15954: Avoid modifying caller's global environment.

Arvados-DCO-1.1-Signed-off-by: Tom Clegg <tom@tomclegg.ca>

diff --git a/lib/boot/cmd.go b/lib/boot/cmd.go
index cfa6b425811aa2bac5a3864e11eac37e728df0e3..d0a566d6b29281818de17d17e3417cd9df9875be 100644 (file)
--- a/lib/boot/cmd.go
+++ b/lib/boot/cmd.go
@@ -44,7 +44,9 @@ type bootCommand struct {
        stdout  io.Writer
        stderr  io.Writer
 
-       tempdir string
+       tempdir    string
+       configfile string
+       environ    []string // for child processes
 
        setupRubyOnce sync.Once
        setupRubyErr  error
@@ -127,9 +129,12 @@ func (boot *bootCommand) RunCommand(prog string, args []string, stdin io.Reader,
        if err != nil {
                return 1
        }
-       os.Setenv("ARVADOS_CONFIG", conffile.Name())
-       arvados.DefaultConfigFile = conffile.Name()
-       os.Setenv("RAILS_ENV", boot.clusterType)
+       boot.configfile = conffile.Name()
+
+       boot.environ = os.Environ()
+       boot.setEnv("ARVADOS_CONFIG", boot.configfile)
+       boot.setEnv("RAILS_ENV", boot.clusterType)
+       boot.prependEnv("PATH", filepath.Join(boot.libPath, "bin")+":")
 
        // Now that we have the config, replace the bootstrap logger
        // with a new one according to the logging config.
@@ -146,7 +151,7 @@ func (boot *bootCommand) RunCommand(prog string, args []string, stdin io.Reader,
        defer cancel()
 
        ch := make(chan os.Signal)
-       signal.Notify(ch, syscall.SIGINT)
+       signal.Notify(ch, syscall.SIGINT, syscall.SIGTERM)
        go func() {
                for sig := range ch {
                        logger.WithField("signal", sig).Info("caught signal")
@@ -164,12 +169,14 @@ func (boot *bootCommand) RunCommand(prog string, args []string, stdin io.Reader,
                        return 1
                }
        }
-       os.Setenv("PATH", filepath.Join(boot.libPath, "bin")+":"+os.Getenv("PATH"))
-
        err = boot.installGoProgram(ctx, "cmd/arvados-server")
        if err != nil {
                return 1
        }
+       err = boot.setupRubyEnv()
+       if err != nil {
+               return 1
+       }
 
        var wg sync.WaitGroup
        for _, cmpt := range []component{
@@ -228,6 +235,26 @@ func (boot *bootCommand) waitUntilReady(ctx context.Context) bool {
        return true
 }
 
+func (boot *bootCommand) prependEnv(key, prepend string) {
+       for i, s := range boot.environ {
+               if strings.HasPrefix(s, key+"=") {
+                       boot.environ[i] = key + "=" + prepend + s[len(key)+1:]
+                       return
+               }
+       }
+       boot.environ = append(boot.environ, key+"="+prepend)
+}
+
+func (boot *bootCommand) setEnv(key, val string) {
+       for i, s := range boot.environ {
+               if strings.HasPrefix(s, key+"=") {
+                       boot.environ[i] = key + "=" + val
+                       return
+               }
+       }
+       boot.environ = append(boot.environ, key+"="+val)
+}
+
 func (boot *bootCommand) installGoProgram(ctx context.Context, srcpath string) error {
        boot.goMutex.Lock()
        defer boot.goMutex.Unlock()
@@ -235,17 +262,29 @@ func (boot *bootCommand) installGoProgram(ctx context.Context, srcpath string) e
 }
 
 func (boot *bootCommand) setupRubyEnv() error {
-       boot.setupRubyOnce.Do(func() {
-               buf, err := exec.Command("gem", "env", "gempath").Output() // /var/lib/arvados/.gem/ruby/2.5.0/bin:...
-               if err != nil || len(buf) == 0 {
-                       boot.setupRubyErr = fmt.Errorf("gem env gempath: %v", err)
+       buf, err := exec.Command("gem", "env", "gempath").Output() // /var/lib/arvados/.gem/ruby/2.5.0/bin:...
+       if err != nil || len(buf) == 0 {
+               return fmt.Errorf("gem env gempath: %v", err)
+       }
+       gempath := string(bytes.Split(buf, []byte{':'})[0])
+       boot.prependEnv("PATH", gempath+"/bin:")
+       boot.setEnv("GEM_HOME", gempath)
+       boot.setEnv("GEM_PATH", gempath)
+       return nil
+}
+
+func (boot *bootCommand) lookPath(prog string) string {
+       for _, val := range boot.environ {
+               if strings.HasPrefix(val, "PATH=") {
+                       for _, dir := range filepath.SplitList(val[5:]) {
+                               path := filepath.Join(dir, prog)
+                               if fi, err := os.Stat(path); err == nil && fi.Mode()&0111 != 0 {
+                                       return path
+                               }
+                       }
                }
-               gempath := string(bytes.Split(buf, []byte{':'})[0])
-               os.Setenv("PATH", gempath+"/bin:"+os.Getenv("PATH"))
-               os.Setenv("GEM_HOME", gempath)
-               os.Setenv("GEM_PATH", gempath)
-       })
-       return boot.setupRubyErr
+       }
+       return prog
 }
 
 // Run prog with args, using dir as working directory. If ctx is
@@ -259,7 +298,7 @@ func (boot *bootCommand) setupRubyEnv() error {
 func (boot *bootCommand) RunProgram(ctx context.Context, dir string, output io.Writer, env []string, prog string, args ...string) error {
        cmdline := fmt.Sprintf("%s", append([]string{prog}, args...))
        fmt.Fprintf(boot.stderr, "%s executing in %s\n", cmdline, dir)
-       cmd := exec.Command(prog, args...)
+       cmd := exec.Command(boot.lookPath(prog), args...)
        if output == nil {
                cmd.Stdout = boot.stderr
        } else {
@@ -271,9 +310,7 @@ func (boot *bootCommand) RunProgram(ctx context.Context, dir string, output io.W
        } else {
                cmd.Dir = filepath.Join(boot.sourcePath, dir)
        }
-       if env != nil {
-               cmd.Env = append(env, os.Environ()...)
-       }
+       cmd.Env = append(env, boot.environ...)
        go func() {
                <-ctx.Done()
                log := ctxlog.FromContext(ctx).WithFields(logrus.Fields{"dir": dir, "cmdline": cmdline})
@@ -318,7 +355,7 @@ func (cmpt *component) Run(ctx context.Context, boot *bootCommand, stdout, stder
                errs := make(chan error, 1)
                go func() {
                        defer close(errs)
-                       exitcode := cmpt.cmdHandler.RunCommand(cmpt.name, nil, bytes.NewBuffer(nil), stdout, stderr)
+                       exitcode := cmpt.cmdHandler.RunCommand(cmpt.name, []string{"-config", boot.configfile}, bytes.NewBuffer(nil), stdout, stderr)
                        if exitcode != 0 {
                                errs <- fmt.Errorf("exit code %d", exitcode)
                        }
@@ -365,10 +402,6 @@ func (cmpt *component) Run(ctx context.Context, boot *bootCommand, stdout, stder
                if err != nil {
                        return fmt.Errorf("bug: no InternalURLs for component %q: %v", cmpt.name, cmpt.svc.InternalURLs)
                }
-               err = boot.setupRubyEnv()
-               if err != nil {
-                       return err
-               }
                var buf bytes.Buffer
                err = boot.RunProgram(ctx, cmpt.railsApp, &buf, nil, "gem", "list", "--details", "bundler")
                if err != nil {