improve backend handler design

src/backends/backends.js

@@ -54,17 +54,39 @@ class BACKEND {
 	}
 }
 
+export class AtomicChange {
+	constructor (valid, delta, callback, status = { ok: true, status: 200, message: "" }) {
+		this.valid = valid;
+		this.delta = delta;
+		this.callback = callback;
+		this.status = status;
+	}
+
+	/**
+	 * Execute the change using the saved delta using the callback function
+	 */
+	async commit () {
+		const res = await this.callback(this.delta);
+		return res;
+	}
+}
+
+export function doNothingCallback (delta) {
+	return { ok: true, status: 200, message: "" };
+}
+
 /**
  * Interface for backend types that store/interact with user & group data.
  * Not all backends need to implement all interface methods.
  */
 class USER_BACKEND extends BACKEND {
 	/**
-	 * Add user to backend
+	 * Validate an add user operation with the following parameters.
+	 * Returns whether the change is valid and a delta object to be used in the operation.
 	 * @param {{id: string, realm: string}} user
 	 * @param {Object} attributes user attributes
 	 * @param {Object} params authentication params, usually req.cookies
-	 * @returns {{ok: boolean, status: number, message: string}} error object or null
+	 * @returns {AtomicChange} atomic change object
 	 */
 	addUser (user, attributes, params) {}
 
@@ -84,28 +106,31 @@ class USER_BACKEND extends BACKEND {
 	getAllUsers (params) {}
 
 	/**
-	 * Modify user in backend
+	 * Validate a set user operation with the following parameters.
+	 * Returns whether the change is valid and a delta object to be used in the operation.
 	 * @param {{id: string, realm: string}} user
 	 * @param {Object} attributes new user attributes to modify
 	 * @param {Object} params authentication params, usually req.cookies
-	 * @returns {{ok: boolean, status: number, message: string}} error object or null
+	 * @returns {AtomicChange} atomic change object
 	 */
 	setUser (user, attributes, params) {}
 
 	/**
-	 * Delete user from backend
+	 * Validate a delete user operation with the following parameters.
+	 * Returns whether the change is valid and a delta object to be used in the operation.
 	 * @param {{id: string, realm: string}} user
 	 * @param {Object} params authentication params, usually req.cookies
-	 * @returns {{ok: boolean, status: number, message: string}} error object or null
+	 * @returns {AtomicChange} atomic change object
 	 */
 	delUser (user, params) {}
 
 	/**
-	 * Add group to backend
+	 * Validate an add group operation with the following parameters.
-	 * @param {{id: string}} group
+	 * Returns whether the change is valid and a delta object to be used in the operation.
+	 * @param {{id: string, realm: string}} group
 	 * @param {Object} attributes group attributes
 	 * @param {Object} params authentication params, usually req.cookies
-	 * @returns {{ok: boolean, status: number, message: string}} error object or null
+	 * @returns {AtomicChange} atomic change object
 	 */
 	addGroup (group, attributes, params) {}
 
@@ -125,37 +150,40 @@ class USER_BACKEND extends BACKEND {
 	getAllGroups (params) {}
 
 	/**
-	 * Modify group in backend
+	 * Validate a set group operation with the following parameters.
-	 * @param {{id: string}} group
+	 * Returns whether the change is valid and a delta object to be used in the operation.
-	 * @param {Object} attributes new group attributes to modify
+	 * @param {{id: string, realm: string}} group
+	 * @param {Object} attributes group attributes
 	 * @param {Object} params authentication params, usually req.cookies
-	 * @returns {{ok: boolean, status: number, message: string}} error object or null
+	 * @returns {AtomicChange} atomic change object
 	 */
 	setGroup (group, attributes, params) {}
-
 	/**
-	 * Delete group from backend
+	 * Validate a del group operation with the following parameters.
-	 * @param {{id: string}} group
+	 * Returns whether the change is valid and a delta object to be used in the operation.
+	 * @param {{id: string, realm: string}} group
 	 * @param {Object} params authentication params, usually req.cookies
-	 * @returns {{ok: boolean, status: number, message: string}} error object or null
+	* @returns {AtomicChange} atomic change object
 	 */
-	delGroup (group, params) {}
+	delGroup (group, attributes, params) {}
 
 	/**
-	 * Add user to group
+	 * Validate an add user to group operation with the following parameters.
+	 * Returns whether the change is valid and a delta object to be used in the operation.
 	 * @param {{id: string, realm: string}} user
 	 * @param {{id: string}} group
 	 * @param {Object} params authentication params, usually req.cookies
-	 * @returns {{ok: boolean, status: number, message: string}} error object or null
+	 * @returns {AtomicChange} atomic change object
 	 */
 	addUserToGroup (user, group, params) {}
 
 	/**
-	 * Remove user from group
+	 * Validate a remove user from group operation with the following parameters.
+	 * Returns whether the change is valid and a delta object to be used in the operation.
 	 * @param {{id: string, realm: string}} user
 	 * @param {{id: string}} group
 	 * @param {Object} params authentication params, usually req.cookies
-	 * @returns {{ok: boolean, status: number, message: string}} error object or null
+	* @returns {AtomicChange} atomic change object
 	 */
 	delUserFromGroup (user, group, params) {}
 }
@@ -218,20 +246,30 @@ class USER_BACKEND_MANAGER extends USER_BACKEND {
 	}
 
 	async setUser (user, attributes, params) {
-		const results = {
+		const atomicChanges = [];
+		for (const backend of this.#config.realm[user.realm]) {
+			const atomicChange = await global.backends[backend].setUser(user, attributes, params);
+			if (atomicChange.valid === false) { // if any fails, preemptively exit
+				return atomicChange.stauts;
+			}
+			atomicChanges.push(atomicChange); // queue callback into array
+		}
+		const response = {
 			ok: true,
 			status: 200,
-			message: ""
+			message: "",
+			allResponses: []
 		};
-		for (const backend of this.#config.realm[user.realm]) {
+		for (const atomicChange of atomicChanges) {
-			const result = await global.backends[backend].setUser(user, attributes, params);
+			const atomicResponse = await atomicChange.commit();
-			if (!result) {
+			if (atomicResponse.ok === false) {
-				results.ok = false;
+				response.ok = false;
-				results.status = 500;
+				response.status = atomicResponse.status;
-				return results;
+				response.message = atomicResponse.message;
 			}
+			response.allResponses.push(); // execute callback
 		}
-		return results;
+		return response;
 	}
 
 	delUser (user, params) {}

src/backends/localdb.js

@@ -1,6 +1,6 @@
 import { readFileSync, writeFileSync } from "fs";
 import { exit } from "process";
-import { DB_BACKEND } from "./backends.js";
+import { AtomicChange, DB_BACKEND, doNothingCallback } from "./backends.js";
 
 export default class LocalDB extends DB_BACKEND {
 	#path = null;
@@ -35,22 +35,7 @@ export default class LocalDB extends DB_BACKEND {
 		writeFileSync(this.#path, JSON.stringify(this.#data));
 	}
 
-	addUser (user, attributes, params) {
+	addUser (user, attributes, params) {}
-		const username = `${user.id}@${user.realm}`;
-		if (this.#data.users[username]) { // user already exists
-			return {
-				ok: false,
-				status: 1,
-				message: "User already exists"
-			};
-		}
-		else {
-			attributes = attributes || this.#defaultuser;
-			this.#data.users[username] = attributes;
-			this.#save();
-			return null;
-		}
-	}
 
 	getUser (user, params) {
 		const requestedUser = `${user.id}@${user.realm}`;
@@ -76,33 +61,42 @@ export default class LocalDB extends DB_BACKEND {
 	}
 
 	setUser (user, attributes, params) {
-		if (attributes.resources && attributes.cluster && attributes.templates) { // localdb should only deal with these attributes
+		if (attributes.resources && attributes.cluster && attributes.templates) {
 			const username = `${user.id}@${user.realm}`;
 			if (this.#data.users[username]) {
-				this.#data.users[username] = attributes;
+				if (this.#data.users[params.username] && this.#data.users[params.username].cluster.admin) {
+					return new AtomicChange(false,
+						{
+							username,
+							attributes: {
+								resources: attributes.resources,
+								cluster: attributes.cluster,
+								templates: attributes.templates
+							}
+						},
+						(delta) => {
+							this.#data.users[delta.username] = delta.attributes;
 							this.#save();
-				return true;
+							return { ok: true, status: 200, message: "" };
+						},
+						{ ok: true, status: 200, message: "" }
+					);
 				}
 				else {
-				return false;
+					return new AtomicChange(false, {}, doNothingCallback, { ok: false, status: 401, message: `${params.username} is not an admin user in localdb` });
 				}
 			}
-		else { // if request is not setting these attributes, then assume its fine but do nothing
+			else {
-			return true;
+				// return false;
+				return new AtomicChange(false, {}, doNothingCallback, { ok: false, status: 400, message: `${username} was not found in localdb` });
+			}
+		}
+		else {
+			return new AtomicChange(true, {}, doNothingCallback, null);
 		}
 	}
 
-	delUser (user, params) {
+	delUser (user, params) {}
-		const username = `${user.id}@${user.realm}`;
-		if (this.#data.users[username]) {
-			delete this.#data.users[username];
-			this.#save();
-			return true;
-		}
-		else {
-			return false;
-		}
-	}
 
 	// group methods not implemented because db backend does not store groups
 	addGroup (group, atrributes, params) {}
@@ -115,26 +109,8 @@ export default class LocalDB extends DB_BACKEND {
 	delGroup (group, params) {}
 
 	// assume that adding to group also adds to group's pool
-	addUserToGroup (user, group, params) {
+	addUserToGroup (user, group, params) {}
-		const username = `${user.id}@${user.realm}`;
-		if (this.#data.users[username]) {
-			this.#data.users[username].cluster.pools[group.id] = true;
-			return true;
-		}
-		else {
-			return false;
-		}
-	}
 
 	// assume that adding to group also adds to group's pool
-	delUserFromGroup (user, group, params) {
+	delUserFromGroup (user, group, params) {}
-		const username = `${user.id}@${user.realm}`;
-		if (this.#data.users[username] && this.#data.users[username].cluster.pools[group.id]) {
-			delete this.#data.users[username].cluster.pools[group.id];
-			return true;
-		}
-		else {
-			return false;
-		}
-	}
 }

src/backends/paasldap.js

@@ -1,5 +1,5 @@
 import axios from "axios";
-import { AUTH_BACKEND } from "./backends.js";
+import { AtomicChange, AUTH_BACKEND, doNothingCallback } from "./backends.js";
 import * as setCookie from "set-cookie-parser";
 
 export default class PAASLDAP extends AUTH_BACKEND {
@@ -48,17 +48,12 @@ export default class PAASLDAP extends AUTH_BACKEND {
 	}
 
 	#handleGenericReturn (res) {
-		if (res.ok) { // if ok, return null
-			return null;
-		}
-		else { // if not ok, return error obj
 		return {
 			ok: res.ok,
 			status: res.status,
 			message: res.ok ? "" : res.data.error
 		};
 	}
-	}
 
 	async openSession (user, password) {
 		const username = user.id;
@@ -86,10 +81,7 @@ export default class PAASLDAP extends AUTH_BACKEND {
 		}
 	}
 
-	async addUser (user, attributes, params) {
+	async addUser (user, attributes, params) {}
-		const res = await this.#request(`/users/${user.id}`, "POST", params, attributes);
-		return this.#handleGenericReturn(res);
-	}
 
 	async getUser (user, params) {
 		if (!params) { // params required, do nothing if params are missing
@@ -124,19 +116,37 @@ export default class PAASLDAP extends AUTH_BACKEND {
 	}
 
 	async setUser (user, attributes, params) {
-		const res = await this.#request(`/users/${user.id}`, "POST", params, attributes);
+		if (!attributes.userpassword && !attributes.cn && attributes.sn) {
+			return new AtomicChange(true, {}, doNothingCallback, null); // change has no ldap attributes
+		}
+		const ldapAttributes = {};
+		if (attributes.userpassword) {
+			ldapAttributes.userpassword = attributes.userpassword;
+		}
+		if (attributes.cn) {
+			ldapAttributes.cn = attributes.cn;
+		}
+		if (attributes.sn) {
+			ldapAttributes.sn = attributes.sn;
+		}
+		return new AtomicChange(
+			true,
+			{
+				user,
+				ldapAttributes,
+				params
+			},
+			async (delta) => {
+				const res = await this.#request(`/users/${delta.user.id}`, "POST", delta.params, delta.ldapAttributes);
 				return this.#handleGenericReturn(res);
+			},
+			{ ok: true, status: 200, message: "" }
+		);
 	}
 
-	async delUser (user, params) {
+	async delUser (user, params) {}
-		const res = await this.#request(`/users/${user.id}`, "DELETE", params);
-		return this.#handleGenericReturn(res);
-	}
 
-	async addGroup (group, attributes, params) {
+	async addGroup (group, attributes, params) {}
-		const res = await this.#request(`/groups/${group.id}`, "POST", params);
-		return this.#handleGenericReturn(res);
-	}
 
 	async getGroup (group, params) {
 		return await this.#request(`/groups/${group.id}`, "GET", params);
@@ -163,21 +173,12 @@ export default class PAASLDAP extends AUTH_BACKEND {
 
 	async setGroup (group, attributes, params) {
 		// not implemented, LDAP groups do not have any attributes to change
-		return null;
+		return new AtomicChange(true, {}, doNothingCallback, null); ;
 	}
 
-	async delGroup (group, params) {
+	async delGroup (group, params) {}
-		const res = await this.#request(`/groups/${group.id}`, "DELETE", params);
-		return this.#handleGenericReturn(res);
-	}
 
-	async addUserToGroup (user, group, params) {
+	async addUserToGroup (user, group, params) {}
-		const res = await this.#request(`/groups/${group.id}/members/${user.id}`, "POST", params);
-		return this.#handleGenericReturn(res);
-	}
 
-	async delUserFromGroup (user, group, params) {
+	async delUserFromGroup (user, group, params) {}
-		const res = await this.#request(`/groups/${group.id}/members/${user.id}`, "DELETE", params);
-		return this.#handleGenericReturn(res);
-	}
 }