26 KiB
Server-side hooks
These hooks are called on server-side.
loadSettings
Called from: src/node/server.js
Things in context:
- settings - the settings object
Use this hook to receive the global settings in your plugin.
shutdown
Called from: src/node/server.js
Things in context: None
This hook runs before shutdown. Use it to stop timers, close sockets and files, flush buffers, etc. The database is not available while this hook is running. The shutdown function must not block for long because there is a short timeout before the process is forcibly terminated.
The shutdown function must return a Promise, which must resolve to undefined
.
Returning callback(value)
will return a Promise that is resolved to value
.
Example:
// using an async function
exports.shutdown = async (hookName, context) => {
await flushBuffers();
};
pluginUninstall
Called from: src/static/js/pluginfw/installer.js
Things in context:
- plugin_name - self-explanatory
If this hook returns an error, the callback to the uninstall function gets an error as well. This mostly seems useful for handling additional features added in based on the installation of other plugins, which is pretty cool!
pluginInstall
Called from: src/static/js/pluginfw/installer.js
Things in context:
- plugin_name - self-explanatory
If this hook returns an error, the callback to the install function gets an error, too. This seems useful for adding in features when a particular plugin is installed.
init_<plugin name>
Called from: src/static/js/pluginfw/plugins.js
Things in context: None
This function is called after a specific plugin is initialized. This would probably be more useful than the previous two functions if you only wanted to add in features to one specific plugin.
expressConfigure
Called from: src/node/hooks/express.js
Things in context:
- app - the main application object
This is a helpful hook for changing the behavior and configuration of the application. It's called right after the application gets configured.
expressCreateServer
Called from: src/node/hooks/express.js
Things in context:
- app - the main express application object (helpful for adding new paths and such)
- server - the http server object
This hook gets called after the application object has been created, but before it starts listening. This is similar to the expressConfigure hook, but it's not guaranteed that the application object will have all relevant configuration variables.
expressCloseServer
Called from: src/node/hooks/express.js
Things in context: Nothing
This hook is called when the HTTP server is closing, which happens during
shutdown (see the shutdown hook) and when the server restarts (e.g., when a
plugin is installed via the /admin/plugins
page). The HTTP server may or may
not already be closed when this hook executes.
Example:
exports.expressCloseServer = async () => {
await doSomeCleanup();
};
eejsBlock_<name>
Called from: src/node/eejs/index.js
Things in context:
- content - the content of the block
This hook gets called upon the rendering of an ejs template block. For any specific kind of block, you can change how that block gets rendered by modifying the content object passed in.
Available blocks in pad.html
are:
htmlHead
- after<html>
and immediately before the title tagstyles
- the style<link>
sbody
- the contents of the body tageditbarMenuLeft
- the left tool bar (consider using the toolbar controller instead of manually adding html here)editbarMenuRight
- right tool barafterEditbar
- allows you to add stuff immediately after the toolbaruserlist
- the contents of the userlist dropdownloading
- the initial loading messagemySettings
- the left column of the settings dropdown ("My view"); intended for adding checkboxes onlymySettings.dropdowns
- add your dropdown settings hereglobalSettings
- the right column of the settings dropdown ("Global view")importColumn
- import formexportColumn
- export formmodals
- Contains all connectivity messagesembedPopup
- the embed dropdownscripts
- Add your script tags here, if you really have to (consider use client-side hooks instead)
timeslider.html
blocks:
timesliderStyles
timesliderScripts
timesliderBody
timesliderTop
timesliderEditbarRight
modals
index.html
blocks:
indexCustomStyles
- contains theindex.css
<link>
tag, allows you to add your own or to customize the one provided by the active skinindexWrapper
- contains the form for creating new padsindexCustomScripts
- contains theindex.js
<script>
tag, allows you to add your own or to customize the one provided by the active skin
padInitToolbar
Called from: src/node/hooks/express/specialpages.js
Things in context:
- toolbar - the toolbar controller that will render the toolbar eventually
Here you can add custom toolbar items that will be available in the toolbar config in settings.json
. For more about the toolbar controller see the API section.
Usage examples:
onAccessCheck
Called from: src/node/db/SecurityManager.js
Things in context:
- padID - the pad the user wants to access
- token - the token of the author
- sessionCookie - the session the use has
This hook gets called when the access to the concrete pad is being checked. Return false
to deny access.
padCreate
Called from: src/node/db/Pad.js
Things in context:
- pad - the pad instance
- author - the id of the author who created the pad
This hook gets called when a new pad was created.
padLoad
Called from: src/node/db/Pad.js
Things in context:
- pad - the pad instance
This hook gets called when a pad was loaded. If a new pad was created and loaded this event will be emitted too.
padUpdate
Called from: src/node/db/Pad.js
Things in context:
- pad - the pad instance
- author - the id of the author who updated the pad
- revs - the index of the new revision
- changeset - the changeset of this revision (see Changeset Library)
This hook gets called when an existing pad was updated.
padCopy
Called from: src/node/db/Pad.js
Things in context:
- originalPad - the source pad instance
- destinationID - the id of the pad copied from originalPad
This hook gets called when an existing pad was copied.
Usage examples:
padRemove
Called from: src/node/db/Pad.js
Things in context:
- padID
This hook gets called when an existing pad was removed/deleted.
Usage examples:
socketio
Called from: src/node/hooks/express/socketio.js
Things in context:
- app - the application object
- io - the socketio object
- server - the http server object
I have no idea what this is useful for, someone else will have to add this description.
preAuthorize
Called from: src/node/hooks/express/webaccess.js
Things in context:
- req - the request object
- res - the response object
- next - bypass callback. If this is called instead of the normal callback then all remaining access checks are skipped.
This hook is called for each HTTP request before any authentication checks are performed. Example uses:
- Always grant access to static content.
- Process an OAuth callback.
- Drop requests from IP addresses that have failed N authentication checks within the past X minutes.
A preAuthorize function is always called for each request unless a preAuthorize function from another plugin (if any) has already explicitly granted or denied the request.
You can pass the following values to the provided callback:
[]
defers the access decision to the normal authentication and authorization checks (or to a preAuthorize function from another plugin, if one exists).[true]
immediately grants access to the requested resource, unless the request is for an/admin
page in which case it is treated the same as[]
. (This prevents buggy plugins from accidentally granting admin access to the general public.)[false]
immediately denies the request. The preAuthnFailure hook will be called to handle the failure.
Example:
exports.preAuthorize = (hookName, context, cb) => {
if (ipAddressIsFirewalled(context.req)) return cb([false]);
if (requestIsForStaticContent(context.req)) return cb([true]);
if (requestIsForOAuthCallback(context.req)) return cb([true]);
return cb([]);
};
authorize
Called from: src/node/hooks/express/webaccess.js
Things in context:
- req - the request object
- res - the response object
- next - ?
- resource - the path being accessed
This hook is called to handle authorization. It is especially useful for controlling access to specific paths.
A plugin's authorize function is only called if all of the following are true:
- The request is not for static content or an API endpoint. (Requests for static content and API endpoints are always authorized, even if unauthenticated.)
- The
requireAuthentication
andrequireAuthorization
settings are both true. - The user has already successfully authenticated.
- The user is not an admin (admin users are always authorized).
- The path being accessed is not an
/admin
path (/admin
paths can only be accessed by admin users, and admin users are always authorized). - An authorize function from a different plugin has not already caused authorization to pass or fail.
Note that the authorize hook cannot grant access to /admin
pages. If admin
access is desired, the is_admin
user setting must be set to true. This can be
set in the settings file or by the authenticate hook.
You can pass the following values to the provided callback:
[true]
or['create']
will grant access to modify or create the pad if the request is for a pad, otherwise access is simply granted. Access to a pad will be downgraded to modify-only ifsettings.editOnly
is true or the user'scanCreate
setting is set tofalse
, and downgraded to read-only if the user'sreadOnly
setting istrue
.['modify']
will grant access to modify but not create the pad if the request is for a pad, otherwise access is simply granted. Access to a pad will be downgraded to read-only if the user'sreadOnly
setting istrue
.['readOnly']
will grant read-only access.[false]
will deny access.[]
orundefined
will defer the authorization decision to the next authorization plugin (if any, otherwise deny).
Example:
exports.authorize = (hookName, context, cb) => {
const user = context.req.session.user;
const path = context.req.path; // or context.resource
if (isExplicitlyProhibited(user, path)) return cb([false]);
if (isExplicitlyAllowed(user, path)) return cb([true]);
return cb([]); // Let the next authorization plugin decide
};
authenticate
Called from: src/node/hooks/express/webaccess.js
Things in context:
- req - the request object
- res - the response object
- users - the users object from settings.json (possibly modified by plugins)
- next - ?
- username - the username used (optional)
- password - the password used (optional)
This hook is called to handle authentication.
Plugins that supply an authenticate function should probably also supply an authnFailure function unless falling back to HTTP basic authentication is appropriate upon authentication failure.
This hook is only called if either the requireAuthentication
setting is true
or the request is for an /admin
page.
Calling the provided callback with [true]
or [false]
will cause
authentication to succeed or fail, respectively. Calling the callback with []
or undefined
will defer the authentication decision to the next authentication
plugin (if any, otherwise fall back to HTTP basic authentication).
If you wish to provide a mix of restricted and anonymous access (e.g., some pads are private, others are public), you can "authenticate" (as a guest account) users that have not yet logged in, and rely on other hooks (e.g., authorize, onAccessCheck, handleMessageSecurity) to authorize specific privileged actions.
If authentication is successful, the authenticate function MUST set
context.req.session.user
to the user's settings object. The username
property of this object should be set to the user's username. The settings
object should come from global settings (context.users[username]
).
Example:
exports.authenticate = (hook_name, context, cb) => {
if (notApplicableToThisPlugin(context)) {
return cb([]); // Let the next authentication plugin decide
}
const username = authenticate(context);
if (!username) {
console.warn(`ep_myplugin.authenticate: Failed authentication from IP ${context.req.ip}`);
return cb([false]);
}
console.info(`ep_myplugin.authenticate: Successful authentication from IP ${context.req.ip} for user ${username}`);
const users = context.users;
if (!(username in users)) users[username] = {};
users[username].username = username;
context.req.session.user = users[username];
return cb([true]);
};
authFailure
Called from: src/node/hooks/express/webaccess.js
Things in context:
- req - the request object
- res - the response object
- next - ?
DEPRECATED: Use authnFailure or authzFailure instead.
This hook is called to handle an authentication or authorization failure.
Plugins that supply an authenticate function should probably also supply an authnFailure function unless falling back to HTTP basic authentication is appropriate upon authentication failure.
A plugin's authFailure function is only called if all of the following are true:
- There was an authentication or authorization failure.
- The failure was not already handled by an authFailure function from another plugin.
- For authentication failures: The failure was not already handled by the authnFailure hook.
- For authorization failures: The failure was not already handled by the authzFailure hook.
Calling the provided callback with [true]
tells Etherpad that the failure was
handled and no further error handling is required. Calling the callback with
[]
or undefined
defers error handling to the next authFailure plugin (if
any, otherwise fall back to HTTP basic authentication for an authentication
failure or a generic 403 page for an authorization failure).
Example:
exports.authFailure = (hookName, context, cb) => {
if (notApplicableToThisPlugin(context)) {
return cb([]); // Let the next plugin handle the error
}
context.res.redirect(makeLoginURL(context.req));
return cb([true]);
};
preAuthzFailure
Called from: src/node/hooks/express/webaccess.js
Things in context:
- req - the request object
- res - the response object
This hook is called to handle a pre-authentication authorization failure.
A plugin's preAuthzFailure function is only called if the pre-authentication authorization failure was not already handled by a preAuthzFailure function from another plugin.
Calling the provided callback with [true]
tells Etherpad that the failure was
handled and no further error handling is required. Calling the callback with
[]
or undefined
defers error handling to a preAuthzFailure function from
another plugin (if any, otherwise fall back to a generic 403 error page).
Example:
exports.preAuthzFailure = (hookName, context, cb) => {
if (notApplicableToThisPlugin(context)) return cb([]);
context.res.status(403).send(renderFancy403Page(context.req));
return cb([true]);
};
authnFailure
Called from: src/node/hooks/express/webaccess.js
Things in context:
- req - the request object
- res - the response object
This hook is called to handle an authentication failure.
Plugins that supply an authenticate function should probably also supply an authnFailure function unless falling back to HTTP basic authentication is appropriate upon authentication failure.
A plugin's authnFailure function is only called if the authentication failure was not already handled by an authnFailure function from another plugin.
Calling the provided callback with [true]
tells Etherpad that the failure was
handled and no further error handling is required. Calling the callback with
[]
or undefined
defers error handling to an authnFailure function from
another plugin (if any, otherwise fall back to the deprecated authFailure hook).
Example:
exports.authnFailure = (hookName, context, cb) => {
if (notApplicableToThisPlugin(context)) return cb([]);
context.res.redirect(makeLoginURL(context.req));
return cb([true]);
};
authzFailure
Called from: src/node/hooks/express/webaccess.js
Things in context:
- req - the request object
- res - the response object
This hook is called to handle a post-authentication authorization failure.
A plugin's authzFailure function is only called if the authorization failure was not already handled by an authzFailure function from another plugin.
Calling the provided callback with [true]
tells Etherpad that the failure was
handled and no further error handling is required. Calling the callback with
[]
or undefined
defers error handling to an authzFailure function from
another plugin (if any, otherwise fall back to the deprecated authFailure hook).
Example:
exports.authzFailure = (hookName, context, cb) => {
if (notApplicableToThisPlugin(context)) return cb([]);
if (needsPremiumAccount(context.req) && !context.req.session.user.premium) {
context.res.status(200).send(makeUpgradeToPremiumAccountPage(context.req));
return cb([true]);
}
// Use the generic 403 forbidden response.
return cb([]);
};
handleMessage
Called from: src/node/handler/PadMessageHandler.js
Things in context:
- message - the message being handled
- socket - the socket.io Socket object
- client - deprecated synonym of socket
This hook allows plugins to drop or modify incoming socket.io messages from clients, before Etherpad processes them.
The handleMessage function must return a Promise. If the Promise resolves to
null
, the message is dropped. Returning callback(value)
will return a
Promise that is resolved to value
.
Examples:
// Using an async function:
exports.handleMessage = async (hookName, {message, socket}) => {
if (message.type === 'USERINFO_UPDATE') {
// Force the display name to the name associated with the account.
const user = socket.client.request.session.user || {};
if (user.name) message.data.userInfo.name = user.name;
}
};
// Using a regular function:
exports.handleMessage = (hookName, {message, socket}, callback) => {
if (message.type === 'USERINFO_UPDATE') {
// Force the display name to the name associated with the account.
const user = socket.client.request.session.user || {};
if (user.name) message.data.userInfo.name = user.name;
}
return callback();
};
handleMessageSecurity
Called from: src/node/handler/PadMessageHandler.js
Things in context:
- message - the message being handled
- socket - the socket.io Socket object
- client - deprecated synonym of socket
This hook allows plugins to grant temporary write access to a pad. It is called
for each incoming message from a client. If write access is granted, it applies
to the current message and all future messages from the same socket.io
connection until the next CLIENT_READY
or SWITCH_TO_PAD
message. Read-only
access is reset after each CLIENT_READY
or SWITCH_TO_PAD
message, so
granting write access has no effect for those message types.
The handleMessageSecurity function must return a Promise. If the Promise
resolves to true
, write access is granted as described above. Returning
callback(value)
will return a Promise that is resolved to value
.
Examples:
// Using an async function:
exports.handleMessageSecurity = async (hookName, {message, socket}) => {
if (shouldGrantWriteAccess(message, socket)) return true;
return;
};
// Using a regular function:
exports.handleMessageSecurity = (hookName, {message, socket}, callback) => {
if (shouldGrantWriteAccess(message, socket)) return callback(true);
return callback();
};
clientVars
Called from: src/node/handler/PadMessageHandler.js
Things in context:
- clientVars - the basic
clientVars
built by the core - pad - the pad this session is about
- socket - the socket.io Socket object
This hook is called after a client connects but before the initial configuration is sent to the client. Plugins can use this hook to manipulate the configuration. (Example: Add a tracking ID for an external analytics tool that is used client-side.)
The clientVars function must return a Promise that resolves to an object (or
null/undefined) whose properties will be merged into context.clientVars
.
Returning callback(value)
will return a Promise that is resolved to value
.
You can modify context.clientVars
to change the values sent to the client, but
beware: async functions from other clientVars plugins might also be reading or
manipulating the same context.clientVars
object. For this reason it is
recommended you return an object rather than modify context.clientVars
.
If needed, you can access the user's account information (if authenticated) via
context.socket.client.request.session.user
.
Examples:
// Using an async function
exports.clientVars = async (hookName, context) => {
const user = context.socket.client.request.session.user || {};
return {'accountUsername': user.username || '<unknown>'}
};
// Using a regular function
exports.clientVars = (hookName, context, callback) => {
const user = context.socket.client.request.session.user || {};
return callback({'accountUsername': user.username || '<unknown>'});
};
This can be accessed on the client-side using clientVars.currentYear
.
getLineHTMLForExport
Called from: src/node/utils/ExportHtml.js
Things in context:
- apool - pool object
- attribLine - line attributes
- text - line text
This hook will allow a plug-in developer to re-write each line when exporting to HTML.
Example:
var Changeset = require("ep_etherpad-lite/static/js/Changeset");
exports.getLineHTMLForExport = function (hook, context) {
var header = _analyzeLine(context.attribLine, context.apool);
if (header) {
return "<" + header + ">" + context.lineContent + "</" + header + ">";
}
}
function _analyzeLine(alineAttrs, apool) {
var header = null;
if (alineAttrs) {
var opIter = Changeset.opIterator(alineAttrs);
if (opIter.hasNext()) {
var op = opIter.next();
header = Changeset.opAttributeValue(op, 'heading', apool);
}
}
return header;
}
exportHTMLAdditionalContent
Called from: src/node/utils/ExportHtml.js
Things in context:
- padId
This hook will allow a plug-in developer to include additional HTML content in the body of the exported HTML.
Example:
exports.exportHTMLAdditionalContent = async (hookName, {padId}) => {
return 'I am groot in ' + padId;
};
stylesForExport
Called from: src/node/utils/ExportHtml.js
Things in context:
- padId - The Pad Id
This hook will allow a plug-in developer to append Styles to the Exported HTML.
Example:
exports.stylesForExport = function(hook, padId, cb){
cb("body{font-size:13.37em !important}");
}
aceAttribClasses
Called from: src/static/js/linestylefilter.js
This hook is called when attributes are investigated on a line. It is useful if you want to add another attribute type or property type to a pad.
An attributes object is passed to the aceAttribClasses hook functions instead of the usual context object. A hook function can either modify this object directly or provide an object whose properties will be assigned to the attributes object.
Example:
exports.aceAttribClasses = (hookName, attrs, cb) => {
return cb([{
sub: 'tag:sub',
}]);
};
exportFileName
Called from src/node/handler/ExportHandler.js
Things in context:
- padId
This hook will allow a plug-in developer to modify the file name of an exported pad. This is useful if you want to export a pad under another name and/or hide the padId under export. Note that the doctype or file extension cannot be modified for security reasons.
Example:
exports.exportFileName = function(hook, padId, callback){
callback("newFileName"+padId);
}
exportHtmlAdditionalTags
Called from src/node/utils/ExportHtml.js
Things in context:
- Pad object
This hook will allow a plug-in developer to include more properties and attributes to support during HTML Export. If tags are stored as ['color', 'red']
on the attribute pool, use exportHtmlAdditionalTagsWithData
instead. An Array should be returned.
Example:
// Add the props to be supported in export
exports.exportHtmlAdditionalTags = function(hook, pad, cb){
var padId = pad.id;
cb(["massive","jugs"]);
};
exportHtmlAdditionalTagsWithData
Called from src/node/utils/ExportHtml.js
Things in context:
- Pad object
Identical to exportHtmlAdditionalTags
, but for tags that are stored with a specific value (not simply true
) on the attribute pool. For example ['color', 'red']
, instead of ['bold', true]
. This hook will allow a plug-in developer to include more properties and attributes to support during HTML Export. An Array of arrays should be returned. The exported HTML will contain tags like <span data-color="red">
for the content where attributes are ['color', 'red']
.
Example:
// Add the props to be supported in export
exports.exportHtmlAdditionalTagsWithData = function(hook, pad, cb){
var padId = pad.id;
cb([["color", "red"], ["color", "blue"]]);
};
exportEtherpadAdditionalContent
Called from src/node/utils/ExportEtherpad.js and src/node/utils/ImportEtherpad.js
Things in context: Nothing
Useful for exporting and importing pad metadata that is stored in the database
but not in the pad's content or attributes. For example, in ep_comments_page the
comments are stored as comments:padId:uniqueIdOfComment
so a complete export
of all pad data to an .etherpad
file must include the comments:padId:*
records.
Example:
// Add support for exporting comments metadata
exports.exportEtherpadAdditionalContent = () => ['comments'];
userLeave
Called from src/node/handler/PadMessageHandler.js
This in context:
- session (including the pad id and author id)
This hook gets called when an author leaves a pad. This is useful if you want to perform certain actions after a pad has been edited
Example:
exports.userLeave = function(hook, session, callback) {
console.log('%s left pad %s', session.author, session.padId);
};
clientReady
Called from src/node/handler/PadMessageHandler.js
This in context:
- message
This hook gets called when handling a CLIENT_READY which is the first message from the client to the server.
Example:
exports.clientReady = function(hook, message) {
console.log('Client has entered the pad' + message.padId);
};