Tips - Do you have a pleasant development workflow?
2/11/2018 4:10 AM by
UPDATE: This has been properly fixed since Angular 4. So now, this rule is irrelevant because Angular CLI provides a pleasant development workflow. Using ng serve, TypeScript transpilation occurs automatically and quickly (almost instantly).
When dealing with client-side development – especially when transpiling TypeScript – it is common to have to wait for several seconds between writing code, and seeing the results.
This adds up quickly – if you have to wait for 5 seconds every 3 minutes, you've spent 13 minutes of your day just waiting. This is a conservative estimate - we change code much more frequently than every 3 minutes!
A naïve development experience is as follows:
- Make a code change using a misconfigured IDE
- See errors everywhere as you type (even though the code is perfectly fine)
- Inaccurate IntelliSense information
- Compile the code
- Run a gulp task to copy files around appropriately
- This often takes a few seconds to run, especially if it “cleans” the folder beforehand
- Refresh the page
- Depending on the setup, this may take anywhere from milliseconds to seconds
- Click around until the app is in the right state to test the functionality
- If there is too much built-up state, and no routes set up, this chews up time
- Bad example - Many hours each week are wasted just waiting for the code you wrote to run
A more ideal workflow is:
- Make the change using a properly configured IDE
- One that only shows errors when they’re appropriate
- Intellisense shows everything available, and nothing more
- Refresh the page (maybe)
- With well set up watches for compilation and appropriate use of BrowserLink or LiveReload, this is very fast
- With proper bundling, the initial page load is also fast in development environments.
- Already be at the component required, ready to check it works
- Good example - No time is wasted doing repetitive and slow tasks
Remember: Spending 4 hours setting up a good dev experience will pay for itself within the week, and make your work like much happier.
Guidelines to follow
- Ensure that only the files that are changed need to be compiled – TypeScript handles this quite well with --watch
- Avoid the use of task runners (eg. gulp) as part of your development flow. A few watches should be all you need. Save the task runners for release builds
- Consider separate index pages for production and development, using the dev libraries for development, and minified/bundled ones for production
- Use module loaders (eg. SystemJS) to manage dependencies and their associated bundlers/builders for releases
- Load 3rd party modules (eg. Angular2 and Rx) as a bundle, not as their individual files – speed up development first-page load
- Think about your routing – a refresh should almost always return the page to the exact same state or at the very least, the same screen
- Most importantly, be unsatisfied - if things are slow, fix it. If you constantly have to manually close IISExpress to run your app, find out why and fix it! You will save everyone time in the long run
Do you feel this rule needs an update?