Archive relational data to Amazon S3.
This project provides the chiv
package and a simple CLI wrapper of the same name. It requires Go 1.13.
Use chiv
to download relational data from a database and format it before uploading to Amazon S3.
Built-in formats include CSV, YAML and JSON.
Custom formats are also supported through the Formatter
interface.
import "gavincabbage.com/chiv"
Provide a database and upload manager to upload a table to an S3 bucket in the default CSV format.
db, _ := sql.Open(config.driver, config.url)
client := s3.New(session.NewSessionWithOptions(session.Options{}))
uploader := s3manager.NewUploaderWithClient(client)
chiv.Archive(db, uploader, "table", "bucket")
Use options to configure the archival format, upload key, null placeholder, etc.
chiv.Archive(db, uploader, "table", "bucket"
chiv.WithFormat(chiv.JSON),
chiv.WithKey("2019/september/monthly_archive.json"),
chiv.WithNull("empty"),
)
For multiple uploads using the same database and S3 clients, construct an Archiver
. Options provided during
construction of an Archiver
can be overridden in individual archival calls.
a := chiv.NewArchiver(db, uploader, chiv.WithFormat(chiv.YAML))
a.Archive("first_table", "bucket")
a.Archive("second_table", "bucket")
a.Archive("second_table", "bucket", chiv.WithFormat(chiv.JSON), chiv.WithKey("second_table.json"))
Custom queries can be archived using the ArchiveRows
family of functions.
rows, _ := db.Exec("SELECT * FROM table and JOIN all the things...")
chiv.ArchiveRows(rows, uploader, "bucket")
Context-aware versions are also provided, e.g. ArchiveWithContext
, ArchiveRowsWithContext
, etc.
See the unit and integration tests for additional examples.
Custom formats can be used by implementing the FormatterFunc
and Formatter
interfaces.
The optional Extensioner
interface can be implemented to allow a Formatter
to provide a default extension.
See the three built-in formats for examples.
A simple CLI wrapping the package is also included.
NAME:
chiv - Archive relational data to Amazon S3
USAGE:
chiv [flags...]
VERSION:
vX.Y.Z
GLOBAL OPTIONS:
--database value, -d value database connection string [$DATABASE_URL]
--table value, -t value database table to archive
--bucket value, -b value upload S3 bucket name
--driver value, -r value database driver type: postgres or mysql (default: "postgres")
--columns value, -c value database columns to archive, comma-separated
--format value, -f value upload format: csv, yaml or json (default: "csv")
--key value, -k value upload key
--extension value, -e value upload extension
--null value, -n value upload null value
--help, -h show usage details
--version, -v print the version
This package ties together three components of what is essentially an ETL operation:
- Extract database rows with a
Database
orRows
Database
may be a*sql.DB
,*sql.Conn
,*sql.Tx
, etc.
- Transform data into an upload format with a
Formatter
- Load the formatted data into S3 with a
Uploader
Uploader
is typically an*s3manager.Uploader
An io.Pipe
is used to guarantee a cap on total memory usage by chiv
itself.
A benchmark
is provided to profile the package's memory usage.
Total memory usage of the archival process can be further controlled by
configuring the S3 upload manager.
Tests are segregated by build tags.
Run unit tests:
go test -tags=unit ./...
Use docker-compose to run the full suite of unit and integration tests:
docker-compose up --exit-code-from test --build
Run benchmarks:
go test -v -p 1 -tags=benchmark,unit -run=Benchmark -benchmem -bench=.
This project uses GitHub Actions for CI. Linting, unit tests, integration tests and benchmarks are run for each push or pull request.
Tagged releases are built automatically by GoReleaser.
Contributions in the form of comments, issues or pull requests are very welcome.
If you use this package I would love to hear from you!