ci: mirror release artifacts to Cloudflare R2 (#1114)

Mirrors every release artifact into Cloudflare R2 alongside the existing AWS S3
upload, so both buckets carry the same objects during a parallel period. S3 is
untouched and stays authoritative for now; once R2 is confirmed complete it can
be dropped by deleting the `blobs:` block and pointing this at R2 alone.

### Why `publishers:` and not a second `blobs:` entry

goreleaser's blob pipe authenticates from the global `AWS_*` environment and has
no per-entry credential fields, so two different credential sets (AWS S3 and
Cloudflare R2) cannot coexist in `blobs:`. Custom publishers do support
per-entry `env:`, which is the supported way to isolate the two.

### Why `curl --aws-sigv4` and not `aws`/`rclone`

The CI image `docker.gitea.com/runner-images:ubuntu-latest` ships none of `aws`,
`rclone`, `s3cmd` or `mc`, but does ship curl 8.5 with `--aws-sigv4`. This keeps
the change zero-install. Credentials are fed to curl through a config file on
stdin rather than argv, so they never appear in the process list.

### Behaviour

- Object layout is identical to S3 (`gitea-runner/<version>/<artifact>`), so
  migrating consumers later means changing only the host, not the path.
- Nightly gets R2 too, matching the existing nightly-to-S3 behaviour.
- Missing R2 configuration fails the build. Because custom publishers run as the
  very last step of the publish pipeline, a preflight `--check-config` step runs
  right after checkout so the failure happens before anything is built or
  published rather than after the release already exists.
- Verified against a local MinIO instance (site region `auto`, matching R2):
  successful upload byte-compared after download, plus the missing-variable,
  wrong-credentials, missing-file and bad-argument paths.

### Required repository secrets

These must be configured before the next release run, otherwise the new
preflight step will fail the workflow:

- `R2_ENDPOINT` (full base URL, e.g. `https://<account>.r2.cloudflarestorage.com`)
- `R2_BUCKET`
- `R2_ACCESS_KEY_ID`
- `R2_SECRET_ACCESS_KEY`

### Known, deliberate wart

The publisher runs 109 times for 73 distinct object keys: goreleaser's release
pipe already registers `release.extra_files` as `UploadableFile` artifacts, and
`internal/exec` appends the publisher's own `extra_files` on top with no
de-duplication. It cannot be globbed away because `gobwas/glob` has no
substring-exclusion matcher, so `./**.sha256` cannot be narrowed to exclude
`*.xz.sha256`. It is harmless since PUT is idempotent, and the redundant
`./**.xz` glob is kept on purpose so the publisher declares its own complete
file set instead of implicitly depending on the `release:` block's globs. This
is documented in a comment above the block.

Reviewed-on: https://gitea.com/gitea/runner/pulls/1114
Reviewed-by: Zettat123 <39446+zettat123@noreply.gitea.com>

.gitea/workflows/release-nightly.yml

@@ -20,6 +20,18 @@ jobs:
       - uses: actions/checkout@v7
         with:
           fetch-depth: 0
+      # Custom publishers (the R2 mirror below) run as the very last
+      # step of goreleaser's publish pipeline, after the Gitea release
+      # has already been created and every artifact already uploaded
+      # to S3. Fail here instead, before anything is built or
+      # published, if the R2 secrets are missing.
+      - name: check R2 configuration
+        run: sh scripts/upload-r2.sh --check-config
+        env:
+          R2_ENDPOINT: ${{ secrets.R2_ENDPOINT }}
+          R2_BUCKET: ${{ secrets.R2_BUCKET }}
+          R2_ACCESS_KEY_ID: ${{ secrets.R2_ACCESS_KEY_ID }}
+          R2_SECRET_ACCESS_KEY: ${{ secrets.R2_SECRET_ACCESS_KEY }}
       - uses: actions/setup-go@v7
         with:
           go-version-file: "go.mod"
@@ -35,6 +47,10 @@ jobs:
           AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
           S3_REGION: ${{ secrets.AWS_REGION }}
           S3_BUCKET: ${{ secrets.AWS_BUCKET }}
+          R2_ENDPOINT: ${{ secrets.R2_ENDPOINT }}
+          R2_BUCKET: ${{ secrets.R2_BUCKET }}
+          R2_ACCESS_KEY_ID: ${{ secrets.R2_ACCESS_KEY_ID }}
+          R2_SECRET_ACCESS_KEY: ${{ secrets.R2_SECRET_ACCESS_KEY }}
           GORELEASER_FORCE_TOKEN: "gitea"
           GITEA_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 

.gitea/workflows/release-tag.yml

@@ -12,6 +12,18 @@ jobs:
       - uses: actions/checkout@v7
         with:
           fetch-depth: 0 # all history for all branches and tags
+      # Custom publishers (the R2 mirror below) run as the very last
+      # step of goreleaser's publish pipeline, after the Gitea release
+      # has already been created and every artifact already uploaded
+      # to S3. Fail here instead, before anything is built or
+      # published, if the R2 secrets are missing.
+      - name: check R2 configuration
+        run: sh scripts/upload-r2.sh --check-config
+        env:
+          R2_ENDPOINT: ${{ secrets.R2_ENDPOINT }}
+          R2_BUCKET: ${{ secrets.R2_BUCKET }}
+          R2_ACCESS_KEY_ID: ${{ secrets.R2_ACCESS_KEY_ID }}
+          R2_SECRET_ACCESS_KEY: ${{ secrets.R2_SECRET_ACCESS_KEY }}
       - uses: actions/setup-go@v7
         with:
           go-version-file: "go.mod"
@@ -34,6 +46,10 @@ jobs:
           AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
           S3_REGION: ${{ secrets.AWS_REGION }}
           S3_BUCKET: ${{ secrets.AWS_BUCKET }}
+          R2_ENDPOINT: ${{ secrets.R2_ENDPOINT }}
+          R2_BUCKET: ${{ secrets.R2_BUCKET }}
+          R2_ACCESS_KEY_ID: ${{ secrets.R2_ACCESS_KEY_ID }}
+          R2_SECRET_ACCESS_KEY: ${{ secrets.R2_SECRET_ACCESS_KEY }}
           GORELEASER_FORCE_TOKEN: "gitea"
           GITEA_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           GPG_FINGERPRINT: ${{ steps.import_gpg.outputs.fingerprint }}

.goreleaser.yaml

@@ -93,6 +93,37 @@ blobs:
       - glob: ./**.xz
       - glob: ./**.sha256
 
+# Mirrors the S3 `blobs:` upload above into Cloudflare R2 during the
+# parallel S3+R2 period (S3 will be removed once migration completes).
+# A second `blobs:` entry is impossible here since the blob pipe
+# authenticates from the global AWS_* env with no per-entry
+# credentials; `publishers:` supports per-entry `env:` instead, so
+# it's used to invoke scripts/upload-r2.sh once per artifact. Custom
+# publishers inherit almost nothing from the environment, hence the
+# explicit R2_* forwarding below.
+#
+# This publisher fires 109 times for 73 distinct keys because
+# goreleaser's release pipe already registers `release.extra_files`
+# as UploadableFile artifacts, and `internal/exec`'s filterArtifacts
+# appends this block's own extra_files with no de-duplication. It
+# can't be globbed away, since gobwas/glob (via goreleaser/fileglob)
+# has no substring-exclusion matcher. It's harmless: PUT is
+# idempotent, and the `./**.xz` glob below is kept deliberately so
+# this publisher declares its own complete file set rather than
+# implicitly depending on the `release:` block's globs.
+publishers:
+  - name: cloudflare-r2
+    checksum: true
+    extra_files:
+      - glob: ./**.xz
+      - glob: ./**.sha256
+    cmd: sh scripts/upload-r2.sh {{ abs .ArtifactPath }} gitea-runner/{{ .Version }}/{{ .ArtifactName }}
+    env:
+      - R2_ENDPOINT={{ index .Env "R2_ENDPOINT" }}
+      - R2_BUCKET={{ index .Env "R2_BUCKET" }}
+      - R2_ACCESS_KEY_ID={{ index .Env "R2_ACCESS_KEY_ID" }}
+      - R2_SECRET_ACCESS_KEY={{ index .Env "R2_SECRET_ACCESS_KEY" }}
+
 archives:
   - format: binary
     name_template: "{{ .Binary }}"

go.mod

@@ -28,7 +28,7 @@ require (
 	github.com/opencontainers/image-spec v1.1.1
 	github.com/opencontainers/selinux v1.15.1
 	github.com/pkg/errors v0.9.1
-	github.com/prometheus/client_golang v1.24.0
+	github.com/prometheus/client_golang v1.23.2
 	github.com/prometheus/client_model v0.6.2
 	github.com/rhysd/actionlint v1.7.12
 	github.com/sirupsen/logrus v1.9.4
@@ -73,7 +73,7 @@ require (
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99 // indirect
 	github.com/kevinburke/ssh_config v1.6.0 // indirect
-	github.com/klauspost/compress v1.19.0 // indirect
+	github.com/klauspost/compress v1.18.5 // indirect
 	github.com/klauspost/cpuid/v2 v2.3.0 // indirect
 	github.com/mattn/go-colorable v0.1.14 // indirect
 	github.com/mattn/go-runewidth v0.0.21 // indirect
@@ -86,8 +86,8 @@ require (
 	github.com/opencontainers/go-digest v1.0.0 // indirect
 	github.com/pjbgf/sha1cd v0.6.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/prometheus/common v0.70.0 // indirect
-	github.com/prometheus/procfs v0.21.1 // indirect
+	github.com/prometheus/common v0.66.1 // indirect
+	github.com/prometheus/procfs v0.17.0 // indirect
 	github.com/robfig/cron/v3 v3.0.1 // indirect
 	github.com/sergi/go-diff v1.4.0 // indirect
 	github.com/skeema/knownhosts v1.3.2 // indirect
@@ -103,10 +103,10 @@ require (
 	go.opentelemetry.io/otel/sdk v1.43.0 // indirect
 	go.opentelemetry.io/otel/sdk/metric v1.43.0 // indirect
 	go.opentelemetry.io/otel/trace v1.43.0 // indirect
-	go.yaml.in/yaml/v2 v2.4.4 // indirect
+	go.yaml.in/yaml/v2 v2.4.3 // indirect
 	go.yaml.in/yaml/v3 v3.0.4 // indirect
-	golang.org/x/crypto v0.53.0 // indirect
-	golang.org/x/net v0.56.0 // indirect
+	golang.org/x/crypto v0.52.0 // indirect
+	golang.org/x/net v0.54.0 // indirect
 	golang.org/x/sync v0.22.0 // indirect
 	gopkg.in/warnings.v0 v0.1.2 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect

go.sum

@@ -106,8 +106,6 @@ github.com/kevinburke/ssh_config v1.6.0 h1:J1FBfmuVosPHf5GRdltRLhPJtJpTlMdKTBjRg
 github.com/kevinburke/ssh_config v1.6.0/go.mod h1:q2RIzfka+BXARoNexmF9gkxEX7DmvbW9P4hIVx2Kg4M=
 github.com/klauspost/compress v1.18.5 h1:/h1gH5Ce+VWNLSWqPzOVn6XBO+vJbCNGvjoaGBFW2IE=
 github.com/klauspost/compress v1.18.5/go.mod h1:cwPg85FWrGar70rWktvGQj8/hthj3wpl0PGDogxkrSQ=
-github.com/klauspost/compress v1.19.0 h1:sXLILfc9jV2QYWkzFOPWStmcUVH2RHEB1JCdY2oVvCQ=
-github.com/klauspost/compress v1.19.0/go.mod h1:cwPg85FWrGar70rWktvGQj8/hthj3wpl0PGDogxkrSQ=
 github.com/klauspost/cpuid/v2 v2.3.0 h1:S4CRMLnYUhGeDFDqkGriYKdfoFlDnMtqTiI/sFzhA9Y=
 github.com/klauspost/cpuid/v2 v2.3.0/go.mod h1:hqwkgyIinND0mEev00jJYCxPNVRVXFQeu1XKlok6oO0=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
@@ -163,18 +161,12 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prometheus/client_golang v1.23.2 h1:Je96obch5RDVy3FDMndoUsjAhG5Edi49h0RJWRi/o0o=
 github.com/prometheus/client_golang v1.23.2/go.mod h1:Tb1a6LWHB3/SPIzCoaDXI4I8UHKeFTEQ1YCr+0Gyqmg=
-github.com/prometheus/client_golang v1.24.0 h1:5XStIklKuAtJSNpdD3s8XJj/Yv78IQmE1kbNk87JrAI=
-github.com/prometheus/client_golang v1.24.0/go.mod h1:QcsNdotprC2nS4BTM2ucbcqxd2CeXTEa9jW7zHO9iDE=
 github.com/prometheus/client_model v0.6.2 h1:oBsgwpGs7iVziMvrGhE53c/GrLUsZdHnqNwqPLxwZyk=
 github.com/prometheus/client_model v0.6.2/go.mod h1:y3m2F6Gdpfy6Ut/GBsUqTWZqCUvMVzSfMLjcu6wAwpE=
 github.com/prometheus/common v0.66.1 h1:h5E0h5/Y8niHc5DlaLlWLArTQI7tMrsfQjHV+d9ZoGs=
 github.com/prometheus/common v0.66.1/go.mod h1:gcaUsgf3KfRSwHY4dIMXLPV0K/Wg1oZ8+SbZk/HH/dA=
-github.com/prometheus/common v0.70.0 h1:bcpru3tWPVnxGnETLgOV5jbp/JRXgYEyv65CuBLAMMI=
-github.com/prometheus/common v0.70.0/go.mod h1:S/SFasQmgGiYH6C81LKCtYa8QACgthGg5zxL2udV7SY=
 github.com/prometheus/procfs v0.17.0 h1:FuLQ+05u4ZI+SS/w9+BWEM2TXiHKsUQ9TADiRH7DuK0=
 github.com/prometheus/procfs v0.17.0/go.mod h1:oPQLaDAMRbA+u8H5Pbfq+dl3VDAvHxMUOVhe0wYB2zw=
-github.com/prometheus/procfs v0.21.1 h1:GljZCt+zSTS+NZq88cyQ1LjZ+RCHp3uVuabBWA5+OJI=
-github.com/prometheus/procfs v0.21.1/go.mod h1:aB55Cww9pdSJVHk0hUf0inxWyyjPogFIjmHKYgMKmtY=
 github.com/rhysd/actionlint v1.7.12 h1:vQ4GeJN86C0QH+gTUQcs8McmK62OLT3kmakPMtEWYnY=
 github.com/rhysd/actionlint v1.7.12/go.mod h1:krOUhujIsJusovkaYzQ/VNH8PFexjNKqU0q5XI/4w+g=
 github.com/robfig/cron/v3 v3.0.1 h1:WdRxkvbJztn8LMz/QEvLN5sBU+xKpSqwwUO1Pjr4qDs=
@@ -240,7 +232,6 @@ go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
 go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
 go.yaml.in/yaml/v2 v2.4.3 h1:6gvOSjQoTB3vt1l+CU+tSyi/HOjfOjRLJ4YwYZGwRO0=
 go.yaml.in/yaml/v2 v2.4.3/go.mod h1:zSxWcmIDjOzPXpjlTTbAsKokqkDNAVtZO0WOMiT90s8=
-go.yaml.in/yaml/v2 v2.4.4/go.mod h1:gMZqIpDtDqOfM0uNfy0SkpRhvUryYH0Z6wdMYcacYXQ=
 go.yaml.in/yaml/v3 v3.0.4 h1:tfq32ie2Jv2UxXFdLJdh3jXuOzWiL1fo0bu/FbuKpbc=
 go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
 go.yaml.in/yaml/v4 v4.0.0-rc.3 h1:3h1fjsh1CTAPjW7q/EMe+C8shx5d8ctzZTrLcs/j8Go=
@@ -248,15 +239,11 @@ go.yaml.in/yaml/v4 v4.0.0-rc.3/go.mod h1:aZqd9kCMsGL7AuUv/m/PvWLdg5sjJsZ4oHDEnfP
 golang.org/x/crypto v0.0.0-20220622213112-05595931fe9d/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 golang.org/x/crypto v0.52.0 h1:RMs7fP2rXdep0CftQlK8Uf+kibLm7qkCcradZWYz988=
 golang.org/x/crypto v0.52.0/go.mod h1:1QgfPxDqh0T2M/elOJtp9RvuR95kVjir0e6/BvEmGbc=
-golang.org/x/crypto v0.53.0 h1:QZ4Muo8THX6CizN2vPPd5fBGHyogrdK9fG4wLPFUsto=
-golang.org/x/crypto v0.53.0/go.mod h1:DNLU434OwVakk9PzuwV8w62mAJpRJL3vsgcfp4Qnsio=
 golang.org/x/exp v0.0.0-20260410095643-746e56fc9e2f h1:W3F4c+6OLc6H2lb//N1q4WpJkhzJCK5J6kUi1NTVXfM=
 golang.org/x/exp v0.0.0-20260410095643-746e56fc9e2f/go.mod h1:J1xhfL/vlindoeF/aINzNzt2Bket5bjo9sdOYzOsU80=
 golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.54.0 h1:2zJIZAxAHV/OHCDTCOHAYehQzLfSXuf/5SoL/Dv6w/w=
 golang.org/x/net v0.54.0/go.mod h1:Sj4oj8jK6XmHpBZU/zWHw3BV3abl4Kvi+Ut7cQcY+cQ=
-golang.org/x/net v0.56.0 h1:Rw8j/hFzGvJUZwNBXnAtf5sVDVt+65SK2C7IxCxZt5o=
-golang.org/x/net v0.56.0/go.mod h1:D3Ku6r+V6JROoZK144D2XfMHFcMq/0zSfLelVTCFKec=
 golang.org/x/sync v0.20.0 h1:e0PTpb7pjO8GAtTs2dQ6jYa5BWYlMuX047Dco/pItO4=
 golang.org/x/sync v0.20.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0=
 golang.org/x/sync v0.22.0 h1:SZjpbeLmrCk4xhRSZFNZW5gFUeCeFgjekvI/+gfScek=

scripts/upload-r2.sh

@@ -0,0 +1,112 @@
+#!/bin/sh
+# Copyright 2026 The Gitea Authors. All rights reserved.
+# SPDX-License-Identifier: MIT
+#
+# upload-r2.sh uploads a single local file to a single object key in a
+# Cloudflare R2 bucket, using curl's built-in AWS SigV4 signer (R2 is
+# S3-API compatible).
+#
+# This is the R2 half of the release process's parallel S3+R2 upload
+# period: goreleaser's `blobs:` pipe still uploads every release
+# artifact to AWS S3, and this script is invoked once per artifact
+# (via a goreleaser `publishers:` entry) to mirror the same artifact
+# into R2. Once the migration away from S3 is complete, the `blobs:`
+# block and the AWS_* secrets can be dropped without touching this
+# script.
+#
+# Usage:
+#   upload-r2.sh <local-file> <remote-key>
+#   upload-r2.sh --check-config
+#
+# The second form only validates that the required environment
+# variables below are set (it does not touch the network or the
+# filesystem beyond that), and is meant to be run as an early
+# preflight step in CI: goreleaser custom publishers run as the very
+# last step of the publish pipeline, so without a preflight check a
+# missing R2_* secret would only be discovered after the Gitea release
+# has already been created and every artifact already uploaded to S3.
+#
+# Required environment variables:
+#   R2_ENDPOINT          Base URL of the R2 endpoint, e.g.
+#                        https://<account>.r2.cloudflarestorage.com
+#   R2_BUCKET            Destination bucket name.
+#   R2_ACCESS_KEY_ID     R2 access key id.
+#   R2_SECRET_ACCESS_KEY R2 secret access key.
+
+set -eu
+
+# check_env validates that all required R2_* environment variables are
+# set and non-empty, printing a single "missing required environment
+# variable(s): ..." message and exiting non-zero otherwise. Used by
+# both the normal upload mode and --check-config, so the validation
+# logic only exists in one place.
+check_env() {
+  missing=""
+
+  if [ -z "${R2_ENDPOINT:-}" ]; then
+    missing="$missing R2_ENDPOINT"
+  fi
+  if [ -z "${R2_BUCKET:-}" ]; then
+    missing="$missing R2_BUCKET"
+  fi
+  if [ -z "${R2_ACCESS_KEY_ID:-}" ]; then
+    missing="$missing R2_ACCESS_KEY_ID"
+  fi
+  if [ -z "${R2_SECRET_ACCESS_KEY:-}" ]; then
+    missing="$missing R2_SECRET_ACCESS_KEY"
+  fi
+
+  if [ -n "$missing" ]; then
+    echo "upload-r2.sh: missing required environment variable(s):$missing" >&2
+    exit 1
+  fi
+}
+
+if [ "$#" -eq 1 ] && [ "$1" = "--check-config" ]; then
+  check_env
+  echo "upload-r2.sh: R2 configuration OK"
+  exit 0
+fi
+
+if [ "$#" -ne 2 ]; then
+  echo "usage: upload-r2.sh <local-file> <remote-key>" >&2
+  echo "       upload-r2.sh --check-config" >&2
+  exit 1
+fi
+
+local_file="$1"
+remote_key="$2"
+
+if [ ! -f "$local_file" ]; then
+  echo "upload-r2.sh: local file not found: $local_file" >&2
+  exit 1
+fi
+
+check_env
+
+# Strip a single trailing slash from the endpoint, if present, so that
+# building the path-style URL below never produces a double slash.
+endpoint="${R2_ENDPOINT%/}"
+url="$endpoint/$R2_BUCKET/$remote_key"
+
+# Credentials are passed to curl through a config file read from
+# stdin rather than as a command-line argument, so they never show up
+# in `ps` output.
+#
+# --fail-with-body (instead of plain --fail) still exits non-zero on
+# HTTP errors, but also prints R2's XML error body, which is where the
+# actual error code lives (SignatureDoesNotMatch, NoSuchBucket,
+# AccessDenied, ...); with plain --fail that body is discarded and the
+# failure is silent. --retry 3 (without --retry-all-errors) still
+# retries the transient cases (5xx, 408, 429, connection failures);
+# --retry-all-errors would additionally retry permanent 4xx responses
+# three times with backoff, which only delays an inevitable failure.
+printf 'user = "%s:%s"\n' "$R2_ACCESS_KEY_ID" "$R2_SECRET_ACCESS_KEY" | curl \
+  --config - \
+  --fail-with-body \
+  --silent \
+  --show-error \
+  --retry 3 \
+  --aws-sigv4 "aws:amz:auto:s3" \
+  --upload-file "$local_file" \
+  "$url"