From 5af3b45fbe2d8f9809ea5f92efa68b1d20bd5793 Mon Sep 17 00:00:00 2001
From: Eric Huss <eric@huss.org>
Date: Wed, 8 Jul 2026 21:39:07 -0700
Subject: [PATCH] Use REST API in linkchecker script

This changes the linkchecker script to use the REST API instead of the
raw endpoint to better deal with rate limits. We've noticed some
occasional times when GitHub Actions hits the rate limit. I believe the
raw http interface uses IP-based rate limits. On GitHub Actions, you're
at the mercy of when other users exhaust the rate limit for the IP your
job happens to grab. I believe this should help.

This will require updating the repos that use this script in order to
benefit. This should be backwards compatible, though.
---
 src/tools/linkchecker/linkcheck.sh | 33 +++++++++++++++++++++++++-----
 1 file changed, 28 insertions(+), 5 deletions(-)

diff --git a/src/tools/linkchecker/linkcheck.sh b/src/tools/linkchecker/linkcheck.sh
index d230610a6e79d..36c14d31d7310 100755
--- a/src/tools/linkchecker/linkcheck.sh
+++ b/src/tools/linkchecker/linkcheck.sh
@@ -23,6 +23,31 @@
 
 set -e
 
+# Fetches the contents of a file from GitHub using the REST API.
+# Usage: fetch_github_file OWNER REPO PATH OUTPUT_PATH
+fetch_github_file() {
+    owner="$1"
+    repo="$2"
+    path="$3"
+    output="$4"
+
+    # Hack to repurpose the function's positional parameters to conditionally
+    # pass curl headers. The GITHUB_TOKEN should be set to help avoid rate
+    # limits.
+    if [ -n "${GITHUB_TOKEN:-}" ]
+    then
+        set -- -H "Authorization: Bearer $GITHUB_TOKEN"
+    else
+        set --
+    fi
+
+    curl -L -o "$output" \
+        -H "Accept: application/vnd.github.raw" \
+        "$@" \
+        -H "X-GitHub-Api-Version: 2026-03-10" \
+        "https://api.github.com/repos/$owner/$repo/contents/$path"
+}
+
 html_dir="$(rustc +nightly --print sysroot)/share/doc/rust/html"
 
 if [ ! -d "$html_dir" ]
@@ -95,12 +120,10 @@ fi
 if [ ! -e "linkchecker/main.rs" ] || [ "$iterative" = "0" ]
 then
     echo "Downloading linkchecker source..."
-    nightly_hash=$(rustc +nightly -Vv | grep commit-hash | cut -f2 -d" ")
-    url="https://raw.githubusercontent.com/rust-lang/rust"
     mkdir linkchecker
-    curl -o linkchecker/Cargo.lock ${url}/${nightly_hash}/Cargo.lock
-    curl -o linkchecker/Cargo.toml ${url}/${nightly_hash}/src/tools/linkchecker/Cargo.toml
-    curl -o linkchecker/main.rs ${url}/${nightly_hash}/src/tools/linkchecker/main.rs
+    fetch_github_file rust-lang rust Cargo.lock linkchecker/Cargo.lock
+    fetch_github_file rust-lang rust src/tools/linkchecker/Cargo.toml linkchecker/Cargo.toml
+    fetch_github_file rust-lang rust src/tools/linkchecker/main.rs linkchecker/main.rs
 fi
 
 echo "Building book \"$book_name\"..."