Mapper

Mapping at a glance

A mapping is itself a document, pairing each target location with the source that fills it:

/citation/title: /title
/citation/doi:
  source: /ids
  find:
    eq: { idType: doi }
    pointer: /value
/citation/authors:
  source: /contributors
  each:
    /family: /surname

Given an input:

{
  "title": "On Mapping",
  "ids": [
    { "idType": "issn", "value": "2049-3630" },
    { "idType": "doi", "value": "10.1000/xyz123" }
  ],
  "contributors": [{ "surname": "Hopper" }, { "surname": "Noether" }]
}

applying the mapping:

import Mapper from '@christiansmith/mapper-js'

const mapper = new Mapper({}, { initializers: {}, transformers: {}, plugins: {} })
const { valid, errors, ...result } = await mapper.map(mapping, input)

produces:

{
  "citation": {
    "title": "On Mapping",
    "doi": "10.1000/xyz123",
    "authors": [{ "family": "Hopper" }, { "family": "Noether" }]
  }
}

Every example in these docs, including this one, is executed against the published implementation as part of the site’s test suite.

Find your way

TutorialsLearning-oriented lessons that take you from installation to a running mapping server.

How-to guidesTask-oriented recipes for problems you already have.

ReferenceInformation-oriented descriptions of every keyword, the context, and the APIs.

ExplanationUnderstanding-oriented discussion of the mapping model and its design.

The family

One language, three published pieces. Mappings written for the engine run unchanged behind the plugin and the server:

mapper-jsThe engine: evaluation and mapping validation. Start at the tutorials.

mapper-requestHTTP fetching as a plugin, with policy fixed at construction.

mapper-httpA standalone image serving mappings over HTTP.

The specificationThe normative source: RFC-style requirements and the conformance suite.