@transformation/ejs

A package for rendering EJS templates.

renderTemplate

Renders an EJS template for each item in the pipeline.

const { renderTemplate } = require("@transformation/ejs");

Let say we want to render stock items with a custom template. Let's start out by defining the template in a file called stocks.ejs.

<%-key%>
<% for(let { price } of items) { -%>
  <%-price%>
<% } -%>

Now we can render items with the template by using the renderTemplate transform.

await expect(
  pipeline(
    emitItems(
      { symbol: "GOOG", price: 1349 },
      { symbol: "AAPL", price: 274 },
      { symbol: "AAPL", price: 275 },
      { symbol: "GOOG", price: 1351 },
      { symbol: "AAPL", price: 279 }
    ),
    groupBy("symbol"),
    renderTemplate("stocks.ejs")
  ),
  "to yield items",
  ["GOOG\n  1349\n  1351\n", "AAPL\n  274\n  275\n  279\n"]
);

writeTemplate

Renders an EJS template for each item in the pipeline to a file.

const { writeTemplate } = require("@transformation/ejs");

Let say we want to render stock items with a custom template. Let's start out by defining the template in a file called stocks.ejs.

<%-key%>
<% for(let { price } of items) { -%>
  <%-price%>
<% } -%>

No we can render items with the template by using the writeTemplate transform.

await program(
  emitItems(
    { symbol: "GOOG", price: 1349 },
    { symbol: "AAPL", price: 274 },
    { symbol: "AAPL", price: 275 },
    { symbol: "GOOG", price: 1351 },
    { symbol: "AAPL", price: 279 }
  ),
  groupBy("symbol"),
  writeTemplate("stocks.ejs", ({ key }) => `stocks-${key}.txt`)
);

This will create two files with the following content.

stocks-APPL.txt:

AAPL: 274
AAPL: 275
AAPL: 279

stocks-GOOG.txt:

GOOG: 1349
GOOG: 1351

You can of cause also just write items to one file, you just needs to make sure to aggregate the pipeline into one item first.

Here we define a template that will render a an array of stocks in a file called stocksArray.ejs.

<% for(let { symbol, price } of items) { -%>
<%-symbol%>: <%-price%>
<% } -%>

await program(
  emitItems(
    { symbol: "GOOG", price: 1349 },
    { symbol: "AAPL", price: 274 },
    { symbol: "AAPL", price: 275 },
    { symbol: "GOOG", price: 1351 },
    { symbol: "AAPL", price: 279 }
  ),
  sortBy("symbol"),
  toArray(),
  writeTemplate("stocksArray.ejs", "stocks.txt")
);

This produce the following result.

stocks.txt:

AAPL: 274
AAPL: 275
AAPL: 279
GOOG: 1349
GOOG: 1351