canvas-lti/utils/jsonConfig.js

A Canvas LTI 1.3 integration tool.

const jsonConfig = (options) => {
    let ltiConfig = {
        title: '',
        description: '',
        scopes: [],
        extensions: [],
        custom_fields: {},
        privacy_level: 'public',
        redirect_uris: [],
        public_jwk_url: `${configuration.baseURL}${configuration.ltiPath}.well-known/jwks.json`,
        target_link_uri: `${configuration.baseURL}${configuration.ltiPath}${configuration.launchPath}`,
        oidc_initiation_url: `${configuration.baseURL}${configuration.ltiPath}oidc`,
        public_jwk: {},
    }
    Object.keys(options).forEach(key => {
        if (key in ltiConfig) {
            switch (key) {
                case 'scopes':
                    if (Array.isArray(options[key])) {
                        for (let i = 0; i < options[key].length; i++) {
                            validScopes = {
                                'create_view_assignment_data': { url: 'https://purl.imsglobal.org/spec/lti-ags/scope/lineitem' },
                                'view_assignment_data': { url: 'https://purl.imsglobal.org/spec/lti-ags/scope/lineitem.readonly' },
                                'view_submission_data': { url: 'https://purl.imsglobal.org/spec/lti-ags/scope/result.readonly' },
                                'create_update_submission_results': { url: 'https://purl.imsglobal.org/spec/lti-ags/scope/score' },
                                'view_progress_records': { url: 'https://canvas.instructure.com/lti-ags/progress/scope/show' },
                                'retrieve_user_data': { url: 'https://purl.imsglobal.org/spec/lti-nrps/scope/contextmembership.readonly' },
                                'update_public_jwk': { url: 'https://canvas.instructure.com/lti/public_jwk/scope/update' },
                                'lookup_account_info': { url: 'https://canvas.instructure.com/doc/api/file.tools_intro.html#:~:text=https%3A//canvas.instructure.com/lti/account_lookup/scope/show' },
                                'view_page_content': { url: 'https://canvas.instructure.com/lti/page_content/show' },
                            };

                            if (Object.keys(validScopes).includes(options[key][i])) {
                                ltiConfig.scopes.push(validScopes[options[key][i]].url);
                            } else {
                                console.warn(`[Canvas-LTI] Ignoring invalid scope: ${options[key][i]}`);
                            }
                        }
                    }
                case 'placements':
                    if (typeof options[key] === 'object' && !Array.isArray(options[key])) {
                        let placement = options[key];

                        if (!placement.title) {
                            console.warn('[Canvas-LTI] Missing title in placement.');
                        }
                        if (!placement.target_link_uri) {
                            console.warn('[Canvas-LTI] Missing target_link_uri in placement.');
                        }
                        if (!placement.type) {
                            console.warn('[Canvas-LTI] Missing type in placement.');
                        }
                        if (!placement.location) {
                            console.warn('[Canvas-LTI] Missing location in placement.');
                        }

                        if (placement.type == 'resource_link') placement.type = 'LtiResourceLinkRequest';
                        if (placement.type == 'deep_link') placement.type = 'LtiDeepLinkingRequest';

                        function isValidURI(uri) {
                            try {
                                new URL(uri);
                                return true;
                            } catch (err) {
                                return false;
                            }
                        }
                        // Check if target_link_uri is a valid URI
                        if (!isValidURI(placement.target_link_uri)) {
                            console.warn('[Canvas-LTI] Invalid target_link_uri:', placement.target_link_uri);
                            return;
                        }


                        let placementObj = {
                            text: placement.title,
                            enabled: placement.enabled ? true : false,
                            icon_url: placement.icon_url ? placement.icon_url : '',
                            placement: placement.location,
                            location: placement.location,
                            message_type: placement.type,
                            target_link_uri: placement.target_link_uri,
                            windowTarget: placement.newTab ? '_blank' : '_self',
                        };


                    }
                    break;

                default:
                    ltiConfig[key] = options[key];
                    break;
            }
        } else {
            console.warn(`[Canvas-LTI] Ignoring JSON option: ${key}`);
        }
    });
}

module.exports = jsonConfig;