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Contributors

How to contribute

Prerequisites

Workflow

  • Have a look at the project board

  • Take an issue that’s in the ready section and has nobody assigned to it

  • Assign yourself

  • When you start working on it, move the issue to the “in progress” section

  • Work on a separate branch for the issue on your fork

  • When you’re ready, fire a pull request
  • in the comments of the pull request, write something akin to “this PR connect’s to #{the ID of the issue}”. That way the issue will be moved automatically to the review column.

  • When at least two people have reviewed and approved your PR, it can be merged in master.

  • You can also help out by reviewing the pull requests of other people
  • Please keep an eye on your pull request afterwards, the reviewers may have questions or comments about it, or ask you to tackle things in a different way, before they can approve it

  • Most discussions about the task or the pull request can happen through the github & project board comments.

  • If it’s more complex you can bring it up in one of these meetings.

  • After your Pull Request has been merged, drag the issue to the done column on the project board. (this can also be automated by adding “this merge closes #{the id of the issue}” in the merge comment.

  • If you've claimed an issue, but can't work on it for some reason, please remember to unassign yourself and put it back in the "ready" column so someone else can take over.

Guidelines

General

  • Before firing a PR, always ensure your code works on the server (disable javascript in your browser and see if it still works) as well as the client, and that it works with the AoT build (npm start) as well as the webpack build (npm run watch:dev)
  • Keep adaptability in mind. An institution installing DSpace will often want to modify a few things about the UI. The easier we can make that, the better. Therefore keep your components small (divide them in to sub-components), make sub-modules for coherent functionality, use SASS variables, etc.
  • We agreed to remove the concept of Communities from the UI. They should be called Collections as well. The decision to remove the concept of Communities from the UI was reversed in the meeting of April 13th

Code Style

  • Follow the official Angular style guide. It contains guidelines for naming files, directory structure, etc.
  • TSLint can help you with that. It will run automatically whenever the code is rebuilt (even during a watch task) or you can run it manually with npm run lint

Documentation

Testing

  • Write tests for your code. We use jasmine for unit testing and protractor for end-to-end.
  • Ensure your code doesn't break any existing tests.

Creating a new component

  • A new component should consist of at least 3 files, in the same folder
    • an HTML file, containing the template e.g. sidebar.component.html
    • an SCSS file, containing the style. Create this even if it's to remain empty. e.g. sidebar.component.scss
    • a TypeScript file, containing the component definition e.g. sidebar.component.ts
      • Its templateUrl attribute should contain a reference to the HTML file: e.g. templateUrl: './sidebar.component.html'
      • Its styleUrls attribute (this is an array) should contain a reference to the style file: e.g. styleUrls: ['./sidebar.component.css']
        • Note that styleUrls refers to a CSS file rather than an SCSS file.That's because the AoT build process doesn't yet support SCSS, and the SCSS files get converted to CSS ahead of time. More information in the comments on this PR.
      • it's selector attribute should start with ds- This ensures the component name contains a dash, and indicates it's a dspace component. e.g. selector: 'ds-sidebar'
      • Example:

        @Component({
            selector: 'ds-sidebar',
            styleUrls: ['./sidebar.component.css'],
            templateUrl: './sidebar.component.html'
        })
        export class SidebarComponent {
        }

(S)CSS

  • General
    • Avoid writing (S)CSS if you can. Instead use Bootstrap 4 CSS classes and components where possible. That way it will be much easier to keep the style consistent across many different contributors. 
    • If you want to use a bootstrap component, take a look at the ng-bootstrap docs first. Chances are they've already turned it into an angular component for you.
    • If you need to add margins, padding, change font-sizes or colors etc, make use of the bootstrap variables rather than entering numerical values. (e.g. write margin-bottom: $spacer-y; instead of margin-bottom: 15px; and color: $brand-primary; instead of color: #0275d8;)
    • If there's no other way but to add a numerical value or color code yourself, consider turning it in to a variable, so it can be reused by others. Also calculations that are used more than once can benefit from being stored as variables: e.g. $ds-table-margin-bottom: ($font-size-base * 2) - ($gutter-width / 2);
  • Component Styles

    • Angular 2 makes use of component styles. By default, these can't leak out and affect the style of other components. Not even child components
    • The style for a component should go in a file called name.component.scss, in the same directory as the component. e.g. for src/app/home/home.component.ts the component style file is src/app/home/home.component.scss.
    • Note that the styleUrls parameter of the component refers to a CSS file, not an SCSS file. That's because the AoT build process doesn't yet support SCSS, and the SCSS files get converted to CSS ahead of time. More information in the comments on this PR.

i18n

  • Don't hard code user-facing text in components. We're using ng2-translate for i18n. You use it by adding your key to resources/i18n/en.json, and then using that key in the component with the translate pipe. e.g.:
    • in en.json put:  "my-route.my-component.my-label-descriptor": "My User Facing Text";
    • in your component put: "<h1>{{ 'my-route.my-component.my-label-descriptor' | translate }}</h1>"
  • For more info see the ng2-translate docs

State changes

  • The state in this application is managed by ngrx
  • Using it properly requires some discipline from developers and reviewers.
  • If you're new to redux or ngrx, take a look at the resources on the technology page
  • Anything that's dynamic about the application is called a state change, and should be saved in the store. 
  • That means a boolean that saves if the navigation is open or closed, or a list of DSpace Objects from the backend, anything that can change as the application runs.
  • Every state change should be defined as an action. in a file called ${feature-name}-actions.ts. e.g. host-window.actions.ts
    An action definition consists of 
    • a type, in the format dspace/feature-name/ACTION-NAME, added to an ActionTypes object.
    • a class to represent the action, that takes the components of the payload as the parameters of its constructor
  • The effect of each action on the state should be defined in the reducer, in a file called ${feature-name}-reducer.ts. e.g. host-window.reducer.ts
  • If an action is be the source of another action, that relation is described in an effect.
    • e.g. submitting the login form dispatches a LOGIN_REQUEST action, with the user's credentials as its payload.
    • an AuthorizationEffect class listens for that action, and when it occurs it calls the rest api with those login credentials 
    • if the REST API answers positively, the AuthorizationEffect dispatches a new LOGIN_SUCESS action, with the token that was returned.
    • if the REST API returns an error, the AuthorizationEffect dispatches a new LOGIN_ERROR action, with the error message that was returned.
  • All reducers need to be added to a single reducer aggregator file per module before they can be used
  • The same needs to happen for effect files

DataServices and RemoteData objects

  • There is a DataService for each type of DSpaceObject.
  • These data services ensure resources get fetched from the rest api (the mock rest api at this point), and stored in the ngrx store
  • The find methods in the DataServices return RemoteData objects
  •  RemoteData objects contain the status of the request (loading/failed/succeeded) and the data (or error message), as observables.

This gist shows how you would use it in practice: 

  • In the component I specify that collectionData has the type RemoteData<Collection[]>

  • In the OnInit: this.collectionData = this.cds.findAll();

  • And then in the template, handle the different cases: dedicated messages for isLoading and hasFailed and the actual data for hasSucceeded 

    • of course in a more realistic scenario you might send the error to a notification service instead of handling it yourself

  • The async pipe allows you to use observables in the template as if they were plain objects.

  • Because of the observables, the template will update automatically if the data in the store gets updated







 

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