state/remote: add HTTP client

state/remote/http.go

@@ -0,0 +1,156 @@
+package remote
+
+import (
+	"bytes"
+	"crypto/md5"
+	"encoding/base64"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+)
+
+func httpFactory(conf map[string]string) (Client, error) {
+	address, ok := conf["address"]
+	if !ok {
+		return nil, fmt.Errorf("missing 'address' configuration")
+	}
+
+	url, err := url.Parse(address)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse HTTP URL: %s", err)
+	}
+	if url.Scheme != "http" && url.Scheme != "https" {
+		return nil, fmt.Errorf("address must be HTTP or HTTPS")
+	}
+
+	return &HTTPClient{
+		URL: url,
+	}, nil
+}
+
+// HTTPClient is a remote client that stores data in Consul.
+type HTTPClient struct {
+	URL *url.URL
+}
+
+func (c *HTTPClient) Get() (*Payload, error) {
+	resp, err := http.Get(c.URL.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("HTTP remote state endpoint requires auth")
+	case http.StatusForbidden:
+		return nil, fmt.Errorf("HTTP remote state endpoint invalid auth")
+	case http.StatusInternalServerError:
+		return nil, fmt.Errorf("HTTP remote state internal server error")
+	default:
+		return nil, fmt.Errorf("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: %s", err)
+	}
+
+	// Create the payload
+	payload := &Payload{
+		Data: buf.Bytes(),
+	}
+
+	// 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': %s", raw, err)
+		}
+
+		payload.MD5 = md5
+	} else {
+		// Generate the MD5
+		hash := md5.Sum(payload.Data)
+		payload.MD5 = hash[:]
+	}
+
+	return payload, nil
+}
+
+func (c *HTTPClient) Put(data []byte) error {
+	// Copy the target URL
+	base := *c.URL
+
+	// Generate the MD5
+	hash := md5.Sum(data)
+	b64 := base64.StdEncoding.EncodeToString(hash[:])
+
+	/*
+		// Set the force query parameter if needed
+		if force {
+			values := base.Query()
+			values.Set("force", "true")
+			base.RawQuery = values.Encode()
+		}
+	*/
+
+	// Make the HTTP client and request
+	req, err := http.NewRequest("POST", base.String(), bytes.NewReader(data))
+	if err != nil {
+		return fmt.Errorf("Failed to make HTTP request: %s", err)
+	}
+
+	// Prepare the request
+	req.Header.Set("Content-Type", "application/octet-stream")
+	req.Header.Set("Content-MD5", b64)
+	req.ContentLength = int64(len(data))
+
+	// Make the request
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return fmt.Errorf("Failed to upload state: %v", err)
+	}
+	defer resp.Body.Close()
+
+	// Handle the error codes
+	switch resp.StatusCode {
+	case http.StatusOK:
+		return nil
+	default:
+		return fmt.Errorf("HTTP error: %d", resp.StatusCode)
+	}
+}
+
+func (c *HTTPClient) Delete() error {
+	// Make the HTTP request
+	req, err := http.NewRequest("DELETE", c.URL.String(), nil)
+	if err != nil {
+		return fmt.Errorf("Failed to make HTTP request: %s", err)
+	}
+
+	// Make the request
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return fmt.Errorf("Failed to delete state: %s", err)
+	}
+	defer resp.Body.Close()
+
+	// Handle the error codes
+	switch resp.StatusCode {
+	case http.StatusOK:
+		return nil
+	default:
+		return fmt.Errorf("HTTP error: %d", resp.StatusCode)
+	}
+}

state/remote/http_test.go

@@ -0,0 +1,14 @@
+package remote
+
+import (
+	"testing"
+)
+
+func TestHTTPClient_impl(t *testing.T) {
+	var _ Client = new(HTTPClient)
+}
+
+func TestHTTPClient(t *testing.T) {
+	// TODO
+	//testClient(t, client)
+}

state/remote/remote.go

@@ -37,4 +37,5 @@ func NewClient(t string, conf map[string]string) (Client, error) {
 // NewClient.
 var BuiltinClients = map[string]Factory{
 	"consul": consulFactory,
+	"http":   httpFactory,
 }