Files
RuDS/crates/bds-core/src/engine/template.rs

831 lines
26 KiB
Rust

use std::fs;
use std::path::Path;
use crate::db::DbConnection as Connection;
use crate::db::schema::{posts, tags};
use diesel::prelude::*;
use uuid::Uuid;
use crate::db::queries::template as qt;
use crate::engine::{EngineError, EngineResult, domain_events};
use crate::model::{DomainEntity, NotificationAction, Template, TemplateKind, TemplateStatus};
use crate::util::frontmatter::{TemplateFrontmatter, write_template_file};
use crate::util::{atomic_write_str, ensure_unique, now_unix_ms, slugify};
const ALLOWED_LIQUID_TAGS: &[&str] = &[
"if", "elsif", "else", "endif", "for", "endfor", "assign", "render",
];
const ALLOWED_LIQUID_FILTERS: &[&str] = &[
"escape",
"url_encode",
"default",
"append",
"i18n",
"markdown",
"slugify",
];
/// Create a new draft template. Content stored in DB, no file written.
pub fn create_template(
conn: &Connection,
project_id: &str,
title: &str,
kind: TemplateKind,
content: &str,
) -> EngineResult<Template> {
let slug_source = if title.is_empty() { "untitled" } else { title };
let base_slug = slugify(slug_source);
let base_slug = if base_slug.is_empty() {
"untitled".to_string()
} else {
base_slug
};
let slug = ensure_unique(&base_slug, |candidate| {
qt::get_template_by_slug(conn, project_id, candidate).is_ok()
});
let now = now_unix_ms();
let id = Uuid::new_v4().to_string();
let tpl = Template {
id,
project_id: project_id.to_string(),
slug,
title: title.to_string(),
kind,
enabled: true,
version: 1,
file_path: String::new(),
status: TemplateStatus::Draft,
content: Some(content.to_string()),
created_at: now,
updated_at: now,
};
qt::insert_template(conn, &tpl)?;
emit_template(&tpl, NotificationAction::Created);
Ok(tpl)
}
/// Update a template's metadata and/or content. Bumps version.
#[expect(
clippy::too_many_arguments,
reason = "optional arguments represent independent template field changes"
)]
pub fn update_template(
conn: &Connection,
template_id: &str,
project_id: &str,
title: Option<&str>,
slug: Option<&str>,
kind: Option<TemplateKind>,
enabled: Option<bool>,
content: Option<&str>,
) -> EngineResult<Template> {
let mut tpl = qt::get_template_by_id(conn, template_id)?;
// Slug uniqueness check
if let Some(new_slug) = slug
&& new_slug != tpl.slug
&& qt::get_template_by_slug(conn, project_id, new_slug).is_ok()
{
return Err(EngineError::Conflict(format!(
"template slug '{new_slug}' already exists"
)));
}
if let Some(t) = title {
tpl.title = t.to_string();
}
if let Some(s) = slug {
tpl.slug = s.to_string();
}
if let Some(k) = kind {
tpl.kind = k;
}
if let Some(e) = enabled {
tpl.enabled = e;
}
if let Some(c) = content {
tpl.content = Some(c.to_string());
}
// If published, transition back to draft on edit
if tpl.status == TemplateStatus::Published {
// Reload content from file if needed
if tpl.content.is_none() && !tpl.file_path.is_empty() {
// Content will come from the file when we read for publish
// For update we need the new content from the caller
}
tpl.status = TemplateStatus::Draft;
}
tpl.version += 1;
tpl.updated_at = now_unix_ms();
qt::update_template(conn, &tpl)?;
emit_template(&tpl, NotificationAction::Updated);
Ok(tpl)
}
/// Save template content (editor save). Updates DB, bumps version.
pub fn save_template(
conn: &Connection,
template_id: &str,
content: &str,
) -> EngineResult<Template> {
let mut tpl = qt::get_template_by_id(conn, template_id)?;
tpl.content = Some(content.to_string());
tpl.version += 1;
tpl.updated_at = now_unix_ms();
// If published, transition back to draft
if tpl.status == TemplateStatus::Published {
tpl.status = TemplateStatus::Draft;
}
qt::update_template(conn, &tpl)?;
emit_template(&tpl, NotificationAction::Updated);
Ok(tpl)
}
/// Validate Liquid template syntax. Returns Ok(()) or a parse error message.
pub fn validate_template(content: &str) -> Result<(), String> {
validate_liquid_subset(content)?;
crate::render::validate_liquid_template_syntax(content)
}
/// Publish a template: write frontmatter+body to file, clear content in DB.
pub fn publish_template(
conn: &Connection,
data_dir: &Path,
template_id: &str,
) -> EngineResult<Template> {
let mut tpl = qt::get_template_by_id(conn, template_id)?;
if tpl.status == TemplateStatus::Published {
return Err(EngineError::Conflict(
"template is already published".to_string(),
));
}
let body = tpl.content.clone().unwrap_or_default();
// Validate before publishing
validate_template(&body).map_err(EngineError::Validation)?;
let now = now_unix_ms();
let rel_path = format!("templates/{}.liquid", tpl.slug);
let abs_path = data_dir.join(&rel_path);
// Ensure templates/ directory exists
if let Some(parent) = abs_path.parent() {
fs::create_dir_all(parent)?;
}
// Build frontmatter
let fm = TemplateFrontmatter {
id: tpl.id.clone(),
project_id: Some(tpl.project_id.clone()),
slug: tpl.slug.clone(),
title: tpl.title.clone(),
kind: template_kind_to_frontmatter(&tpl.kind),
enabled: tpl.enabled,
version: tpl.version,
created_at: tpl.created_at,
updated_at: now,
};
let file_content = write_template_file(&fm, &body);
atomic_write_str(&abs_path, &file_content)?;
// Update DB
tpl.status = TemplateStatus::Published;
tpl.file_path = rel_path;
tpl.content = None;
tpl.updated_at = now;
qt::update_template(conn, &tpl)?;
emit_template(&tpl, NotificationAction::Updated);
Ok(tpl)
}
/// Unpublish a template: read content from file back into DB, set status to draft.
pub fn unpublish_template(
conn: &Connection,
data_dir: &Path,
template_id: &str,
) -> EngineResult<Template> {
let mut tpl = qt::get_template_by_id(conn, template_id)?;
if tpl.status != TemplateStatus::Published {
return Err(EngineError::Conflict(
"template is not published".to_string(),
));
}
// Read body from file
if !tpl.file_path.is_empty() {
let abs_path = data_dir.join(&tpl.file_path);
if abs_path.exists() {
let file_content = fs::read_to_string(&abs_path)?;
let (_fm, body) = crate::util::frontmatter::read_template_file(&file_content)
.map_err(EngineError::Parse)?;
tpl.content = Some(body);
}
}
tpl.status = TemplateStatus::Draft;
tpl.updated_at = now_unix_ms();
qt::update_template(conn, &tpl)?;
emit_template(&tpl, NotificationAction::Updated);
Ok(tpl)
}
/// Delete a template. Checks for references from posts and tags.
pub fn delete_template(
conn: &Connection,
data_dir: &Path,
template_id: &str,
force: bool,
) -> EngineResult<()> {
let tpl = qt::get_template_by_id(conn, template_id)?;
// Check references
let referencing_posts = count_posts_using_template(conn, &tpl.slug)?;
let referencing_tags = count_tags_using_template(conn, &tpl.slug)?;
if (referencing_posts > 0 || referencing_tags > 0) && !force {
return Err(EngineError::Conflict(format!(
"template is referenced by {} posts and {} tags",
referencing_posts, referencing_tags
)));
}
// Force: null out references
if force {
if referencing_posts > 0 {
null_template_slug_on_posts(conn, &tpl.slug)?;
}
if referencing_tags > 0 {
null_template_slug_on_tags(conn, &tpl.slug)?;
}
}
// Delete file if exists
if !tpl.file_path.is_empty() {
let abs_path = data_dir.join(&tpl.file_path);
if abs_path.exists() {
fs::remove_file(&abs_path)?;
}
}
qt::delete_template(conn, template_id)?;
emit_template(&tpl, NotificationAction::Deleted);
Ok(())
}
fn emit_template(template: &Template, action: NotificationAction) {
domain_events::entity_changed(
&template.project_id,
DomainEntity::Template,
&template.id,
action,
);
}
// --- Helper functions ---
fn template_kind_to_frontmatter(kind: &TemplateKind) -> String {
match kind {
TemplateKind::Post => "post".to_string(),
TemplateKind::List => "list".to_string(),
TemplateKind::NotFound => "not_found".to_string(),
TemplateKind::Partial => "partial".to_string(),
}
}
fn validate_liquid_subset(content: &str) -> Result<(), String> {
let mut cursor = 0;
while let Some((offset, is_tag)) = next_liquid_markup(&content[cursor..]) {
let markup_start = cursor + offset + 2;
let close = if is_tag { "%}" } else { "}}" };
let Some(close_offset) = find_unquoted(&content[markup_start..], close) else {
break;
};
let markup_end = markup_start + close_offset;
let markup = content[markup_start..markup_end]
.trim()
.trim_start_matches('-')
.trim_end_matches('-')
.trim();
let tag = is_tag.then(|| identifier_at_start(markup)).flatten();
if let Some(tag) = tag
&& !ALLOWED_LIQUID_TAGS.contains(&tag)
{
return Err(format!("unsupported tag: {tag}"));
}
validate_liquid_filters(markup)?;
if let Some(tag @ ("if" | "elsif")) = tag {
validate_liquid_operators(markup[tag.len()..].trim_start())?;
}
cursor = markup_end + close.len();
}
Ok(())
}
fn next_liquid_markup(content: &str) -> Option<(usize, bool)> {
match (content.find("{%"), content.find("{{")) {
(Some(tag), Some(output)) if tag <= output => Some((tag, true)),
(Some(_), Some(output)) => Some((output, false)),
(Some(tag), None) => Some((tag, true)),
(None, Some(output)) => Some((output, false)),
(None, None) => None,
}
}
fn find_unquoted(content: &str, needle: &str) -> Option<usize> {
let bytes = content.as_bytes();
let needle = needle.as_bytes();
let mut quote = None;
let mut escaped = false;
let mut index = 0;
while index + needle.len() <= bytes.len() {
let byte = bytes[index];
if let Some(active_quote) = quote {
if escaped {
escaped = false;
} else if byte == b'\\' {
escaped = true;
} else if byte == active_quote {
quote = None;
}
} else if matches!(byte, b'\'' | b'"') {
quote = Some(byte);
} else if &bytes[index..index + needle.len()] == needle {
return Some(index);
}
index += 1;
}
None
}
fn identifier_at_start(content: &str) -> Option<&str> {
let end = content
.find(|character: char| !is_liquid_identifier(character))
.unwrap_or(content.len());
(end > 0).then(|| &content[..end])
}
fn is_liquid_identifier(character: char) -> bool {
character.is_ascii_alphanumeric() || matches!(character, '_' | '-')
}
fn validate_liquid_filters(markup: &str) -> Result<(), String> {
for pipe in unquoted_byte_positions(markup, b'|') {
let after_pipe = markup[pipe + 1..].trim_start();
if let Some(filter) = identifier_at_start(after_pipe)
&& !ALLOWED_LIQUID_FILTERS.contains(&filter)
{
return Err(format!("unsupported filter: {filter}"));
}
}
Ok(())
}
fn validate_liquid_operators(markup: &str) -> Result<(), String> {
let bytes = markup.as_bytes();
let mut quote = None;
let mut escaped = false;
let mut index = 0;
while index < bytes.len() {
let byte = bytes[index];
if let Some(active_quote) = quote {
if escaped {
escaped = false;
} else if byte == b'\\' {
escaped = true;
} else if byte == active_quote {
quote = None;
}
index += 1;
continue;
}
if matches!(byte, b'\'' | b'"') {
quote = Some(byte);
index += 1;
continue;
}
let operator = match (byte, bytes.get(index + 1).copied()) {
(b'!', Some(b'=')) => Some("!="),
(b'>', Some(b'=')) => Some(">="),
(b'<', Some(b'=')) => Some("<="),
(b'<', _) => Some("<"),
_ => None,
};
if let Some(operator) = operator {
return Err(format!("unsupported operator: {operator}"));
}
if bytes[index..].starts_with(b"contains")
&& is_word_boundary(bytes.get(index.wrapping_sub(1)).copied())
&& is_word_boundary(bytes.get(index + "contains".len()).copied())
&& !markup[..index].trim_end().is_empty()
&& !markup[index + "contains".len()..].trim_start().is_empty()
&& !markup[..index].trim_end().ends_with('.')
{
return Err("unsupported operator: contains".to_string());
}
index += 1;
}
Ok(())
}
fn is_word_boundary(byte: Option<u8>) -> bool {
byte.is_none_or(|byte| !byte.is_ascii_alphanumeric() && !matches!(byte, b'_' | b'-'))
}
fn unquoted_byte_positions(content: &str, target: u8) -> Vec<usize> {
let mut positions = Vec::new();
let mut quote = None;
let mut escaped = false;
for (index, byte) in content.bytes().enumerate() {
if let Some(active_quote) = quote {
if escaped {
escaped = false;
} else if byte == b'\\' {
escaped = true;
} else if byte == active_quote {
quote = None;
}
} else if matches!(byte, b'\'' | b'"') {
quote = Some(byte);
} else if byte == target {
positions.push(index);
}
}
positions
}
fn count_posts_using_template(conn: &Connection, slug: &str) -> EngineResult<usize> {
let count: i64 = conn.with(|c| {
posts::table
.filter(posts::template_slug.eq(slug))
.count()
.get_result(c)
})?;
Ok(count as usize)
}
fn count_tags_using_template(conn: &Connection, slug: &str) -> EngineResult<usize> {
let count: i64 = conn.with(|c| {
tags::table
.filter(tags::post_template_slug.eq(slug))
.count()
.get_result(c)
})?;
Ok(count as usize)
}
fn null_template_slug_on_posts(conn: &Connection, slug: &str) -> EngineResult<()> {
conn.with(|c| {
diesel::update(posts::table.filter(posts::template_slug.eq(slug)))
.set(posts::template_slug.eq(None::<String>))
.execute(c)
})?;
Ok(())
}
fn null_template_slug_on_tags(conn: &Connection, slug: &str) -> EngineResult<()> {
conn.with(|c| {
diesel::update(tags::table.filter(tags::post_template_slug.eq(slug)))
.set(tags::post_template_slug.eq(None::<String>))
.execute(c)
})?;
Ok(())
}
#[cfg(test)]
mod tests {
use super::*;
use crate::db::Database;
use crate::db::queries::project::{insert_project, make_test_project};
use tempfile::TempDir;
fn setup() -> (Database, TempDir) {
let db = Database::open_in_memory().unwrap();
db.migrate().unwrap();
insert_project(db.conn(), &make_test_project("p1", "blog")).unwrap();
let dir = TempDir::new().unwrap();
(db, dir)
}
#[test]
fn create_draft_template() {
let (db, _dir) = setup();
let tpl = create_template(
db.conn(),
"p1",
"My Template",
TemplateKind::Post,
"<p>hello</p>",
)
.unwrap();
assert_eq!(tpl.title, "My Template");
assert_eq!(tpl.slug, "my-template");
assert_eq!(tpl.kind, TemplateKind::Post);
assert_eq!(tpl.status, TemplateStatus::Draft);
assert_eq!(tpl.content, Some("<p>hello</p>".to_string()));
assert!(tpl.file_path.is_empty());
assert!(tpl.enabled);
assert_eq!(tpl.version, 1);
}
#[test]
fn create_template_deduplicates_slug() {
let (db, _dir) = setup();
let t1 = create_template(db.conn(), "p1", "Test", TemplateKind::Post, "").unwrap();
let t2 = create_template(db.conn(), "p1", "Test", TemplateKind::Post, "").unwrap();
assert_eq!(t1.slug, "test");
assert_eq!(t2.slug, "test-2");
}
#[test]
fn update_template_bumps_version() {
let (db, _dir) = setup();
let tpl = create_template(db.conn(), "p1", "Tpl", TemplateKind::Post, "old").unwrap();
let updated = update_template(
db.conn(),
&tpl.id,
"p1",
Some("New Title"),
None,
None,
None,
Some("new content"),
)
.unwrap();
assert_eq!(updated.title, "New Title");
assert_eq!(updated.content, Some("new content".to_string()));
assert_eq!(updated.version, 2);
}
#[test]
fn update_template_slug_conflict() {
let (db, _dir) = setup();
create_template(db.conn(), "p1", "Alpha", TemplateKind::Post, "").unwrap();
let t2 = create_template(db.conn(), "p1", "Beta", TemplateKind::Post, "").unwrap();
let result = update_template(
db.conn(),
&t2.id,
"p1",
None,
Some("alpha"),
None,
None,
None,
);
assert!(result.is_err());
}
#[test]
fn save_template_updates_content() {
let (db, _dir) = setup();
let tpl = create_template(db.conn(), "p1", "Tpl", TemplateKind::Post, "old").unwrap();
let saved = save_template(db.conn(), &tpl.id, "new content").unwrap();
assert_eq!(saved.content, Some("new content".to_string()));
assert_eq!(saved.version, 2);
}
#[test]
fn publish_and_unpublish_template() {
let (db, dir) = setup();
let tpl = create_template(
db.conn(),
"p1",
"Pub",
TemplateKind::Post,
"<div>body</div>",
)
.unwrap();
// Publish
let published = publish_template(db.conn(), dir.path(), &tpl.id).unwrap();
assert_eq!(published.status, TemplateStatus::Published);
assert!(published.content.is_none());
assert_eq!(published.file_path, "templates/pub.liquid");
assert!(dir.path().join("templates/pub.liquid").exists());
// Unpublish
let unpublished = unpublish_template(db.conn(), dir.path(), &published.id).unwrap();
assert_eq!(unpublished.status, TemplateStatus::Draft);
assert_eq!(unpublished.content, Some("<div>body</div>".to_string()));
}
#[test]
fn publish_requires_draft() {
let (db, dir) = setup();
let tpl = create_template(db.conn(), "p1", "Tpl", TemplateKind::Post, "body").unwrap();
publish_template(db.conn(), dir.path(), &tpl.id).unwrap();
let result = publish_template(db.conn(), dir.path(), &tpl.id);
assert!(result.is_err());
}
#[test]
fn delete_template_removes_file() {
let (db, dir) = setup();
let tpl = create_template(db.conn(), "p1", "Del", TemplateKind::Post, "body").unwrap();
publish_template(db.conn(), dir.path(), &tpl.id).unwrap();
assert!(dir.path().join("templates/del.liquid").exists());
delete_template(db.conn(), dir.path(), &tpl.id, false).unwrap();
assert!(!dir.path().join("templates/del.liquid").exists());
assert!(qt::get_template_by_id(db.conn(), &tpl.id).is_err());
}
#[test]
fn validate_valid_liquid() {
assert!(validate_template("<div>{{ title }}</div>").is_ok());
assert!(validate_template("{% if x %}<p>y</p>{% endif %}").is_ok());
assert!(validate_template("{% for p in posts %}{{ p.title }}{% endfor %}").is_ok());
}
#[test]
fn validate_rejects_unsupported_liquid_tags() {
for tag in [
"unless",
"case",
"capture",
"tablerow",
"cycle",
"increment",
] {
let content = format!("{{% {tag} foo %}}bar{{% end{tag} %}}");
assert_eq!(
validate_template(&content),
Err(format!("unsupported tag: {tag}"))
);
}
}
#[test]
fn validate_rejects_unsupported_liquid_filters() {
for filter in ["upcase", "downcase", "date", "truncate", "split", "reverse"] {
let content = format!("{{{{ title | {filter} }}}}");
assert_eq!(
validate_template(&content),
Err(format!("unsupported filter: {filter}"))
);
}
}
#[test]
fn validate_rejects_unsupported_liquid_operators() {
for operator in ["!=", "<", ">=", "<=", "contains"] {
let content = format!("{{% if title {operator} other %}}yes{{% endif %}}");
assert_eq!(
validate_template(&content),
Err(format!("unsupported operator: {operator}"))
);
}
}
#[test]
fn validate_allows_the_complete_liquid_subset() {
for filter in [
"escape",
"url_encode",
"default: fallback",
"append: suffix",
"i18n: language",
"markdown: post.id, posts, post_paths, media_paths, language, prefix",
"slugify",
] {
let result = validate_template(&format!("{{{{ title | {filter} }}}}"));
assert!(
result.is_ok(),
"supported filter {filter} was rejected: {result:?}"
);
}
for content in [
"{% if title == other %}yes{% elsif total > 0 %}more{% else %}no{% endif %}",
"{% if published %}yes{% endif %}",
"{% if a == b and c > d %}yes{% endif %}",
"{% if a == b or c == blank %}yes{% endif %}",
"{% assign href = '/posts/' | append: post.slug %}",
"{% render 'partials/card', post: post %}",
"{%- for post in posts -%}{{- post.title | escape -}}{%- endfor -%}",
"{% if values.size > 0 and map[key] %}yes{% endif %}",
] {
let result = validate_template(content);
assert!(
result.is_ok(),
"supported syntax was rejected: {content}: {result:?}"
);
}
}
#[test]
fn bundled_starter_templates_conform_to_the_published_liquid_subset() {
for (name, content) in [
(
"single-post",
include_str!("../../../../assets/starter-templates/single-post.liquid"),
),
(
"post-list",
include_str!("../../../../assets/starter-templates/post-list.liquid"),
),
(
"not-found",
include_str!("../../../../assets/starter-templates/not-found.liquid"),
),
(
"head",
include_str!("../../../../assets/starter-templates/partials/head.liquid"),
),
(
"language-switcher",
include_str!(
"../../../../assets/starter-templates/partials/language-switcher.liquid"
),
),
(
"menu-items",
include_str!("../../../../assets/starter-templates/partials/menu-items.liquid"),
),
(
"menu",
include_str!("../../../../assets/starter-templates/partials/menu.liquid"),
),
(
"macro-gallery",
include_str!("../../../../assets/starter-templates/macros/gallery.liquid"),
),
(
"macro-youtube",
include_str!("../../../../assets/starter-templates/macros/youtube.liquid"),
),
(
"macro-vimeo",
include_str!("../../../../assets/starter-templates/macros/vimeo.liquid"),
),
(
"macro-photo-archive",
include_str!("../../../../assets/starter-templates/macros/photo-archive.liquid"),
),
(
"macro-tag-cloud",
include_str!("../../../../assets/starter-templates/macros/tag-cloud.liquid"),
),
] {
let result = validate_template(content);
assert!(result.is_ok(), "starter template {name}: {result:?}");
}
}
#[test]
fn publish_rejects_unsupported_filter_and_leaves_template_draft() {
let (db, dir) = setup();
let template = create_template(
db.conn(),
"p1",
"Strict",
TemplateKind::Post,
"{{ title | upcase }}",
)
.unwrap();
let error = publish_template(db.conn(), dir.path(), &template.id).unwrap_err();
assert!(error.to_string().contains("unsupported filter: upcase"));
let reloaded = qt::get_template_by_id(db.conn(), &template.id).unwrap();
assert_eq!(reloaded.status, TemplateStatus::Draft);
assert_eq!(reloaded.content.as_deref(), Some("{{ title | upcase }}"));
assert!(!dir.path().join("templates/strict.liquid").exists());
}
#[test]
fn validate_unclosed_output() {
assert!(validate_template("<div>{{ title </div>").is_err());
}
#[test]
fn validate_unclosed_if() {
assert!(validate_template("{% if x %}<p>y</p>").is_err());
}
#[test]
fn validate_unmatched_endif() {
assert!(validate_template("<p>y</p>{% endif %}").is_err());
}
#[test]
fn validate_unclosed_for() {
assert!(validate_template("{% for p in posts %}{{ p.title }}").is_err());
}
}