Update code to fix almost all pre-existing lint errors

.errcheck-exclude

@@ -1,3 +1,5 @@
 io/ioutil.WriteFile
 io/ioutil.ReadFile
 (github.com/go-kit/kit/log.Logger).Log
+io.Copy
+(github.com/opentracing/opentracing-go.Tracer).Inject

Makefile

@@ -122,7 +122,7 @@ protos: $(PROTO_GOS)
 
 lint:
 	misspell -error docs
-	golangci-lint run --new-from-rev ed7c302fd968 --build-tags netgo --timeout=5m --enable golint --enable misspell --enable gofmt
+	golangci-lint run --build-tags netgo --timeout=5m --enable golint --enable misspell --enable gofmt
 
 	# Validate Kubernetes spec files. Requires:
 	# https://kubeval.instrumenta.dev

cmd/cortex/main_test.go

@@ -161,13 +161,13 @@ func captureOutput(t *testing.T) *capturedOutput {
 	co.wg.Add(1)
 	go func() {
 		defer co.wg.Done()
-		_, _ = io.Copy(&co.stdoutBuf, stdoutR)
+		io.Copy(&co.stdoutBuf, stdoutR)
 	}()
 
 	co.wg.Add(1)
 	go func() {
 		defer co.wg.Done()
-		_, _ = io.Copy(&co.stderrBuf, stderrR)
+		io.Copy(&co.stderrBuf, stderrR)
 	}()
 
 	return co

cmd/test-exporter/main.go

@@ -52,5 +52,6 @@ func main() {
 	}))
 
 	prometheus.MustRegister(runner)
-	server.Run()
+	err = server.Run()
+	util.CheckFatal("running server", err)
 }

pkg/alertmanager/alertmanager.go

@@ -78,6 +78,8 @@ func init() {
 			// from disk, we just ignore web-based reload signals. Config updates are
 			// only applied externally via ApplyConfig().
 			case <-webReload:
+			default:
+				continue
 			}
 		}
 	}()
@@ -176,7 +178,7 @@ func clusterWait(p *cluster.Peer, timeout time.Duration) func() time.Duration {
 
 // ApplyConfig applies a new configuration to an Alertmanager.
 func (am *Alertmanager) ApplyConfig(userID string, conf *config.Config) error {
-	templateFiles := make([]string, len(conf.Templates), len(conf.Templates))
+	templateFiles := make([]string, len(conf.Templates))
 	if len(conf.Templates) > 0 {
 		for i, t := range conf.Templates {
 			templateFiles[i] = filepath.Join(am.cfg.DataDir, "templates", userID, t)

pkg/chunk/aws/dynamodb_storage_client.go

@@ -245,7 +245,7 @@ func (a dynamoDBStorageClient) BatchWrite(ctx context.Context, input chunk.Write
 			if awsErr, ok := err.(awserr.Error); ok && ((awsErr.Code() == dynamodb.ErrCodeProvisionedThroughputExceededException) || request.Retryable()) {
 				logWriteRetry(ctx, requests)
 				unprocessed.TakeReqs(requests, -1)
-				a.writeThrottle.WaitN(ctx, len(requests))
+				_ = a.writeThrottle.WaitN(ctx, len(requests))
 				backoff.Wait()
 				continue
 			} else if ok && awsErr.Code() == validationException {
@@ -269,7 +269,7 @@ func (a dynamoDBStorageClient) BatchWrite(ctx context.Context, input chunk.Write
 		unprocessedItems := dynamoDBWriteBatch(resp.UnprocessedItems)
 		if len(unprocessedItems) > 0 {
 			logWriteRetry(ctx, unprocessedItems)
-			a.writeThrottle.WaitN(ctx, unprocessedItems.Len())
+			_ = a.writeThrottle.WaitN(ctx, unprocessedItems.Len())
 			unprocessed.TakeReqs(unprocessedItems, -1)
 		}
 

pkg/chunk/aws/dynamodb_storage_client_test.go

@@ -17,7 +17,8 @@ const (
 
 func TestChunksPartialError(t *testing.T) {
 	fixture := dynamoDBFixture(0, 10, 20)
-	defer fixture.Teardown()
+	defer testutils.TeardownFixture(t, fixture)
+
 	_, client, err := testutils.Setup(fixture, tableName)
 	require.NoError(t, err)
 

pkg/chunk/aws/dynamodb_table_client.go

@@ -80,7 +80,7 @@ func (d dynamoTableClient) backoffAndRetry(ctx context.Context, fn func(context.
 
 func (d callManager) backoffAndRetry(ctx context.Context, fn func(context.Context) error) error {
 	if d.limiter != nil { // Tests will have a nil limiter.
-		d.limiter.Wait(ctx)
+		_ = d.limiter.Wait(ctx)
 	}
 
 	backoff := util.NewBackoff(ctx, d.backoffConfig)

pkg/chunk/aws/mock.go

@@ -56,6 +56,7 @@ func (a dynamoDBStorageClient) setErrorParameters(provisionedErr, errAfter int)
 	}
 }
 
+//nolint:unused //Leaving this around in the case we need to create a table via mock this is useful.
 func (m *mockDynamoDBClient) createTable(name string) {
 	m.mtx.Lock()
 	defer m.mtx.Unlock()

pkg/chunk/cache/fifo_cache.go

@@ -228,7 +228,7 @@ func (c *FifoCache) Get(ctx context.Context, key string) (interface{}, bool) {
 	index, ok := c.index[key]
 	if ok {
 		updated := c.entries[index].updated
-		if c.validity == 0 || time.Now().Sub(updated) < c.validity {
+		if c.validity == 0 || time.Since(updated) < c.validity {
 			return c.entries[index].value, true
 		}
 

pkg/chunk/cache/fifo_cache_test.go

@@ -2,7 +2,6 @@ package cache
 
 import (
 	"context"
-	"fmt"
 	"strconv"
 	"testing"
 	"time"
@@ -88,10 +87,3 @@ func TestFifoCacheExpiry(t *testing.T) {
 	_, ok = c.Get(ctx, strconv.Itoa(0))
 	require.False(t, ok)
 }
-
-func (c *FifoCache) print() {
-	fmt.Println("first", c.first, "last", c.last)
-	for i, entry := range c.entries {
-		fmt.Printf("  %d -> key: %s, value: %v, next: %d, prev: %d\n", i, entry.key, entry.value, entry.next, entry.prev)
-	}
-}

pkg/chunk/cache/instrumented.go

@@ -75,7 +75,7 @@ func (i *instrumentedCache) Store(ctx context.Context, keys []string, bufs [][]b
 	}
 
 	method := i.name + ".store"
-	instr.CollectedRequest(ctx, method, requestDuration, instr.ErrorCode, func(ctx context.Context) error {
+	_ = instr.CollectedRequest(ctx, method, requestDuration, instr.ErrorCode, func(ctx context.Context) error {
 		sp := ot.SpanFromContext(ctx)
 		sp.LogFields(otlog.Int("keys", len(keys)))
 		i.Cache.Store(ctx, keys, bufs)
@@ -91,7 +91,7 @@ func (i *instrumentedCache) Fetch(ctx context.Context, keys []string) ([]string,
 		method  = i.name + ".fetch"
 	)
 
-	instr.CollectedRequest(ctx, method, requestDuration, instr.ErrorCode, func(ctx context.Context) error {
+	_ = instr.CollectedRequest(ctx, method, requestDuration, instr.ErrorCode, func(ctx context.Context) error {
 		sp := ot.SpanFromContext(ctx)
 		sp.LogFields(otlog.Int("keys requested", len(keys)))
 

pkg/chunk/cache/memcached.go

@@ -36,7 +36,7 @@ type observableVecCollector struct {
 func (observableVecCollector) Register()                             {}
 func (observableVecCollector) Before(method string, start time.Time) {}
 func (o observableVecCollector) After(method, statusCode string, start time.Time) {
-	o.v.WithLabelValues(method, statusCode).Observe(time.Now().Sub(start).Seconds())
+	o.v.WithLabelValues(method, statusCode).Observe(time.Since(start).Seconds())
 }
 
 // MemcachedConfig is config to make a Memcached
@@ -135,7 +135,7 @@ func memcacheStatusCode(err error) string {
 
 // Fetch gets keys from the cache. The keys that are found must be in the order of the keys requested.
 func (c *Memcached) Fetch(ctx context.Context, keys []string) (found []string, bufs [][]byte, missed []string) {
-	instr.CollectedRequest(ctx, "Memcache.Get", c.requestDuration, memcacheStatusCode, func(ctx context.Context) error {
+	_ = instr.CollectedRequest(ctx, "Memcache.Get", c.requestDuration, memcacheStatusCode, func(ctx context.Context) error {
 		if c.cfg.BatchSize == 0 {
 			found, bufs, missed = c.fetch(ctx, keys)
 			return nil
@@ -149,7 +149,7 @@ func (c *Memcached) Fetch(ctx context.Context, keys []string) (found []string, b
 
 func (c *Memcached) fetch(ctx context.Context, keys []string) (found []string, bufs [][]byte, missed []string) {
 	var items map[string]*memcache.Item
-	instr.CollectedRequest(ctx, "Memcache.GetMulti", c.requestDuration, memcacheStatusCode, func(_ context.Context) error {
+	err := instr.CollectedRequest(ctx, "Memcache.GetMulti", c.requestDuration, memcacheStatusCode, func(_ context.Context) error {
 		sp := opentracing.SpanFromContext(ctx)
 		sp.LogFields(otlog.Int("keys requested", len(keys)))
 
@@ -166,6 +166,10 @@ func (c *Memcached) fetch(ctx context.Context, keys []string) (found []string, b
 		return err
 	})
 
+	if err != nil {
+		return found, bufs, keys
+	}
+
 	for _, key := range keys {
 		item, ok := items[key]
 		if ok {
@@ -248,7 +252,7 @@ func (c *Memcached) Stop() {
 // HashKey hashes key into something you can store in memcached.
 func HashKey(key string) string {
 	hasher := fnv.New64a()
-	hasher.Write([]byte(key)) // This'll never error.
+	_, _ = hasher.Write([]byte(key)) // This'll never error.
 
 	// Hex because memcache errors for the bytes produced by the hash.
 	return hex.EncodeToString(hasher.Sum(nil))

pkg/chunk/cache/redis_cache_test.go

@@ -19,9 +19,9 @@ func TestRedisCache(t *testing.T) {
 
 	conn := redigomock.NewConn()
 	conn.Clear()
-	pool := redis.NewPool(func() (redis.Conn, error) {
+	pool := &redis.Pool{Dial: func() (redis.Conn, error) {
 		return conn, nil
-	}, 10)
+	}, MaxIdle: 10}
 
 	keys := []string{"key1", "key2", "key3"}
 	bufs := [][]byte{[]byte("data1"), []byte("data2"), []byte("data3")}

pkg/chunk/cassandra/storage_client.go

@@ -294,7 +294,6 @@ func (s *StorageClient) query(ctx context.Context, query chunk.IndexQuery, callb
 
 // readBatch represents a batch of rows read from Cassandra.
 type readBatch struct {
-	consumed   bool
 	rangeValue []byte
 	value      []byte
 }

pkg/chunk/chunk_store.go

@@ -118,14 +118,17 @@ func (c *store) Put(ctx context.Context, chunks []Chunk) error {
 
 // PutOne implements ChunkStore
 func (c *store) PutOne(ctx context.Context, from, through model.Time, chunk Chunk) error {
+	log, ctx := spanlogger.New(ctx, "ChunkStore.PutOne")
 	chunks := []Chunk{chunk}
 
 	err := c.storage.PutChunks(ctx, chunks)
 	if err != nil {
 		return err
 	}
 
-	c.writeBackCache(ctx, chunks)
+	if cacheErr := c.writeBackCache(ctx, chunks); cacheErr != nil {
+		level.Warn(log).Log("msg", "could not store chunks in chunk cache", "err", cacheErr)
+	}
 
 	writeReqs, err := c.calculateIndexEntries(chunk.UserID, from, through, chunk)
 	if err != nil {
@@ -252,6 +255,7 @@ func (c *store) LabelNamesForMetricName(ctx context.Context, userID string, from
 }
 
 func (c *store) validateQueryTimeRange(ctx context.Context, userID string, from *model.Time, through *model.Time) (bool, error) {
+	//nolint:ineffassign,staticcheck //Leaving ctx even though we don't currently use it, we want to make it available for when we might need it and hopefully will ensure us using the correct context at that time
 	log, ctx := spanlogger.New(ctx, "store.validateQueryTimeRange")
 	defer log.Span.Finish()
 

pkg/chunk/chunk_store_test.go

@@ -711,7 +711,8 @@ func BenchmarkIndexCaching(b *testing.B) {
 	b.ResetTimer()
 
 	for i := 0; i < b.N; i++ {
-		store.Put(ctx, []Chunk{fooChunk1})
+		err := store.Put(ctx, []Chunk{fooChunk1})
+		require.NoError(b, err)
 	}
 }
 
@@ -813,7 +814,7 @@ func TestStoreMaxLookBack(t *testing.T) {
 	chunks, err = storeWithLookBackLimit.Get(ctx, userID, now.Add(-time.Hour), now, matchers...)
 	require.NoError(t, err)
 	require.Equal(t, 1, len(chunks))
-	chunks[0].Through.Equal(now)
+	require.Equal(t, now, chunks[0].Through)
 }
 
 func benchmarkParseIndexEntries(i int64, b *testing.B) {

pkg/chunk/chunk_test.go

@@ -268,7 +268,8 @@ func BenchmarkEncode(b *testing.B) {
 
 	for i := 0; i < b.N; i++ {
 		chunk.encoded = nil
-		chunk.Encode()
+		err := chunk.Encode()
+		require.NoError(b, err)
 	}
 }
 

pkg/chunk/composite_store_test.go

@@ -6,6 +6,8 @@ import (
 	"reflect"
 	"testing"
 
+	"github.com/stretchr/testify/require"
+
 	"github.com/prometheus/common/model"
 	"github.com/prometheus/prometheus/pkg/labels"
 	"github.com/weaveworks/common/test"
@@ -180,7 +182,8 @@ func TestCompositeStore(t *testing.T) {
 	} {
 		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
 			have := []result{}
-			tc.cs.forStores(model.TimeFromUnix(tc.from), model.TimeFromUnix(tc.through), collect(&have))
+			err := tc.cs.forStores(model.TimeFromUnix(tc.from), model.TimeFromUnix(tc.through), collect(&have))
+			require.NoError(t, err)
 			if !reflect.DeepEqual(tc.want, have) {
 				t.Fatalf("wrong stores - %s", test.Diff(tc.want, have))
 			}
@@ -231,16 +234,12 @@ func TestCompositeStoreLabels(t *testing.T) {
 	} {
 		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
 			have, err := cs.LabelNamesForMetricName(context.Background(), "", model.TimeFromUnix(tc.from), model.TimeFromUnix(tc.through), "")
-			if err != nil {
-				t.Fatalf("err - %s", err)
-			}
+			require.NoError(t, err)
 			if !reflect.DeepEqual(tc.want, have) {
 				t.Fatalf("wrong label names - %s", test.Diff(tc.want, have))
 			}
 			have, err = cs.LabelValuesForMetricName(context.Background(), "", model.TimeFromUnix(tc.from), model.TimeFromUnix(tc.through), "", "")
-			if err != nil {
-				t.Fatalf("err - %s", err)
-			}
+			require.NoError(t, err)
 			if !reflect.DeepEqual(tc.want, have) {
 				t.Fatalf("wrong label values - %s", test.Diff(tc.want, have))
 			}

pkg/chunk/encoding/bigchunk_test.go

@@ -84,7 +84,7 @@ func BenchmarkBiggerChunkMemory(b *testing.B) {
 // printSize calculates various sizes of the chunk when encoded, and in memory.
 func (b *bigchunk) printSize() {
 	var buf bytes.Buffer
-	b.Marshal(&buf)
+	_ = b.Marshal(&buf)
 
 	var size, allocd int
 	for _, c := range b.chunks {

pkg/chunk/encoding/chunk_test.go

@@ -117,6 +117,8 @@ func testChunkEncoding(t *testing.T, encoding Encoding, samples int) {
 
 	bs1 := buf.Bytes()
 	chunk, err = NewForEncoding(encoding)
+	require.NoError(t, err)
+
 	err = chunk.UnmarshalFromBuf(bs1)
 	require.NoError(t, err)
 

pkg/chunk/encoding/varbit.go

@@ -13,7 +13,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-
+//nolint //Since this was copied from Prometheus leave it as is
 package encoding
 
 import (

pkg/chunk/encoding/varbit_helpers.go

@@ -13,7 +13,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-
+//nolint //Since this was copied from Prometheus leave it as is
 package encoding
 
 import "github.com/prometheus/common/model"

pkg/chunk/gcp/bigtable_index_client.go

@@ -60,8 +60,6 @@ type storageClientColumnKey struct {
 	schemaCfg chunk.SchemaConfig
 	client    *bigtable.Client
 	keysFn    keysFn
-
-	distributeKeys bool
 }
 
 // storageClientV1 implements chunk.storageClient for GCP.

pkg/chunk/schema_config.go

@@ -320,12 +320,6 @@ func (cfg *SchemaConfig) Load() error {
 	return cfg.Validate()
 }
 
-// PrintYaml dumps the yaml to stdout, to aid in migration
-func (cfg SchemaConfig) PrintYaml() {
-	encoder := yaml.NewEncoder(os.Stdout)
-	encoder.Encode(cfg)
-}
-
 // Bucket describes a range of time with a tableName and hashKey
 type Bucket struct {
 	from       uint32