Cope when item in .lastDone does not exist (anymore)

Also update chromedp to 0.5.4, so we can benefit from conveniences such
as RunResponse (which is relied upon for this fix).
Consequently, that means a recent enough Chrome version (v83) is needed
as per this commit.
See chromedp/chromedp#627

Fixes #17

go.mod

@@ -3,6 +3,6 @@ module github.com/perkeep/gphotos-cdp
 go 1.12
 
 require (
-	github.com/chromedp/cdproto v0.0.0-20190812224334-39ef923dcb8d
-	github.com/chromedp/chromedp v0.4.0
+	github.com/chromedp/cdproto v0.0.0-20200608134039-8a80cdaf865c
+	github.com/chromedp/chromedp v0.5.4-0.20200624114048-353306f986a8
 )

go.sum

@@ -1,16 +1,35 @@
 github.com/chromedp/cdproto v0.0.0-20190812224334-39ef923dcb8d h1:00kLGv5nKzpFchNhGDXDRbKtYx/WoT983Ka2t8/pzRE=
 github.com/chromedp/cdproto v0.0.0-20190812224334-39ef923dcb8d/go.mod h1:0YChpVzuLJC5CPr+x3xkHN6Z8KOSXjNbL7qV8Wc4GW0=
+github.com/chromedp/cdproto v0.0.0-20200116234248-4da64dd111ac h1:T7V5BXqnYd55Hj/g5uhDYumg9Fp3rMTS6bykYtTIFX4=
+github.com/chromedp/cdproto v0.0.0-20200116234248-4da64dd111ac/go.mod h1:PfAWWKJqjlGFYJEidUM6aVIWPr0EpobeyVWEEmplX7g=
+github.com/chromedp/cdproto v0.0.0-20200209033844-7e00b02ea7d2/go.mod h1:PfAWWKJqjlGFYJEidUM6aVIWPr0EpobeyVWEEmplX7g=
+github.com/chromedp/cdproto v0.0.0-20200608134039-8a80cdaf865c h1:qM1xzKK8kc93zKPkxK4iqtjksqDDrU6g9wGnr30jyLo=
+github.com/chromedp/cdproto v0.0.0-20200608134039-8a80cdaf865c/go.mod h1:E6LPWRdIJc11h/di5p0rwvRmUYbhGpBEH7ZbPfzDIOE=
 github.com/chromedp/chromedp v0.4.0 h1:0AJC5ejETuh/6n7Tcsw4u4G0eKZkI9aVRwckWaImLUE=
 github.com/chromedp/chromedp v0.4.0/go.mod h1:DC3QUn4mJ24dwjcaGQLoZrhm4X/uPHZ6spDbS2uFhm4=
+github.com/chromedp/chromedp v0.5.3 h1:F9LafxmYpsQhWQBdCs+6Sret1zzeeFyHS5LkRF//Ffg=
+github.com/chromedp/chromedp v0.5.3/go.mod h1:YLdPtndaHQ4rCpSpBG+IPpy9JvX0VD+7aaLxYgYj28w=
+github.com/chromedp/chromedp v0.5.4-0.20200624114048-353306f986a8 h1:JU/73ZWIwh2HUPEt1pFKoVOhT8hMS6Q9WQ382v0WUjI=
+github.com/chromedp/chromedp v0.5.4-0.20200624114048-353306f986a8/go.mod h1:fIICWzcY8T8pfGlPyweJ5MNnBi2dGZgoRn/t4BOu7gA=
 github.com/gobwas/httphead v0.0.0-20180130184737-2c6c146eadee h1:s+21KNqlpePfkah2I+gwHF8xmJWRjooY+5248k6m4A0=
 github.com/gobwas/httphead v0.0.0-20180130184737-2c6c146eadee/go.mod h1:L0fX3K22YWvt/FAX9NnzrNzcI4wNYi9Yku4O0LKYflo=
 github.com/gobwas/pool v0.2.0 h1:QEmUOlnSjWtnpRGHF3SauEiOsy82Cup83Vf2LcMlnc8=
 github.com/gobwas/pool v0.2.0/go.mod h1:q8bcK0KcYlCgd9e7WYLm9LpyS+YeLd8JVDW6WezmKEw=
 github.com/gobwas/ws v1.0.2 h1:CoAavW/wd/kulfZmSIBt6p24n4j7tHgNVCjsfHVNUbo=
 github.com/gobwas/ws v1.0.2/go.mod h1:szmBTxLgaFppYjEmNtny/v3w89xOydFnnZMcgRRu/EM=
+github.com/gobwas/ws v1.0.3 h1:ZOigqf7iBxkA4jdQ3am7ATzdlOFp9YzA6NmuvEEZc9g=
+github.com/gobwas/ws v1.0.3/go.mod h1:szmBTxLgaFppYjEmNtny/v3w89xOydFnnZMcgRRu/EM=
 github.com/knq/sysutil v0.0.0-20181215143952-f05b59f0f307 h1:vl4eIlySbjertFaNwiMjXsGrFVK25aOWLq7n+3gh2ls=
 github.com/knq/sysutil v0.0.0-20181215143952-f05b59f0f307/go.mod h1:BjPj+aVjl9FW/cCGiF3nGh5v+9Gd3VCgBQbod/GlMaQ=
+github.com/knq/sysutil v0.0.0-20191005231841-15668db23d08 h1:V0an7KRw92wmJysvFvtqtKMAPmvS5O0jtB0nYo6t+gs=
+github.com/knq/sysutil v0.0.0-20191005231841-15668db23d08/go.mod h1:dFWs1zEqDjFtnBXsd1vPOZaLsESovai349994nHx3e0=
 github.com/mailru/easyjson v0.0.0-20190626092158-b2ccc519800e h1:hB2xlXdHp/pmPZq0y3QnmWAArdw9PqbmotexnWx/FU8=
 github.com/mailru/easyjson v0.0.0-20190626092158-b2ccc519800e/go.mod h1:C1wdFJiN94OJF2b5HbByQZoLdCWB1Yqtg26g4irojpc=
+github.com/mailru/easyjson v0.7.0 h1:aizVhC/NAAcKWb+5QsU1iNOZb4Yws5UO2I+aIprQITM=
+github.com/mailru/easyjson v0.7.0/go.mod h1:KAzv3t3aY1NaHWoQz1+4F1ccyAH66Jk7yos7ldAVICs=
+github.com/mailru/easyjson v0.7.1 h1:mdxE1MF9o53iCb2Ghj1VfWvh7ZOwHpnVG/xwXrV90U8=
+github.com/mailru/easyjson v0.7.1/go.mod h1:KAzv3t3aY1NaHWoQz1+4F1ccyAH66Jk7yos7ldAVICs=
 golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a h1:aYOabOQFp6Vj6W1F80affTUvO9UxmJRx8K0gsfABByQ=
 golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200116001909-b77594299b42 h1:vEOn+mP2zCOVzKckCZy6YsCtDblrpj/w7B9nxGNELpg=
+golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=

main.go

@@ -26,6 +26,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"log"
+	"net/http"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -34,6 +35,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/chromedp/cdproto/browser"
 	"github.com/chromedp/cdproto/input"
 	"github.com/chromedp/cdproto/page"
 	"github.com/chromedp/chromedp"
@@ -190,6 +192,9 @@ func (s *Session) cleanDlDir() error {
 		if v.IsDir() {
 			continue
 		}
+		if v.Name() == ".lastdone" {
+			continue
+		}
 		if err := os.Remove(filepath.Join(s.dlDir, v.Name())); err != nil {
 			return err
 		}
@@ -201,7 +206,7 @@ func (s *Session) cleanDlDir() error {
 // authenticated (or for 2 minutes to have elapsed).
 func (s *Session) login(ctx context.Context) error {
 	return chromedp.Run(ctx,
-		page.SetDownloadBehavior(page.SetDownloadBehaviorBehaviorAllow).WithDownloadPath(s.dlDir),
+		browser.SetDownloadBehavior(browser.SetDownloadBehaviorBehaviorAllow).WithDownloadPath(s.dlDir),
 		chromedp.ActionFunc(func(ctx context.Context) error {
 			if *verboseFlag {
 				log.Printf("pre-navigate")
@@ -255,14 +260,40 @@ func (s *Session) firstNav(ctx context.Context) error {
 	}
 
 	if *startFlag != "" {
+		// TODO(mpl): use RunResponse
 		chromedp.Navigate(*startFlag).Do(ctx)
 		chromedp.WaitReady("body", chromedp.ByQuery).Do(ctx)
 		return nil
 	}
 	if s.lastDone != "" {
-		chromedp.Navigate(s.lastDone).Do(ctx)
+		resp, err := chromedp.RunResponse(ctx, chromedp.Navigate(s.lastDone))
+		if err != nil {
+			return err
+		}
+		if resp.Status == http.StatusOK {
+			chromedp.WaitReady("body", chromedp.ByQuery).Do(ctx)
+			return nil
+		}
+		lastDoneFile := filepath.Join(s.dlDir, ".lastdone")
+		log.Printf("%s does not seem to exist anymore. Removing %s.", s.lastDone, lastDoneFile)
+		s.lastDone = ""
+		if err := os.Remove(lastDoneFile); err != nil {
+			if os.IsNotExist(err) {
+				log.Fatal("Failed to remove .lastdone file because it was already gone.")
+			}
+			return err
+		}
+
+		// restart from scratch
+		resp, err = chromedp.RunResponse(ctx, chromedp.Navigate("https://photos.google.com/"))
+		if err != nil {
+			return err
+		}
+		code := resp.Status
+		if code != http.StatusOK {
+			return fmt.Errorf("unexpected %d code when restarting to https://photos.google.com/", code)
+		}
 		chromedp.WaitReady("body", chromedp.ByQuery).Do(ctx)
-		return nil
 	}
 
 	if err := navToEnd(ctx); err != nil {