How to grab value from promise in Nodejs

Question

Hi I am writing a nodejs code in Azure functions to capture the username saved in Azure key vault. Here is the code I have written

module.exports = async function (context, req) {
    var msRestAzure = require('ms-rest-azure');
    var KeyVault = require('azure-keyvault');

    function getKeyVaultCredentials() {
        return msRestAzure.loginWithAppServiceMSI({
        resource: 'https://vault.azure.net/'
     });
    }

    function getKeyVaultSecret(credentials) {
        let keyVaultClient = new KeyVault.KeyVaultClient(credentials);
        return keyVaultClient.getSecret('https://myDNS.vault.azure.net/', 'username', '');
    }


const username = getKeyVaultCredentials()
 .then(getKeyVaultSecret)
 .then(function (secret){
 context.log(`Your secret value is: ${secret.value}.`);
    return secret.value;})
 .catch(function (err) {throw (err);});

context.log(username) 
    context.res = {
        body: username 
    };
}

I want to capture the username but it is giving me output as

promise {pending}

How to wait for the function to end so that I can extract the username.

I am very new nodejs, please let me know what wrong I am doing and what should be the exact solution.

Thanks

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise describes promises very well. It will help if you read it. — Hogan, Jun 22 '20 at 19:39

score 1 · Accepted Answer · answered Jun 23 '20 at 06:49

Actually you have already used then to get the secret value. The value will be returned if there is no issues with the dependencies and configurations.

getKeyVaultCredentials()
 .then(getKeyVaultSecret)
 .then(function (secret){
 context.log(`Your secret value is: ${secret.value}.`);
    return secret.value;})
 .catch(function (err) {throw (err);});

But you will encounter some issues when using this sdk and here is the github issue for your reference.

It is recommended that you use the new Azure Key Vault SDK instead. It is more convenient to use. Here are the detailed steps to use MSI and Key vault in Azure function.

How to grab value from promise in Nodejs

1 Answers1