, stop. |
| 386 | break |
| 387 | } |
| 388 | dir = ndir |
| 389 | } |
| 390 | |
| 391 | if vcsRet != nil { |
| 392 | return vcsRet, rootRet, nil |
| 393 | } |
| 394 | |
| 395 | return nil, "", fmt.Errorf("directory %q is not using a known version control system", origDir) |
| 396 | } |
| 397 | |
| 398 | // RepoRoot represents a version control system, a repo, and a root of |
| 399 | // where to put it on disk. |
| 400 | type RepoRoot struct { |
| 401 | VCS *Cmd |
| 402 | |
| 403 | // Repo is the repository URL, including scheme. |
| 404 | Repo string |
| 405 | |
| 406 | // Root is the import path corresponding to the root of the |
| 407 | // repository. |
| 408 | Root string |
| 409 | } |
| 410 | |
| 411 | // RepoRootForImportPath analyzes importPath to determine the |
| 412 | // version control system, and code repository to use. |
| 413 | func RepoRootForImportPath(importPath string, verbose bool) (*RepoRoot, error) { |
| 414 | rr, err := RepoRootForImportPathStatic(importPath, "") |
| 415 | if err == errUnknownSite { |
| 416 | rr, err = RepoRootForImportDynamic(importPath, verbose) |
| 417 | |
| 418 | // RepoRootForImportDynamic returns error detail |
| 419 | // that is irrelevant if the user didn't intend to use a |
| 420 | // dynamic import in the first place. |
| 421 | // Squelch it. |
| 422 | if err != nil { |
| 423 | if Verbose { |
| 424 | log.Printf("import %q: %v", importPath, err) |
| 425 | } |
| 426 | err = fmt.Errorf("unrecognized import path %q", importPath) |
| 427 | } |
| 428 | } |
| 429 | |
| 430 | if err == nil && strings.Contains(importPath, "...") && strings.Contains(rr.Root, "...") { |
| 431 | // Do not allow wildcards in the repo root. |
| 432 | rr = nil |
| 433 | err = fmt.Errorf("cannot expand ... in %q", importPath) |
| 434 | } |
| 435 | return rr, err |
| 436 | } |
| 437 | |
| 438 | var errUnknownSite = errors.New("dynamic lookup required to find mapping") |
| 439 | |
| 440 | // RepoRootForImportPathStatic attempts to map importPath to a |
| 441 | // RepoRoot using the commonly-used VCS hosting sites in vcsPaths |
| 442 | // (github.com/user/dir), or from a fully-qualified importPath already |
| 443 | // containing its VCS type (foo.com/repo.git/dir) |
| 444 | // |
| 445 | // If scheme is non-empty, that scheme is forced. |
| 446 | func RepoRootForImportPathStatic(importPath, scheme string) (*RepoRoot, error) { |
| 447 | if strings.Contains(importPath, "://") { |
| 448 | return nil, fmt.Errorf("invalid import path %q", importPath) |
| 449 | } |
| 450 | for _, srv := range vcsPaths { |
| 451 | if !strings.HasPrefix(importPath, srv.prefix) { |
| 452 | continue |
| 453 | } |
| 454 | m := srv.regexp.FindStringSubmatch(importPath) |
| 455 | if m == nil { |
| 456 | if srv.prefix != "" { |
| 457 | return nil, fmt.Errorf("invalid %s import path %q", srv.prefix, importPath) |
| 458 | } |
| 459 | continue |
| 460 | } |
| 461 | |
| 462 | // Build map of named subexpression matches for expand. |
| 463 | match := map[string]string{ |
| 464 | "prefix": srv.prefix, |
| 465 | "import": importPath, |
| 466 | } |
| 467 | for i, name := range srv.regexp.SubexpNames() { |
| 468 | if name != "" && match[name] == "" { |
| 469 | match[name] = m[i] |
| 470 | } |
| 471 | } |
| 472 | if srv.vcs != "" { |
| 473 | match["vcs"] = expand(match, srv.vcs) |
| 474 | } |
| 475 | if srv.repo != "" { |
| 476 | match["repo"] = expand(match, srv.repo) |
| 477 | } |
| 478 | if srv.check != nil { |
| 479 | if err := srv.check(match); err != nil { |
| 480 | return nil, err |
| 481 | } |
| 482 | } |
| 483 | vcs := ByCmd(match["vcs"]) |
| 484 | if vcs == nil { |
| 485 | return nil, fmt.Errorf("unknown version control system %q", match["vcs"]) |
| 486 | } |
| 487 | if srv.ping { |
| 488 | if scheme != "" { |
| 489 | match["repo"] = scheme + "://" + match["repo"] |
| 490 | } else { |
| 491 | for _, scheme := range vcs.Scheme { |
| 492 | if vcs.Ping(scheme, match["repo"]) == nil { |
| 493 | match["repo"] = scheme + "://" + match["repo"] |
| 494 | break |
| 495 | } |
| 496 | } |
| 497 | } |
| 498 | } |
| 499 | rr := &RepoRoot{ |
| 500 | VCS: vcs, |
| 501 | Repo: match["repo"], |
| 502 | Root: match["root"], |
| 503 | } |
| 504 | return rr, nil |
| 505 | } |
| 506 | return nil, errUnknownSite |
| 507 | } |
| 508 | |
| 509 | // RepoRootForImportDynamic finds a *RepoRoot for a custom domain that's not |
| 510 | // statically known by RepoRootForImportPathStatic. |
| 511 | // |
| 512 | // This handles custom import paths like "name.tld/pkg/foo" or just "name.tld". |
| 513 | func RepoRootForImportDynamic(importPath string, verbose bool) (*RepoRoot, error) { |
| 514 | slash := strings.Index(importPath, "/") |
| 515 | if slash < 0 { |
| 516 | slash = len(importPath) |
| 517 | } |
| 518 | host := importPath[:slash] |
| 519 | if !strings.Contains(host, ".") { |
| 520 | return nil, errors.New("import path doesn't contain a hostname") |
| 521 | } |
| 522 | urlStr, body, err := httpsOrHTTP(importPath) |
| 523 | if err != nil { |
| 524 | return nil, fmt.Errorf("http/https fetch: %v", err) |
| 525 | } |
| 526 | defer body.Close() |
| 527 | imports, err := parseMetaGoImports(body) |
| 528 | if err != nil { |
| 529 | return nil, fmt.Errorf("parsing %s: %v", importPath, err) |
| 530 | } |
| 531 | metaImport, err := matchGoImport(imports, importPath) |
| 532 | if err != nil { |
| 533 | if err != errNoMatch { |
| 534 | return nil, fmt.Errorf("parse %s: %v", urlStr, err) |
| 535 | } |
| 536 | return nil, fmt.Errorf("parse %s: no go-import meta tags", urlStr) |
| 537 | } |
| 538 | if verbose { |
| 539 | log.Printf("get %q: found meta tag %#v at %s", importPath, metaImport, urlStr) |
| 540 | } |
| 541 | // If the import was "uni.edu/bob/project", which said the |
| 542 | // prefix was "uni.edu" and the RepoRoot was "evilroot.com", |
| 543 | // make sure we don't trust Bob and check out evilroot.com to |
| 544 | // "uni.edu" yet (possibly overwriting/preempting another |
| 545 | // non-evil student). Instead, first verify the root and see |
| 546 | // if it matches Bob's claim. |
| 547 | if metaImport.Prefix != importPath { |
| 548 | if verbose { |
| 549 | log.Printf("get %q: verifying non-authoritative meta tag", importPath) |
| 550 | } |
| 551 | urlStr0 := urlStr |
| 552 | urlStr, body, err = httpsOrHTTP(metaImport.Prefix) |
| 553 | if err != nil { |
| 554 | return nil, fmt.Errorf("fetch %s: %v", urlStr, err) |
| 555 | } |
| 556 | imports, err := parseMetaGoImports(body) |
| 557 | if err != nil { |
| 558 | return nil, fmt.Errorf("parsing %s: %v", importPath, err) |
| 559 | } |
| 560 | if len(imports) == 0 { |
| 561 | return nil, fmt.Errorf("fetch %s: no go-import meta tag", urlStr) |
| 562 | } |
| 563 | metaImport2, err := matchGoImport(imports, importPath) |
| 564 | if err != nil || metaImport != metaImport2 { |
| 565 | return nil, fmt.Errorf("%s and %s disagree about go-import for %s", urlStr0, urlStr, metaImport.Prefix) |
| 566 | } |
| 567 | } |
| 568 | |
| 569 | if err := validateRepoRoot(metaImport.RepoRoot); err != nil { |
| 570 | return nil, fmt.Errorf("%s: invalid repo root %q: %v", urlStr, metaImport.RepoRoot, err) |
| 571 | } |
| 572 | rr := &RepoRoot{ |
| 573 | VCS: ByCmd(metaImport.VCS), |
| 574 | Repo: metaImport.RepoRoot, |
| 575 | Root: metaImport.Prefix, |
| 576 | } |
| 577 | if rr.VCS == nil { |
| 578 | return nil, fmt.Errorf("%s: unknown vcs %q", urlStr, metaImport.VCS) |
| 579 | } |
| 580 | return rr, nil |
| 581 | } |
| 582 | |
| 583 | // validateRepoRoot returns an error if repoRoot does not seem to be |
| 584 | // a valid URL with scheme. |
| 585 | func validateRepoRoot(repoRoot string) error { |
| 586 | url, err := url.Parse(repoRoot) |
| 587 | if err != nil { |
| 588 | return err |
| 589 | } |
| 590 | if url.Scheme == "" { |
| 591 | return errors.New("no scheme") |
| 592 | } |
| 593 | return nil |
| 594 | } |
| 595 | |
| 596 | // metaImport represents the parsed <meta name="go-import" |
| 597 | // content="prefix vcs reporoot" /> tags from HTML files. |
| 598 | type metaImport struct { |
| 599 | Prefix, VCS, RepoRoot string |
| 600 | } |
| 601 | |
| 602 | // errNoMatch is returned from matchGoImport when there's no applicable match. |
| 603 | var errNoMatch = errors.New("no import match") |
| 604 | |
| 605 | // pathPrefix reports whether sub is a prefix of s, |
| 606 | // only considering entire path components. |
| 607 | func pathPrefix(s, sub string) bool { |
| 608 | // strings.HasPrefix is necessary but not sufficient. |
| 609 | if !strings.HasPrefix(s, sub) { |
| 610 | return false |
| 611 | } |
| 612 | // The remainder after the prefix must either be empty or start with a slash. |
| 613 | rem := s[len(sub):] |
| 614 | return rem == "" || rem[0] == '/' |
| 615 | } |
| 616 | |
| 617 | // matchGoImport returns the metaImport from imports matching importPath. |
| 618 | // An error is returned if there are multiple matches. |
| 619 | // errNoMatch is returned if none match. |
| 620 | func matchGoImport(imports []metaImport, importPath string) (_ metaImport, err error) { |
| 621 | match := -1 |
| 622 | for i, im := range imports { |
| 623 | if !pathPrefix(importPath, im.Prefix) { |
| 624 | continue |
| 625 | } |
| 626 | |
| 627 | if match != -1 { |
| 628 | err = fmt.Errorf("multiple meta tags match import path %q", importPath) |
| 629 | return |
| 630 | } |
| 631 | match = i |
| 632 | } |
| 633 | if match == -1 { |
| 634 | err = errNoMatch |
| 635 | return |
| 636 | } |
| 637 | return imports[match], nil |
| 638 | } |
| 639 | |
| 640 | // expand rewrites s to replace {k} with match[k] for each key k in match. |
| 641 | func expand(match map[string]string, s string) string { |
| 642 | for k, v := range match { |
| 643 | s = strings.Replace(s, "{"+k+"}", v, -1) |
| 644 | } |
| 645 | return s |
| 646 | } |
| 647 | |
| 648 | // vcsPaths lists the known vcs paths. |
| 649 | var vcsPaths = []*vcsPath{ |
| 650 | // Github |
| 651 | { |
| 652 | prefix: "github.com/", |
| 653 | re: `^(?P<root>github\.com/[A-Za-z0-9_.\-]+/[A-Za-z0-9_.\-]+)(/[\p{L}0-9_.\-]+)*$`, |
| 654 | vcs: "git", |
| 655 | repo: "https://{root}", |
| 656 | check: noVCSSuffix, |
| 657 | }, |
| 658 | |
| 659 | // Bitbucket |
| 660 | { |
| 661 | prefix: "bitbucket.org/", |
| 662 | re: `^(?P<root>bitbucket\.org/(?P<bitname>[A-Za-z0-9_.\-]+/[A-Za-z0-9_.\-]+))(/[A-Za-z0-9_.\-]+)*$`, |
| 663 | repo: "https://{root}", |
| 664 | check: bitbucketVCS, |
| 665 | }, |
| 666 | |
| 667 | // Launchpad |
| 668 | { |
| 669 | prefix: "launchpad.net/", |
| 670 | re: `^(?P<root>launchpad\.net/((?P<project>[A-Za-z0-9_.\-]+)(?P<series>/[A-Za-z0-9_.\-]+)?|~[A-Za-z0-9_.\-]+/(\+junk|[A-Za-z0-9_.\-]+)/[A-Za-z0-9_.\-]+))(/[A-Za-z0-9_.\-]+)*$`, |
| 671 | vcs: "bzr", |
| 672 | repo: "https://{root}", |
| 673 | check: launchpadVCS, |
| 674 | }, |
| 675 | |
| 676 | // Git at OpenStack |
| 677 | { |
| 678 | prefix: "git.openstack.org", |
| 679 | re: `^(?P<root>git\.openstack\.org/[A-Za-z0-9_.\-]+/[A-Za-z0-9_.\-]+)(\.git)?(/[A-Za-z0-9_.\-]+)*$`, |
| 680 | vcs: "git", |
| 681 | repo: "https://{root}", |
| 682 | check: noVCSSuffix, |
| 683 | }, |
| 684 | |
| 685 | // General syntax for any server. |
| 686 | { |
| 687 | re: `^(?P<root>(?P<repo>([a-z0-9.\-]+\.)+[a-z0-9.\-]+(:[0-9]+)?/[A-Za-z0-9_.\-/]*?)\.(?P<vcs>bzr|git|hg|svn))(/[A-Za-z0-9_.\-]+)*$`, |
| 688 | ping: true, |
| 689 | }, |
| 690 | } |
| 691 | |
| 692 | func init() { |
| 693 | // fill in cached regexps. |
| 694 | // Doing this eagerly discovers invalid regexp syntax |
| 695 | // without having to run a command that needs that regexp. |
| 696 | for _, srv := range vcsPaths { |
| 697 | srv.regexp = regexp.MustCompile(srv.re) |
| 698 | } |
| 699 | } |
| 700 | |
| 701 | // noVCSSuffix checks that the repository name does not |
| 702 | // end in .foo for any version control system foo. |
| 703 | // The usual culprit is ".git". |
| 704 | func noVCSSuffix(match map[string]string) error { |
| 705 | repo := match["repo"] |
| 706 | for _, vcs := range vcsList { |
| 707 | if strings.HasSuffix(repo, "."+vcs.Cmd) { |
| 708 | return fmt.Errorf("invalid version control suffix in %s path", match["prefix"]) |
| 709 | } |
| 710 | } |
| 711 | return nil |
| 712 | } |
| 713 | |
| 714 | // bitbucketVCS determines the version control system for a |
| 715 | // Bitbucket repository, by using the Bitbucket API. |
| 716 | func bitbucketVCS(match map[string]string) error { |
| 717 | if err := noVCSSuffix(match); err != nil { |
| 718 | return err |
| 719 | } |
| 720 | |
| 721 | var resp struct { |
| 722 | SCM string `json:"scm"` |
| 723 | } |
| 724 | url := expand(match, "https://api.bitbucket.org/2.0/repositories/{bitname}?fields=scm") |
| 725 | data, err := httpGET(url) |
| 726 | if err != nil { |
| 727 | return err |
| 728 | } |
| 729 | if err := json.Unmarshal(data, &resp); err != nil { |
| 730 | return fmt.Errorf("decoding %s: %v", url, err) |
| 731 | } |
| 732 | |
| 733 | if ByCmd(resp.SCM) != nil { |
| 734 | match["vcs"] = resp.SCM |
| 735 | if resp.SCM == "git" { |
| 736 | match["repo"] += ".git" |
| 737 | } |
| 738 | return nil |
| 739 | } |
| 740 | |
| 741 | return fmt.Errorf("unable to detect version control system for bitbucket.org/ path") |
| 742 | } |
| 743 | |
| 744 | // launchpadVCS solves the ambiguity for "lp.net/project/foo". In this case, |
| 745 | // "foo" could be a series name registered in Launchpad with its own branch, |
| 746 | // and it could also be the name of a directory within the main project |
| 747 | // branch one level up. |
| 748 | func launchpadVCS(match map[string]string) error { |
| 749 | if match["project"] == "" || match["series"] == "" { |
| 750 | return nil |
| 751 | } |
| 752 | _, err := httpGET(expand(match, "https://code.launchpad.net/{project}{series}/.bzr/branch-format")) |
| 753 | if err != nil { |
| 754 | match["root"] = expand(match, "launchpad.net/{project}") |
| 755 | match["repo"] = expand(match, "https://{root}") |
| 756 | } |
| 757 | return nil |
| 758 | } |
| 759 |
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