401 error accessing Cloudant from IBM Cloud Function

Question

I have created a Cloudant service and credentials (1) along with a database and a couple of documents. I want to access that database from an IBM Cloud Function so created a function to do that. I tested the function by adding the copied and pasted credentials from (1) into the "Invoke with credentials" box (along with the and the db name and a valid docid). The function seems to take all that info correctly but I get a 401 error... any help would be massively appreciated!

{
  "error": {
    "description": "couch returned 401",
    "errid": "non_200",
    "error": "unauthorized",
    "headers": {
      "cache-control": "must-revalidate",
      "content-type": "application/json",
      "date": "Sat, 30 May 2020 16:37:25 GMT",
      "statusCode": 401,
      "strict-transport-security": "max-age=31536000",
      "uri": "xxxxxxx",
      "via": "1.1 lb1.bm-cc-eu-gb-04 (Glum/1.89.6)",
      "www-authenticate": "Basic realm=\"Cloudant Private Database\"",
      "x-cloudant-action": "cloudantnosqldb.any-document.read",
      "x-cloudant-backend": "bm-cc-eu-gb-04",
      "x-cloudant-request-class": "lookup",
      "x-content-type-options": "nosniff",
      "x-couch-request-id": "03e7fe91bb"
    },
    "message": "_reader access is required for this request",
    "name": "Error",
    "reason": "_reader access is required for this request",
    "request": {
      "headers": {
        "accept": "application/json",
        "content-type": "application/json"
      },
      "method": "GET",
      "uri": "xxxxx"
    },
    "scope": "couch",
    "stack": "Error: _reader access is required for this request\n    at Object.clientCallback (/node_modules/@cloudant/cloudant/node_modules/nano/lib/nano.js:151:15)\n    at Request._callback (/node_modules/@cloudant/cloudant/lib/clientutils.js:162:11)\n    at Request.self.callback (/node_modules/request/request.js:185:22)\n    at Request.emit (events.js:198:13)\n    at Request.self._source.emit (/node_modules/@cloudant/cloudant/lib/eventrelay.js:78:21)\n    at Request.<anonymous> (/node_modules/request/request.js:1161:10)\n    at Request.emit (events.js:198:13)\n    at Request.self._source.emit (/node_modules/@cloudant/cloudant/lib/eventrelay.js:78:21)\n    at IncomingMessage.<anonymous> (/node_modules/request/request.js:1083:12)",
    "statusCode": 401
  }
}

The function code is as follows:

/**
 * Read a document in Cloudant database:
 * https://docs.cloudant.com/document.html#read
 **/

function main(message) {

    var cloudantOrError = getCloudantAccount(message);
    if (typeof cloudantOrError !== 'object') {
        return Promise.reject(cloudantOrError);
    }
    var cloudant = cloudantOrError;

    var dbName = message.dbname;
    var docId = message.docid || message.id;
    var params = {};

    if (!dbName) {
        return Promise.reject('dbname is required.');
    }
    if (!docId) {
        return Promise.reject('docid is required.');
    }
    var cloudantDb = cloudant.use(dbName);

    if (typeof message.params === 'object') {
        params = message.params;
    } else if (typeof message.params === 'string') {
        try {
            params = JSON.parse(message.params);
        } catch (e) {
            return Promise.reject('params field cannot be parsed. Ensure it is valid JSON.');
        }
    }

    return readDocument(cloudantDb, docId, params);
}

function readDocument(cloudantDb, docId, params) {
    return new Promise(function (resolve, reject) {
        cloudantDb.get(docId, params, function (error, response) {
            if (!error) {
                resolve(response);
            } else {
                console.error('error', error);
                reject(error);
            }
        });
    });
}

function getCloudantAccount(params) {

    var Cloudant = require('@cloudant/cloudant');
    var cloudant;

    if (!params.iamApiKey && params.url) {
        cloudant = Cloudant(params.url);
    } else {
        checkForBXCreds(params);

        if (!params.host) {
            return 'Cloudant account host is required.';
        }

        if (!params.iamApiKey) {
            if (!params.username || !params.password) {
                return 'You must specify parameter/s of iamApiKey or username/password';
            }
        }

        var protocol = params.protocol || 'https';
        if (params.iamApiKey) {
            var dbURL = `${protocol}://${params.host}`;
            if (params.port) {
                dbURL += ':' + params.port;
            }
            cloudant = new Cloudant({
                url: dbURL,
                plugins: {iamauth: {iamApiKey: params.iamApiKey, iamTokenUrl: params.iamUrl}}
            });
        } else {
            var url = `${protocol}://${params.username}:${params.password}@${params.host}`;
            if (params.port) {
                url += ':' + params.port;
            }
            cloudant = Cloudant(url);
        }
    }
    return cloudant;
}

function checkForBXCreds(params) {

    if (params.__bx_creds && (params.__bx_creds.cloudantnosqldb || params.__bx_creds.cloudantNoSQLDB)) {
        var cloudantCreds = params.__bx_creds.cloudantnosqldb || params.__bx_creds.cloudantNoSQLDB;

        if (!params.host) {
            params.host = cloudantCreds.host || (cloudantCreds.username + '.cloudant.com');
        }
        if (!params.iamApiKey && !cloudantCreds.apikey) {
            if (!params.username) {
                params.username = cloudantCreds.username;
            }
            if (!params.password) {
                params.password = cloudantCreds.password;
            }
        } else if (!params.iamApiKey) {
            params.iamApiKey = cloudantCreds.apikey;
        }
    }

}

Answer 1

Basically, copying and pasting those credentials led to it not working. Not sure why. To get a test invocation working I added url, docid, dbname, host, url and iamApiKey values to the parameters section of the function. That worked.