Source Connector

The S3 Source Connector connects to an S3 bucket with the provided configurations, using aws.bucket, aws.access-key-id,aws.secret-access-key and aws.region. Then will call Open to start the connection. If the bucket doesn't exist, or the permissions fail, then the Open method will fail, and the Connector will not be ready to Read.

Change Data Capture (CDC)

This connector implements CDC features for S3 by scanning the bucket for changes every polling-period and detecting any change that happened after a certain timestamp. These changes (update, delete, insert) are then inserted into a buffer that is checked on each Read request.

• To capture "delete" actions, the S3 bucket versioning must be enabled, and the output record will have a metadata of "action":"delete".
• To capture "insert" or "update" actions, the bucket versioning doesn't matter, and no metadata is added for these actions.

Position Handling

The connector goes through two modes:

• Snapshot mode: which loops through the S3 bucket and returns the objects that are already in there. The Position during this mode is the object key attached to an underscore, an "s" for snapshot, and the maxLastModifiedDate found so far. As an example: "thisIsAKeys12345", which makes the connector know at what mode it is and what object it last read. The _maxLastModifiedDate will be used when changing to CDC mode, the iterator will capture changes that happened after that.

• CDC mode: this mode iterates through the S3 bucket every polling-period and captures new actions made on the bucket. the Position during this mode is the object key attached to an underscore, a "c" for CDC, and the object's lastModifiedDate in seconds. As an example: "thisIsAKeyc1634049397". This position is used to return only the actions with a _lastModifiedDate higher than the last record returned, which will ensure that no duplications are in place.

Record Keys

The S3 object key uniquely identifies the objects in an Amazon S3 bucket, which is why a record key is the key read from the S3 bucket.

Configuration

The config passed to Open can contain the following fields.

name	description	required	example
aws.access-key-id	AWS access key id	yes	"THE_ACCESS_KEY_ID"
aws.secret-access-key	AWS secret access key	yes	"SECRET_ACCESS_KEY"
aws.region	the AWS S3 bucket region	yes	"us-east-1"
aws.bucket	the AWS S3 bucket name	yes	"bucket_name"
polling-period	polling period for the CDC mode, formatted as a time.Duration string. default is "1s"	no	"2s", "500ms"

Known Limitations

• If a pipeline restarts during the snapshot, then the connector will start scanning the objects from the beginning of the bucket, which could result in duplications.

Destination

The S3 Destination Connector connects to an S3 bucket with the provided configurations, using aws.bucket, aws.access-key-id,aws.secret-access-key and aws.region. Then will call Open to start the connection. If the bucket doesn't exist, or the permissions fail, then the Open method will fail, and the Connector will not be ready to Write.

Writer

The S3 destination writer has a buffer with the size of buffer-size, for each time Write is called, a new record is added to the buffer. When the buffer is full, all the records from it will be written to the S3 bucket configured.

Configuration

The config passed to Open can contain the following fields.

name	description	required	example
aws.access-key-id	AWS access key id	yes	"THE_ACCESS_KEY_ID"
aws.secret-access-key	AWS secret access key	yes	"SECRET_ACCESS_KEY"
aws.region	the AWS S3 bucket region	yes	"us-east-1"
aws.bucket	the AWS S3 bucket name	yes	"bucket_name"
format	the destination format, either "json" or "parquet"	yes	"json"
buffer-size	the buffer size {when full, the files will be written to destination}, default is "1000", max is "100000"	no	"100"
prefix	the key prefix for S3 destination	no	"conduit-"