feat(router): provide access to all route params via router service. resolves #39

[meeroslav]

Problem:

Expose route params from the router component back to router service to have it available for all components.

The tricky part:

Since routes are not configured in central configuration (like in @angular/router) but rather loaded and parsed asynchronously from components, the routeParams will change until parsing has been fully finished.

Unrelated bug fixed separately (found in router component and service):

distinctUntilChanged does value referential comparison. It works nicely for strings, but for objects (such as Params) a custom comparison function must be provided e.g.:

const paramsCompare = (x,y) = x === y || JSON.stringify(x) === JSON.stringify(y)

[meeroslav]

@brandonroberts please verify if you agree with this functionality

[brandonroberts]

How does this handle naming collisions? I want to keep the route params relatively straightforward, and lean more on using the components to pass data around then trying to collect them all in the router service.

[meeroslav]

Currently, the child param has priority over the parent param:

// root params -> child params -> child params => pathRoutes
{ owner: 'Joe' } -> { car: 'Mustang' } -> { owner: 'Jane' } => { owner: 'Jane', car: 'Mustang' }

My rationale was to provide as many features as possible from the official @angular/router to motivate devs to migrate. Two of those features missing are:

• route guards (taken in separate issue)
• full path params

With the original router, we can access easily all path params (should a component need it). The current solution with angular-routing is to depend on parent components to pass it down to the child component. This leads to a rigid structure and complications when the component is moved around through DOM.

Back to name handling, we could return Params[] instead of Params. That would avoid naming collision and perhaps also provide more sense of hierarchy of params.

What do you think?

[brandonroberts]

We discussed tabling this feature for now, but will revisit