v/vlib/x/templating/dtm/tmpl.v

356 lines
11 KiB
V

// Copyright (c) 2019-2024 Alexander Medvednikov. All rights reserved.
// Use of this source code is governed by an MIT license
// that can be found in the LICENSE file.
/*
This source code originates from the internal V compiler 'vlib/v/parser/tmpl.v' and
has been heavily modified for the needs of the Dynamic Template Manager. Thanks to its original author, Alexander Medvednikov.
*/
module dtm
import os
import strings
enum State {
simple // default - no special interpretation of tags, *at all*!
// That is suitable for the general case of text template interpolation,
// for example for interpolating arbitrary source code (even V source) templates.
//
html // default, only when the template extension is .html
css // <style>
js // <script>
// span // span.{
}
fn (mut state State) update(line string) {
trimmed_line := line.trim_space()
if is_html_open_tag('style', line) {
state = .css
} else if trimmed_line == '</style>' {
state = .html
} else if is_html_open_tag('script', line) {
state = .js
} else if trimmed_line == '</script>' {
state = .html
}
}
const tmpl_str_end = "')\n"
// check HTML open tag `<name attr="x" >`
fn is_html_open_tag(name string, s string) bool {
trimmed_line := s.trim_space()
mut len := trimmed_line.len
if len < name.len {
return false
}
mut sub := trimmed_line[0..1]
if sub != '<' { // not start with '<'
return false
}
sub = trimmed_line[len - 1..len]
if sub != '>' { // not end with '<'
return false
}
sub = trimmed_line[len - 2..len - 1]
if sub == '/' { // self-closing
return false
}
sub = trimmed_line[1..len - 1]
if sub.contains_any('<>') { // `<name <bad> >`
return false
}
if sub == name { // `<name>`
return true
} else {
len = name.len
if sub.len <= len { // `<nam>` or `<meme>`
return false
}
if sub[..len + 1] != '${name} ' { // not `<name ...>`
return false
}
return true
}
}
fn replace_placeholders_with_data(line string, data &map[string]DtmMultiTypeMap, state State) string {
mut rline := line
mut need_include_html := false
for key, value in data {
mut placeholder := '$${key}'
if placeholder.ends_with(include_html_key_tag) {
placeholder = placeholder.all_before_last(include_html_key_tag)
need_include_html = true
}
if !rline.contains(placeholder) {
need_include_html = false
continue
}
mut val_str := ''
match value {
i8, i16, int, i64, u8, u16, u32, u64, f32, f64 {
// Converts value to string
temp_val := value.str()
// Filters the string value for safe insertion
val_str = filter(temp_val)
}
string {
// Checks if the placeholder allows HTML inclusion
if need_include_html {
if state == State.html {
// Iterates over allowed HTML tags for inclusion
for tag in allowed_tags {
// Escapes the HTML tag
escaped_tag := filter(tag)
// Replaces the escaped tags with actual HTML tags in the value
val_str = value.replace(escaped_tag, tag)
}
} else {
val_str = filter(value)
}
need_include_html = false
} else {
// Filters the string value for safe insertion
val_str = filter(value)
}
}
}
rline = rline.replace(placeholder, val_str)
}
// If no output is found for the placeholder being processed, then the placeholder is escaped
if rline.contains('$') {
rline = filter(rline)
}
return rline
}
fn insert_template_code(fn_name string, tmpl_str_start string, line string, data &map[string]DtmMultiTypeMap,
state State) string {
// HTML, may include `@var`
// escaped by cgen, unless it's a `vweb.RawHtml` string
trailing_bs := dtm.tmpl_str_end + 'sb_${fn_name}.write_u8(92)\n' + tmpl_str_start
round1 := ['\\', '\\\\', r"'", "\\'", r'@', r'$']
round2 := [r'$$', r'\@', r'.$', r'.@']
mut rline := line.replace_each(round1).replace_each(round2)
comptime_call_str := rline.find_between('\${', '}')
if comptime_call_str.contains("\\'") {
rline = rline.replace(comptime_call_str, comptime_call_str.replace("\\'", r"'"))
}
if rline.ends_with('\\') {
rline = rline[0..rline.len - 2] + trailing_bs
}
if rline.contains('$') {
rline = replace_placeholders_with_data(rline, data, state)
}
return rline
}
// compile_file compiles the content of a file by the given path as a template
fn compile_template_file(template_file string, fn_name string, data &map[string]DtmMultiTypeMap) string {
mut lines := os.read_lines(template_file) or {
eprintln('${message_signature_error} Template generator can not reading from ${template_file} file')
return internat_server_error
}
basepath := os.dir(template_file)
tmpl_str_start := "\tsb_${fn_name}.write_string('"
mut source := strings.new_builder(1000)
mut state := State.simple
template_ext := os.file_ext(template_file)
if template_ext.to_lower() == '.html' {
state = .html
}
mut in_span := false
mut end_of_line_pos := 0
mut start_of_line_pos := 0
mut tline_number := -1 // keep the original line numbers, even after insert/delete ops on lines; `i` changes
for i := 0; i < lines.len; i++ {
line := lines[i]
tline_number++
start_of_line_pos = end_of_line_pos
end_of_line_pos += line.len + 1
if state != .simple {
state.update(line)
}
$if trace_tmpl ? {
eprintln('>>> tfile: ${template_file}, spos: ${start_of_line_pos:6}, epos:${end_of_line_pos:6}, fi: ${tline_number:5}, i: ${i:5}, state: ${state:10}, line: ${line}')
}
if line.contains('@header') {
position := line.index('@header') or { 0 }
eprintln("${message_signature_warn} Please use @include 'header' instead of @header (deprecated), position : ${position}")
continue
}
if line.contains('@footer') {
position := line.index('@footer') or { 0 }
eprintln("${message_signature_warn} Please use @include 'footer' instead of @footer (deprecated), position : ${position}")
continue
}
if line.contains('@include ') {
lines.delete(i)
// Allow single or double quoted paths.
mut file_name := if line.contains('"') {
line.split('"')[1]
} else if line.contains("'") {
line.split("'")[1]
} else {
s := '@include '
position := line.index(s) or { 0 }
eprintln("${message_signature_error} path for @include must be quoted with ' or \" without line breaks or extraneous characters between @include and the quotes, position : ${position}")
return internat_server_error
}
mut file_ext := os.file_ext(file_name)
if file_ext == '' {
file_ext = '.html'
}
file_name = file_name.replace(file_ext, '')
// relative path, starting with the current folder
mut templates_folder := os.real_path(basepath)
if file_name.contains('/') && file_name.starts_with('/') {
// an absolute path
templates_folder = ''
}
file_path := os.real_path(os.join_path_single(templates_folder, '${file_name}${file_ext}'))
$if trace_tmpl ? {
eprintln('>>> basepath: "${basepath}" , template_file: "${template_file}" , fn_name: "${fn_name}" , @include line: "${line}" , file_name: "${file_name}" , file_ext: "${file_ext}" , templates_folder: "${templates_folder}" , file_path: "${file_path}"')
}
file_content := os.read_file(file_path) or {
position := line.index('@include ') or { 0 } + '@include '.len
eprintln('${message_signature_error} Reading @include file "${file_name}" from path: ${file_path} failed, position : ${position}')
return internat_server_error
}
file_splitted := file_content.split_into_lines().reverse()
for f in file_splitted {
tline_number--
lines.insert(i, f)
}
i--
continue
}
if line.contains('@if ') {
/* source.writeln(dtm.tmpl_str_end)
pos := line.index('@if') or { continue }
source.writeln('if ' + line[pos + 4..] + '{')
source.writeln(tmpl_str_start) */
continue
}
if line.contains('@end') {
/* // Remove new line byte
source.go_back(1)
source.writeln(dtm.tmpl_str_end)
source.writeln('}')
source.writeln(tmpl_str_start) */
continue
}
if line.contains('@else') {
// Remove new line byte
source.go_back(1)
/* source.writeln(dtm.tmpl_str_end)
source.writeln(' } else { ')
source.writeln(tmpl_str_start) */
continue
}
if line.contains('@for') {
/* source.writeln(dtm.tmpl_str_end)
pos := line.index('@for') or { continue }
source.writeln('for ' + line[pos + 4..] + '{')
source.writeln(tmpl_str_start) */
continue
}
if state == .simple {
// by default, just copy 1:1
source.writeln(insert_template_code(fn_name, tmpl_str_start, line, data, state))
continue
}
// The .simple mode ends here. The rest handles .html/.css/.js state transitions.
if state != .simple {
if line.contains('@js ') {
pos := line.index('@js') or { continue }
source.write_string('<script src="')
source.write_string(line[pos + 5..line.len - 1])
source.writeln('"></script>')
continue
}
if line.contains('@css ') {
pos := line.index('@css') or { continue }
source.write_string('<link href="')
source.write_string(line[pos + 6..line.len - 1])
source.writeln('" rel="stylesheet" type="text/css">')
continue
}
}
match state {
.html {
line_t := line.trim_space()
if line_t.starts_with('span.') && line.ends_with('{') {
//`span.header {` => `<span class='header'>`
class := line.find_between('span.', '{').trim_space()
source.writeln('<span class="${class}">')
in_span = true
continue
} else if line_t.starts_with('.') && line.ends_with('{') {
//`.header {` => `<div class='header'>`
class := line.find_between('.', '{').trim_space()
trimmed := line.trim_space()
source.write_string(strings.repeat(`\t`, line.len - trimmed.len)) // add the necessary indent to keep <div><div><div> code clean
source.writeln('<div class="${class}">')
continue
} else if line_t.starts_with('#') && line.ends_with('{') {
//`#header {` => `<div id='header'>`
class := line.find_between('#', '{').trim_space()
source.writeln('<div id="${class}">')
continue
} else if line_t == '}' {
source.write_string(strings.repeat(`\t`, line.len - line_t.len)) // add the necessary indent to keep <div><div><div> code clean
if in_span {
source.writeln('</span>')
in_span = false
} else {
source.writeln('</div>')
}
continue
}
}
.js {
// if line.contains('//V_TEMPLATE') {
source.writeln(insert_template_code(fn_name, tmpl_str_start, line, data,
state))
//} else {
// replace `$` to `\$` at first to escape JavaScript template literal syntax
// source.writeln(line.replace(r'$', r'\$').replace(r'$$', r'@').replace(r'.$',
// r'.@').replace(r"'", r"\'"))
//}
continue
}
.css {
// disable template variable declaration in inline stylesheet
// because of some CSS rules prefixed with `@`.
source.writeln(line.replace(r'.$', r'.@').replace(r"'", r"\'"))
continue
}
else {}
}
// by default, just copy 1:1
source.writeln(insert_template_code(fn_name, tmpl_str_start, line, data, state))
}
result := source.str()
$if trace_tmpl_expansion ? {
eprintln('>>>>>>> template expanded to:')
eprintln(result)
eprintln('-----------------------------')
}
return result
}