```
$ go run web-identity.go -cid 204367807228-ok7601k6gj1pgge7m09h7d79co8p35xx.apps.googleusercontent.com -csec XsT_PgPdT1nO9DD45rMLJw7G
2018/12/26 17:49:36 listening on http://localhost:8080/
```

> NOTE: for a reasonable test outcome, make sure the assumed user has at least permission/policy to list all buckets. That policy would look like below:

```
{
  "version": "2012-10-17",
  "statement": [
    {

	dst = append(dst, in...)
	return dst, err
}

// csvSplitSize is the size of each block.
// Blocks will read this much and find the first following newline.
// 128KB appears to be a very reasonable default.
const csvSplitSize = 128 << 10

// startReaders will read the header if needed and spin up a parser
// and a number of workers based on GOMAXPROCS.

//
// First, we read the chunk size but fail if it is larger
// than 16 MiB. We must not accept arbitrary large chunks.
// One 16 MiB is a reasonable max limit.
//
// Then we read the signature and payload data. We compute the SHA256 checksum
// of the payload and verify that it matches the expected signature value.
//

// is more efficient than decrypting ETags sequentually.
func DecryptETags(ctx context.Context, k kms.KMS, objects []ObjectInfo) error {
	const BatchSize = 250 // We process the objects in batches - 250 is a reasonable default.
	var (
		metadata = make([]map[string]string, 0, BatchSize)
		buckets  = make([]string, 0, BatchSize)
		names    = make([]string, 0, BatchSize)
	)
	for len(objects) > 0 {
		N := BatchSize

  - `HeadObject`
  - `GetObject`
  - `ListObjectsV2`
- If the ZIP file directory isn't located within the last 100MB the file will not be parsed.
- A maximum of 100M inside a single zip is allowed. However, a reasonable limit of 100,000 files inside a single ZIP archive is recommended for best performance and memory usage trade-off.

## Content-Type

ongoing basis, if such Contributor fails to notify You of the
non-compliance by some reasonable means prior to 60 days after You have
come back into compliance. Moreover, Your grants from a particular
Contributor are reinstated on an ongoing basis if such Contributor
notifies You of the non-compliance by some reasonable means, this is the
first time You have received notice of non-compliance with this License

// compacted until the limit is reached.
//
// This ensures that any branch will never contain an unreasonable amount of other branches,
// and also that small branches with few objects don't take up unreasonable amounts of space.
// This keeps the cache size at a reasonable size for all buckets.
//
// Whenever a branch is scanned, it is assumed that it will be un-compacted