nixpkgs/pkgs/build-support/fetchgit/nix-prefetch-git
Tim Cuthbertson 911aa1440f treewide: support NIX_SSL_CERT_FILE as an impureEnvVar
This envvar is also added to lib.proxyImpureEnvVars since it's
typically required for https proxies.

This change also updates fetchgit and go module fetching to use this
envvar. NIX_GIT_SSL_CAINFO is still supported for backwards
compatibility in fetchgit.
2024-08-23 21:34:22 +10:00

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#! /usr/bin/env bash
set -e -o pipefail
url=
rev=
expHash=
hashType=$NIX_HASH_ALGO
deepClone=$NIX_PREFETCH_GIT_DEEP_CLONE
leaveDotGit=$NIX_PREFETCH_GIT_LEAVE_DOT_GIT
fetchSubmodules=
fetchLFS=
builder=
branchName=$NIX_PREFETCH_GIT_BRANCH_NAME
# ENV params
out=${out:-}
http_proxy=${http_proxy:-}
# NOTE: use of NIX_GIT_SSL_CAINFO is for backwards compatibility; NIX_SSL_CERT_FILE is preferred
# as of PR#303307
GIT_SSL_CAINFO=${NIX_GIT_SSL_CAINFO:-$NIX_SSL_CERT_FILE}
# populated by clone_user_rev()
fullRev=
humanReadableRev=
commitDate=
commitDateStrict8601=
if test -n "$deepClone"; then
deepClone=true
else
deepClone=
fi
if test "$leaveDotGit" != 1; then
leaveDotGit=
else
leaveDotGit=true
fi
usage(){
echo >&2 "syntax: nix-prefetch-git [options] [URL [REVISION [EXPECTED-HASH]]]
Options:
--out path Path where the output would be stored.
--url url Any url understood by 'git clone'.
--rev ref Any sha1 or references (such as refs/heads/master)
--hash h Expected hash.
--branch-name Branch name to check out into
--sparse-checkout Only fetch and checkout part of the repository.
--non-cone-mode Use non-cone mode for sparse checkouts.
--deepClone Clone the entire repository.
--no-deepClone Make a shallow clone of just the required ref.
--leave-dotGit Keep the .git directories.
--fetch-lfs Fetch git Large File Storage (LFS) files.
--fetch-submodules Fetch submodules.
--builder Clone as fetchgit does, but url, rev, and out option are mandatory.
--quiet Only print the final json summary.
"
exit 1
}
# some git commands print to stdout, which would contaminate our JSON output
clean_git(){
git "$@" >&2
}
argi=0
argfun=""
for arg; do
if test -z "$argfun"; then
case $arg in
--out) argfun=set_out;;
--url) argfun=set_url;;
--rev) argfun=set_rev;;
--hash) argfun=set_hashType;;
--branch-name) argfun=set_branchName;;
--deepClone) deepClone=true;;
--sparse-checkout) argfun=set_sparseCheckout;;
--non-cone-mode) nonConeMode=true;;
--quiet) QUIET=true;;
--no-deepClone) deepClone=;;
--leave-dotGit) leaveDotGit=true;;
--fetch-lfs) fetchLFS=true;;
--fetch-submodules) fetchSubmodules=true;;
--builder) builder=true;;
-h|--help) usage; exit;;
*)
: $((++argi))
case $argi in
1) url=$arg;;
2) rev=$arg;;
3) expHash=$arg;;
*) exit 1;;
esac
;;
esac
else
case $argfun in
set_*)
var=${argfun#set_}
eval "$var=$(printf %q "$arg")"
;;
esac
argfun=""
fi
done
if test -z "$url"; then
usage
fi
init_remote(){
local url=$1
clean_git init --initial-branch=master
clean_git remote add origin "$url"
if [ -n "$sparseCheckout" ]; then
git config remote.origin.partialclonefilter "blob:none"
echo "$sparseCheckout" | git sparse-checkout set --stdin ${nonConeMode:+--no-cone}
fi
( [ -n "$http_proxy" ] && clean_git config --global http.proxy "$http_proxy" ) || true
}
# Return the reference of an hash if it exists on the remote repository.
ref_from_hash(){
local hash=$1
git ls-remote origin | sed -n "\,$hash\t, { s,\(.*\)\t\(.*\),\2,; p; q}"
}
# Return the hash of a reference if it exists on the remote repository.
hash_from_ref(){
local ref=$1
git ls-remote origin | sed -n "\,\t$ref, { s,\(.*\)\t\(.*\),\1,; p; q}"
}
# Returns a name based on the url and reference
#
# This function needs to be in sync with nix's fetchgit implementation
# of urlToName() to re-use the same nix store paths.
url_to_name(){
local url=$1
local ref=$2
local base
base=$(basename "$url" .git | cut -d: -f2)
if [[ $ref =~ ^[a-z0-9]+$ ]]; then
echo "$base-${ref:0:7}"
else
echo "$base"
fi
}
# Fetch and checkout the right sha1
checkout_hash(){
local hash="$1"
local ref="$2"
if test -z "$hash"; then
hash=$(hash_from_ref "$ref")
fi
[[ -z "$deepClone" ]] && \
clean_git fetch ${builder:+--progress} --depth=1 origin "$hash" || \
clean_git fetch -t ${builder:+--progress} origin || return 1
local object_type=$(git cat-file -t "$hash")
if [[ "$object_type" == "commit" || "$object_type" == "tag" ]]; then
clean_git checkout -b "$branchName" "$hash" || return 1
elif [[ "$object_type" == "tree" ]]; then
clean_git config user.email "nix-prefetch-git@localhost"
clean_git config user.name "nix-prefetch-git"
local commit_id=$(git commit-tree "$hash" -m "Commit created from tree hash $hash")
clean_git checkout -b "$branchName" "$commit_id" || return 1
else
echo "Unrecognized git object type: $object_type"
return 1
fi
}
# Fetch only a branch/tag and checkout it.
checkout_ref(){
local hash="$1"
local ref="$2"
if [[ -n "$deepClone" ]]; then
# The caller explicitly asked for a deep clone. Deep clones
# allow "git describe" and similar tools to work. See
# https://marc.info/?l=nix-dev&m=139641582514772
# for a discussion.
return 1
fi
if test -z "$ref"; then
ref=$(ref_from_hash "$hash")
fi
if test -n "$ref"; then
# --depth option is ignored on http repository.
clean_git fetch ${builder:+--progress} --depth 1 origin +"$ref" || return 1
clean_git checkout -b "$branchName" FETCH_HEAD || return 1
else
return 1
fi
}
# Update submodules
init_submodules(){
# shallow with leaveDotGit will change hashes
[[ -z "$deepClone" ]] && [[ -z "$leaveDotGit" ]] && \
clean_git submodule update --init --recursive -j ${NIX_BUILD_CORES:-1} --progress --depth 1 || \
clean_git submodule update --init --recursive -j ${NIX_BUILD_CORES:-1} --progress
}
clone(){
local top=$PWD
local dir="$1"
local url="$2"
local hash="$3"
local ref="$4"
cd "$dir"
# Initialize the repository.
init_remote "$url"
# Download data from the repository.
checkout_ref "$hash" "$ref" ||
checkout_hash "$hash" "$ref" || (
echo 1>&2 "Unable to checkout $hash$ref from $url."
exit 1
)
# Checkout linked sources.
if test -n "$fetchSubmodules"; then
init_submodules
fi
if [ -z "$builder" ] && [ -f .topdeps ]; then
if tg help &>/dev/null; then
echo "populating TopGit branches..."
tg remote --populate origin
else
echo "WARNING: would populate TopGit branches but TopGit is not available" >&2
echo "WARNING: install TopGit to fix the problem" >&2
fi
fi
cd "$top"
}
# Remove all remote branches, remove tags not reachable from HEAD, do a full
# repack and then garbage collect unreferenced objects.
make_deterministic_repo(){
local repo="$1"
# run in sub-shell to not touch current working directory
(
cd "$repo"
# Remove files that contain timestamps or otherwise have non-deterministic
# properties.
if [ -f .git ]; then
local dotgit_content=$(<.git)
local dotgit_dir="${dotgit_content#gitdir: }"
else
local dotgit_dir=".git"
fi
pushd "$dotgit_dir" >/dev/null
rm -rf logs/ hooks/ index FETCH_HEAD ORIG_HEAD refs/remotes/origin/HEAD config
popd >/dev/null
# Remove all remote branches.
git branch -r | while read -r branch; do
clean_git branch -rD "$branch"
done
# Remove tags not reachable from HEAD. If we're exactly on a tag, don't
# delete it.
maybe_tag=$(git tag --points-at HEAD)
git tag --contains HEAD | while read -r tag; do
if [ "$tag" != "$maybe_tag" ]; then
clean_git tag -d "$tag"
fi
done
# Do a full repack. Must run single-threaded, or else we lose determinism.
clean_git config pack.threads 1
clean_git repack -A -d -f
rm -f "$dotgit_dir/config"
# Garbage collect unreferenced objects.
# Note: --keep-largest-pack prevents non-deterministic ordering of packs
# listed in .git/objects/info/packs by only using a single pack
clean_git gc --prune=all --keep-largest-pack
)
}
clone_user_rev() {
local dir="$1"
local url="$2"
local rev="${3:-HEAD}"
if [ -n "$fetchLFS" ]; then
clean_git lfs install
fi
# Perform the checkout.
case "$rev" in
HEAD|refs/*)
clone "$dir" "$url" "" "$rev" 1>&2;;
*)
if test -z "$(echo "$rev" | tr -d 0123456789abcdef)"; then
clone "$dir" "$url" "$rev" "" 1>&2
else
# if revision is not hexadecimal it might be a tag
clone "$dir" "$url" "" "refs/tags/$rev" 1>&2
fi;;
esac
pushd "$dir" >/dev/null
fullRev=$( (git rev-parse "$rev" 2>/dev/null || git rev-parse "refs/heads/$branchName") | tail -n1)
humanReadableRev=$(git describe "$fullRev" 2> /dev/null || git describe --tags "$fullRev" 2> /dev/null || echo -- none --)
commitDate=$(git show -1 --no-patch --pretty=%ci "$fullRev")
commitDateStrict8601=$(git show -1 --no-patch --pretty=%cI "$fullRev")
popd >/dev/null
# Allow doing additional processing before .git removal
eval "$NIX_PREFETCH_GIT_CHECKOUT_HOOK"
if test -z "$leaveDotGit"; then
echo "removing \`.git'..." >&2
find "$dir" -name .git -print0 | xargs -0 rm -rf
else
find "$dir" -name .git | while read -r gitdir; do
make_deterministic_repo "$(readlink -f "$(dirname "$gitdir")")"
done
fi
}
exit_handlers=()
run_exit_handlers() {
exit_status=$?
for handler in "${exit_handlers[@]}"; do
eval "$handler $exit_status"
done
}
trap run_exit_handlers EXIT
quiet_exit_handler() {
exec 2>&3 3>&-
if [ $1 -ne 0 ]; then
cat "$errfile" >&2
fi
rm -f "$errfile"
}
quiet_mode() {
errfile="$(mktemp "${TMPDIR:-/tmp}/git-checkout-err-XXXXXXXX")"
exit_handlers+=(quiet_exit_handler)
exec 3>&2 2>"$errfile"
}
json_escape() {
local s="$1"
s="${s//\\/\\\\}" # \
s="${s//\"/\\\"}" # "
s="${s//^H/\\\b}" # \b (backspace)
s="${s//^L/\\\f}" # \f (form feed)
s="${s//
/\\\n}" # \n (newline)
s="${s//^M/\\\r}" # \r (carriage return)
s="${s// /\\t}" # \t (tab)
echo "$s"
}
print_results() {
hash="$1"
if ! test -n "$QUIET"; then
echo "" >&2
echo "git revision is $fullRev" >&2
if test -n "$finalPath"; then
echo "path is $finalPath" >&2
fi
echo "git human-readable version is $humanReadableRev" >&2
echo "Commit date is $commitDate" >&2
if test -n "$hash"; then
echo "hash is $hash" >&2
fi
fi
if test -n "$hash"; then
cat <<EOF
{
"url": "$(json_escape "$url")",
"rev": "$(json_escape "$fullRev")",
"date": "$(json_escape "$commitDateStrict8601")",
"path": "$(json_escape "$finalPath")",
"$(json_escape "$hashType")": "$(json_escape "$hash")",
"hash": "$(nix-hash --to-sri --type $hashType $hash)",
"fetchLFS": $([[ -n "$fetchLFS" ]] && echo true || echo false),
"fetchSubmodules": $([[ -n "$fetchSubmodules" ]] && echo true || echo false),
"deepClone": $([[ -n "$deepClone" ]] && echo true || echo false),
"leaveDotGit": $([[ -n "$leaveDotGit" ]] && echo true || echo false)
}
EOF
fi
}
remove_tmpPath() {
rm -rf "$tmpPath"
}
remove_tmpHomePath() {
rm -rf "$tmpHomePath"
}
if test -n "$QUIET"; then
quiet_mode
fi
if test -z "$branchName"; then
branchName=fetchgit
fi
tmpHomePath="$(mktemp -d "${TMPDIR:-/tmp}/nix-prefetch-git-tmp-home-XXXXXXXXXX")"
exit_handlers+=(remove_tmpHomePath)
ln -s "${NETRC:-$HOME/.netrc}" "$tmpHomePath/.netrc"
HOME="$tmpHomePath"
unset XDG_CONFIG_HOME
export GIT_CONFIG_NOSYSTEM=1
if test -n "$builder"; then
test -n "$out" -a -n "$url" -a -n "$rev" || usage
mkdir -p "$out"
clone_user_rev "$out" "$url" "$rev"
else
if test -z "$hashType"; then
hashType=sha256
fi
# If the hash was given, a file with that hash may already be in the
# store.
if test -n "$expHash"; then
finalPath=$(nix-store --print-fixed-path --recursive "$hashType" "$expHash" "$(url_to_name "$url" "$rev")")
if ! nix-store --check-validity "$finalPath" 2> /dev/null; then
finalPath=
fi
hash=$expHash
fi
# If we don't know the hash or a path with that hash doesn't exist,
# download the file and add it to the store.
if test -z "$finalPath"; then
tmpPath="$(mktemp -d "${TMPDIR:-/tmp}/git-checkout-tmp-XXXXXXXX")"
exit_handlers+=(remove_tmpPath)
tmpFile="$tmpPath/$(url_to_name "$url" "$rev")"
mkdir -p "$tmpFile"
# Perform the checkout.
clone_user_rev "$tmpFile" "$url" "$rev"
# Compute the hash.
hash=$(nix-hash --type $hashType --base32 "$tmpFile")
# Add the downloaded file to the Nix store.
finalPath=$(nix-store --add-fixed --recursive "$hashType" "$tmpFile")
if test -n "$expHash" -a "$expHash" != "$hash"; then
echo "hash mismatch for URL \`$url'. Got \`$hash'; expected \`$expHash'." >&2
exit 1
fi
fi
print_results "$hash"
if test -n "$PRINT_PATH"; then
echo "$finalPath"
fi
fi