const { BagItProfile } = require('./bagit_profile');
const { BagItProfileInfo } = require('./bagit_profile_info');
const { Constants } = require('../core/constants');
const { Context } = require('../core/context');
const { TagDefinition } = require('./tag_definition');
/**
* BagItUtil contains some static utility functions to help with BagIt profiles.
*/
class BagItUtil {
/**
* This function converts a standard BagIt profile, like the ones
* described at https://github.com/bagit-profiles/bagit-profiles
* into a DART BagIt profile.
*
* @see {@link profileFromStandardObject}
* @see {@link https://github.com/bagit-profiles/bagit-profiles|Standard BagIt Profiles}
*
* @param {string} jsonString - The raw JSON BagIt profile to convert.
* @returns {BagItProfile} - A DART BagItProfile object.
*/
static profileFromStandardJson(jsonString) {
var obj = JSON.parse(jsonString)
return BagItUtil.profileFromStandardObject(obj)
}
/**
* This function converts a standard BagIt profile object, like the ones
* described at https://github.com/bagit-profiles/bagit-profiles
* into a DART BagIt profile.
*
* If you want to convert a standard profile directly from a JSON string,
* see {@link profileFromStandardJson}.
*
* @see {@link profileFromStandardJson}
* @see {@link https://github.com/bagit-profiles/bagit-profiles|Standard BagIt Profiles}
*
* @param {Object} obj - The BagIt profile to convert.
* @returns {BagItProfile} - A DART BagItProfile object.
*
*/
static profileFromStandardObject(obj) {
if (BagItUtil.guessProfileType(obj) != 'bagit_profiles') {
throw Context.y18n.__("Object does not look like a BagIt profile");
}
var p = new BagItProfile();
p.name = obj["BagIt-Profile-Info"]["External-Description"];
p.description = Context.y18n.__("Imported from %s", obj["BagIt-Profile-Info"]["BagIt-Profile-Identifier"]);
p.acceptBagItVersion = obj["Accept-BagIt-Version"];
p.acceptSerialization = obj["Accept-Serialization"];
p.allowFetchTxt = obj["Allow-Fetch.txt"];
p.serialization = obj["Serialization"];
p.manifestsRequired = obj["Manifests-Required"];
p.manifestsAllowed = obj["Manifests-Allowed"] || Constants.DIGEST_ALGORITHMS;
p.tagManifestsRequired = obj["Tag-Manifests-Required"] || [];
p.tagManifestsAllowed = obj["Tag-Manifests-Allowed"] || Constants.DIGEST_ALGORITHMS;
p.tagFilesAllowed = obj["Tag-Files-Allowed"] || ["*"];
p.bagItProfileInfo = new BagItProfileInfo();
p.bagItProfileInfo.bagItProfileIdentifier = obj["BagIt-Profile-Info"]["BagIt-Profile-Identifier"];
p.bagItProfileInfo.bagItProfileVersion = obj["BagIt-Profile-Info"]["BagIt-Profile-Version"];
p.bagItProfileInfo.contactEmail = obj["BagIt-Profile-Info"]["Contact-Email"];
p.bagItProfileInfo.contactName = obj["BagIt-Profile-Info"]["Contact-Name"];
p.bagItProfileInfo.externalDescription = obj["BagIt-Profile-Info"]["External-Description"];
p.bagItProfileInfo.sourceOrganization = obj["BagIt-Profile-Info"]["Source-Organization"];
p.bagItProfileInfo.version = obj["BagIt-Profile-Info"]["Version"];
// Copy required tag definitions to our preferred structure.
// The BagIt profiles we're transforming don't have default
// values for tags.
//
// What if there are entries other than Bag-Info?
// See https://trello.com/c/SBLvoiwK
for (var tagName of Object.keys(obj["Bag-Info"])) {
var tagDef;
var tag = obj["Bag-Info"][tagName]
let tagsFromProfile = p.findMatchingTags("tagName", tagName).filter(t => t.tagFile = "bag-info.txt");
if (tagsFromProfile.length > 0) {
tagDef = tagsFromProfile[0];
} else {
tagDef = new TagDefinition({
tagFile: "bag-info.txt",
tagName: tagName
});
p.tags.push(tagDef);
}
tagDef.required = tag["required"] || false;
tagDef.values = tag["values"] || [];
tagDef.defaultValue = tag["defaultValue"] || null;
if (Array.isArray(tag["values"]) && tag["values"].length == 1) {
tagDef.defaultValue = tag["values"][0];
}
}
return p;
}
/**
* This function tries to guess the type of BagIt Profile based on
* the keys in the profile object. Returns one of the following:
*
* * "bagit_profiles" - This profile is of the type described
* in the [bagit-profiles](https://github.com/bagit-profiles/bagit-profiles) GitHub repo.
* * "loc_unordered" - This is an unordered Library of Congress
* profile, like the example at [other-project-profile.json](https://github.com/LibraryOfCongress/bagger/blob/master/bagger-business/src/main/resources/gov/loc/repository/bagger/profiles/other-project-profile.json)
* * "loc_ordered" - An ordered Library of Congress profile, like the
* [SANC State Profile](https://github.com/LibraryOfCongress/bagger/blob/master/bagger-business/src/main/resources/gov/loc/repository/bagger/profiles/SANC-state-profile.json)
* * "dart" - A DART BagIt profile, like the [APTrust BagIt Profile](https://github.com/APTrust/dart/blob/master/profiles/aptrust_2.2.json)
* * "unknown" - Cannot identify profile type.
*
* The great thing about standards is that there are so many of them.
*
* @param {object}
* @returns {string}
*
*/
static guessProfileType(obj) {
let type = 'unknown';
if (Array.isArray(obj['tags'])) {
type = 'dart';
} else if (Array.isArray(obj['ordered'])) {
type = 'loc_ordered';
} else if (typeof obj['Bag-Info'] == 'object') {
type = 'bagit_profiles'
} else {
let everythingLooksLikeATag = true;
for (let item of Object.values(obj)) {
// Tags have at least one of these properties.
if (item['fieldRequired'] === undefined && item['requiredValue'] === undefined) {
everythingLooksLikeATag = false;
break;
}
}
if (everythingLooksLikeATag) {
type = 'loc_unordered'
}
}
return type;
}
/**
* Converts an ordered Library of Congress BagIt profile like the
* [SANC-state-profile.json](https://raw.githubusercontent.com/LibraryOfCongress/bagger/master/bagger-business/src/main/resources/gov/loc/repository/bagger/profiles/SANC-state-profile.json)
* profile to a DART BagIt profile.
*
* @param {object} - The profile to import.
* @param {string} - Optional URL from which profile was imported.
* @returns {BagItProfile}
*/
static profileFromLOCOrdered(obj, sourceUrl) {
if (BagItUtil.guessProfileType(obj) != 'loc_ordered') {
throw Context.y18n.__("Object does not look like an ordered Library of Congress BagIt profile");
}
var dartProfile = new BagItProfile();
dartProfile.name = BagItUtil._getProfileName(sourceUrl);
dartProfile.description = dartProfile.name;
for (let item of obj['ordered']) {
let tagName = Object.keys(item)[0];
let tagObj = Object.values(item)[0];
BagItUtil.convertLOCTag(dartProfile, tagName, tagObj);
}
return dartProfile;
}
/**
* Converts an unordered Library of Congress BagIt profile like the
* [other-project-profile.json](https://raw.githubusercontent.com/LibraryOfCongress/bagger/master/bagger-business/src/main/resources/gov/loc/repository/bagger/profiles/other-project-profile.json)
* profile to a DART BagIt profile.
*
* @param {object}
* @param {string} - Optional URL from which profile was imported.
* @returns {BagItProfile}
*/
static profileFromLOC(obj, sourceUrl) {
if (BagItUtil.guessProfileType(obj) != 'loc_unordered') {
throw Context.y18n.__("Object does not look like an unordered Library of Congress BagIt profile");
}
var dartProfile = new BagItProfile();
dartProfile.name = BagItUtil._getProfileName(sourceUrl);
dartProfile.description = dartProfile.name;
for (let [tagName, tagObj] of Object.entries(obj)) {
BagItUtil.convertLOCTag(dartProfile, tagName, tagObj);
}
return dartProfile;
}
static convertLOCTag(dartProfile, tagName, locTag) {
let tagDef;
let tagsFromProfile = dartProfile.findMatchingTags("tagName", tagName).filter(t => t.tagFile = "bag-info.txt");
if (tagsFromProfile.length > 0) {
tagDef = tagsFromProfile[0];
} else {
tagDef = new TagDefinition({
tagFile: "bag-info.txt",
tagName: tagName
});
dartProfile.tags.push(tagDef);
}
tagDef.required = locTag["fieldRequired"] || false;
tagDef.values = locTag["valueList"] || [];
tagDef.defaultValue = locTag["defaultValue"] || null;
if (locTag["requiredValue"]) {
tagDef.required = true;
tagDef.values = [locTag["requiredValue"]];
tagDef.defaultValue = locTag["requiredValue"];
}
}
/**
* This returns a name and description for an imported profile.
* This is not necessary for profiles conforming to
* https://github.com/bagit-profiles/bagit-profiles/, but it is
* useful for Library of Congress profiles.
*
* If sourceUrl is supplied, this returns a profile name
* based on the file name at the end of the url. For example,
* if sourceUrl is https://example.com/basic_profile.json,
* this returns "Profile imported from https://example.com/basic_profile.json".
* Otherwise, it returns "Imported Profile <datestamp>"
*
* @param {string}
* @returns {string}
*/
static _getProfileName(sourceUrl) {
var now = new Date();
let name = Context.y18n.__("Imported Profile %s", now.toISOString());
if (sourceUrl) {
name = Context.y18n.__("Profile imported from %s", sourceUrl);
}
return name;
}
/**
* This function converts a DART BagItProfile object to the format
* described at https://github.com/bagit-profiles/bagit-profiles.
*
* Note that a considerable amount of tag-related information
* will be lost in the conversion, since the GitHub BagIt profiles
* do not support as rich a set of information as DART profiles.
*
* @see {@link https://github.com/bagit-profiles/bagit-profiles|Standard BagIt Profiles}
*
* @param {BagItProfile} - A DART BagItProfile object.
* @returns {Object} - A converted BagIt profile.
*
*/
static profileToStandardObject(p) {
var obj = {};
obj["Accept-BagIt-Version"] = p.acceptBagItVersion;
obj["Accept-Serialization"] = p.acceptSerialization;
obj["Allow-Fetch.txt"] = p.allowFetchTxt;
obj["Serialization"] = p.serialization;
obj["Manifests-Allowed"] = p.manifestsAllowed;
obj["Tag-Manifests-Allowed"] = p.tagManifestsAllowed;
obj["Manifests-Required"] = p.manifestsRequired;
obj["Tag-Manifests-Required"] = p.tagManifestsRequired;
obj["Manifests-Allowed"] = p.manifestsAllowed;
obj["Tag-Manifests-Allowed"] = p.tagManifestsAllowed;
obj["Tag-Files-Allowed"] = p.tagFilesAllowed;
obj["BagIt-Profile-Info"] = {};
obj["BagIt-Profile-Info"]["BagIt-Profile-Identifier"] = p.bagItProfileInfo.bagItProfileIdentifier;
obj["BagIt-Profile-Info"]["BagIt-Profile-Version"] = p.bagItProfileInfo.bagItProfileVersion;
obj["BagIt-Profile-Info"]["Contact-Email"] = p.bagItProfileInfo.contactEmail;
obj["BagIt-Profile-Info"]["Contact-Name"] = p.bagItProfileInfo.contactName;
obj["BagIt-Profile-Info"]["External-Description"] = p.bagItProfileInfo.externalDescription;
obj["BagIt-Profile-Info"]["Source-Organization"] = p.bagItProfileInfo.sourceOrganization;
obj["BagIt-Profile-Info"]["Version"] = p.bagItProfileInfo.version;
// Tags
obj["Bag-Info"] = {};
obj["Tag-Files-Required"] = [];
for (let tagDef of p.tags) {
if (tagDef.tagFile == "bagit.txt") {
continue;
}
if (tagDef.tagFile == "bag-info.txt") {
obj["Bag-Info"][tagDef.tagName] = {};
obj["Bag-Info"][tagDef.tagName]["required"] = tagDef.required;
if (Array.isArray(tagDef.values) && tagDef.values.length) {
obj["Bag-Info"][tagDef.tagName]["values"] = tagDef.values;
}
} else {
// We can't specify tag info outside of bag-info.txt,
// but if we find a required tag in another file,
// we can assume that tag file is required.
if (tagDef.required === true && !obj["Tag-Files-Required"].includes(tagDef.tagFile)) {
obj["Tag-Files-Required"].push(tagDef.tagFile);
}
}
}
return obj;
}
/**
* This function converts a DART BagItProfile object to a JSON string
* in the format described at
* https://github.com/bagit-profiles/bagit-profiles.
*
* Note that a considerable amount of tag-related information
* will be lost in the conversion, since the GitHub BagIt profiles
* do not support as rich a set of information as DART profiles.
*
* @see {@link https://github.com/bagit-profiles/bagit-profiles|Standard BagIt Profiles}
*
* @param {BagItProfile} - A DART BagItProfile object.
* @returns {string}
*
*/
static profileToStandardJson(profile) {
return JSON.stringify(BagItUtil.profileToStandardObject(profile), null, 2);
}
}
module.exports.BagItUtil = BagItUtil;