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[
	{
		"id": "_:label",
		"type": "label",
		"key": "http://underlay.org/ns/label",
		"value": "_:label-value"
	},
	{
		"id": "_:label-value",
		"type": "product",

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export const zip = <A, B>(
	a: Iterable<A>,
	b: Iterable<B>
): Iterable<[A, B]> => ({
	[Symbol.iterator]() {
		const iterA = a[Symbol.iterator]()
		const iterB = b[Symbol.iterator]()
		return {
			next() {
				const resultA = iterA.next()

joeltg

Package Server HTTP API

A package server exposes a REST HTTP API for managing Underlay resources.

• Assertions are arbitrary RDF datasets
• Files are arbitrary byte arrays, with a single explicit MIME type and a known integer size in bytes
• Packages are a kind of container analogous to a directory or a Git repository. Packages have metadata like schemas and provenance and contain assertions, files, and other packages.

Like all REST services, package servers implicitly distinguish between abstract resources and concrete representations. A resource is a conceptual target identified by a URL; a representation of a resource is a physical materialization in some known format of a version of that resource at a point in time. The REST API interfaces between the two, resolving requests for resources into concrete representations.

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import * as t from "io-ts/lib/index"
import { isRight, Right } from "fp-ts/lib/Either"

const rdfType = t.literal("http://www.w3.org/1999/02/22-rdf-syntax-ns#type")

type Predicate = t.StringC | typeof rdfType
type ShapeExpr = t.Type<shapeExpr>
type ValueExpr = ShapeExpr | typeof Singular
type Cardinality = t.NumberC | t.LiteralC<1>

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PREFIX u: <http://underlay.mit.edu/ns#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
PREFIX ldp: <http://www.w3.org/ns/ldp#>
PREFIX prov: <http://www.w3.org/ns/prov#>
PREFIX dcterms: <http://purl.org/dc/terms/>

start = bnode {
  a [ u:Package ] ;
  ldp:hasMemberRelation [ prov:hadMember ] ;
  $_:resource ldp:membershipResource iri ;

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declare module "@shexjs/parser" {
	function construct(): Parser

	interface Parser {
		parse(shex: string): Schema
	}

	type Schema = {
		"@context"?: "http://www.w3.org/ns/shex.jsonld"
		type: "Schema"

joeltg

Background

Suppose we have a collection of RDF graphs (directed labelled multigraphs, possibly cyclic, nodes are identified by their label, node labels are URIs or RDF Literals, edge labels are URIs typically taken from one of a few well-known vocabularies) and let's call that structure a Package. Packages entail a natural "union" graph of their own where we merge the graphs by considering nodes with the same label to be the same node.

(background on the RDF data model as needed: primer, syntax, semantics)

We want people to be able to publish arbitrary graph data, but we also imagine people using packages to publish relatively structured data (like a relational table) and everything in-between (like a relational table annotated with arbitrary graph data). So we want to let packages optionally carry some metadata where they can define some schemas and list the nodes in the package that valida

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type Container<T> = T | T[]
type RecursiveContainer<T> = T | RecursiveArray<T>
interface RecursiveArray<T> extends Array<RecursiveContainer<T>> {}

declare namespace JsonLd {
	export type Graph = Container<Node>

	export type Node = {
		"@id"?: string
		"@type"?: Container<string>

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{
	"mappings": {
		"doc": {
			"properties": {
				"text": { "type": "text" },
				"title": { "type": "text" },
				"fileUrl": { "type": "keyword" },
				"organizationId": { "type": "keyword" },
				"uploadDate": { "type": "date" },
				"publicationDate": { "type": "date" },

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{
	"dc": "http://purl.org/dc/elements/1.1/",
	"dcterms": "http://purl.org/dc/terms/",
	"Iptc4xmpCore": "http://iptc.org/std/Iptc4xmpCore/1.0/xmlns/",
	"Iptc4xmpExt": "http://iptc.org/std/Iptc4xmpExt/2008-02-29/",
	"plus": "http://ns.useplus.org/ldf/xmp/1.0/",
	"cp": "http://schemas.openxmlformats.org/package/2006/metadata/core-properties/",
	"extended-properties": "http://schemas.openxmlformats.org/officeDocument/2006/extended-properties/",
	"photoshop": "http://ns.adobe.com/photoshop/1.0/",
	"xmp": "http://ns.adobe.com/xap/1.0/",