Enable package and offline_package to support nested project structures

README.md

@@ -226,12 +226,15 @@ path: ..
 offline_packages:
 - source: paketo-buildpacks/adoptium
   target: gcr.io/tanzu-buildpacks/adoptium
+  path: subdir/adoptium
   platform:
     os: linux
 ```
 
 `offline_packages` is a list of objects that describe a `source` GitHub repository and a `target` Docker registry location.  If defined, each object will create a `create-package` workflow that is responsible for detecting a new online buildpackage release and creating a matching offline buildpackage release and publishing it.
 
+`path` is the path to the buildpack's directory relative to the repository's root.
+
 `platform` describes what platform the created package should be built for. `os` can be set to `linux` or `windows` (`linux` by default).
 
 #### `republish_images`

octo/create-package.sh

@@ -4,15 +4,18 @@ set -euo pipefail
 
 if [[ "${INCLUDE_DEPENDENCIES}" == "true" ]]; then
   create-package \
+    --source ${SOURCE_PATH:-.} \
     --cache-location "${HOME}"/carton-cache \
     --destination "${HOME}"/buildpack \
     --include-dependencies \
     --version "${VERSION}"
 else
   create-package \
+    --source ${SOURCE_PATH:-.} \
     --destination "${HOME}"/buildpack \
     --version "${VERSION}"
 fi
 
-[[ -e package.toml ]] && cp package.toml "${HOME}"/package.toml
+PACKAGE_FILE=${SOURCE_PATH:-.}/package.toml
+[[ -e ${PACKAGE_FILE} ]] && cp ${PACKAGE_FILE} "${HOME}"/package.toml
 printf '[buildpack]\nuri = "%s"\n\n[platform]\nos = "%s"\n' "${HOME}"/buildpack "${OS}" >> "${HOME}"/package.toml

octo/descriptor.go

@@ -83,9 +83,10 @@ type Dependency struct {
 }
 
 type OfflinePackage struct {
-	Source   string
-	Target   string
-	Platform Platform
+	Source     string
+	Target     string
+	SourcePath string `yaml:"source_path"`
+	Platform   Platform
 }
 
 type RepublishImage struct {

octo/offline_packages.go

@@ -112,6 +112,7 @@ func contributeOfflinePackage(descriptor Descriptor, offlinePackage OfflinePacka
 							"INCLUDE_DEPENDENCIES": "true",
 							"OS":                   offlinePackage.Platform.OS,
 							"VERSION":              "${{ steps.version.outputs.version }}",
+							"SOURCE_PATH":          offlinePackage.SourcePath,
 						},
 					},
 					{