updated build backend (#7502)

* updated build backend

* use poetry_version.txt for the ci poetry version

* set ubuntu version

Co-authored-by: Joseph Juzl <joejuzl@gmail.com>

.github/poetry_version.txt

@@ -0,0 +1,2 @@
+# The poetry version is stored in a separate file due to the https://github.com/python-poetry/poetry/issues/3316
+poetry-version=1.1.4

.github/workflows/continous-integration.yml

@@ -430,7 +430,7 @@ jobs:
 
   docker:
     name: Build Docker
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     needs: [changes, build_docker_base_images_and_set_env]
     env:
       IMAGE_TAG: ${{ needs.build_docker_base_images_and_set_env.outputs.image_tag }}

pyproject.toml

@@ -1,7 +1,6 @@
 [build-system]
-# keep this in sync with the version in pyproject.toml and Dockerfile.base
-requires = [ "poetry>=1.1.4",]
-build-backend = "poetry.masonry.api"
+requires = [ "poetry-core>=1.0.0",]
+build-backend = "poetry.core.masonry.api"
 
 [tool.black]
 line-length = 88

scripts/poetry-version.sh

@@ -1,13 +1,17 @@
 #!/usr/bin/env python
 
-"""Extract the poetry version from pyproject.toml. Used in e.g. github workflows."""
+"""Extract the poetry version from .github/poetry_version.txt. Used in e.g. github workflows."""
 
+import pathlib
 import sys
 import re
 
+# The poetry version is stored in the .github/poetry_version.txt file due to the https://github.com/python-poetry/poetry/issues/3316
+poetry_version_txt = pathlib.Path(__file__).parent.parent / ".github" / "poetry_version.txt"
+
 if __name__ == "__main__":
-    version_regex = r'"poetry[^\"]*=([^\"]+)"'
-    with open("pyproject.toml") as f:
+    version_regex = r'poetry-version=(.*)'
+    with poetry_version_txt.open() as f:
         for line in f:
             m = re.search(version_regex, line)
             if m: