mongocp

README

mongocp

mongocp is a fast CLI tool for copying MongoDB databases and collections from one server to another.

It is designed for migration and replication workflows where you want filtering, dry-run safety, and clear progress visibility per worker.

Features

• Copy databases and collections from source to destination MongoDB.
• Include/exclude databases with wildcard patterns (for example: dev*, prod_*).
• Exclude system databases (admin, local, config) by default.
• Parallel copy with configurable workers.
• Default progress UI with stable one-line-per-worker bars.
• Copies secondary indexes.
• Dry-run mode to preview what would be copied.

Installation

Install Latest

go install github.com/kstieger/mongocp/cmd/mongocp@latest

Install A Specific Version

go install github.com/kstieger/mongocp/cmd/mongocp@v0.1.0

After installation, ensure your Go bin directory is in PATH.

Usage

Basic

mongocp -src "mongodb://root:xxxxx@source:27017/" -dst "mongodb://root:xxxxx@dest:27017/"

Filtered Copy

mongocp \
  -src "mongodb://root:xxxxx@source:27017/" \
  -dst "mongodb://root:xxxxx@dest:27017/" \
  -include-dbs "dev_*" \
  -exclude-dbs "dev_tmp*" \
  -worker 8

Dry Run

mongocp \
  -src "mongodb://root:xxxxx@source:27017/" \
  -dst "mongodb://root:xxxxx@dest:27017/" \
  -include-dbs "dev_*" \
  -dry-run

Progress And Logging

• Progress mode is enabled by default.
• In default progress mode, regular logs are suppressed and only fatal failures are printed.
• Setting -log-level (or -loglevel) disables progress mode and enables normal logging.

Flags

• -src (required): source MongoDB URI.
• -dst (required): destination MongoDB URI.
• -include-dbs: comma-separated include wildcard patterns.
• -exclude-dbs: comma-separated exclude wildcard patterns.
• -exclude-system_dbs: exclude admin, local, config (default: true).
• -worker: number of parallel workers (default: 10).
• -dry-run: preview copy operations without writing data.
• -log-level: logging level (info, debug, warn, error); disables progress mode when set.
• -loglevel: alias for -log-level.
• -version: print version information and exit.

Releases

Pushing a v* tag (via task release) triggers the Release GitHub Actions workflow, which cross-compiles and publishes prebuilt binaries as GitHub Release assets for:

• Linux: amd64, arm64
• macOS (Darwin): amd64, arm64
• Windows: amd64, arm64

Contributing

Contributions are welcome! To get started:

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Submit a pull request

Local Tasks

This project uses Task to run common developer commands:

task build        # cross-compile for linux/darwin/windows (amd64+arm64)
task format       # gofmt + go mod tidy
task lint         # golangci-lint
task vulncheck    # govulncheck
task test         # go test -race with coverage
task pre-checkin  # format, lint, vulncheck, and test
task release      # tag and push a release; CI builds the binaries and publishes the GitHub Release

Security Before Push

Before committing and pushing:

1. Run task pre-checkin (formatting, linting, vulnerability scanning, and tests).
2. Scan for secrets (for example with gitleaks detect).
3. Verify docs/examples do not include real credentials, tokens, or private keys.

License

MIT. See LICENSE.