rest: Implement MarkSeen for #58

- message: Add MarkSeen to Manager, StoreManager.
- rest: Add PATCH for /mailbox/name/id.
- rest: Add MailboxMarkSeenV1 handler.
- rest: Add Seen to model.
- rest: Update handlers to set Seen.
- rest: Add doJSONBody func.

pkg/rest/client/rest.go

@@ -1,8 +1,10 @@
 package client
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
+	"io"
 	"net/http"
 	"net/url"
 )
@@ -18,28 +20,48 @@ type restClient struct {
 	baseURL *url.URL
 }
 
-// do performs an HTTP request with this client and returns the response
-func (c *restClient) do(method, uri string) (*http.Response, error) {
+// do performs an HTTP request with this client and returns the response.
+func (c *restClient) do(method, uri string, body []byte) (*http.Response, error) {
 	rel, err := url.Parse(uri)
 	if err != nil {
 		return nil, err
 	}
-
 	url := c.baseURL.ResolveReference(rel)
-
-	// Build the request
-	req, err := http.NewRequest(method, url.String(), nil)
+	var r io.Reader
+	if body != nil {
+		r = bytes.NewReader(body)
+	}
+	req, err := http.NewRequest(method, url.String(), r)
 	if err != nil {
 		return nil, err
 	}
-
-	// Send the request
 	return c.client.Do(req)
 }
 
-// doGet performs an HTTP request with this client and marshalls the JSON response into v
+// doJSON performs an HTTP request with this client and marshalls the JSON response into v.
 func (c *restClient) doJSON(method string, uri string, v interface{}) error {
-	resp, err := c.do(method, uri)
+	resp, err := c.do(method, uri, nil)
+	if err != nil {
+		return err
+	}
+
+	defer func() {
+		_ = resp.Body.Close()
+	}()
+	if resp.StatusCode == http.StatusOK {
+		if v == nil {
+			return nil
+		}
+		// Decode response body
+		return json.NewDecoder(resp.Body).Decode(v)
+	}
+
+	return fmt.Errorf("Unexpected HTTP response status %v: %s", resp.StatusCode, resp.Status)
+}
+
+// doJSONBody performs an HTTP request with this client and marshalls the JSON response into v.
+func (c *restClient) doJSONBody(method string, uri string, body []byte, v interface{}) error {
+	resp, err := c.do(method, uri, body)
 	if err != nil {
 		return err
 	}