DEV Community: Brian Hanna

Import dependencies with Svelte and Rollup?

Brian Hanna — Thu, 12 Sep 2019 16:56:27 +0000

I'm trying out Svelte. I've followed the instructions on getting a starter project going. I've made some minor customizations, and added one library to help with making fetch requests (build-url).

Everything works great! I'm able to import build-url using this syntax in my Home.svelte file:

import buildUrl from '../node_modules/build-url';

However, I'm coming from Angular; I'm very, very used to omitting the path the node_modules from my code entirely; Angular just finds what it needs. My ideal end state would be the following:

import buildUrl from 'build-url';

Is there a Rollup configuration I can use to mimic this behavior? I'm not against using a path to the node_modules folder, but I can't help but feel like I'm doing it wrong. If I can't do it with Rollup, is it possible with another bundler like webpack or Parcel?

Connect to OracleDB from NodeJS?

Brian Hanna — Tue, 02 Jul 2019 01:30:09 +0000

I currently use Java ADF REST web services to access the data in a bunch of legacy Oracle databases. It's slow, static, one dimensional, and a huge pain point. I use NodeJS for the application servers, so I was hoping to implement some cleaner, more dynamic APIs to interface with the Oracle databases there.

However, I cannot, for the life of me, figure out how to connect to this database from NodeJS. I can get to the database via SQL Developer. I have a Data Source set up in the integrated WebLogic Server that ships with JDeveloper for the current web services that (seemingly) uses all the same information. I have all the information: the hostname, the username, the password, the port, and the SID. I've gotten the InstantClient installed and added to my PATH on my Mac. No configuration of this information seems to work properly in NodeJS. I'm using node-oracledb version 3.1.2 on NodeJS v10.15.3. My connection object looks like this:

{
  user: 'my_username',
  password: 'my_password',
  connectString: 'app.company.com:port:database_name'
}

The above configuration results in the error:

Error: ORA-12545: Connect failed because target host or object does not exist

So something is clearly wrong with my connection string. I have tried multiple permutations on the connectString as well, including:

app.company.com:port/database_name
- Error: ORA-12514: TNS:listener does not currently know of service requested in connect descriptor
jdbc:oracle:thin:@app.company.com:port:database_name
- Works with SQL Developer and WebLogic Server Data Source, but produces error ORA-12514 when used in NodeJS

I'm grasping at straws. All of the information I've found has been so dense as to be basically useless. I'm not a Java developer. I've never worked heavily with Oracle databases before. I'm sure there is some strange, arcane configuration thing that I'm missing, but I don't even know what questions to ask. Literally any additional information would be incredibly useful.

Oracle ADF REST Batch GET with query parameters?

Brian Hanna — Tue, 04 Jun 2019 18:31:51 +0000

I'm working with the Oracle ADF REST API for an app. I want to be able to batch some requests, but I'm not seeing a way to do so while also passing URL parameters. I asked this same question on SO back in September and have gotten nowhere since then: https://stackoverflow.com/questions/52320613/oracle-adf-bc-rest-api-batch-get-requests-with-url-parameters

AngularJS, IE11, and the Importance of Research

Brian Hanna — Tue, 04 Jun 2019 13:48:57 +0000

Yesterday, a bug was discovered in an app I maintain: a single text input was disabled in IE11 when it shouldn't be. I immediately jumped in, believing it to be a mis-fire with an ng-disabled statement. Nearly two hours later, zero progress was made. This seemed like such a simple fix on first blush!

It made no sense. The placeholder text was set as the value. The ng-model binding didn't update in the controller on text entry. The submit action did nothing when I hit enter, but worked on clicking the submit button for the form. The input fired a test function from an ng-click, but didn't from ng-focus or ng-blur. I decided to cut my losses and leave it for the morning.

Today, after (not really) sleeping on it, I took another look. I broadened my search terms, hoping to get hint of a solution. A number of searches later, the secret words ended up being: angularjs strange form behavior ie11.

Embarassingly, that (in hindsight) obvious phrase led me to the official AngularJS Developer Guide, which describes exactly what I was seeing in my app:

Using the disabled attribute on an element that has descendant form controls can result in unexpected behavior in Internet Explorer 11. For example, the value of descendant input elements with ng-model will not reflect the model (or changes to the model), and the value of the placeholder attribute will be inserted as the input's value. Descendant select elements will also be inoperable, as if they had the disabled attribute applied to them, which may not be the intended effect. To work around this unexpected behavior, 1) avoid using the identifier disabled for custom attribute directives that are on elements with descendant form controls, and 2) avoid using disabled as an identifier for an attribute passed to a custom directive that has descendant form controls.

—AngularJS: Developer Guide: Internet Explorer Compatibility

Upon examining the parent components, I found the source of my pain. Somebody on my team (of one) had used disabled as an identifier for a binding on the parent component, which falls into the category of custom directives that have descendant form controls! By simply renaming the binding to isDisabled and using the attribute is-disabled, the entire issue disappeared.

Let my over-confidence be a warning to others: Read. The. F***ing. Manual.