tutorial: using django as endpoint

[amitu]

Status: In Done

Previous Task Discussion
TODO Service
TODO APP
FTD PR

Tasks

• Request Data Processor
• TODO mock API(add todo, list todo, update todo)
• Add todo, list todo, etc, ftd files
• Handle Submit forms Handle errors, Handle redirect, handle redirect
• package has to use the package urls: end-point support for dependency #590

30 September

• https://github.com/FifthTry/kameri

---

Key Blockers

• multi mount-point: https://github.com/ftd-lang/fpm/discussions/599
• mount-point: mount-point for clean URLs #550
• endpoint: `end-point` support #462
• dynamic urls in sitemap #569
• dynamic sitemap #311
• sitemap should have custom url support #465
• https://github.com/ftd-lang/fpm/discussions/551

Fetching Request Data

-- rd rd:
$processor$: request-data

Fetching Data from Django

To fetch data we use the http processor. The key missing feature is how do know the endpoint URL? Do we mention the endpoint URL everywhere where http processor is used?

-- data r:
$processor$: http
url: https://abrak-fpm-app.herokuapps.com/api/get-movie/
movie-id: $rd.id

Instead we should be able to write:

-- data r:
$processor$: http
$endpoint$: fifthtry.github.io/movie-db
url: /api/get-movie/
movie-id: $rd.id

If in our FPM.ftd we have:

-- fpm.package: abrark.com
-- fpm.dependency: fifthtry.github.io/movie-db
endpoint: https://abrak-fpm-app.herokuapps.com/

NOTE: We will not include endpoint stuff in this tutorial. We will ask people to deploy django separately on heroku. We will even let them use our deployed django.

Lets show some minimal django view, and the JSON that is returned.

<django code> <todo>

{ "todo": true }

Handling Form

A form when submitted must either return some data, error, or a redirect.

Data Handling

Data handling is rare, it is possible but we do not encourage it. We encourage redirect on success.

todo: show a form

show django code

the repose will update a ftd variable, show the variable definition

Show UI screenshots.

Error Handling

Django will return form error. We handle errors exactly the same way as data, django has to return the variable names and values.

{
    "abrark.com/login#username-error": "Username is already taken",
    "abrark.com/login#password-error": "Minimum length of password is 8"
}

Show a ftd file containing error variables:

-- optional string username-error:
-- optional string password-error:

And where the form is displayed, show these error messages if they are not null.

Redirect Handling

Django has to simply return:

{
    "redirect": "/"
}

And ftd.js takes care of redirection.

TODOs

Ensure Cookies Can Be Passed To http processor

Must be opt-in.

-- data r:
$processor$: http
$endpoint$: fifthtry.github.io/movie-db
$forward-cookie$: sid
url: /api/get-movie/
movie-id: $rd.id

If cookie is present it will be sent up stream. If upstream modifies the cookie, it should be sent as part of response too. Every time http processor is called, cookie from response should be stored, and sent to browser at the end of http request.

Only cookie matching $forward-cookie$ will be sent/updated. We will also support $forward-all-cookies$, where all cookies would be sent/updated.

App

In the tutorial we will create a simple todo app. The entire logic would be in todo.ftd.

Django will have APIs:

• /api/todos/
• /api/create-todo/
• /api/mark-todo-done/

We will use $forward-all-cookies$ feature for this. We will create "tracker" cookie from django, a cookie that uniquely identifies the devices. Only todos created on this device would be visible on this device.

Audience

We will show the API docs of the app first. The three apis listed above. And basically emphasise that we have done it in django, but it can be node, ruby, whatever.

Then we will focus of tutorial is building ftd-django interaction.