From cc4e48e0ec380f81a416da38a771f7a844982a80 Mon Sep 17 00:00:00 2001
From: Armon Dadgar <armon.dadgar@gmail.com>
Date: Thu, 2 Oct 2014 11:48:11 -0700
Subject: [PATCH] remote: Working on API client

---
 remote/client.go      | 114 ++++++++++++++++++++++++++++++++++++++++++
 remote/client_test.go |  76 ++++++++++++++++++++++++++++
 2 files changed, 190 insertions(+)
 create mode 100644 remote/client.go
 create mode 100644 remote/client_test.go

diff --git a/remote/client.go b/remote/client.go
new file mode 100644
index 000000000..8aee8aef7
--- /dev/null
+++ b/remote/client.go
@@ -0,0 +1,114 @@
+package remote
+
+import (
+	"bytes"
+	"crypto/md5"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"path"
+
+	"github.com/hashicorp/terraform/terraform"
+)
+
+// RemoteStatePayload is used to return the remote state
+// along with associated meta data when we do a remote fetch.
+type RemoteStatePayload struct {
+	MD5 []byte
+	R   io.Reader
+}
+
+// GetState is used to read the remote state
+func GetState(conf *terraform.RemoteState) (*RemoteStatePayload, error) {
+	// Get the base URL configuration
+	base, err := url.Parse(conf.Server)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to parse remote server '%s': %v", conf.Server, err)
+	}
+
+	// Compute the full path by just appending the name
+	base.Path = path.Join(base.Path, conf.Name)
+
+	// Add the request token if any
+	if conf.AuthToken != "" {
+		values := base.Query()
+		values.Set("access_token", conf.AuthToken)
+		base.RawQuery = values.Encode()
+	}
+
+	// Request the url
+	resp, err := http.Get(base.String())
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	// Handle the common status codes
+	switch resp.StatusCode {
+	case http.StatusOK:
+		// Handled after
+	case http.StatusNoContent:
+		return nil, nil
+	case http.StatusNotFound:
+		return nil, nil
+	case http.StatusUnauthorized:
+		return nil, fmt.Errorf("Remote server requires authentication")
+	case http.StatusForbidden:
+		return nil, fmt.Errorf("Invalid authentication token")
+	case http.StatusInternalServerError:
+		return nil, fmt.Errorf("Remote server reporting internal error")
+	default:
+		return nil, fmt.Errorf("Received unexpected HTTP response code %d", resp.StatusCode)
+	}
+
+	// Read in the body
+	buf := bytes.NewBuffer(nil)
+	if _, err := io.Copy(buf, resp.Body); err != nil {
+		return nil, fmt.Errorf("Failed to read remote state: %v", err)
+	}
+
+	// Create the payload
+	payload := &RemoteStatePayload{
+		R: buf,
+	}
+
+	// Check if this is Consul
+	if raw := resp.Header.Get("X-Consul-Index"); raw != "" {
+		// Check if we used the ?raw query param, otherwise decode
+		if _, ok := base.Query()["raw"]; !ok {
+			type kv struct {
+				Value []byte
+			}
+			var values []*kv
+			if err := json.Unmarshal(buf.Bytes(), &values); err != nil {
+				return nil, fmt.Errorf("Failed to decode Consul response: %v", err)
+			}
+
+			// Setup the reader to pull the value from Consul
+			payload.R = bytes.NewReader(values[0].Value)
+
+			// Generate the MD5
+			hash := md5.Sum(values[0].Value)
+			payload.MD5 = hash[:md5.Size]
+		}
+	}
+
+	// Check for the MD5
+	if raw := resp.Header.Get("Content-MD5"); raw != "" {
+		md5, err := base64.StdEncoding.DecodeString(raw)
+		if err != nil {
+			return nil, fmt.Errorf("Failed to decode Content-MD5 '%s': %v", raw, err)
+		}
+		payload.MD5 = md5
+
+	} else if _, ok := payload.R.(*bytes.Buffer); ok {
+		// Generate the MD5
+		hash := md5.Sum(buf.Bytes())
+		payload.MD5 = hash[:md5.Size]
+	}
+
+	return payload, nil
+}
diff --git a/remote/client_test.go b/remote/client_test.go
new file mode 100644
index 000000000..73a5e6e48
--- /dev/null
+++ b/remote/client_test.go
@@ -0,0 +1,76 @@
+package remote
+
+import (
+	"bytes"
+	"crypto/md5"
+	"io"
+	"net/http"
+	"strings"
+	"testing"
+
+	"github.com/armon/consul-api"
+	"github.com/hashicorp/terraform/terraform"
+)
+
+var haveInternet bool
+
+func init() {
+	// Use google to check if we are on the net
+	_, err := http.Get("http://www.google.com")
+	haveInternet = (err == nil)
+}
+
+func TestGetState_Consul(t *testing.T) {
+	if !haveInternet {
+		t.SkipNow()
+	}
+
+	// Use the Consul demo cluster
+	conf := consulapi.DefaultConfig()
+	conf.Address = "demo.consul.io:80"
+	client, err := consulapi.NewClient(conf)
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	// Write some test data
+	pair := &consulapi.KVPair{
+		Key:   "test/tf/remote/foobar",
+		Value: []byte("testing"),
+	}
+	kv := client.KV()
+	if _, err := kv.Put(pair, nil); err != nil {
+		t.Fatalf("err: %v", err)
+	}
+	defer kv.Delete(pair.Key, nil)
+
+	// Check we can get the state
+	remote := &terraform.RemoteState{
+		Name:   "foobar",
+		Server: "http://demo.consul.io/v1/kv/test/tf/remote",
+	}
+REQ:
+	payload, err := GetState(remote)
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	// Check the MD5
+	expect := md5.Sum(pair.Value)
+	if !bytes.Equal(payload.MD5, expect[:md5.Size]) {
+		t.Fatalf("Bad md5")
+	}
+
+	// Check the body
+	var buf bytes.Buffer
+	io.Copy(&buf, payload.R)
+	if string(buf.Bytes()) != "testing" {
+		t.Fatalf("Bad body")
+	}
+
+	// Try doing a ?raw lookup
+	if !strings.Contains(remote.Server, "?raw") {
+		remote.Server += "?raw"
+		goto REQ
+	}
+}