Extremely Popular
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164const { open, Buffer } = Deno;type Reader = Deno.Reader;import { stringsReader } from 'https://deno.land/std/io/util.ts';import { BufReader } from 'https://deno.land/std/io/bufio.ts';import escape from 'https://deno.land/x/lodash/escape.js';
export interface Params { [key: string]: any;}
enum ReadMode { Normal, Escaped, Raw, Comment, Evaluate,}
enum Codes { Begin = 60, // < End = 62, // > Percent = 37, // % Escaped = 61, // = Raw = 45, // - Comment = 35, // #}
interface Template { (params: Params): Promise<Reader>;}
async function include(path: string, params: Params): Promise<string> { const result = await renderFile(path, params); const buf = new Buffer(); await buf.readFrom(result); return buf.toString();}
function NewTemplate(script: string): Template { return async (params: Params): Promise<Reader> => { const output: Array<string> = []; await new Promise(resolve => { const $$CONSTANTS = { ...params, include, $$OUTPUT: output, $$FINISHED: resolve, $$ESCAPE: escape, }; const header = Object.keys($$CONSTANTS) .map(k => `const ${k} = $$CONSTANTS.${k};`) .join('\n'); const src = `(async() => { ${header} ${script} $$FINISHED(); })();`; eval(src); }); return stringsReader(output.join('')); };}
export async function compile(reader: Reader): Promise<Template> { const src = new BufReader(reader); const buf: Array<number> = []; const statements: Array<string> = []; const statementBuf = new Buffer(); let readMode: ReadMode = ReadMode.Normal; const statementBufWrite = async (byte: number): Promise<number> => await statementBuf.write(new Uint8Array([byte]));
while (true) { const byte = await src.readByte(); if (byte === Deno.EOF) { break; }
buf.push(byte); if (buf.length < 3) { continue; }
if (readMode === ReadMode.Normal) { // Detect ReadMode if (buf[0] === Codes.Begin && buf[1] === Codes.Percent) { switch (buf[2]) { case Codes.Escaped: readMode = ReadMode.Escaped; break; case Codes.Raw: readMode = ReadMode.Raw; break; case Codes.Comment: readMode = ReadMode.Comment; break; default: readMode = ReadMode.Evaluate; break; } statements.push(`$$OUTPUT.push(\`${statementBuf.toString()}\`);`); statementBuf.reset(); buf.splice(0); continue; } if (buf.length > 2) { await statementBufWrite(buf.shift() as number); } continue; }
// Finish current ReadMode if (buf[1] === Codes.Percent && buf[2] === Codes.End) { statementBufWrite(buf.shift() as number); buf.splice(0); // Don't execute if ReadMode is Comment. if (readMode !== ReadMode.Comment) { switch (readMode) { case ReadMode.Raw: statements.push(`$$OUTPUT.push(${statementBuf.toString()});`); break; case ReadMode.Escaped: statements.push( `$$OUTPUT.push($$ESCAPE(${statementBuf.toString()}));` ); break; case ReadMode.Evaluate: statements.push(statementBuf.toString()); break; } } statementBuf.reset(); readMode = ReadMode.Normal; continue; } await statementBufWrite(buf.shift() as number); }
// Flush buffer while (buf.length > 0) { await statementBufWrite(buf.shift() as number); } statements.push(`$$OUTPUT.push(\`${statementBuf.toString()}\`);`); statementBuf.reset();
return await NewTemplate(statements.join(''));}
export async function render(body: string, params: Params): Promise<Reader> { const reader = stringsReader(body); const template = await compile(reader); return template(params);}
export async function renderFile( path: string, params: Params): Promise<Reader> { const file = await open(path); const template = await compile(file); file.close(); return template(params);}