Quickstart

This page converts the shipped example in both directions, then writes a small mapping of its own, and ends with the same conversion from Go.

Convert the example payload

The repository ships an EnerPlanET calculation payload under examples/. Convert it into a MEME job with the embedded mapping:

t1k -in examples/enerplanet-calculation.json -out meme-job.json

meme-job.json is the body of MEME's POST /simulate. The building and transformer features have become model.nodes (n1, ntrafo_2585, ...), the connections model.transmission arcs (lv_0, mv_2, ...), the annual demands demand_* technologies, the attached PV and battery pv_supply_1 and battery_storage_1, and the transformers model.trade entries that import from the grid. The mapping page explains every field and the identifier scheme.

Convert the job back:

t1k -reverse -in meme-job.json -out calculation.json

calculation.json has the payload's structure again, with EnerPlanET's own ids (1, trafo_2585). Fields a MEME job cannot carry (user_id, callback_url, ...) come back as the placeholders the mapping declares for them; the mapping page lists them.

Write your own mapping

Save the following as orders.json:

{
  "name": "orders-to-invoices",
  "rules": [
    {"from": "order.number", "to": "invoice.reference"},
    {"from": "order.total_cents", "to": "invoice.total", "convert": {"linear": {"divisor": 100}}},
    {"from": "order.placed", "to": "invoice.date", "convert": {"datetime": {"from": "RFC3339", "to": "DateOnly"}}},
    {"to": "invoice.currency", "value": "EUR"},
    {
      "each": {"from": "order.lines[$i]", "to": "invoice.items{line_$i}"},
      "rules": [
        {"from": "sku", "to": "article"},
        {"from": "qty", "to": "quantity", "convert": "number"}
      ]
    }
  ]
}

Run it on an order:

echo '{"order": {"number": "A-17", "total_cents": 1250, "placed": "2026-09-27T10:15:00Z",
       "lines": [{"sku": "bolt", "qty": "40"}, {"sku": "nut", "qty": 40}]}}' \
  | t1k -config orders.json

{
  "invoice": {
    "currency": "EUR",
    "date": "2026-09-27",
    "items": {
      "line_0": {
        "article": "bolt",
        "quantity": 40
      },
      "line_1": {
        "article": "nut",
        "quantity": 40
      }
    },
    "reference": "A-17",
    "total": 12.5
  }
}

The total was divided by 100, the timestamp reduced to a date, the quantity given as text normalised to a number, and the lines keyed by their position. Object keys are written in sorted order; -compact writes the document on one line.

Pipe that output through t1k -config orders.json -reverse and the order comes back:

{
  "order": {
    "lines": [
      {
        "qty": 40,
        "sku": "bolt"
      },
      {
        "qty": 40,
        "sku": "nut"
      }
    ],
    "number": "A-17",
    "placed": "2026-09-27T00:00:00Z",
    "total_cents": 1250
  }
}

The total is in cents again and the items are an array. The date comes back at midnight UTC, because the invoice does not carry the time of day; such losses are the documented exceptions of the reverse direction. currency was a constant for the invoice side only, so the reverse does not write it.

Use it from Go

package main

import (
    "fmt"
    "os"

    "github.com/enerplanet/T1K/pkg/t1k"
)

func main() {
    payload, err := os.ReadFile("examples/enerplanet-calculation.json")
    if err != nil {
        panic(err)
    }
    task := t1k.NewTransformTask(t1k.WithIndent("", "  "))
    job, err := task.Transform(payload)
    if err != nil {
        panic(err)
    }
    fmt.Println(string(job))
}

See Go package for custom configurations, options and error handling.