ci: document and script the release process (WebAssembly#295)

Previously, the release process for wasi-sdk was undocumented and
manual. The `RELEASING.md` document in this commit describes the steps
necessary to publish a new version of `wasi-sdk` as a GitHub release and
provides helpful scripts to automate some of the steps.

With this in place, a future change could add a workflow trigger that
allows running the steps automatically in GitHub actions. Keeping the
steps as scripts in the repository, however, allows developers to re-run
steps themselves in the (likely) case that something goes awry.

README.md

@@ -38,22 +38,24 @@ The Wasm-sdk's build process needs some packages :
 * `clang`
 * `ninja`
 
-Please refer to your OS documentation to install those packages. 
+Please refer to your OS documentation to install those packages.
 
-## Build 
+## Build
 
-To build the full package
+To build the full package:
 
 ```shell script
 cd wasi-sdk
 NINJA_FLAGS=-v make package
 ```
 
-The built package can be found into `dist` directory.
+The built package can be found into `dist` directory. For releasing a new
+version of the package on GitHub, see [RELEASING.md](RELEASING.md).
 
 ## Install
 
 A typical installation from the release binaries might look like the following:
+
 ```shell script
 export WASI_VERSION=14
 export WASI_VERSION_FULL=${WASI_VERSION}.0
@@ -64,13 +66,16 @@ tar xvf wasi-sdk-${WASI_VERSION_FULL}-linux.tar.gz
 ## Use
 
 Use the clang installed in the wasi-sdk directory:
+
 ```shell script
 export WASI_SDK_PATH=`pwd`/wasi-sdk-${WASI_VERSION_FULL}
 CC="${WASI_SDK_PATH}/bin/clang --sysroot=${WASI_SDK_PATH}/share/wasi-sysroot"
 $CC foo.c -o foo.wasm
 ```
-Note: `${WASI_SDK_PATH}/share/wasi-sysroot` contains the WASI-specific includes/libraries/etc. The `--sysroot=...` option
-is not necessary if `WASI_SDK_PATH` is `/opt/wasi-sdk`.
+
+Note: `${WASI_SDK_PATH}/share/wasi-sysroot` contains the WASI-specific
+includes/libraries/etc. The `--sysroot=...` option is not necessary if
+`WASI_SDK_PATH` is `/opt/wasi-sdk`.
 
 ## Notes for Autoconf
 
@@ -104,7 +109,7 @@ disabled in a configure step before building with wasi-sdk.
 
 This repository does not yet support C++ exceptions. C++ code is
 supported only with -fno-exceptions for now. Similarly, there is not
-yet support for setjmp/longjmp. Work on support for [exception handling] 
+yet support for setjmp/longjmp. Work on support for [exception handling]
 is underway at the language level which will support both of these
 features.
 

RELEASING.md

@@ -0,0 +1,48 @@
+# Release Process
+
+To publish a new version of `wasi-sdk` as a GitHub release:
+
+1. Tag a commit with an annotated tag. Note that this must be an annotated tag,
+   not a lightweight tag, so that `version.sh` can use it for calculating the
+   package version (use `git show wasi-sdk-...` to show other tag messages).
+
+   ```shell script
+   TAG=wasi-sdk-1
+   git tag -a $TAG
+   git push origin $TAG
+   ```
+
+2. Find a successful workflow that CI has run for the tag. That successful
+   workflow run will have build artifacts that need to be attached to the
+   release. One could search around in the GitHub [actions], but the following
+   script will list completed workflows for a tag (get a token [here][tokens]):
+
+   ```shell script
+   ci/get-workflows-for-tag.sh $TAG $GITHUB_TOKEN
+   ```
+
+   [actions]: https://github.com/WebAssembly/wasi-sdk/actions
+   [tokens]: https://github.com/settings/tokens
+
+3. Download and unzip the workflow artifacts. Note that artifacts with `+m` or
+   `.m` suffixes indicate that the Git tree was modified. Expect some duplicates
+   since some of the same artifacts are built on multiple CI runners (e.g.,
+   Windows, MacOS, Linux). The following script does all of this automatically:
+
+   ```shell script
+   ci/download-workflow-artifacts.sh $TAG $WORKFLOW_RUN_ID $GITHUB_TOKEN
+   ```
+
+4. Draft a new release. This could be done [manually][releases] but the
+   following script simplifies the uploading of all the files and auto-generates
+   the release description:
+
+  ```shell script
+  ci/draft-release.sh $TAG $ARTIFACTS_DIR $GITHUB_TOKEN
+  ```
+
+  [releases]: https://github.com/WebAssembly/wasi-sdk/releases
+
+5. Publish the release; the previous step only creates a draft. Follow the link
+   in the previous step or navigate to the GitHub [releases] to review the
+   description, commit, tag, and assets before clicking "Publish"

ci/download-workflow-artifacts.sh

@@ -0,0 +1,102 @@
+#!/usr/bin/env bash
+set -e
+
+# This script downloads and unzips the artifacts produced in a workflow run. It
+# also checks that the workflow commit corresponds to the tag commit that these
+# artifacts will be released under. The script has several pre-requisites:
+# - some standard Bash tools (curl, unzip) and one slightly more rare one (jq)
+# - an already-created tag in the repository (this marks the code to release)
+# - the ID of a workflow run that has run successfully--this is where we
+#   retrieve the artifacts from
+# - a GitHub access token, see https://github.com/settings/tokens
+#
+# Usage: download-workflow-artifacts.sh <release tag> <workflow run ID> <token>
+
+TAG=$1
+WORKFLOW_RUN_ID=$2
+GITHUB_TOKEN=$3
+GITHUB_API_VERSION=2022-11-28
+GITHUB_API_URL=https://api.github.com/repos/WebAssembly/wasi-sdk
+TMP_DIR=$(mktemp -d -t wasi-sdk-artifacts.XXXXXXX)
+
+if [ -z "${TAG}" ] || [ -z "${WORKFLOW_RUN_ID}" ] || [ -z "${GITHUB_TOKEN}" ]; then
+    >&2 echo "Missing parameter; exiting..."
+    >&2 echo "Usage: download-worfklow-artifacts.sh <release tag> <workflow run ID> <token>"
+    exit 1
+fi
+
+# Get the commit SHA for the passed tag.
+# See https://docs.github.com/en/rest/commits/commits#get-a-commit
+MATCHING_COMMIT=$(curl \
+    -H "Accept: application/vnd.github+json" \
+    -H "Authorization: Bearer ${GITHUB_TOKEN}" \
+    -H "X-GitHub-Api-Version: ${GITHUB_API_VERSION}" \
+    "${GITHUB_API_URL}/commits/${TAG}")
+COMMIT=$(echo $MATCHING_COMMIT  | jq -r '.sha')
+>&2 echo "===== Found commit for tag ${TAG}: ${COMMIT} ====="
+
+# Check that the commit of the workflow run matches the tag commit and that the
+# workflow was successful.
+# See https://docs.github.com/en/rest/actions/workflow-runs#get-a-workflow-run
+WORKFLOW_RUN=$(curl \
+    -H "Accept: application/vnd.github+json" \
+    -H "Authorization: Bearer ${GITHUB_TOKEN}" \
+    -H "X-GitHub-Api-Version: ${GITHUB_API_VERSION}" \
+    "${GITHUB_API_URL}/actions/runs/${WORKFLOW_RUN_ID}")
+WORKFLOW_COMMIT=$(echo $WORKFLOW_RUN | jq -r '.head_sha')
+WORKFLOW_STATUS=$(echo $WORKFLOW_RUN | jq -r '.status')
+>&2 echo "===== Found commit for workflow ${WORKFLOW_RUN_ID}: ${WORKFLOW_COMMIT} ====="
+if [ "${COMMIT}" != "${WORKFLOW_COMMIT}" ]; then
+    >&2 echo "Commit at tag ${TAG} did not match the commit for workflow ${WORKFLOW_RUN_ID}, exiting...:"
+    >&2 echo "  ${COMMIT} != ${WORKFLOW_COMMIT}"
+    exit 1
+fi
+if [ "${WORKFLOW_STATUS}" != "completed" ]; then
+    >&2 echo "Workflow ${WORKFLOW_RUN_ID} did not end successfully, exiting...:"
+    >&2 echo "  status = ${WORKFLOW_STATUS}"
+    exit 1
+fi
+
+# List out the artifacts in the given workflow run.
+# See https://docs.github.com/en/rest/actions/artifacts#list-workflow-run-artifacts
+ARTIFACTS=$(curl \
+    -H "Accept: application/vnd.github+json" \
+    -H "Authorization: Bearer ${GITHUB_TOKEN}" \
+    -H "X-GitHub-Api-Version: ${GITHUB_API_VERSION}" \
+    "${GITHUB_API_URL}/actions/runs/${WORKFLOW_RUN_ID}/artifacts" \
+        | jq -r '.artifacts[] | [(.id|tostring), .name, .archive_download_url] | join(",")')
+
+for A in $ARTIFACTS; do
+    ID=$(echo $A | cut -d ',' -f 1)
+    NAME=$(echo $A | cut -d ',' -f 2)
+    URL=$(echo $A | cut -d ',' -f 3)
+    TO=$TMP_DIR/$NAME.zip
+    >&2 echo "===== Downloading: ${TO} ====="
+
+    # Download the artifacts to the temporary directory.
+    # See https://docs.github.com/en/rest/actions/artifacts#download-an-artifact
+    curl \
+        -H "Accept: application/vnd.github+json" \
+        -H "Authorization: Bearer ${GITHUB_TOKEN}" \
+        -H "X-GitHub-Api-Version: ${GITHUB_API_VERSION}" \
+        --location --output "${TO}" \
+        "${GITHUB_API_URL}/actions/artifacts/${ID}/zip"
+done
+
+# Unzip the workflow artifacts into a `release` directory.
+pushd $TMP_DIR > /dev/null
+mkdir release
+ls -1 *.zip | xargs -n1 unzip -q -o -d release
+# Some explanation:
+#   -1 prints each file on a separate line
+#   -n1 runs the command once for each item
+#   -q means quietly
+#   -o allows unzip to overwrite existing files (e.g., multiple copies of `libclang_rt.builtins-wasm32-wasi-...`)
+#   -d tells unzip which directory to place things in
+>&2 echo "===== Files to release: ${TMP_DIR}/release ====="
+>&2 ls -1 release
+popd > /dev/null
+
+>&2 echo
+>&2 echo "Ensure the above artifacts look correct, then run \`draft-release.sh\` with the following directory:"
+echo "${TMP_DIR}/release"

ci/draft-release.sh

@@ -0,0 +1,71 @@
+#!/usr/bin/env bash
+set -e
+
+# This script creates a draft pre-release with the artifacts produced in a
+# workflow run (see `download-workflow-artifacts.sh`). Note that the pre-release
+# is not published publicly--this is kept as a manual step as a safeguard. The
+# script has several pre-requisites:
+# - some standard Bash tools (curl, unzip) and one slightly more rare one (jq)
+# - an already-created tag in the repository (this marks the code to release)
+# - a directory containing the artifacts to attach to the release.
+# - a GitHub access token, see https://github.com/settings/tokens
+#
+# Usage: draft-release.sh <release tag> <artifacts dir> <token>
+
+TAG=$1
+ARTIFACTS_DIR=$2
+GITHUB_TOKEN=$3
+GITHUB_API_VERSION=2022-11-28
+GITHUB_API_URL=https://api.github.com/repos/WebAssembly/wasi-sdk
+TMP_DIR=$(mktemp -d -t release.sh.XXXXXXX)
+
+if [ -z "${TAG}" ] || [ -z "${ARTIFACTS_DIR}" ] || [ -z "${GITHUB_TOKEN}" ]; then
+    >&2 echo "Missing parameter; exiting..."
+    >&2 echo "Usage: draft-release.sh <release tag> <artifacts dir> <token>"
+    exit 1
+fi
+
+# Get the commit SHA for the passed tag.
+# See https://docs.github.com/en/rest/commits/commits#get-a-commit
+MATCHING_COMMIT=$(curl \
+    -H "Accept: application/vnd.github+json" \
+    -H "Authorization: Bearer ${GITHUB_TOKEN}" \
+    -H "X-GitHub-Api-Version: ${GITHUB_API_VERSION}" \
+    "${GITHUB_API_URL}/commits/${TAG}")
+COMMIT=$(echo $MATCHING_COMMIT  | jq -r '.sha')
+>&2 echo "===== Found commit for tag ${TAG}: ${COMMIT} ====="
+
+# Create a draft pre-release for this commit.
+# See https://docs.github.com/en/rest/releases/releases#create-a-release
+RELEASE_JSON=$(curl \
+    -X POST \
+    -H "Accept: application/vnd.github+json" \
+    -H "Authorization: Bearer ${GITHUB_TOKEN}"\
+    -H "X-GitHub-Api-Version: ${GITHUB_API_VERSION}" \
+    "${GITHUB_API_URL}/releases" \
+    -d '{"tag_name":"'${TAG}'","target_commitish":"'${COMMIT}'","name":"'${TAG}'","draft":true,"prerelease":true,"generate_release_notes":true}')
+UPLOAD_URL=$(echo $RELEASE_JSON | jq -r '.upload_url')
+# Remove the "helpful" but invalid URL suffix that GitHub adds:
+UPLOAD_URL=${UPLOAD_URL/\{?name,label\}}
+HTML_URL=$(echo $RELEASE_JSON | jq -r '.html_url')
+>&2 echo "===== Created draft release: ${HTML_URL} ====="
+
+# Upload the unzipped artifact files to the release.
+# See https://docs.github.com/en/rest/releases/assets#upload-a-release-asset
+for FILE in $(ls "${ARTIFACTS_DIR}"); do
+    FROM=$ARTIFACTS_DIR/$FILE
+    >&2 echo "===== Uploading: ${FROM} ====="
+    UPLOADED=$(curl \
+        -X POST \
+        -H "Accept: application/vnd.github+json" \
+        -H "Authorization: Bearer ${GITHUB_TOKEN}"\
+        -H "X-GitHub-Api-Version: ${GITHUB_API_VERSION}" \
+        -H "Content-Type: application/octet-stream" \
+        "${UPLOAD_URL}?name=${FILE}" \
+        --data-binary "@${FROM}")
+done
+
+>&2 echo
+>&2 echo "===== Completed ====="
+>&2 echo "This created a draft release, do not forget to manually publish it at:"
+echo "${HTML_URL}"

ci/get-workflows-for-tag.sh

@@ -0,0 +1,43 @@
+#!/usr/bin/env bash
+set -e
+
+# This script retrieves a list of GitHub workflow runs that have successfully completed for a given
+# Git tag. The list is printed to stdout (all other output to stderr). It has several
+# pre-requisites:
+# - some standard Bash tools (curl) and one slightly more rare one (jq)
+# - an already-created tag in the repository (this marks the code to release)
+# - a GitHub access token, see https://github.com/settings/tokens
+#
+# Usage: get-workflows-for-tag.sh <tag> <token>
+
+TAG=$1
+GITHUB_TOKEN=$2
+GITHUB_API_VERSION=2022-11-28
+GITHUB_API_URL=https://api.github.com/repos/WebAssembly/wasi-sdk
+
+if [ -z "${TAG}" ] || [ -z "${GITHUB_TOKEN}" ]; then
+    >&2 echo "Missing parameter; exiting..."
+    >&2 echo "Usage: get-workflows-for-tag.sh <tag> <token>"
+    exit 1
+fi
+
+# Get the commit SHA for the passed tag.
+# See https://docs.github.com/en/rest/commits/commits#get-a-commit
+MATCHING_COMMIT=$(curl \
+    -H "Accept: application/vnd.github+json" \
+    -H "Authorization: Bearer ${GITHUB_TOKEN}" \
+    -H "X-GitHub-Api-Version: ${GITHUB_API_VERSION}" \
+    "${GITHUB_API_URL}/commits/${TAG}")
+COMMIT=$(echo $MATCHING_COMMIT  | jq -r '.sha')
+>&2 echo "===== Found commit for tag ${TAG}: ${COMMIT} ====="
+
+# Find the workflow runs matching the tag commit.
+# See https://docs.github.com/en/rest/actions/workflow-runs#list-workflow-runs-for-a-repository
+MATCHING_WORKFLOWS=$(curl \
+    -H "Accept: application/vnd.github+json" \
+    -H "Authorization: Bearer ${GITHUB_TOKEN}" \
+    -H "X-GitHub-Api-Version: ${GITHUB_API_VERSION}" \
+    "${GITHUB_API_URL}/actions/runs?head_sha=${COMMIT}&status=success")
+WORKFLOW_RUN_IDS=$(echo $MATCHING_WORKFLOWS | jq -r '.workflow_runs[].id')
+>&2 echo "===== Matching workflow run IDs: ====="
+echo "$WORKFLOW_RUN_IDS"