apollo-backend/internal/worker/subreddits.go
André Medeiros 9341e08123 feat(ops): add distributed tracing (#109)
* tracing

* instrument redis

* add instrumentation around queue acks

* adjust backoff schedules for reddit

* set proper http client on reddit

* populate account last message ID on upsert

* pass last message id on upsert

* schedule accounts in a predictable order
2022-11-05 15:59:33 -04:00

476 lines
12 KiB
Go

package worker
import (
"context"
"fmt"
"math/rand"
"os"
"strconv"
"strings"
"time"
"github.com/DataDog/datadog-go/statsd"
"github.com/adjust/rmq/v5"
"github.com/go-redis/redis/v8"
"github.com/jackc/pgx/v4/pgxpool"
"github.com/sideshow/apns2"
"github.com/sideshow/apns2/payload"
"github.com/sideshow/apns2/token"
"go.opentelemetry.io/otel/trace"
"go.uber.org/zap"
"github.com/christianselig/apollo-backend/internal/domain"
"github.com/christianselig/apollo-backend/internal/reddit"
"github.com/christianselig/apollo-backend/internal/repository"
)
type subredditsWorker struct {
context.Context
logger *zap.Logger
tracer trace.Tracer
statsd *statsd.Client
db *pgxpool.Pool
redis *redis.Client
queue rmq.Connection
reddit *reddit.Client
apns *token.Token
consumers int
accountRepo domain.AccountRepository
deviceRepo domain.DeviceRepository
subredditRepo domain.SubredditRepository
watcherRepo domain.WatcherRepository
}
const (
subredditNotificationTitleFormat = "📣 \u201c%s\u201d Watcher"
subredditNotificationBodyFormat = "r/%s: \u201c%s\u201d"
)
func NewSubredditsWorker(ctx context.Context, logger *zap.Logger, tracer trace.Tracer, statsd *statsd.Client, db *pgxpool.Pool, redis *redis.Client, queue rmq.Connection, consumers int) Worker {
reddit := reddit.NewClient(
os.Getenv("REDDIT_CLIENT_ID"),
os.Getenv("REDDIT_CLIENT_SECRET"),
tracer,
statsd,
redis,
consumers,
)
var apns *token.Token
{
authKey, err := token.AuthKeyFromFile(os.Getenv("APPLE_KEY_PATH"))
if err != nil {
panic(err)
}
apns = &token.Token{
AuthKey: authKey,
KeyID: os.Getenv("APPLE_KEY_ID"),
TeamID: os.Getenv("APPLE_TEAM_ID"),
}
}
return &subredditsWorker{
ctx,
logger,
tracer,
statsd,
db,
redis,
queue,
reddit,
apns,
consumers,
repository.NewPostgresAccount(db),
repository.NewPostgresDevice(db),
repository.NewPostgresSubreddit(db),
repository.NewPostgresWatcher(db),
}
}
func (sw *subredditsWorker) Start() error {
queue, err := sw.queue.OpenQueue("subreddits")
if err != nil {
return err
}
sw.logger.Info("starting up subreddits worker", zap.Int("consumers", sw.consumers))
prefetchLimit := int64(sw.consumers * 2)
if err := queue.StartConsuming(prefetchLimit, pollDuration); err != nil {
return err
}
host, _ := os.Hostname()
for i := 0; i < sw.consumers; i++ {
name := fmt.Sprintf("consumer %s-%d", host, i)
consumer := NewSubredditsConsumer(sw, i)
if _, err := queue.AddConsumer(name, consumer); err != nil {
return err
}
}
return nil
}
func (sw *subredditsWorker) Stop() {
<-sw.queue.StopAllConsuming() // wait for all Consume() calls to finish
}
type subredditsConsumer struct {
*subredditsWorker
tag int
apnsSandbox *apns2.Client
apnsProduction *apns2.Client
}
func NewSubredditsConsumer(sw *subredditsWorker, tag int) *subredditsConsumer {
return &subredditsConsumer{
sw,
tag,
apns2.NewTokenClient(sw.apns),
apns2.NewTokenClient(sw.apns).Production(),
}
}
func (sc *subredditsConsumer) Consume(delivery rmq.Delivery) {
ctx, cancel := context.WithCancel(sc)
defer cancel()
id, err := strconv.ParseInt(delivery.Payload(), 10, 64)
if err != nil {
sc.logger.Error("failed to parse subreddit id from payload", zap.Error(err), zap.String("payload", delivery.Payload()))
_ = delivery.Reject()
return
}
sc.logger.Debug("starting job", zap.Int64("subreddit#id", id))
defer func() { _ = delivery.Ack() }()
subreddit, err := sc.subredditRepo.GetByID(ctx, id)
if err != nil {
sc.logger.Error("failed to fetch subreddit from database", zap.Error(err), zap.Int64("subreddit#id", id))
return
}
watchers, err := sc.watcherRepo.GetBySubredditID(ctx, subreddit.ID)
if err != nil {
sc.logger.Error("failed to fetch watchers from database",
zap.Error(err),
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
)
return
}
if len(watchers) == 0 {
sc.logger.Debug("no watchers for subreddit, bailing early",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
)
return
}
threshold := time.Now().Add(-24 * time.Hour)
posts := []*reddit.Thing{}
before := ""
finished := false
seenPosts := map[string]bool{}
// Load 500 newest posts
sc.logger.Debug("loading up to 500 new posts",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
)
for page := 0; page < 5; page++ {
sc.logger.Debug("loading new posts",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.Int("page", page),
)
i := rand.Intn(len(watchers))
watcher := watchers[i]
rac := sc.reddit.NewAuthenticatedClient(watcher.Account.AccountID, watcher.Account.RefreshToken, watcher.Account.AccessToken)
sps, err := rac.SubredditNew(ctx,
subreddit.Name,
reddit.WithQuery("before", before),
reddit.WithQuery("limit", "100"),
reddit.WithQuery("show", "all"),
reddit.WithQuery("always_show_media", "1"),
)
if err != nil {
sc.logger.Error("failed to fetch new posts",
zap.Error(err),
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.Int("page", page),
)
continue
}
sc.logger.Debug("loaded new posts",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.Int("page", page),
zap.Int("count", sps.Count),
)
// If it's empty, we're done
if sps.Count == 0 {
break
}
// If we don't have 100 posts, we're going to be done
if sps.Count < 100 {
finished = true
}
for _, post := range sps.Children {
if post.CreatedAt.Before(threshold) {
finished = true
break
}
if _, ok := seenPosts[post.ID]; !ok {
posts = append(posts, post)
seenPosts[post.ID] = true
}
}
if finished {
sc.logger.Debug("reached date threshold",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.Int("page", page),
)
break
}
}
// Load hot posts
sc.logger.Debug("loading hot posts",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
)
{
i := rand.Intn(len(watchers))
watcher := watchers[i]
rac := sc.reddit.NewAuthenticatedClient(watcher.Account.AccountID, watcher.Account.RefreshToken, watcher.Account.AccessToken)
sps, err := rac.SubredditHot(ctx,
subreddit.Name,
reddit.WithQuery("limit", "100"),
reddit.WithQuery("show", "all"),
reddit.WithQuery("always_show_media", "1"),
)
if err != nil {
sc.logger.Error("failed to fetch hot posts",
zap.Error(err),
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
)
} else {
sc.logger.Debug("loaded hot posts",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.Int("count", sps.Count),
)
for _, post := range sps.Children {
if post.CreatedAt.Before(threshold) {
break
}
if _, ok := seenPosts[post.ID]; !ok {
posts = append(posts, post)
seenPosts[post.ID] = true
}
}
}
}
sc.logger.Debug("checking posts for watcher hits",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.Int("count", len(posts)),
)
for _, post := range posts {
lowcaseAuthor := strings.ToLower(post.Author)
lowcaseTitle := strings.ToLower(post.Title)
lowcaseFlair := strings.ToLower(post.Flair)
lowcaseDomain := strings.ToLower(post.URL)
notifs := []domain.Watcher{}
for _, watcher := range watchers {
// Make sure we only alert on posts created after the search
if watcher.CreatedAt.After(post.CreatedAt) {
continue
}
matched := watcher.KeywordMatches(lowcaseTitle)
if watcher.Author != "" && lowcaseAuthor != watcher.Author {
matched = false
}
if watcher.Upvotes > 0 && post.Score < watcher.Upvotes {
matched = false
}
if watcher.Flair != "" && !strings.Contains(lowcaseFlair, watcher.Flair) {
matched = false
}
if watcher.Domain != "" && !strings.Contains(lowcaseDomain, watcher.Domain) {
matched = false
}
if !matched {
continue
}
sc.logger.Debug("matched post",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.Int64("watcher#id", watcher.ID),
zap.String("watcher#keywords", watcher.Keyword),
zap.Int64("watcher#upvotes", watcher.Upvotes),
zap.String("post#id", post.ID),
zap.String("post#title", post.Title),
zap.Int64("post#score", post.Score),
)
lockKey := fmt.Sprintf("watcher:%d:%s", watcher.DeviceID, post.ID)
notified, _ := sc.redis.Get(ctx, lockKey).Bool()
if notified {
sc.logger.Debug("already notified, skipping",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.Int64("watcher#id", watcher.ID),
zap.String("post#id", post.ID),
)
continue
}
if err := sc.watcherRepo.IncrementHits(ctx, watcher.ID); err != nil {
sc.logger.Error("could not increment hits",
zap.Error(err),
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.Int64("watcher#id", watcher.ID),
)
return
}
sc.logger.Debug("got a hit",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.Int64("watcher#id", watcher.ID),
zap.String("post#id", post.ID),
)
sc.redis.SetEX(ctx, lockKey, true, 24*time.Hour)
notifs = append(notifs, watcher)
}
if len(notifs) == 0 {
continue
}
sc.logger.Debug("got hits for post",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.String("post#id", post.ID),
zap.Int("count", len(notifs)),
)
payload := payloadFromPost(post)
for _, watcher := range notifs {
title := fmt.Sprintf(subredditNotificationTitleFormat, watcher.Label)
payload.AlertTitle(title)
body := fmt.Sprintf(subredditNotificationBodyFormat, subreddit.Name, post.Title)
payload.AlertBody(body)
notification := &apns2.Notification{}
notification.Topic = "com.christianselig.Apollo"
notification.DeviceToken = watcher.Device.APNSToken
notification.Payload = payload
client := sc.apnsProduction
if watcher.Device.Sandbox {
client = sc.apnsSandbox
}
res, err := client.Push(notification)
if err != nil {
_ = sc.statsd.Incr("apns.notification.errors", []string{}, 1)
sc.logger.Error("failed to send notification",
zap.Error(err),
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.String("post#id", post.ID),
zap.String("apns", watcher.Device.APNSToken),
)
} else if !res.Sent() {
_ = sc.statsd.Incr("apns.notification.errors", []string{}, 1)
sc.logger.Error("notificaion not sent",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.String("post#id", post.ID),
zap.String("apns", watcher.Device.APNSToken),
zap.Int("response#status", res.StatusCode),
zap.String("response#reason", res.Reason),
)
} else {
_ = sc.statsd.Incr("apns.notification.sent", []string{}, 1)
sc.logger.Info("sent notification",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
zap.String("post#id", post.ID),
zap.String("device#token", watcher.Device.APNSToken),
)
}
}
}
sc.logger.Debug("finishing job",
zap.Int64("subreddit#id", id),
zap.String("subreddit#name", subreddit.NormalizedName()),
)
}
func payloadFromPost(post *reddit.Thing) *payload.Payload {
payload := payload.
NewPayload().
AlertSummaryArg(post.Subreddit).
Category("subreddit-watcher").
Custom("post_title", post.Title).
Custom("post_id", post.ID).
Custom("subreddit", post.Subreddit).
Custom("author", post.Author).
Custom("post_age", post.CreatedAt).
ThreadID("subreddit-watcher").
MutableContent().
Sound("traloop.wav")
if post.Thumbnail != "" && !post.Over18 {
payload.Custom("thumbnail", post.Thumbnail)
}
return payload
}