xdef

README

xdef

Single source of truth for shared definitions used across all ctx42 modules: label names, environment variable names, placeholder values, and helpers for reading variables from a process environment slice.

Import

import "github.com/ctx42/xdef/pkg/xdef"

Usage

Read image metadata from a container's environment, falling back to sensible defaults when the variables are absent:

env := os.Environ()

// Returns OCI_IMAGE_CREATED value, or current UTC time in RFC3339Nano
// format (truncated to millisecond precision) if not set.
created := xdef.Created(env)

// Returns OCI_IMAGE_REF_NAME value, or a unique "no-ccid-<timestamp>"
// tag if not set.
refName := xdef.ImgRefName(env)

Placeholder constants are provided for unknown build metadata:

labels := map[string]string{
    xdef.LabImgRev:     xdef.PhHash,
    xdef.LabImgVer:     xdef.PhRev,
    xdef.LabImgCreated: xdef.PhTime,
}

Labels and Environment Variables

OCI label	Env variable
org.opencontainers.image.created	OCI_IMAGE_CREATED
org.opencontainers.image.title	OCI_IMAGE_TITLE
org.opencontainers.image.description	OCI_IMAGE_DESCRIPTION
org.opencontainers.image.authors	OCI_IMAGE_AUTHORS
org.opencontainers.image.source	OCI_IMAGE_SOURCE
org.opencontainers.image.version	OCI_IMAGE_VERSION
org.opencontainers.image.revision	OCI_IMAGE_REVISION
org.opencontainers.image.ref.name	OCI_IMAGE_REF_NAME
org.opencontainers.image.base.name	OCI_IMAGE_BASE_NAME

License

MIT — see LICENSE.