Golang Context.Criticalf方法代碼示例

func CFix(c mpg.Context, w http.ResponseWriter, r *http.Request) {
	gn := goon.FromContext(c)
	url := r.FormValue("feed")
	c.Infof("fix feed %s", url)
	f := Feed{Url: url}
	if err := gn.Get(&f); err != nil {
		c.Criticalf("cfix err: %v", err)
		serveError(w, err)
		return
	}

	q := datastore.NewQuery("S").Ancestor(gn.Key(&f))
	var ss []*Story
	keys, err := q.GetAll(c, &ss)
	if err != nil {
		c.Errorf("getall err: %v", err)
		serveError(w, err)
		return
	}
	c.Infof("trying to fix %v stories", len(ss))
	const putLimit = 500
	for i := 0; i <= len(keys)/putLimit; i++ {
		lo := i * putLimit
		hi := (i + 1) * putLimit
		if hi > len(keys) {
			hi = len(keys)
		}
		c.Infof("%v - %v", lo, hi)
		if _, err := datastore.PutMulti(c, keys[lo:hi], ss[lo:hi]); err != nil {
			c.Errorf("err: %v, %v, %v", lo, hi, err)
		}
	}
}

func DeleteOldFeed(c mpg.Context, w http.ResponseWriter, r *http.Request) {
	g := goon.FromContext(c)
	oldDate := time.Now().Add(-time.Hour * 24 * 90)
	feed := Feed{Url: r.FormValue("f")}
	if err := g.Get(&feed); err != nil {
		c.Criticalf("err: %v", err)
		return
	}
	if feed.LastViewed.After(oldDate) {
		return
	}
	q := datastore.NewQuery(g.Kind(&Story{})).Ancestor(g.Key(&feed)).KeysOnly()
	keys, err := q.GetAll(c, nil)
	if err != nil {
		c.Criticalf("err: %v", err)
		return
	}
	q = datastore.NewQuery(g.Kind(&StoryContent{})).Ancestor(g.Key(&feed)).KeysOnly()
	sckeys, err := q.GetAll(c, nil)
	if err != nil {
		c.Criticalf("err: %v", err)
		return
	}
	keys = append(keys, sckeys...)
	c.Infof("delete: %v - %v", feed.Url, len(keys))
	err = g.DeleteMulti(keys)
	if err != nil {
		c.Criticalf("err: %v", err)
	}
}

func BackendStart(c mpg.Context, w http.ResponseWriter, r *http.Request) {
	return
	const sz = 100
	ic := 0
	var f func(appengine.Context)
	var cs string
	f = func(c appengine.Context) {
		gn := goon.FromContext(c)
		c.Errorf("ic: %d", ic)
		wg := sync.WaitGroup{}
		wg.Add(sz)
		var j int64
		q := datastore.NewQuery("F").KeysOnly()
		if cs != "" {
			if cur, err := datastore.DecodeCursor(cs); err == nil {
				q = q.Start(cur)
				c.Errorf("cur start: %v", cur)
			}
		}
		it := q.Run(c)
		for j = 0; j < sz; j++ {
			k, err := it.Next(nil)
			c.Errorf("%v: %v, %v", j, k, err)
			if err != nil {
				c.Criticalf("err: %v", err)
				return
			}

			go func(k *datastore.Key) {
				f := Feed{Url: k.StringID()}
				if err := gn.Get(&f); err == nil {
					f.Subscribe(c)
				}

				wg.Done()
			}(k)
		}
		cur, err := it.Cursor()
		if err == nil {
			cs = cur.String()
		}
		wg.Wait()
		ic++
		runtime.RunInBackground(c, f)
	}
	runtime.RunInBackground(c, f)
}

func fetchFeed(c mpg.Context, origUrl, fetchUrl string) (*Feed, []*Story) {
	u, err := url.Parse(fetchUrl)
	_orig := origUrl
	if err == nil && u.Scheme == "" {
		u.Scheme = "http"
		origUrl = u.String()
		fetchUrl = origUrl
		if origUrl == "" {
			c.Criticalf("badurl1: %v, %v, %v, %v", _orig, u, origUrl, fetchUrl)
			return nil, nil
		}
	}
	if strings.TrimSpace(origUrl) == "" {
		c.Criticalf("badurl2: %v, %v", _orig, origUrl)
		return nil, nil
	}

	cl := &http.Client{
		Transport: &urlfetch.Transport{
			Context:  c,
			Deadline: time.Minute,
		},
	}
	if resp, err := cl.Get(fetchUrl); err == nil && resp.StatusCode == http.StatusOK {
		defer resp.Body.Close()
		b, _ := ioutil.ReadAll(resp.Body)
		if autoUrl, err := Autodiscover(b); err == nil && origUrl == fetchUrl {
			if autoU, err := url.Parse(autoUrl); err == nil {
				if autoU.Scheme == "" {
					autoU.Scheme = u.Scheme
				}
				if autoU.Host == "" {
					autoU.Host = u.Host
				}
				autoUrl = autoU.String()
			}
			return fetchFeed(c, origUrl, autoUrl)
		}
		return ParseFeed(c, origUrl, b)
	} else if err != nil {
		c.Warningf("fetch feed error: %s", err.Error())
	} else {
		c.Warningf("fetch feed error: status code: %s", resp.Status)
	}
	return nil, nil
}

func UpdateFeed(c mpg.Context, w http.ResponseWriter, r *http.Request) {
	gn := goon.FromContext(c)
	url := r.FormValue("feed")
	c.Debugf("update feed %s", url)
	f := Feed{Url: url}
	if err := gn.Get(&f); err == datastore.ErrNoSuchEntity {
		c.Errorf("no such entity")
		return
	} else if err != nil {
		c.Errorf("badurl7 error: %v", err.Error())
		return
	} else if time.Now().Before(f.NextUpdate) {
		c.Infof("feed %v already updated", url)
		return
	}
	if f.Url == "" {
		c.Criticalf("badurl7: %v", url)
		return
	}

	feedError := func() {
		f.Errors++
		v := f.Errors + 1
		const max = 24 * 7
		if v > max {
			v = max
		} else if f.Errors == 1 {
			v = 0
		}
		f.NextUpdate = time.Now().Add(time.Hour * time.Duration(v))
		gn.Put(&f)
		c.Warningf("error with %v (%v), bump next update to %v", url, f.Errors, f.NextUpdate)
	}

	c.Infof("fetching")
	if feed, stories := fetchFeed(c, f.Url, f.Url); feed != nil {
		if err := updateFeed(c, f.Url, feed, stories); err != nil {
			feedError()
		}
	} else {
		feedError()
	}
	c.Infof("done")
}

func addFeed(c mpg.Context, userid string, outline *OpmlOutline) error {
	gn := goon.FromContext(c)
	o := outline.Outline[0]
	c.Infof("adding feed %v to user %s", o.XmlUrl, userid)

	f := Feed{Url: o.XmlUrl}
	if err := gn.Get(&f); err == datastore.ErrNoSuchEntity {
		if feed, stories := fetchFeed(c, o.XmlUrl, o.XmlUrl); feed == nil {
			return errors.New(fmt.Sprintf("could not add feed %s", o.XmlUrl))
		} else {
			f = *feed
			f.Updated = time.Time{}
			f.Checked = f.Updated
			f.NextUpdate = f.Updated
			if strings.TrimSpace(f.Url) == "" {
				c.Criticalf("badurl4: %v, %v", o.XmlUrl, o)
				return errors.New("badurl4")
			}
			gn.PutComplete(&f)
			if err := updateFeed(c, f.Url, feed, stories); err != nil {
				return err
			}

			o.XmlUrl = feed.Url
			o.HtmlUrl = feed.Link
			if o.Title == "" {
				o.Title = feed.Title
			}
		}
	} else if err != nil {
		return err
	} else {
		o.HtmlUrl = f.Link
		if o.Title == "" {
			o.Title = f.Title
		}
	}
	o.Text = ""

	return nil
}

func DeleteOldFeeds(c mpg.Context, w http.ResponseWriter, r *http.Request) {
	ctx := appengine.Timeout(c, time.Minute)
	gn := goon.FromContext(c)
	q := datastore.NewQuery(gn.Kind(&Feed{})).Filter("n=", timeMax).KeysOnly()
	if cur, err := datastore.DecodeCursor(r.FormValue("c")); err == nil {
		q = q.Start(cur)
	}
	it := q.Run(ctx)
	done := false
	var tasks []*taskqueue.Task
	for i := 0; i < 10000 && len(tasks) < 100; i++ {
		k, err := it.Next(nil)
		if err == datastore.Done {
			c.Criticalf("done")
			done = true
			break
		} else if err != nil {
			c.Errorf("err: %v", err)
			continue
		}
		values := make(url.Values)
		values.Add("f", k.StringID())
		tasks = append(tasks, taskqueue.NewPOSTTask("/tasks/delete-old-feed", values))
	}
	if len(tasks) > 0 {
		c.Errorf("deleting %v feeds", len(tasks))
		if _, err := taskqueue.AddMulti(c, tasks, ""); err != nil {
			c.Errorf("err: %v", err)
		}
	}
	if !done {
		if cur, err := it.Cursor(); err == nil {
			values := make(url.Values)
			values.Add("c", cur.String())
			taskqueue.Add(c, taskqueue.NewPOSTTask("/tasks/delete-old-feeds", values), "")
		} else {
			c.Errorf("err: %v", err)
		}
	}
}

func updateFeed(c mpg.Context, url string, feed *Feed, stories []*Story) error {
	gn := goon.FromContext(c)
	f := Feed{Url: url}
	if err := gn.Get(&f); err != nil {
		return errors.New(fmt.Sprintf("feed not found: %s", url))
	}

	// Compare the feed's listed update to the story's update.
	// Note: these may not be accurate, hence, only compare them to each other,
	// since they should have the same relative error.
	storyDate := f.Updated

	hasUpdated := !feed.Updated.IsZero()
	isFeedUpdated := f.Updated == feed.Updated
	if !hasUpdated {
		feed.Updated = f.Updated
	}
	feed.Date = f.Date
	f = *feed

	if hasUpdated && isFeedUpdated {
		c.Infof("feed %s already updated to %v, putting", url, feed.Updated)
		f.Updated = time.Now()
		if strings.TrimSpace(f.Url) == "" {
			c.Criticalf("badurl5: %v, %v", url, f)
			return errors.New("badurl5")
		}
		gn.PutComplete(&f)
		return nil
	}

	c.Debugf("hasUpdate: %v, isFeedUpdated: %v, storyDate: %v", hasUpdated, isFeedUpdated, storyDate)

	var newStories []*Story
	for _, s := range stories {
		if s.Updated.IsZero() || !s.Updated.Before(storyDate) {
			newStories = append(newStories, s)
		}
	}
	c.Debugf("%v possible stories to update", len(newStories))

	puts := []interface{}{&f}

	// find non existant stories
	fk := gn.Key(&f)
	getStories := make([]*Story, len(newStories))
	for i, s := range newStories {
		getStories[i] = &Story{Id: s.Id, Parent: fk}
	}
	err := gn.GetMulti(getStories)
	if _, ok := err.(appengine.MultiError); err != nil && !ok {
		c.Errorf("get multi error: %v", err.Error())
		return err
	}
	var updateStories []*Story
	for i, s := range getStories {
		if goon.NotFound(err, i) {
			updateStories = append(updateStories, newStories[i])
		} else if !newStories[i].Updated.IsZero() && !newStories[i].Updated.Equal(s.Updated) {
			newStories[i].Created = s.Created
			newStories[i].Published = s.Published
			updateStories = append(updateStories, newStories[i])
		}
	}
	c.Debugf("%v update stories", len(updateStories))

	for _, s := range updateStories {
		puts = append(puts, s)
		gn.Put(&StoryContent{
			Id:      1,
			Parent:  gn.Key(s),
			Content: s.content,
		})
	}

	c.Debugf("putting %v entities", len(puts))
	if len(puts) > 1 {
		f.Date = time.Now()
		if !hasUpdated {
			f.Updated = f.Date
		}
	}
	if f.Url == "" {
		c.Criticalf("badurl6: %v", f)
		return errors.New("badurl6")
	}
	gn.PutMultiComplete(puts)

	return nil
}