Services¶

Services are long lived pieces of code that provide a feature. They may be imported by components (with useService) or by other services. Also, they can declare a set of dependencies. In that sense, services are basically a DI dependency injection system. For example, the notification service provides a way to display a notification, or the rpc service is the proper way to perform a request to the Flectra server.

The following example registers a simple service that displays a notification every 5 seconds:

import { registry } from "@web/core/registry";

const myService = {
    dependencies: ["notification"],
    start(env, { notification }) {
        let counter = 1;
        setInterval(() => {
            notification.add(`Tick Tock ${counter++}`);
        }, 5000);
    }
};

registry.category("services").add("myService", myService);

At startup, the web client starts all services present in the services registry. Note that the name used in the registry is the name of the service.

Note

Most code that is not a component should be packaged in a service, in particular if it performs some side effect. This is very useful for testing purposes: tests can choose which services are active, so there are less chance for unwanted side effects interfering with the code being tested.

Defining a service¶

A service needs to implement the following interface:

dependencies¶: Optional list of strings. It is the list of all dependencies (other services) that this service needs

start(env, deps)¶

Arguments

env (Environment()) – the application environment
deps (Object()) – all requested dependencies

Returns

value of service or Promise<value of service>

This is the main definition for the service. It can return either a value or a promise. In that case, the service loader simply waits for the promise to resolve to a value, which is then the value of the service.

Some services do not export any value. They may just do their work without a need to be directly called by other code. In that case, their value will be set to null in env.services.

async¶

Optional value. If given, it should be true or a list of strings.

Some services need to provide an asynchronous API. For example, the rpc service is an asynchronous function, or the orm service provides a set of functions to call the Flectra server.

In that case, it is possible for components that use a service to be destroyed before the end of an asynchronous function call. Most of the time, the asynchronous function call needs to be ignored. Doing otherwise is potentially very risky, because the underlying component is no longer active. The async flag is a way to do just that: it signals to the service creator that all asynchronous calls coming from components should be left pending if the component is destroyed.

Using a service¶

A service that depends on other services and has properly declared its dependencies simply receives a reference to the corresponding services in the second argument of the start method.

The useService hook is the proper way to use a service in a component. It simply returns a reference to the service value, that can then be used by the component later. For example:

import { useService } from "@web/core/utils/hooks";

class MyComponent extends Component {
  setup() {
    const rpc = useService("rpc");

    onWillStart(async () => {
      this.someValue = await rpc(...);
    });
  }
}

Reference List¶

Technical Name	Short Description
cookie	read or modify cookies
effect	display graphical effects
http	perform low level http calls
notification	display notifications
router	manage the browser url
rpc	send requests to the server
scroller	handle clicks on anchors elements
title	read or modify the window title
user	provides some information related to the current user

Overview¶

Technical name: cookie
Dependencies: none

Provides a way to manipulate cookies. For example:

cookieService.setCookie("hello", "flectra");

API¶

current¶: Object representing each cookie and its value if any (or empty string)

setCookie(name[, value, ttl])¶

Arguments

name (string()) – the name of the cookie that should be set
value (any()) – optional. If given, the cookie will be set to that value
ttl (number()) – optional. the time in seconds before the cookie will be deleted (default=1 year)

Sets the cookie name to the value value with a max age of ttl

deleteCookie(name)¶

Arguments

name (string()) – name of the cookie

Deletes the cookie name.

Effect service¶

Overview¶

Technical name: effect
Dependencies: None

Effects are graphical elements that can be temporarily displayed on top of the page, usually to provide feedback to the user that something interesting happened.

A good example would be the rainbow man:

Here’s how this can be displayed:

const effectService = useService("effect");
effectService.add({
  type: "rainbow_man", // can be omitted, default type is already "rainbow_man"
  message: "Boom! Team record for the past 30 days.",
});

Warning

The hook useEffect is not related to the effect service.

API¶

effectService.add(options)¶

Arguments

options (object()) – the options for the effect. They will get passed along to the underlying effect component.

Display an effect.

The options are defined by:

interface EffectOptions {
  // The name of the desired effect
  type?: string;
  [paramName: string]: any;
}

Available effects¶

Currently, the only effect is the rainbow man.

RainbowMan¶

effectService.add({ type: "rainbow_man" });

Name	Type	Description
`params.Component`	`owl.Component?`	Component class to instantiate inside the RainbowMan (will replace the message).
`params.props`	`object?={}`	If params.Component is given, its props can be passed with this argument.
`params.message`	`string?="Well Done!"`	Message is the notice the rainbowman holds. If effects are disabled for the user, the rainbowman won’t appear and a simple notification will get displayed as a fallback. If effects are enabled and params.Component is given, params.message is not used. The message is a simple string or a string representing html (prefer using params.Component if you want interactions in the DOM).
`params.messageIsHtml`	`boolean?=false`	Set to true if the message represents html, s.t. it will be correctly inserted into the DOM.
`params.img_url`	`string?=/web/static/img/smile.svg`	The url of the image to display inside the rainbow.
`params.fadeout`	`("slow"\|"medium"\|"fast"\|"no")?="medium"`	Delay for rainbowman to disappear. `"fast"` will make rainbowman dissapear quickly. `"medium"` and `"slow"` will wait little longer before disappearing (can be used when `params.message` is longer). `"no"` will keep rainbowman on screen until user clicks anywhere outside rainbowman.

How to add an effect¶

The effects are stored in a registry called effects. You can add new effects by providing a name and a function.

const effectRegistry = registry.category("effects");
effectRegistry.add("rainbow_man", rainbowManEffectFunction);

The function must follow this API:

<newEffectFunction>(env, params)¶

Arguments

env (Env()) – the environment received by the service
params (object()) – the params received from the add function on the service.

Returns

({Component, props} | void) A component and its props or nothing.

This function must create a component and return it. This component is mounted inside the effect component container.

Example¶

Let’s say we want to add an effect that add a sepia look at the page.

/** @flectra-module **/

import { registry } from "@web/core/registry";
const { Component, tags } = owl;

class SepiaEffect extends Component {}
SepiaEffect.template = tags.xml`
    <div style="
        position: absolute;
        left: 0;
        top: 0;
        width: 100%;
        height: 100%;
        pointer-events: none;
        background: rgba(124,87,0, 0.4);
    "></div>
`;

export function sepiaEffectProvider(env, params = {}) {
    return {
        Component: SepiaEffect,
    };
}

const effectRegistry = registry.category("effects");
effectRegistry.add("sepia", sepiaEffectProvider);

And then, call it somewhere you want and you will see the result. Here, it is called in webclient.js to make it visible everywhere for the example.

const effectService = useService("effect");
effectService.add({ type: "sepia" });

Http Service¶

Overview¶

Technical name: http
Dependencies: None

While most interactions between the client and the server in flectra are RPCs (XMLHTTPRequest), lower level control on requests may sometimes be required.

This service provides a way to send get and post http requests.

API¶

async get(route[, readMethod = "json"])¶

Arguments

route (string()) – the url to send the request to
readMethod (string()) – the response content type. Can be “text”, “json”, “formData”, “blob”, “arrayBuffer”.

Returns

the result of the request with the format defined by the readMethod argument.

Sends a get request.

async post(route[, params = {}, readMethod = "json"])¶

Arguments

route (string()) – the url to send the request to
params (object()) – key value data to be set in the form data part of the request
readMethod (string()) – the response content type. Can be “text”, “json”, “formData”, “blob”, “arrayBuffer”.

Returns

the result of the request with the format defined by the readMethod argument.

Sends a post request.

Example¶

const httpService = useService("http");
const data = await httpService.get("https://something.com/posts/1");
// ...
await httpService.post("https://something.com/posts/1", { title: "new title", content: "new content" });

Notification service¶

Overview¶

Technical name: notification
Dependencies: None

The notification service allows to display notifications on the screen.

const notificationService = useService("notification");
notificationService.add("I'm a very simple notification");

API¶

add(message[, options])¶

Arguments

message (string()) – the notification message to display
options (object()) – the options of the notification

Returns

a function to close the notification

Shows a notification.

The options are defined by:

Name	Type	Description
`title`	string	Add a title to the notification
`type`	`warning` \| `danger` \| `success` \| `info`	Changes the background color according to the type
`sticky`	boolean	Whether or not the notification should stay until dismissed
`className`	string	additional css class that will be added to the notification
`onClose`	function	callback to be executed when the notification closes
`buttons`	button[] (see below)	list of button to display in the notification

The buttons are defined by:

Name	Type	Description
`name`	string	The button text
`onClick`	function	callback to execute when the button is clicked
`primary`	boolean	whether the button should be styled as a primary button

Examples¶

A notification for when a sale deal is made with a button to go some kind of commission page.

// in setup
this.notificationService = useService("notification");
this.actionService = useService("action");

// later
this.notificationService.add("You closed a deal!", {
  title: "Congrats",
  type: "success",
  buttons: [
      {
          name: "See your Commission",
          onClick: () => {
              this.actionService.doAction("commission_action");
          },
      },
  ],
});

A notification that closes after a second:

const notificationService = useService("notification");
const close = notificationService.add("I will be quickly closed");
setTimeout(close, 1000);

Router Service¶

Overview¶

Technical name: router
Dependencies: none

The router service provides three features:

information about the current route
a way for the application to update the url, depending on its state
listens to every hash change, and notifies the rest of the application

API¶

current

The current route can be accessed with the current key. It is an object with the following information:

pathname (string): the path for the current location (most likely /web )
search (object): a dictionary mapping each search keyword (the querystring) from the url to its value. An empty string is the value if no value was explicitely given
hash (object): same as above, but for values described in the hash.

For example:

// url = /web?debug=assets#action=123&owl&menu_id=174
const { pathname, search, hash } = env.services.router.current;
console.log(pathname); //   /web
console.log(search); //   { debug="assets" }
console.log(hash); //   { action:123, owl: "", menu_id: 174 }

Updating the URL is done with the pushState method:

pushState(hash: object[, replace?: boolean])¶

Arguments

hash (Object()) – object containing a mapping from some keys to some values
replace (boolean()) – if true, the url will be replaced, otherwise only key/value pairs from the hash will be updated.

Updates the URL with each key/value pair from the hash object. If a value is set to an empty string, the key is added to the url without any corresponding value.

If true, the replace argument tells the router that the url hash should be completely replaced (so values not present in the hash object will be removed).

This method call does not reload the page. It also does not trigger a hashchange event, nor a ROUTE_CHANGE in the main bus. This is because this method is intended to only updates the url. The code calling this method has the responsibility to make sure that the screen is updated as well.

For example:

// url = /web#action_id=123
routerService.pushState({ menu_id: 321 });
// url is now /web#action_id=123&menu_id=321
routerService.pushState({ yipyip: "" }, replace: true);
// url is now /web#yipyip

Finally, the redirect method will redirect the browser to a specified url:

redirect(url[, wait])¶

Arguments

url (string()) – a valid url
wait (boolean()) – if true, wait for the server to be ready, and redirect after

Redirect the browser to url. This method reloads the page. The wait argument is rarely used: it is useful in some cases where we know that the server will be unavailable for a short duration, typically just after an addon update or install operation.

Note

The router service emits a ROUTE_CHANGE event on the main bus whenever the current route has changed.

RPC service¶

Overview¶

Technical name: rpc
Dependencies: none

The rpc service provides a single asynchronous function to send requests to the server. Calling a controller is very simple: the route should be the first argument and optionally, a params object can be given as a second argument.

// in setup
this.rpc = useService("rpc");

// somewhere else, in an async function:
const result = await this.rpc("/my/route", { some: "value" });

Note

Note that the rpc service is considered a low-level service. It should only be used to interact with Flectra controllers. To work with models (which is by far the most important usecase), one should use the orm service instead.

API¶

rpc(route, params, settings)¶

Arguments

route (string()) – route targeted by the request
params (Object()) – parameters sent to the server
(optional) (Object settings()) – request settings (see below)

The settings object can contain:

xhr, which should be a XMLHTTPRequest object. In that case, the rpc method will simply use it instead of creating a new one. This is useful when one accesses advanced features of the XMLHTTPRequest API.
silent (boolean) If set to true, the web client will not provide a feedback that there is a pending rpc.

The rpc service communicates with the server by using a XMLHTTPRequest object, configured to work with the application/json content type. So clearly the content of the request should be JSON serializable. Each request done by this service uses the POST http method.

Server errors actually return the response with an http code 200. But the rpc service will treat them as error.

Error Handling¶

An rpc can fail for two main reasons:

either the flectra server returns an error (so, we call this a server error). In that case the http request will return with an http code 200 BUT with a response object containing an error key.
or there is some other kind of network error

When a rpc fails, then:

the promise representing the rpc is rejected, so the calling code will crash, unless it handles the situation
an event RPC_ERROR is triggered on the main application bus. The event payload contains a description of the cause of the error:

If it is a server error (the server code threw an exception). In that case the event payload will be an object with the following keys:
- type = 'server'
- message(string)
- code(number)
- name(string) (optional, used by the error service to look for an appropriate dialog to use when handling the error)
- subType(string) (optional, often used to determine the dialog title)
- data(object) (optional object that can contain various keys among which debug : the main debug information, with the call stack)
If it is a network error, then the error description is simply an object {type: 'network'}. When a network error occurs, a notification is displayed and the server is regularly contacted until it responds. The notification is closed as soon as the server responds.

Scroller service¶

Overview¶

Technical name: scroller
Dependencies: none

Whenever the user clicks on an anchor in the web client, this service automatically scrolls to the target (if appropriate).

The service adds an event listener to get click’s on the document. The service checks if the selector contained in its href attribute is valid to distinguish anchors and Flectra actions (e.g. <a href="#target_element"></a>). It does nothing if it is not the case.

An event SCROLLER:ANCHOR_LINK_CLICKED is triggered on the main application bus if the click seems to be targeted at an element. The event contains a custom event containing the element matching and its id as a reference. It may allow other parts to handle a behavior relative to anchors themselves. The original event is also given as it might need to be prevented. If the event is not prevented, then the user interface will scroll to the target element.

API¶

The following values are contained in the anchor-link-clicked custom event explained above.

Name	Type	Description
`element`	`HTMLElement \| null`	The anchor element targeted by the href
`id`	`string`	The id contained in the href
`originalEv`	`Event`	The original click event

Note

The scroller service emits a SCROLLER:ANCHOR_LINK_CLICKED event on the main bus. To avoid the default scroll behavior of the scroller service, you must use preventDefault() on the event given to the listener so that you can implement your own behavior correctly from the listener.

Title Service¶

Overview¶

Technical name: title
Dependencies: none

The title service offers a simple API that allows to read/modify the document title. For example, if the current document title is “Flectra”, we can change it to “Flectra 15 - Apple” by using the following command:

// in some component setup method
const titleService = useService("title");

titleService.setParts({ flectra: "Flectra 15", fruit: "Apple" });

API¶

The title service manipulates the following interface:

interface Parts {
    [key: string]: string | null;
}

Each key represents the identity of a part of the title, and each value is the string that is displayed, or null if it has been removed.

Its API is:

current: This is a string representing the current title. It is structured in the following way: value_1 - ... - value_n where each value_i is a (non null) value found in the Parts object (returned by the getParts function)

getParts()¶

Returns: Parts the current Parts object maintained by the title service

setParts(parts)¶

Arguments

parts (Parts()) – object representing the required change

The setParts method allows to add/replace/delete several parts of the title. Delete a part (a value) is done by setting the associated key value to null.

Note that one can only modify a single part without affecting the other parts. For example, if the title is composed of the following parts:

{ flectra: "Flectra", action: "Import" }

with current value being Flectra - Import , then

setParts({
  action: null,
});

will change the title to Flectra.

User service¶

Overview¶

Technical name: user
Dependencies: rpc

The user service provides a bunch of data and a few helper functions concerning the connected user.

API¶

Name	Type	Description
`context`	`Object`	The user context
`db`	`Object`	Info about the database
`home_action_id`	`(number \| false)`	Id of the action used as home for the user
`isAdmin`	`boolean`	Whether the user is an admin (group `base.group_erp_manager` or superuser)
`isSystem`	`boolean`	Whether the user is part of the system group (`base.group_system`)
`lang`	`string`	language used
`name`	`string`	Name of the user
`partnerId`	`number`	Id of the partner instance of the user
`tz`	`string`	The timezone of the user
`userId`	`number`	Id of the user
`userName`	`string`	Alternative nick name of the user

updateContext(update)¶

Arguments

update (object()) – the object to update the context with

update the user context with the given object.

userService.updateContext({ isFriend: true })

removeFromContext(key)¶

Arguments

key (string()) – the key of the targeted attribute

remove the value with the given key from the user context

userService.removeFromContext("isFriend")

hasGroup(group)¶

Arguments

group (string()) – the xml_id of the group to look for

Returns

Promise<boolean> is the user in the group

check if the user is part of a group

const isInSalesGroup = await userService.hasGroup("sale.group_sales")

Edit on GitHub

Services¶

Defining a service¶

Using a service¶

Reference List¶

Cookie service¶

Overview¶

API¶

Effect service¶

Overview¶

API¶

Available effects¶

RainbowMan¶

How to add an effect¶

Example¶

Http Service¶

Overview¶

API¶

Example¶

Notification service¶

Overview¶

API¶

Examples¶

Router Service¶

Overview¶

API¶

RPC service¶

Overview¶

API¶

Error Handling¶

Scroller service¶

Overview¶

API¶

Title Service¶

Overview¶

API¶

User service¶

Overview¶

API¶