feat: Add TLS support (#556)

* feat: Add TLS support

This adds numerous flags with inspiration taken from Vault
for configuring TLS inside Coder.

This enables secure deployments without a proxy, like Cloudflare.

* Update cli/start.go

Co-authored-by: Colin Adler <colin@coder.com>

* Fix flag help in coder.env

Co-authored-by: Colin Adler <colin@coder.com>

codersdk/client.go

@@ -21,16 +21,15 @@ import (
 func New(serverURL *url.URL) *Client {
 	return &Client{
 		URL:        serverURL,
-		httpClient: &http.Client{},
+		HTTPClient: &http.Client{},
 	}
 }
 
 // Client is an HTTP caller for methods to the Coder API.
 type Client struct {
-	URL          *url.URL
+	HTTPClient   *http.Client
 	SessionToken string
-
-	httpClient *http.Client
+	URL          *url.URL
 }
 
 // request performs an HTTP request with the body provided.
@@ -71,7 +70,7 @@ func (c *Client) request(ctx context.Context, method, path string, body interfac
 		opt(req)
 	}
 
-	resp, err := c.httpClient.Do(req)
+	resp, err := c.HTTPClient.Do(req)
 	if err != nil {
 		return nil, xerrors.Errorf("do: %w", err)
 	}

codersdk/provisionerdaemons.go

@@ -59,7 +59,7 @@ func (c *Client) ListenProvisionerDaemon(ctx context.Context) (proto.DRPCProvisi
 		return nil, xerrors.Errorf("parse url: %w", err)
 	}
 	conn, res, err := websocket.Dial(ctx, serverURL.String(), &websocket.DialOptions{
-		HTTPClient: c.httpClient,
+		HTTPClient: c.HTTPClient,
 		// Need to disable compression to avoid a data-race.
 		CompressionMode: websocket.CompressionDisabled,
 	})

codersdk/workspaceresourceauth.go

@@ -30,7 +30,7 @@ func (c *Client) AuthWorkspaceGoogleInstanceIdentity(ctx context.Context, servic
 		serviceAccount = "default"
 	}
 	if gcpClient == nil {
-		gcpClient = metadata.NewClient(c.httpClient)
+		gcpClient = metadata.NewClient(c.HTTPClient)
 	}
 	// "format=full" is required, otherwise the responding payload will be missing "instance_id".
 	jwt, err := gcpClient.Get(fmt.Sprintf("instance/service-accounts/%s/identity?audience=coder&format=full", serviceAccount))