oras resolve

Resolve a reference to a manifest digest.

Synopsis 

oras resolve <reference> [options]

Description

The resolve command resolves a reference (tag or digest) to its canonical manifest digest (SHA256).

This is useful for:

  • Getting the immutable digest for a tag
  • Verifying tag resolution
  • Pinning to specific versions in CI/CD pipelines

Arguments

<reference>

Reference to resolve in the format [registry/]repository[:tag|@digest].

Examples:

  • ghcr.io/myorg/artifact:latest
  • ghcr.io/myorg/artifact@sha256:abc123... (returns the same digest)

Options

Platform Options

--platform <os/arch>

Specify platform for multi-platform artifacts (e.g., linux/amd64, linux/arm64).

When resolving an image index (multi-platform image), this selects a specific platform manifest.

Example: --platform linux/arm64

Remote Options

--username <username>, -u

Registry username.

--password <password>, -p

Registry password.

--password-stdin

Read password from stdin.

--insecure

Skip TLS certificate verification.

--plain-http

Use HTTP instead of HTTPS.

--ca-file <file>

Path to custom CA certificate.

--registry-config <file>

Path to registry configuration file (default: ~/.docker/config.json).

Common Options

--debug, -d

Enable debug logging to stderr.

--verbose, -v

Enable verbose output.

Examples

Resolve a tag 

oras resolve ghcr.io/myorg/artifact:latest

Output:

sha256:abc123def456...

Resolve with platform selection 

oras resolve ghcr.io/myorg/multiplatform:latest --platform linux/arm64

Resolve by digest (returns same digest) 

oras resolve ghcr.io/myorg/artifact@sha256:abc123...

Output:

sha256:abc123...

Resolve with authentication 

oras resolve ghcr.io/myorg/artifact:latest \
  --username myuser \
  --password-stdin

Use in scripts to pin versions 

# Get digest and use in pull
DIGEST=$(oras resolve ghcr.io/myorg/artifact:latest)
oras pull ghcr.io/myorg/artifact@$DIGEST

Exit Codes

  • 0 — Success (digest printed to stdout)
  • 1 — Network error, registry error, reference not found
  • 2 — Usage error (invalid reference)

Notes

  • Output is the digest only (no additional formatting)
  • For multi-platform images without --platform, the index digest is returned
  • Use with --platform to resolve a specific platform manifest within an index
  • Resolving by digest simply returns the same digest (validates it exists)

See Also