Architecture — CLI Client (client/)

The Plik command-line client. For system-wide overview, see the root ARCHITECTURE.md.

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Structure

client/
├── plik.go        ← main CLI logic (docopt-based argument parsing + upload flow)
├── config.go      ← configuration loading (.plikrc)
├── progress.go    ← upload progress bar
├── update.go      ← self-update mechanism
├── archive/       ← archive backends (tar, zip)
├── crypto/        ← crypto backends (openssl, pgp)
├── .plikrc        ← example client configuration
├── plik.sh        ← bash upload wrapper
├── test.sh        ← CLI integration tests
├── test_downgrade.sh  ← client version downgrade tests
└── test_upgrade.sh    ← client version upgrade tests

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Key Components

CLI Entry Point (plik.go)

Uses docopt-go for argument parsing. The main flow:

1. Parse CLI args (file paths, options like --oneshot, --stream, --ttl, etc.)
2. Load config from .plikrc (or PLIKRC env var)
3. Handle special modes: --update (self-update), --version
4. Create upload via the Go library (plik/)
5. Add files (with optional archive/encrypt preprocessing)
6. Upload files with progress bars
7. Print download URLs

Configuration (config.go)

Config is a TOML file loaded from (in order):

1. PLIKRC environment variable
2. ~/.plikrc
3. /etc/plik/plikrc

Key config fields: URL (server), Token (upload token), archive/crypto defaults.

Archive Backends (archive/)

Backend	Description
tar	Create tar archives with compression (gzip, bzip2, xz, lzip, lzma, lzop)
zip	Create zip archives

Archives wrap multiple files/directories into a single upload file.

Crypto Backends (crypto/)

Backend	Description
openssl	Symmetric encryption via OpenSSL CLI (configurable cipher)
pgp	Asymmetric encryption via GPG/PGP (recipient-based)

Encryption wraps the file data stream before upload.

Self-Update (update.go)

The client can update itself by downloading the latest matching binary from the configured Plik server. It compares versions and replaces the current binary in-place.

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Integration Tests

• test.sh — comprehensive CLI integration tests (requires a running server)
• test_upgrade.sh / test_downgrade.sh — version compatibility tests (stale, unused since ~2021)