cmd/juju: simplify testing infrastructure.

juju/testing/conn.go

Index: juju/testing/conn.go
=== modified file 'juju/testing/conn.go'
--- juju/testing/conn.go	2012-08-23 15:13:31 +0000
+++ juju/testing/conn.go	2012-08-29 13:13:38 +0000
@@ -2,24 +2,45 @@
 
 import (
 	"fmt"
+	"io/ioutil"
 	. "launchpad.net/gocheck"
 	"launchpad.net/juju-core/charm"
+	"launchpad.net/juju-core/environs"
 	"launchpad.net/juju-core/environs/dummy"
 	"launchpad.net/juju-core/juju"
 	state "launchpad.net/juju-core/state"
 	"launchpad.net/juju-core/testing"
 	"net/url"
+	"os"
+	"path/filepath"
 )
 
 // JujuConnSuite provides a freshly bootstrapped juju.Conn
 // for each test. It also includes testing.LoggingSuite.
+//
+// It also sets up $HOME and environs.VarDir to
+// temporary directories; the former is primed to
+// hold the dummy environments.yaml file.
+//
+// The name of the dummy environment is "dummyenv".
 type JujuConnSuite struct {
 	testing.LoggingSuite
 	testing.ZkSuite
-	Conn  *juju.Conn
-	State *state.State
+	Conn      *juju.Conn
+	State     *state.State
+	rootDir   string // the faked-up root directory.
+	oldHome   string
+	oldVarDir string
 }
 
+var config = []byte(`
+environments:
+    dummyenv:
+        type: dummy
+        zookeeper: true
+        authorized-keys: 'i-am-a-key'
+`)
+
 func (s *JujuConnSuite) SetUpTest(c *C) {
 	s.LoggingSuite.SetUpTest(c)
 	s.setUpConn(c)
@@ -37,6 +58,64 @@
 	s.setUpConn(c)
 }
 
+func (s *JujuConnSuite) setUpConn(c *C) {
+	if s.rootDir != "" {
+		panic("JujuConnSuite.setUpConn without teardown")
+	}
+	s.rootDir = c.MkDir()
+	s.oldHome = os.Getenv("HOME")
+	home := filepath.Join(s.rootDir, "/home/ubuntu")
+	err := os.MkdirAll(home, 0777)
+	c.Assert(err, IsNil)
+	os.Setenv("HOME", home)
+
+	s.oldVarDir = environs.VarDir
+	varDir := filepath.Join(s.rootDir, environs.VarDir)
+	err = os.MkdirAll(varDir, 0777)
+	c.Assert(err, IsNil)
+	environs.VarDir = varDir
+
+	err = os.Mkdir(filepath.Join(home, ".juju"), 0777)
+	c.Assert(err, IsNil)
+
+	err = ioutil.WriteFile(filepath.Join(home, ".juju", "environments.yaml"), config, 0600)
+	c.Assert(err, IsNil)
+	conn, err := juju.NewConn("dummyenv")
+	c.Assert(err, IsNil)
+
+	// sanity check we've got the correct environment.
+	c.Assert(conn.Environ.Name(), Equals, "dummyenv")
+
+	c.Assert(conn.Bootstrap(false), IsNil)
+	s.Conn = conn
+	s.State, err = conn.State()
+	c.Assert(err, IsNil)
+}
+
+func (s *JujuConnSuite) tearDownConn(c *C) {
+	dummy.Reset()
+	c.Assert(s.Conn.Close(), IsNil)
+	s.Conn = nil
+	s.State = nil
+	os.Setenv("HOME", s.oldHome)
+	s.oldHome = ""
+	environs.VarDir = s.oldVarDir
+	s.oldVarDir = ""
+	s.rootDir = ""
+}
+
+// WriteConfig writes a juju config file to the "home" directory.
+func (s *JujuConnSuite) WriteConfig(config string) {
+	if s.rootDir == "" {
+		panic("SetUpTest has not been called; will not overwrite $HOME/.juju/environments.yaml")
+	}
+	path := filepath.Join(os.Getenv("HOME"), ".juju", "environments.yaml")
+	err := ioutil.WriteFile(path, []byte(config), 0600)
+	if err != nil {
+		panic(err)
+	}
+}
+
 func (s *JujuConnSuite) StateInfo(c *C) *state.Info {
 	return &state.Info{Addrs: []string{testing.ZkAddr}}
 }
@@ -51,26 +130,3 @@
 	c.Assert(err, IsNil)
 	return sch
 }
-
-func (s *JujuConnSuite) setUpConn(c *C) {
-	config := map[string]interface{}{
-		"name":            "foo",
-		"type":            "dummy",
-		"zookeeper":       true,
-		"authorized-keys": "i-am-a-key",
-	}
-	conn, err := juju.NewConnFromAttrs(config)
-	c.Assert(err, IsNil)
-
-	c.Assert(conn.Bootstrap(false), IsNil)
-	s.Conn = conn
-	s.State, err = conn.State()
-	c.Assert(err, IsNil)
-}
-
-func (s *JujuConnSuite) tearDownConn(c *C) {
-	dummy.Reset()
-	c.Assert(s.Conn.Close(), IsNil)
-	s.Conn = nil
-	s.State = nil
-}