cmd/juju: working bootstrap and destroy commands

store/charmload/main.go

 package main
 
 import (
         "fmt"
+        "io/ioutil"
+        "launchpad.net/goyaml"
         "launchpad.net/juju/go/log"
         "launchpad.net/juju/go/store"
         "launchpad.net/lpad"
         stdlog "log"
         "os"
         "path/filepath"
 )
 
 func main() {
         log.Target = stdlog.New(os.Stdout, "", stdlog.LstdFlags)
         err := load()
         if err != nil {
                 fmt.Fprintf(os.Stderr, "%v\n", err)
                 os.Exit(1)
         }
 }
 
+type config struct {
+        MongoURL string `yaml:"mongo-url"`
+}
+
+func readConfig(path string, conf interface{}) error {
+        f, err := os.Open(path)
+        if err != nil {
+                return fmt.Errorf("opening config file: %v", err)
+        }
+        data, err := ioutil.ReadAll(f)
+        f.Close()
+        if err != nil {
+                return fmt.Errorf("reading config file: %v", err)
+        }
+        err = goyaml.Unmarshal(data, conf)
+        if err != nil {
+                return fmt.Errorf("processing config file: %v", err)
+        }
+        return nil
+}
+
 func load() error {
-        if len(os.Args) != 2 || len(os.Args[1]) == 0 || os.Args[1][0] == '-' {
-                return fmt.Errorf("usage: %s <mongo addr>", filepath.Base(os.Args[0]))
+        var confPath string
+        if len(os.Args) == 2 {
+                if _, err := os.Stat(os.Args[1]); err == nil {
+                        confPath = os.Args[1]
+                }
         }
-        s, err := store.Open(os.Args[1])
+        if confPath == "" {
+                return fmt.Errorf("usage: %s <config path>", filepath.Base(os.Args[0]))
+        }
+        var conf config
+        err := readConfig(confPath, &conf)
         if err != nil {
                 return err
         }
+        if conf.MongoURL == "" {
+                return fmt.Errorf("missing mongo-url in config file")
+        }
+        s, err := store.Open(conf.MongoURL)
+        if err != nil {
+                return err
+        }
         defer s.Close()
         err = store.PublishCharmsDistro(s, lpad.Production)
         if _, ok := err.(store.PublishBranchErrors); ok {
                 // Ignore branch errors since they're commonplace here.
                 // They're logged, though.
                 return nil
         }
         return err
 }