net.s3 is an S3-compatible client written in pure V.

It speaks the AWS Signature Version 4 protocol on top of crypto.hmac and crypto.sha256, with no third-party dependencies. The same client targets any S3-compatible endpoint (hosted or self-hosted) by configuring the right endpoint, region and credentials.

Quick start

import net.s3

c := s3.new_client(s3.Credentials{
    endpoint:          'https://s3.example.com'
    access_key_id:     '...'
    secret_access_key: '...'
    bucket:            'my-bucket'
})

c.put('hello.txt', 'Hi from V!'.bytes())!
text := c.get_string('hello.txt')!
url := c.presign('hello.txt', expires_in: 3600)!

Credentials from the environment

Credentials.from_env() resolves each field from the first non-empty provider-specific environment variable, so the same code works against AWS, self-hosted and managed S3 services without reconfiguration:

import net.s3

c := s3.new_client(s3.Credentials.from_env())

Supported variables (first non-empty wins per field):

• key id: S3_ACCESS_KEY_ID, AWS_ACCESS_KEY_ID, CELLAR_ADDON_KEY_ID, SCW_ACCESS_KEY, B2_APPLICATION_KEY_ID, R2_ACCESS_KEY_ID, SPACES_KEY
• secret: S3_SECRET_ACCESS_KEY, AWS_SECRET_ACCESS_KEY, CELLAR_ADDON_KEY_SECRET, SCW_SECRET_KEY, B2_APPLICATION_KEY, R2_SECRET_ACCESS_KEY, SPACES_SECRET
• session token: S3_SESSION_TOKEN, AWS_SESSION_TOKEN
• region: S3_REGION, AWS_REGION, AWS_DEFAULT_REGION, SCW_DEFAULT_REGION
• bucket: S3_BUCKET
• endpoint: S3_ENDPOINT, AWS_ENDPOINT, AWS_ENDPOINT_URL, CELLAR_ADDON_HOST, B2_ENDPOINT, R2_ENDPOINT, SPACES_ENDPOINT

Multipart upload

upload_file automatically picks single-shot or multipart based on file size. For finer control, start_multipart returns a stateful MultipartUploader that streams chunks generated on the fly:

import net.s3

c := s3.new_client(s3.Credentials.from_env())
c.upload_file('big.bin', '/path/to/big.bin', s3.PutOptions{
    content_type: 'application/octet-stream'
})!

s3:// URLs

Importing net.s3 registers an s3:// scheme handler with net.http, so the generic http.fetch(url: 's3://...') route works out of the box. There is also a direct s3.fetch helper:

import net.s3

resp := s3.fetch('s3://my-bucket/hello.txt')!
println(resp.body.bytestr())

File handle

Client.file(key) returns a small File reference for ergonomic call sites:

import net.s3

c := s3.new_client(s3.Credentials.from_env())
f := c.file('hello.txt')
text := f.text()!
url := f.presign(expires_in: 3600)!

Tests

The unit suite is offline and runs by default:

v test vlib/net/s3/

The integration suite is gated on S3_INTEGRATION=1 and exercises the client against a live endpoint:

S3_INTEGRATION=1 \
S3_HOST=https://s3.example.com \
S3_KEY_ID=... S3_KEY_SECRET=... \
S3_BUCKET=v-s3-tests \
v test vlib/net/s3/integration_test.v