Parse JSON

Parse JSON breaks one block of text into separate fields, so each value becomes something later steps can pick from. Use it when data arrives as one long block and you need one value inside it, like the customer’s name.

Keyboard shortcut: t+p

How to tell you need it

Open the earlier step’s result. Look for a value sitting inside one long line of text wrapped in braces and quote marks. If the data picker offers you that whole line but not the name inside it, this is the step that opens it up.

It usually comes from one of four places. A webhook that sent its data as text, an app that answered with text rather than named fields, a database column holding JSON, or a .json file you have just read.

Setting it up

1. Press t+p, or open Tools → Data → Convert in the dock and select Parse JSON.
2. In the Input field, select the data reference that contains your JSON string (for example, the response body from a previous HTTP Request step).
3. Save the step.

Glow detects the structure of the parsed JSON automatically. Each field then appears as a selectable output in the data reference picker for downstream steps.

What it passes on

Every value inside becomes its own field on the step, read with the step’s own number in front — 4 in the examples below. Nothing is wrapped.

• A record inside a record is reached with another dot: {{ 4.customer.name }}.
• A list uses the item’s position as the next dot, counting from zero, so {{ 4.items.0.sku }} is the first. Square brackets such as items[0] are not recognised.
• Deeper than that follows the same pattern all the way down: {{ 4.results.2.metadata.tags.0 }}.

Examples to copy

Reading an app’s answer

Suppose an HTTP Request step calls https://api.example.com/orders/12345 and returns the following response body as a string:

{
  "order_id": 12345,
  "customer": {
    "name": "Acme Corp",
    "email": "[email protected]"
  },
  "items": [
    { "sku": "WIDGET-A", "quantity": 10 },
    { "sku": "WIDGET-B", "quantity": 5 }
  ],
  "total": 249.99
}

Say the Parse JSON step is step 4. Each value inside is then its own field, read with this step’s number in front:

You can now use {{ 4.customer.name }} in a Slack message step, or {{ 4.total }} in a Conditions step.

The data picker shows these as customer.name and total, without the step number. That is the label, not the reference. Pick the value from the picker and Glow inserts the full form for you.

Limits

When the text is malformed

If the text is not properly formed JSON, the step fails and the error names what it choked on. Open the earlier step’s Executions tab and read the raw value — that is almost always quicker than guessing which character is wrong.

Where the text comes from a system you do not control and is reliably malformed, put a Code editor step in front to tidy it first.

When nothing arrives

An empty input produces no output, so a later step reading one of these fields finds nothing there and fails. Where the source sometimes sends nothing, put a Conditions step in front testing the input with is not empty.

When it is very large

A very large piece of JSON takes the step longer to read. If you only need a few fields out of it, pull those out with a Code editor step first.

What’s Next?

• Reference the newly exposed fields downstream using the Variable Reference Syntax.
• Review the shapes Glow recognizes in Data Types & Structures.