Add go.mod and setup Go module

Note that AWS SDK for Go (v1) version 1.21.6 is where CloudWatch Logs
added the LogGroupNames field to clouwatchlogs.StartQueryInput.
Previously you could only query one log group at a time.

See:

- aws/aws-sdk-go#2718
- https://github.com/aws/aws-sdk-go/releases/tag/v1.21.6

As of this checkpoint, `$ go test` is passing on go1.16.4 windows/amd64
and go go1.15.12 linux/amd64 but I haven't tested either on Go 1.13
(the expected minimum required version) or on MacOS.

go.mod

@@ -0,0 +1,9 @@
+module github.com/gogama/incite
+
+go 1.13
+
+require (
+	github.com/aws/aws-sdk-go v1.21.6
+	github.com/stretchr/testify v1.7.0
+	golang.org/x/net v0.0.0-20210614182718-04defd469f4e // indirect
+)

go.sum

@@ -0,0 +1,24 @@
+github.com/aws/aws-sdk-go v1.21.6 h1:3GuIm55Uls52aQIDGBnSEZbk073jpasfQyeM5eZU61Q=
+github.com/aws/aws-sdk-go v1.21.6/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpiN924inxo=
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af h1:pmfjZENx5imkbgOkpRUYLnmbU7UEFbjtDA2hxJ1ichM=
+github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af/go.mod h1:Nht3zPeWKUH0NzdCt2Blrr5ys8VGpn0CEB0cQHVjt7k=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0 h1:4G4v2dO3VZwixGIRoQ5Lfboy6nUhCyYzaqnIAPPhYs4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+golang.org/x/net v0.0.0-20210614182718-04defd469f4e h1:XpT3nA5TvE525Ne3hInMh6+GETgn27Zfm9dxsThnX2Q=
+golang.org/x/net v0.0.0-20210614182718-04defd469f4e/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/text v0.3.6 h1:aRYxNxv6iGQlyVaZmk6ZgYEDa+Jg18DxebPSrd6bg1M=
+golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

incite.go

@@ -554,22 +554,17 @@ func (m *mgr) startNextChunk() error { // Assert: Lock is acquired.
 }
 
 func isTemporary(err error) bool {
-	switch x := err.(type) {
-	case *cloudwatchlogs.DataAlreadyAcceptedException, *cloudwatchlogs.InvalidOperationException,
-		*cloudwatchlogs.InvalidParameterException, *cloudwatchlogs.InvalidSequenceTokenException,
-		*cloudwatchlogs.MalformedQueryException, *cloudwatchlogs.OperationAbortedException,
-		*cloudwatchlogs.ResourceAlreadyExistsException, *cloudwatchlogs.ResourceNotFoundException,
-		*cloudwatchlogs.UnrecognizedClientException:
-		return false
-	case *cloudwatchlogs.LimitExceededException, *cloudwatchlogs.ServiceUnavailableException:
-		return true
-	case awserr.RequestFailure:
-		// Omit 'e' suffix on 'throttl' to match Throttled and Throttling.
-		return strings.Contains(strings.ToLower(x.Code()), "throttl") ||
-			strings.Contains(strings.ToLower(x.Message()), "rate exceeded")
-	default:
-		return false
+	if x, ok := err.(awserr.RequestFailure); ok {
+		switch x.Code() {
+		case cloudwatchlogs.ErrCodeLimitExceededException, cloudwatchlogs.ErrCodeServiceUnavailableException:
+			return true
+		default:
+			// Omit 'e' suffix on 'throttl' to match Throttled and Throttling.
+			return strings.Contains(strings.ToLower(x.Code()), "throttl") ||
+				strings.Contains(strings.ToLower(x.Message()), "rate exceeded")
+		}
 	}
+	return false
 }
 
 func (m *mgr) pollNextChunk() int {