Amazon S3

Create buckets and store, retrieve, copy and delete object bytes.

Plan: Free111 of 116 operations implemented3Known differences

Basic object reads work; range reads and reads of a specified older version failed in testing of Vera 1.2.0 preview.

Example checked on Vera 1.2.2, 8 November 2026. Each coverage note names its own evidence and date.

Connect

This Free service needs no license key. Start Vera as in Get started, then run this in a terminal of its own, from an empty scratch directory. It gives the official AWS CLI dummy credentials and a config file of its own, so no AWS account is needed and your own AWS profile isn't touched.

export VERA_ENDPOINT="http://localhost:5003"
export AWS_ACCESS_KEY_ID=test AWS_SECRET_ACCESS_KEY=test
export AWS_REGION=us-east-1 AWS_DEFAULT_REGION=us-east-1
export AWS_SHARED_CREDENTIALS_FILE=/dev/null
export AWS_EC2_METADATA_DISABLED=true
export AWS_PAGER="" AWS_CLI_AUTO_PROMPT=off
unset AWS_PROFILE AWS_DEFAULT_PROFILE
unset AWS_SESSION_TOKEN AWS_SECURITY_TOKEN
unset AWS_WEB_IDENTITY_TOKEN_FILE AWS_ROLE_ARN AWS_ROLE_SESSION_NAME
unset AWS_CONTAINER_CREDENTIALS_FULL_URI
unset AWS_CONTAINER_CREDENTIALS_RELATIVE_URI
cat > vera-aws-config <<'EOF'
[default]
region = us-east-1
output = json
cli_binary_format = base64
s3 =
    addressing_style = path
EOF
export AWS_CONFIG_FILE="$PWD/vera-aws-config"

When you've finished every example in this terminal, close it and delete vera-aws-config, not before.

The example uses the AWS CLI’s s3api commands. The emulator serves the 2006-03-01 API over the REST XML protocol, and the example was checked with the official AWS CLI 2.31.35. The higher-level aws s3 commands weren’t tested.

The config file turns on path-style addressing, so a bucket and its objects are paths on VERA_ENDPOINT: hello.txt in vera-docs-storage is $VERA_ENDPOINT/vera-docs-storage/hello.txt. In earlier testing, an unsigned GET of that URL returned the object’s bytes.

Example

Create a bucket, upload a small file to it and download it again.

printf 'Vera documentation object\n' > payload.txt
aws --endpoint-url "$VERA_ENDPOINT" s3api create-bucket --bucket vera-docs-storage
aws --endpoint-url "$VERA_ENDPOINT" s3api put-object \
  --bucket vera-docs-storage --key hello.txt --body payload.txt
aws --endpoint-url "$VERA_ENDPOINT" s3api get-object \
  --bucket vera-docs-storage --key hello.txt download.txt

The download writes the object to download.txt and prints its metadata, including these fields. Time fields differ on every run.

{
    "ContentLength": 26,
    "ETag": "\"37d345de60cd441214979010cfd6717c\"",
    "ChecksumCRC64NVME": "nIS13osbxSA=",
    "ChecksumType": "FULL_OBJECT",
    "ContentType": "binary/octet-stream",
    "ServerSideEncryption": "AES256"
}

ServerSideEncryption is a returned field: it doesn’t show that the object is encrypted at rest.

Compare the download with the original using cmp, then read the object’s metadata again:

cmp payload.txt download.txt
aws --endpoint-url "$VERA_ENDPOINT" s3api head-object --bucket vera-docs-storage --key hello.txt

cmp prints nothing and exits with status 0: the downloaded file is byte for byte the same 26 bytes as payload.txt. The head-object output has the same ContentLength, ETag, ContentType and ServerSideEncryption as the download.

To clean up, delete the object and the bucket, then the two local files:

aws --endpoint-url "$VERA_ENDPOINT" s3api delete-object --bucket vera-docs-storage --key hello.txt
aws --endpoint-url "$VERA_ENDPOINT" s3api delete-bucket --bucket vera-docs-storage
rm payload.txt download.txt

Supported features

Buckets, created, checked with HeadBucket and deleted. In earlier testing, HeadBucket returned 404 once a bucket was deleted.
Objects, uploaded with PutObject, downloaded byte for byte with GetObject, inspected with HeadObject and deleted, with an ETag and a CRC64NVME checksum.
Copies: CopyObject made a byte-for-byte copy of an object.
Multipart uploads, with a single part: an upload was created, its one part uploaded and the upload completed, and the object read back. See Limitations for what wasn’t tested.
Versioning settings and version lists: a bucket’s versioning setting is recorded, and two puts of the same key in a versioned bucket gave two version IDs, both listed by ListObjectVersions. Reading an older version failed: see Limitations.
Objects from other services: Data Firehose writes the records it delivers to buckets in the emulator.
Object listing, in other services’ examples: ListObjectsV2 showed that the DataSync example’s destination bucket stayed empty, and found an object delivered in a Data Firehose diagnostic. Pagination and other listing variants weren’t checked.
Also served, not yet tested: batch deletes, bucket settings such as CORS, encryption, lifecycle, logging, notifications, policies, replication, tagging and websites, object tags, ACLs, legal holds and retention, restores and SelectObjectContent.

Limitations

The main limits are below. A few more apply to every service, and the API coverage notes cover smaller differences.

Range reads returned the whole object. In Vera 1.2.0 preview, a standard SDK and the official AWS CLI asked for Range: bytes=0-4 of an 11-byte object holding hello-world. Both got the whole 11 bytes with HTTP 200, though the response had AcceptRanges: bytes. Range reads weren’t checked again on Vera 1.2.0-rc.3.
Older versions couldn’t be read. In a versioned bucket in Vera 1.2.0 preview, two puts of the same key gave two version IDs, and ListObjectVersions listed both. An ordinary get returned the latest body, two, but a get with the first put’s VersionId returned 404 NoSuchKey. Listing versions doesn’t mean you can read them.
Only a small multipart upload was tested. One 14-byte part was uploaded and completed. Large parts, uploads of several parts, conditional requests, concurrent uploads and multipart failure handling weren’t verified.
Encryption wasn’t tested. Objects come back with ServerSideEncryption set to AES256, but that doesn’t show they’re encrypted at rest.
Higher-level commands and bucket automation weren’t tested. The aws s3 commands, lifecycle rules running, event notifications being delivered, replication and access policy enforcement weren’t verified. Directory buckets and S3 Express sessions weren’t tested either.
S3 Select and torrents may be synthetic. Earlier source inspection, not a run of a release build, found that S3 Select returns stored data without evaluating SQL, and that torrent responses are synthetic and don’t describe the object.

API coverage

Every operation in AWS's published 2006-03-01 API (SDK model, botocore 1.43.105), and whether the emulator implements it. Availability combines the earlier implementation inventory with the dated observations below; checking a page's example does not verify every operation. Each note names its evidence first; an observation given without a build or date comes from earlier testing, on 3 November 2026. What the statuses mean

Operation	Status	Notes
AbortMultipartUpload	Implemented
CompleteMultipartUpload	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — a single 14-byte part was uploaded, the upload completed and the object read back. Large parts, several parts, concurrency and failure handling weren't checked.
CopyObject	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — made a byte-for-byte copy of an object.
CreateBucket	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — created a bucket used with path-style addressing.
CreateBucketMetadataConfiguration	Implemented
CreateBucketMetadataTableConfiguration	Implemented
CreateMultipartUpload	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — a single 14-byte part was uploaded, the upload completed and the object read back. Large parts, several parts, concurrency and failure handling weren't checked.
CreateSession	Implemented
DeleteBucket	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — deleted an empty bucket.
DeleteBucketAnalyticsConfiguration	Implemented
DeleteBucketCors	Implemented
DeleteBucketEncryption	Implemented
DeleteBucketIntelligentTieringConfiguration	Implemented
DeleteBucketInventoryConfiguration	Implemented
DeleteBucketLifecycle	Implemented
DeleteBucketMetadataConfiguration	Implemented
DeleteBucketMetadataTableConfiguration	Implemented
DeleteBucketMetricsConfiguration	Implemented
DeleteBucketOwnershipControls	Implemented
DeleteBucketPolicy	Implemented
DeleteBucketReplication	Implemented
DeleteBucketTagging	Implemented
DeleteBucketWebsite	Implemented
DeleteObject	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — deleted the example object.
DeleteObjectAnnotation	Not implemented
DeleteObjectTagging	Implemented
DeleteObjects	Implemented
DeletePublicAccessBlock	Implemented
GetBucketAbac	Implemented
GetBucketAccelerateConfiguration	Implemented
GetBucketAcl	Implemented
GetBucketAnalyticsConfiguration	Implemented
GetBucketCors	Implemented
GetBucketEncryption	Implemented
GetBucketIntelligentTieringConfiguration	Implemented
GetBucketInventoryConfiguration	Implemented
GetBucketLifecycle	Implemented
GetBucketLifecycleConfiguration	Implemented
GetBucketLocation	Implemented
GetBucketLogging	Implemented
GetBucketMetadataConfiguration	Implemented
GetBucketMetadataTableConfiguration	Implemented
GetBucketMetricsConfiguration	Implemented
GetBucketNotification	Implemented
GetBucketNotificationConfiguration	Implemented
GetBucketOwnershipControls	Implemented
GetBucketPolicy	Implemented
GetBucketPolicyStatus	Implemented
GetBucketReplication	Implemented
GetBucketRequestPayment	Implemented
GetBucketTagging	Implemented
GetBucketVersioning	Implemented
GetBucketWebsite	Implemented
GetObject	Known difference	Local observation: Vera 1.2.0 preview, 5 November 2026 — returned a 26-byte object byte for byte. A request with `Range: bytes=0-4` for an 11-byte object returned the whole object with HTTP `200`, though the response has `AcceptRanges: bytes`. In a versioned bucket, a get with the first version's `VersionId` returned `404 NoSuchKey`, while an ordinary get returned the latest body.
GetObjectAcl	Implemented
GetObjectAnnotation	Not implemented
GetObjectAttributes	Implemented
GetObjectLegalHold	Implemented
GetObjectLockConfiguration	Implemented
GetObjectRetention	Implemented
GetObjectTagging	Implemented
GetObjectTorrent	Known difference	Source inspection: Returns a synthetic, name-based torrent-shaped payload with a fixed zero object length; it does not describe the actual object content or establish working torrent distribution.
GetPublicAccessBlock	Implemented
HeadBucket	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — checked an existing bucket.
HeadObject	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — returned the object's `ContentLength`, `ETag`, `ContentType` and `ServerSideEncryption`. The `AES256` value doesn't establish encryption at rest.
ListBucketAnalyticsConfigurations	Implemented
ListBucketIntelligentTieringConfigurations	Implemented
ListBucketInventoryConfigurations	Implemented
ListBucketMetricsConfigurations	Implemented
ListBuckets	Implemented
ListDirectoryBuckets	Implemented
ListMultipartUploads	Implemented
ListObjectAnnotations	Not implemented
ListObjectVersions	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — listed both version IDs of a key put twice in a versioned bucket. Reading the older version failed: see `GetObject`.
ListObjects	Implemented
ListObjectsV2	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — showed an empty destination bucket in the DataSync example and found an object delivered in a Data Firehose diagnostic. Pagination and other listing variants weren't checked.
ListParts	Implemented
PutBucketAbac	Implemented
PutBucketAccelerateConfiguration	Implemented
PutBucketAcl	Implemented
PutBucketAnalyticsConfiguration	Implemented
PutBucketCors	Implemented
PutBucketEncryption	Implemented
PutBucketIntelligentTieringConfiguration	Implemented
PutBucketInventoryConfiguration	Implemented
PutBucketLifecycle	Implemented
PutBucketLifecycleConfiguration	Implemented
PutBucketLogging	Implemented
PutBucketMetricsConfiguration	Implemented
PutBucketNotification	Implemented
PutBucketNotificationConfiguration	Implemented
PutBucketOwnershipControls	Implemented
PutBucketPolicy	Implemented
PutBucketReplication	Implemented
PutBucketRequestPayment	Implemented
PutBucketTagging	Implemented
PutBucketVersioning	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — recorded versioning on a bucket, and two puts of one key then gave two version IDs.
PutBucketWebsite	Implemented
PutObject	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — stored a 26-byte object that `GetObject` returned byte for byte.
PutObjectAcl	Implemented
PutObjectAnnotation	Not implemented
PutObjectLegalHold	Implemented
PutObjectLockConfiguration	Implemented
PutObjectRetention	Implemented
PutObjectTagging	Implemented
PutPublicAccessBlock	Implemented
RenameObject	Implemented
RestoreObject	Implemented
SelectObjectContent	Known difference	Source inspection: Returns the stored object body without evaluating the SQL expression. This cannot validate SQL filtering. The wire-level event stream was not newly tested.
UpdateBucketMetadataAnnotationTableConfiguration	Not implemented
UpdateBucketMetadataInventoryTableConfiguration	Implemented
UpdateBucketMetadataJournalTableConfiguration	Implemented
UpdateObjectEncryption	Implemented
UploadPart	Implemented	Local observation: Vera 1.2.0 preview, 5 November 2026 — a single 14-byte part was uploaded, the upload completed and the object read back. Large parts, several parts, concurrency and failure handling weren't checked.
UploadPartCopy	Implemented
WriteGetObjectResponse	Implemented