refactor project-config and fix #823

[raupach]

In my opinion, the configuration and the calculated values should be clearly separated.

I have done the following:

• project.config.ts is now an abstract base class of seed.config.ts
• all configuration-values moved to project.config.ts
• seed.config.ts holds the calculated values.
• I split up some values. Example: CSS_DEST = ${this.APP_DEST}/${this.CSS_DEST_DIR};`

[TheDonDope]

Hi @raupach,
thank you for the PR. I can see your motivation behind the separation of the calculated values, however reversing the class hierarchy would break the general semantic division we have for the tooling (say all seed provided tasks residing in tools/tasks/seed, and project specific ones in tools/tasks/project; same for utils etc.). Therefore i would rather not stray away from this schema for the config part.

[lifaon74]

I join @raupach

This is painfull than attribute values are computed at the instanciation of seed.config.ts. This implies we need to copy ALL the attributes from seed.config.ts to project.config.ts before changind their values... From my point of view, all computed values should be placed into methods.

[mgechev]

We're discussing the best way to implement such computed properties in this PR #968. We'd love to hear another opinion.

[raupach]

Hi @TheDonDope,

but there, nothing has changed - except that project.config.ts holds ALL the configuration-values.
Lets say, project.config.ts holds all the default values and the individual project can now change these values.

The calculation of further values takes place AFTER "reading" project.config.ts at seed.config.ts.
And - this is important - seed.config.ts did not hold additional constants. For Example:

before:
seed.config.ts: CSS_SRC = ${this.APP_SRC}/css;

after:
project.config.ts: CSS_DIR = 'css';
CSS_SRC = ${this.APP_SRC}/${this.CSS_DIR};

Thes application is now highly configurable and with a little more calculation even empty values are possible.

[mgechev]

There's merge conflict. Lets discuss the best way to solve #823 here #968.