1 files changed, 79 insertions, 0 deletions
diff --git a/imagebuild/common/generate_upper_constraints.sh b/imagebuild/common/generate_upper_constraints.sh
new file mode 100755
index 00000000..cd61b784
--- /dev/null
+++ b/imagebuild/common/generate_upper_constraints.sh
@@ -0,0 +1,79 @@
+#!/bin/bash -eu
+
+SCRIPT_NAME=$(basename $0)
+COMMON_ROOT=$(dirname $0)
+DESTINATION="$1"
+TOX_INI_UPPER_CONSTRAINT_URL="$(${COMMON_ROOT}/extract_upper_constraints_from_tox_ini.sh ${COMMON_ROOT}/../../tox.ini)"
+
+copy() {
+  local src=$1
+  local destination=$2
+
+  if test -z "${src}"; then
+    return 1
+  fi
+
+  if test -e "${src}"; then
+    log "File '${src}' exists. Using as upper-constraints."
+    cp "${src}" "${destination}"
+  else
+    log "File '${src}' not found. Skipping local file strategy."
+    return 1
+  fi
+  return 0
+}
+
+download() {
+  local url=$1
+  local destination=$2
+
+  if test -z "${url}"; then
+     return 1
+  else
+    log "Downloading from '${url}'"
+    curl ${url} -o "${destination}"
+  fi
+  return 0
+}
+
+log() {
+  echo "${SCRIPT_NAME}: ${@}"
+}
+
+fail() {
+  log ${@}
+  exit 1
+}
+
+upper_constraints_is_not_null() {
+  test "${UPPER_CONSTRAINTS_FILE:-""}" != ""
+}
+
+copy_uc() {
+  copy "${UPPER_CONSTRAINTS_FILE:-""}" "${DESTINATION}"
+}
+
+download_uc() {
+  download "${UPPER_CONSTRAINTS_FILE:-""}" "${DESTINATION}"
+}
+
+copy_new_requirements_uc() {
+  copy "/opt/stack/new/requirements/upper-constraints.txt" "${DESTINATION}"
+}
+
+download_from_tox_ini_url() {
+  log "tox.ini indicates '${TOX_INI_UPPER_CONSTRAINT_URL}' as fallback."
+  download "${TOX_INI_UPPER_CONSTRAINT_URL}" "${DESTINATION}"
+}
+
+log "Generating local constraints file..."
+
+if upper_constraints_is_not_null; then
+  log "UPPER_CONSTRAINTS_FILE is defined as '${UPPER_CONSTRAINTS_FILE:-""}'"
+  copy_uc || download_uc || fail "Failed to copy or download file indicated in UPPER_CONSTRAINTS_FILE."
+else
+  log "UPPER_CONSTRAINTS_FILE is not defined. Using fallback strategies."
+
+  copy_new_requirements_uc || \
+  download_from_tox_ini_url || fail "Failed to download upper-constraints.txt from '${TOX_INI_UPPER_CONSTRAINT_URL}'."
+fi