Convert between API Blueprint (*.apib), OpenAPI 2.0/3.0/3.1, and AsyncAPI 2.x/3.0 specifications.

• API Blueprint and MSON
• AsyncAPI v3.0
• AsyncAPI v2.6
• OpenAPI v3.1.x
• OpenAPI v3.0.x
• OpenAPI v2.0 (Swagger)

Installation

Using Go

go install github.com/amer8/apibconv/cmd/apibconv@latest

Using Docker

Pull the image

docker pull ghcr.io/amer8/apibconv:latest

Run directly

docker run --rm -v $(pwd):/data -w /data ghcr.io/amer8/apibconv -o openapi.json api.apib

Download Binary

Download pre-built binaries from GitHub Releases:

• published release assets cover Linux, macOS, and Windows on x64 and arm64
• each platform archive ships with a matching *_checksums.txt file for targeted verification
• signed releases also ship a matching *.sigstore.json bundle for the checksum file
• each release also includes a CycloneDX bom.json SBOM

Older releases may only have the checksum file. In that case, verify the checksum directly.

Example verification:

cosign verify-blob \
  --bundle apibconv_X.Y.Z_Linux_x86_64.tar.gz_checksums.txt.sigstore.json \
  --certificate-identity "https://github.com/amer8/apibconv/.github/workflows/release.yml@refs/tags/vX.Y.Z" \
  --certificate-oidc-issuer "https://token.actions.githubusercontent.com" \
  apibconv_X.Y.Z_Linux_x86_64.tar.gz_checksums.txt

sha256sum -c apibconv_X.Y.Z_Linux_x86_64.tar.gz_checksums.txt

Usage

CLI Usage

The tool automatically detects the input format based on file extension and content. It supports both file arguments and stdin.

Usage: apibconv [OPTIONS] [INPUT_FILE]

Arguments:
  INPUT_FILE
      Input specification file (OpenAPI, AsyncAPI, or API Blueprint)

Options:
  -o, --output FILE
      Output file path (required for conversion)
  
  --to FORMAT
      Target format: openapi, asyncapi, apib
      Auto-detected from --output extension if not specified
  
  -e, --encoding FORMAT
      Output encoding: json, yaml (default: auto-detected from output extension)
  
  --validate
      Validate input without converting. Pinned OpenAPI and AsyncAPI versions
      are checked against specification JSON Schemas plus model validation
  
  -v, --version
      Print version information
  
  -h, --help
      Show this help message

AsyncAPI Options:
  --protocol PROTO
      Protocol: ws, wss, mqtt, kafka, amqp, http, https, auto (required)
  
  --asyncapi-version VERSION
      Version: 2.6, 3.0 (default: "2.6")

OpenAPI Options:
  --openapi-version VERSION
      Version: 2.0, 3.0, 3.1 (default: "3.0")

Examples:
  apibconv -o output.json spec.apib
  apibconv -o output.yaml --protocol ws spec.apib
  apibconv -o output.json --to openapi --openapi-version 3.1 < spec.apib
  apibconv --validate spec.json

GitHub Actions

For GitHub Actions, prefer the first-party install action over go install ...@latest. Pin the action itself to a full commit SHA and pin the binary version to a release tag.

- name: Install apibconv
  uses: amer8/apibconv@<full-commit-sha>
  with:
    version: vX.Y.Z

- name: Convert OpenAPI to API Blueprint
  run: apibconv -o api-blueprint.apib openapi.json

The action downloads the published release asset for the current runner, verifies its SHA-256 checksum, and when the release includes a Sigstore bundle it also verifies the checksum signature with cosign against this repository's release workflow identity. Older releases without a bundle fall back to checksum-only verification with a warning. Published action assets target x64 and arm64 runners.

Go projects

This tool is designed for seamless integration with servers and CLI tools built in Go.

• Basic example
• Advanced example
• Plugin example

Contributing

Contributions are welcome! Please ensure:

1. All tests pass: go test ./...
2. Linter passes: golangci-lint run
3. Code coverage remains high

License

See LICENSE file for details.