Slim template render context interface

3 files changed, 170 insertions, 62 deletions

diff --git a/bin/photoalbum b/bin/photoalbum
index 7079465..cb629bb 100755
--- a/bin/photoalbum
+++ b/bin/photoalbum
@@ -576,38 +576,23 @@ validate_template_context() {
 source_template_file() {
     local -r template_path="$1"; shift
     local -r output_path="$1"; shift
+    local context_file
+    local -i status=0
+
+    context_file=$(mktemp)
+    {
+        serialize_template_render_context
+        printf 'unset BASH_ENV\n'
+    } > "$context_file"
 
-    env -i \
-        PATH="$PATH" \
-        render_animation_class_html="$render_animation_class_html" \
-        render_backhref_css="$render_backhref_css" \
-        render_backhref_html="$render_backhref_html" \
-        render_background_image_css="$render_background_image_css" \
-        render_blurs_dir_css="$render_blurs_dir_css" \
-        render_current_date_text="$render_current_date_text" \
-        render_enter_page_html="$render_enter_page_html" \
-        render_exif_details_html="$render_exif_details_html" \
-        render_height_html="$render_height_html" \
-        render_html_dir_html="$render_html_dir_html" \
-        render_maxpreviews_html="$render_maxpreviews_html" \
-        render_next_html="$render_next_html" \
-        render_original_basepath_is_set="$render_original_basepath_is_set" \
-        render_original_basepath_html="$render_original_basepath_html" \
-        render_page_num_html="$render_page_num_html" \
-        render_photo_html="$render_photo_html" \
-        render_photos_dir_html="$render_photos_dir_html" \
-        render_prev_html="$render_prev_html" \
-        render_preview_num_html="$render_preview_num_html" \
-        render_redirect_page_html="$render_redirect_page_html" \
-        render_show_header_bar="$render_show_header_bar" \
-        render_tarball_include="$render_tarball_include" \
-        render_tarball_name_html="$render_tarball_name_html" \
-        render_thumbheight_html="$render_thumbheight_html" \
-        render_thumbs_dir_html="$render_thumbs_dir_html" \
-        render_title_html="$render_title_html" \
-        render_view_next_html="$render_view_next_html" \
-        render_view_prev_html="$render_view_prev_html" \
-        bash -euo pipefail -- "$template_path" >> "$output_path"
+    if env -i PATH="$PATH" BASH_ENV="$context_file" \
+        bash -euo pipefail -- "$template_path" >> "$output_path"; then
+        rm -f "$context_file"
+    else
+        status=$?
+        rm -f "$context_file"
+        return "$status"
+    fi
 }
 
 parse_template_context() {
@@ -637,6 +622,54 @@ parse_template_context() {
     done
 }
 
+serialize_template_render_var() {
+    local -r name="$1"; shift
+    local -r value="$1"; shift
+
+    printf '%s=%q\n' "$name" "$value"
+}
+
+serialize_template_render_context() {
+    serialize_template_render_var \
+        render_animation_class_html "$render_animation_class_html"
+    serialize_template_render_var render_backhref_css "$render_backhref_css"
+    serialize_template_render_var render_backhref_html "$render_backhref_html"
+    serialize_template_render_var \
+        render_background_image_css "$render_background_image_css"
+    serialize_template_render_var render_blurs_dir_css "$render_blurs_dir_css"
+    serialize_template_render_var \
+        render_current_date_text "$render_current_date_text"
+    serialize_template_render_var render_enter_page_html "$render_enter_page_html"
+    serialize_template_render_var \
+        render_exif_details_html "$render_exif_details_html"
+    serialize_template_render_var render_height_html "$render_height_html"
+    serialize_template_render_var render_html_dir_html "$render_html_dir_html"
+    serialize_template_render_var \
+        render_maxpreviews_html "$render_maxpreviews_html"
+    serialize_template_render_var render_next_html "$render_next_html"
+    serialize_template_render_var \
+        render_original_basepath_is_set "$render_original_basepath_is_set"
+    serialize_template_render_var \
+        render_original_basepath_html "$render_original_basepath_html"
+    serialize_template_render_var render_page_num_html "$render_page_num_html"
+    serialize_template_render_var render_photo_html "$render_photo_html"
+    serialize_template_render_var render_photos_dir_html "$render_photos_dir_html"
+    serialize_template_render_var render_prev_html "$render_prev_html"
+    serialize_template_render_var \
+        render_preview_num_html "$render_preview_num_html"
+    serialize_template_render_var \
+        render_redirect_page_html "$render_redirect_page_html"
+    serialize_template_render_var render_show_header_bar "$render_show_header_bar"
+    serialize_template_render_var render_tarball_include "$render_tarball_include"
+    serialize_template_render_var \
+        render_tarball_name_html "$render_tarball_name_html"
+    serialize_template_render_var render_thumbheight_html "$render_thumbheight_html"
+    serialize_template_render_var render_thumbs_dir_html "$render_thumbs_dir_html"
+    serialize_template_render_var render_title_html "$render_title_html"
+    serialize_template_render_var render_view_next_html "$render_view_next_html"
+    serialize_template_render_var render_view_prev_html "$render_view_prev_html"
+}
+
 prepare_template_render_vars() {
     local -r context_name="$1"; shift
 
diff --git a/src/photoalbum.sh b/src/photoalbum.sh
index 9f9cc7d..32a38ee 100755
--- a/src/photoalbum.sh
+++ b/src/photoalbum.sh
@@ -576,38 +576,23 @@ validate_template_context() {
 source_template_file() {
     local -r template_path="$1"; shift
     local -r output_path="$1"; shift
+    local context_file
+    local -i status=0
+
+    context_file=$(mktemp)
+    {
+        serialize_template_render_context
+        printf 'unset BASH_ENV\n'
+    } > "$context_file"
 
-    env -i \
-        PATH="$PATH" \
-        render_animation_class_html="$render_animation_class_html" \
-        render_backhref_css="$render_backhref_css" \
-        render_backhref_html="$render_backhref_html" \
-        render_background_image_css="$render_background_image_css" \
-        render_blurs_dir_css="$render_blurs_dir_css" \
-        render_current_date_text="$render_current_date_text" \
-        render_enter_page_html="$render_enter_page_html" \
-        render_exif_details_html="$render_exif_details_html" \
-        render_height_html="$render_height_html" \
-        render_html_dir_html="$render_html_dir_html" \
-        render_maxpreviews_html="$render_maxpreviews_html" \
-        render_next_html="$render_next_html" \
-        render_original_basepath_is_set="$render_original_basepath_is_set" \
-        render_original_basepath_html="$render_original_basepath_html" \
-        render_page_num_html="$render_page_num_html" \
-        render_photo_html="$render_photo_html" \
-        render_photos_dir_html="$render_photos_dir_html" \
-        render_prev_html="$render_prev_html" \
-        render_preview_num_html="$render_preview_num_html" \
-        render_redirect_page_html="$render_redirect_page_html" \
-        render_show_header_bar="$render_show_header_bar" \
-        render_tarball_include="$render_tarball_include" \
-        render_tarball_name_html="$render_tarball_name_html" \
-        render_thumbheight_html="$render_thumbheight_html" \
-        render_thumbs_dir_html="$render_thumbs_dir_html" \
-        render_title_html="$render_title_html" \
-        render_view_next_html="$render_view_next_html" \
-        render_view_prev_html="$render_view_prev_html" \
-        bash -euo pipefail -- "$template_path" >> "$output_path"
+    if env -i PATH="$PATH" BASH_ENV="$context_file" \
+        bash -euo pipefail -- "$template_path" >> "$output_path"; then
+        rm -f "$context_file"
+    else
+        status=$?
+        rm -f "$context_file"
+        return "$status"
+    fi
 }
 
 parse_template_context() {
@@ -637,6 +622,54 @@ parse_template_context() {
     done
 }
 
+serialize_template_render_var() {
+    local -r name="$1"; shift
+    local -r value="$1"; shift
+
+    printf '%s=%q\n' "$name" "$value"
+}
+
+serialize_template_render_context() {
+    serialize_template_render_var \
+        render_animation_class_html "$render_animation_class_html"
+    serialize_template_render_var render_backhref_css "$render_backhref_css"
+    serialize_template_render_var render_backhref_html "$render_backhref_html"
+    serialize_template_render_var \
+        render_background_image_css "$render_background_image_css"
+    serialize_template_render_var render_blurs_dir_css "$render_blurs_dir_css"
+    serialize_template_render_var \
+        render_current_date_text "$render_current_date_text"
+    serialize_template_render_var render_enter_page_html "$render_enter_page_html"
+    serialize_template_render_var \
+        render_exif_details_html "$render_exif_details_html"
+    serialize_template_render_var render_height_html "$render_height_html"
+    serialize_template_render_var render_html_dir_html "$render_html_dir_html"
+    serialize_template_render_var \
+        render_maxpreviews_html "$render_maxpreviews_html"
+    serialize_template_render_var render_next_html "$render_next_html"
+    serialize_template_render_var \
+        render_original_basepath_is_set "$render_original_basepath_is_set"
+    serialize_template_render_var \
+        render_original_basepath_html "$render_original_basepath_html"
+    serialize_template_render_var render_page_num_html "$render_page_num_html"
+    serialize_template_render_var render_photo_html "$render_photo_html"
+    serialize_template_render_var render_photos_dir_html "$render_photos_dir_html"
+    serialize_template_render_var render_prev_html "$render_prev_html"
+    serialize_template_render_var \
+        render_preview_num_html "$render_preview_num_html"
+    serialize_template_render_var \
+        render_redirect_page_html "$render_redirect_page_html"
+    serialize_template_render_var render_show_header_bar "$render_show_header_bar"
+    serialize_template_render_var render_tarball_include "$render_tarball_include"
+    serialize_template_render_var \
+        render_tarball_name_html "$render_tarball_name_html"
+    serialize_template_render_var render_thumbheight_html "$render_thumbheight_html"
+    serialize_template_render_var render_thumbs_dir_html "$render_thumbs_dir_html"
+    serialize_template_render_var render_title_html "$render_title_html"
+    serialize_template_render_var render_view_next_html "$render_view_next_html"
+    serialize_template_render_var render_view_prev_html "$render_view_prev_html"
+}
+
 prepare_template_render_vars() {
     local -r context_name="$1"; shift
 
diff --git a/tests/cli.sh b/tests/cli.sh
index 8056da5..975b724 100755
--- a/tests/cli.sh
+++ b/tests/cli.sh
@@ -2483,6 +2483,45 @@ test_generate_templates_cannot_read_renderer_internals() {
     test::teardown
 }
 
+test_generate_templates_cannot_read_serialized_context_hook() {
+    local config_file
+    local fake_bin
+    local output
+    local template_dir
+
+    test::setup
+    fake_bin="$TEST_TMPDIR/bin"
+    config_file="$TEST_TMPDIR/photoalbum.conf"
+    template_dir="$TEST_TMPDIR/templates"
+
+    test::install_fake_imagemagick "$fake_bin"
+    PATH="$fake_bin:$PATH" \
+        test::generate_fixture_images "$TEST_TMPDIR/incoming"
+    cp -R "$TEST_REPO_ROOT/share/templates/default" "$template_dir"
+    # shellcheck disable=SC2016
+    printf 'printf "bash env: %%s\\n" "${BASH_ENV}"\n' \
+        > "$template_dir/preview.tmpl"
+    mkdir -p "$TEST_TMPDIR/dist"
+    printf 'old index\n' > "$TEST_TMPDIR/dist/index.html"
+    test::write_album_config \
+        "$config_file" "$TEST_TMPDIR/incoming" "$TEST_TMPDIR/dist" \
+        'Renderer context album' 40
+    printf 'TEMPLATE_DIR=%q\n' "$template_dir" >> "$config_file"
+
+    output=$(
+        cd "$TEST_TMPDIR"
+        PATH="$fake_bin:$PATH" BASH_ENV=ambient \
+            test::capture_failure_output "$TEST_PHOTOALBUM" --generate
+    )
+
+    test::assert_contains 'BASH_ENV: unbound variable' "$output"
+    test "$(<"$TEST_TMPDIR/dist/index.html")" = 'old index'
+    test::assert_path_absent "$TEST_TMPDIR/dist/photos/01-landscape.jpg"
+    test::assert_path_absent "$TEST_TMPDIR/dist/photoalbum.json"
+    test::assert_no_staging_dirs "$TEST_TMPDIR"
+    test::teardown
+}
+
 test_generate_swap_failure_restores_dist() {
     local config_file
     local fake_bin
@@ -3048,6 +3087,9 @@ main() {
         '--generate templates cannot read renderer internals' \
         test_generate_templates_cannot_read_renderer_internals
     test::run_case \
+        '--generate templates cannot read serialized context hook' \
+        test_generate_templates_cannot_read_serialized_context_hook
+    test::run_case \
         '--generate swap failure restores final dist' \
         test_generate_swap_failure_restores_dist
     test::run_case \