func()

in shards/shards.go [366:443]

• 71 lines of code
• 11 McCabe index (conditional complexity)

func (ss *shardedSearcher) List(ctx context.Context, r query.Q) (rl *zoekt.RepoList, err error) {
	tr := trace.New("shardedSearcher.List", "")
	tr.LazyLog(r, true)
	metricListRunning.Inc()
	defer func() {
		metricListRunning.Dec()
		if rl != nil {
			tr.LazyPrintf("repos size: %d", len(rl.Repos))
			tr.LazyPrintf("crashes: %d", rl.Crashes)
		}
		if err != nil {
			tr.LazyPrintf("error: %v", err)
			tr.SetError()
		}
		tr.Finish()
	}()

	type res struct {
		rl  *zoekt.RepoList
		err error
	}

	if err := ss.rlock(ctx); err != nil {
		return nil, err
	}
	defer ss.runlock()
	tr.LazyPrintf("acquired lock")

	shards := ss.getShards()
	shardCount := len(shards)
	all := make(chan res, shardCount)
	tr.LazyPrintf("shardCount: %d", len(shards))

	for _, s := range shards {
		go func(s zoekt.Searcher) {
			metricListShardRunning.Inc()
			defer func() {
				metricListShardRunning.Dec()
				if r := recover(); r != nil {
					all <- res{
						&zoekt.RepoList{Crashes: 1}, nil,
					}
				}
			}()
			ms, err := s.List(ctx, r)
			all <- res{ms, err}
		}(s.Searcher)
	}

	crashes := 0
	uniq := map[string]*zoekt.RepoListEntry{}

	for i := 0; i < shardCount; i++ {
		r := <-all
		if r.err != nil {
			return nil, r.err
		}
		crashes += r.rl.Crashes
		for _, r := range r.rl.Repos {
			prev, ok := uniq[r.Repository.Name]
			if !ok {
				cp := *r
				uniq[r.Repository.Name] = &cp
			} else {
				prev.Stats.Add(&r.Stats)
			}
		}
	}

	aggregate := make([]*zoekt.RepoListEntry, 0, len(uniq))
	for _, v := range uniq {
		aggregate = append(aggregate, v)
	}
	return &zoekt.RepoList{
		Repos:   aggregate,
		Crashes: crashes,
	}, nil
}