Retry CI pip installs of uv past PyPI download blips

.github/workflows/ci.yml

@@ -1375,14 +1375,15 @@ jobs:
         env:
           UV_TEST_VERSION: ${{ matrix.uv }}
         run: |
-          python -m pip install --disable-pip-version-check --upgrade pip "uv==$UV_TEST_VERSION"
+          scripts/pip-install-retry.sh --upgrade pip "uv==$UV_TEST_VERSION"
           uv --version
 
       - name: Install uv (PDM / Hatch legs)
         if: matrix.pdm != '' || matrix.hatch != ''
         # The suites bootstrap the pinned PDM / Hatch into their own venv
         # with uv; this uv is tooling, not the release under test.
-        run: python -m pip install uv==0.11.19
+        shell: bash
+        run: scripts/pip-install-retry.sh uv==0.11.19
 
       - name: Install pinned Poetry
         if: matrix.poetry != ''
@@ -1394,7 +1395,7 @@ jobs:
         env:
           POETRY_TEST_VERSION: ${{ matrix.poetry }}
         run: |
-          python -m pip install uv==0.11.19
+          scripts/pip-install-retry.sh uv==0.11.19
           case "$POETRY_TEST_VERSION" in 1.0.*|1.1.*) py=3.8.20 ;; *) py=3.12 ;; esac
           uv venv "$RUNNER_TEMP/poetry" --python "$py"
           extra=""; [ "$POETRY_TEST_VERSION" = "1.2.2" ] && extra="cleo==1.0.0a5"
@@ -2479,7 +2480,7 @@ jobs:
 
       - name: Install uv
         if: steps.gate.outputs.run == 'true'
-        run: python -m pip install --disable-pip-version-check uv && uv --version
+        run: scripts/pip-install-retry.sh uv && uv --version
 
       - name: Setup Ruby
         if: steps.gate.outputs.run == 'true'

.github/workflows/pdm-compatibility.yml

@@ -129,7 +129,7 @@ jobs:
           python-version: '3.12'
       # uv bootstraps every pinned PDM release (and its interpreter) itself;
       # pinning uv keeps the bootstrap reproducible across runner images.
-      - run: python -m pip install uv==0.11.19
+      - run: scripts/pip-install-retry.sh uv==0.11.19
       - name: Exercise the native PDM installers
         shell: bash
         env:
@@ -226,7 +226,7 @@ jobs:
       - uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5
         with:
           python-version: '3.12'
-      - run: python -m pip install uv==0.11.19
+      - run: scripts/pip-install-retry.sh uv==0.11.19
       - name: Real-PDM hosted + vendored flows with manifest-less VEX
         env:
           SOCKET_PATCH_PDM_E2E_REQUIRED: '1'

.github/workflows/poetry-compatibility.yml

@@ -110,7 +110,7 @@ jobs:
         uses: ./.github/actions/pin-socket-hosts
       # uv bootstraps every pinned Poetry release (and its interpreter)
       # itself; pinning uv keeps the bootstrap reproducible.
-      - run: python -m pip install uv==0.11.19
+      - run: scripts/pip-install-retry.sh uv==0.11.19
       - name: Exercise the native Poetry installers
         shell: bash
         env:

scripts/pip-install-retry.sh

@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+# `python -m pip install` that survives a PyPI download blip.
+#
+#   scripts/pip-install-retry.sh <pip install args...>
+#
+# pip's own `--retries` covers failed connections, not a body cut off
+# mid-download: an `IncompleteRead` from files.pythonhosted.org aborts the
+# install at once ("Could not install packages due to an OSError:
+# Connection broken: IncompleteRead"). One such cut evicted a merge-queue
+# entry in hosted-e2e, so the CI tool installs go through here: up to 4
+# attempts with a growing pause. The args are passed through unchanged, so
+# a pinned `pkg==X.Y.Z` stays pinned.
+set -euo pipefail
+
+if [ "$#" -eq 0 ]; then
+  echo "usage: $0 <pip install args...>" >&2
+  exit 2
+fi
+
+attempts=4
+for attempt in $(seq 1 "$attempts"); do
+  if python -m pip install --disable-pip-version-check "$@"; then
+    exit 0
+  fi
+  if [ "$attempt" = "$attempts" ]; then
+    echo "::error::pip install $* failed on all $attempts attempts"
+    exit 1
+  fi
+  echo "::warning::pip install $* attempt $attempt failed; retrying"
+  sleep $((attempt * 10))
+done