Expand env variables to job mount path

jsturtevant · jsturtevant · commit 014849a4b0dc · 2022-02-03T14:30:32.000-08:00
When installing tools into container it is sometimes desirable to have
those tools on the path for the current process.  Since the Windows
doesn't support variable expansion on the PATH variable and the
job mount path as something that isn't know at runtime we need to expand
it for the passer.  This could go away if the mount path is no longer
used in the future.

Signed-off-by: James Sturtevant &lt;jsturtevant@gmail.com&gt;
diff --git a/internal/jobcontainers/jobcontainer.go b/internal/jobcontainers/jobcontainer.go
@@ -39,15 +39,6 @@ func splitArgs(cmdLine string) []string {
 	return r.FindAllString(cmdLine, -1)
 }
 
-// Convert environment map to a slice of environment variables in the form [Key1=val1, key2=val2]
-func envMapToSlice(m map[string]string) []string {
-	var s []string
-	for k, v := range m {
-		s = append(s, k+"="+v)
-	}
-	return s
-}
-
 const (
 	jobContainerNameFmt = "JobContainer_%s"
 	// Environment variable set in every process in the job detailing where the containers volume
@@ -232,7 +223,15 @@ func (c *JobContainer) CreateProcess(ctx context.Context, config interface{}) (_
 	if err != nil {
 		return nil, errors.Wrap(err, "failed to get default environment block")
 	}
-	env = append(env, envMapToSlice(conf.Environment)...)
+
+	// Convert environment map to a slice of environment variables in the form [Key1=val1, key2=val2]
+	var envs []string
+	for k, v := range conf.Environment {
+		expanded, _ := c.replaceWithMountPoint(v)
+		envs = append(envs, k+"="+expanded)
+	}
+	env = append(env, envs...)
+
 	env = append(env, sandboxMountPointEnvVar+"="+c.sandboxMount)
 
 	// exec.Cmd internally does its own path resolution and as part of this checks some well known file extensions on the file given (e.g. if
@@ -603,7 +602,7 @@ func systemProcessInformation() ([]*winapi.SYSTEM_PROCESS_INFORMATION, error) {
 	return procInfos, nil
 }
 
-// Takes a string and replaces any occurences of CONTAINER_SANDBOX_MOUNT_POINT with where the containers volume is mounted, as well as returning
+// Takes a string and replaces any occurrences of CONTAINER_SANDBOX_MOUNT_POINT with where the containers' volume is mounted, as well as returning
 // if the string actually contained the environment variable.
 func (c *JobContainer) replaceWithMountPoint(str string) (string, bool) {
 	newStr := strings.ReplaceAll(str, "%"+sandboxMountPointEnvVar+"%", c.sandboxMount[:len(c.sandboxMount)-1])
