-The application framework daemons
-=================================
+# The application framework
-Foreword
---------
+## Introduction
-This document describes application framework daemons
-FCS (Fully Conform to Specification) implementation is still under development.
-It may happen that current implementation somehow diverges with specifications.
+The daemon ***afm-system-daemon*** handle applications life.
+Understand that they will manage operations that mainly are:
-Introduction
-------------
-
-Daemons ***afm-user-daemon*** and ***afm-system-daemon*** handle applications
-life. Understand that they will manage operations like:
-
- - ***installation***
- - ***uninstallation***
- - ***running***
- - ***suspend***
- - ***inventory***
- - ...
+- ***installation***
+- ***uninstallation***
+- ***running***
+- ***terminating***
+- ***inventory***
In addition, they ensure that operations use the security framework as needed
and that applications are executed in the correct context.
-***D-Bus*** is in charge of transmitting orders to the appropriate daemon
-depending upon ***D-Bus*** destination.
-
-The figure below summarizes the situation of both **afm-system-daemon** and
-**afm-user-daemon** in the system.
-
-![afm-daemons][afm-daemons]
-
-The D-Bus interface
--------------------
-
-### Overview of the dbus interface
-
-The ***afm daemons*** takes theirs orders from the session instance
-of D-Bus. The use of D-Bus is great because it allows to implement
-discovery and signaling.
-
-The dbus session is by default addressed by environment
-variable *DBUS_SESSION_BUS_ADDRESS*. Using **systemd**
-variable *DBUS_SESSION_BUS_ADDRESS* is automatically set for
-user sessions.
-
-They are listening with the destination name ***org.AGL.afm.[user|system]***
-at the object of path ***/org/AGL/afm/[user|system]*** on the interface
-***org.AGL.afm.[user|system]*** for the below detailed members for the
-***afm-system-daemon***:
-
- - ***install***
- - ***uninstall***
-
-And for ***afm-user-daemon***:
-
- - ***runnables***
- - ***detail***
- - ***start***
- - ***once***
- - ***terminate***
- - ***pause***
- - ***resume***
- - ***runners***
- - ***state***
- - ***install***
- - ***uninstall***
-
-D-Bus is mainly used for signaling and discovery. Its optimized
-typed protocol is not used except for transmitting only one string
-in both directions.
-
-The client and the service are using JSON serialization to
-exchange data. Signature of any member of the D-Bus interface is
-***string -> string*** for ***JSON -> JSON***. This is the normal case, if there
-is an error, current implementation returns a dbus error that is a string.
-
-Here are examples using *dbus-send*, here to install an application from a
-widget file:
-
- dbus-send --session --print-reply \
- --dest=org.AGL.afm.system \
- /org/AGL/afm/system \
- org.AGL.afm.system.install 'string:"/tmp/appli.wgt"
-
-
-And here, to query data on installed applications that can be run:
-
- dbus-send --session --print-reply \
- --dest=org.AGL.afm.user \
- /org/AGL/afm/user \
- org.AGL.afm.user.runnables string:true
-
-### The protocol over D-Bus
-
-On all following sub-chapters we assume that we talk about either
-***afm-system-daemon*** or ***afm-user-daemon***. Method and D-Bus parameters
-are considered as self-explanatory.
-
-The D-Bus interface is defined by:
-
- * **DESTINATION**: org.AGL.afm.[user|system]
-
- * **PATH**: /org/AGL/afm/[user|system]
-
- * **INTERFACE**: org.AGL.afm.[user|system]
-
-#### Method org.AGL.afm.system.install
-
-**Description**: Install an application from a widget file.
-
-When an application with the same *id* and *version* already exists. Outside of
-using *force=true* the application is not reinstalled.
-
-Applications are installed the subdirectories of applications common directory.
-If *root* is specified, the application is installed under the
-sub-directories of the *root* defined.
-
-Note that this methods is a simple accessor method of
-***org.AGL.afm.system.install*** from ***afm-system-daemon***.
-
-After the installation and before returning to the sender,
-***afm-system-daemon*** sends a signal ***org.AGL.afm.system.changed***.
-
-**Input**: The *path* of the widget file to install and, optionally,
-a flag to *force* reinstallation, and, optionally, a *root* directory.
-
-Either just a string being the absolute path of the widget file:
-
- "/a/path/driving/to/the/widget"
-
-Or an object:
-
- {
- "wgt": "/a/path/to/the/widget",
- "force": false,
- "root": "/a/path/to/the/root"
- }
-
-"wgt" and "root" must be absolute paths.
-
-**output**: An object with the field "added" being the string for
-the id of the added application.
-
- {"added":"appli@x.y"}
-
----
-
-#### Method org.AGL.afm.system.uninstall
-
-**Description**: Uninstall an application from its id.
-
-
-Note that this methods is a simple method accessor of
-***org.AGL.afm.system.uninstall*** from ***afm-system-daemon***.
-
-After the uninstallation and before returning to the sender,
-***afm-system-daemon*** sends a signal ***org.AGL.afm.system.changed***.
-
-**Input**: the *id* of the application and optionally the application *root* path.
-
-Either a string:
-
- "appli@x.y"
-
-Or an object:
-
- {
- "id": "appli@x.y",
- "root": "/a/path/to/the/root"
- }
-
-**output**: the value 'true'.
-
----
-
-#### Method org.AGL.afm.user.detail
-
-
-**Description**: Get details about an application from its id.
-
-**Input**: the id of the application as below.
-
-Either just a string:
-
- "appli@x.y"
-
-Or an object having the field "id" of type string:
-
- {"id":"appli@x.y"}
-
-**Output**: A JSON object describing the application containing
-the fields described below.
-
- {
- "id": string, the application id (id@version)
- "version": string, the version of the application
- "width": integer, requested width of the application
- "height": integer, resqueted height of the application
- "name": string, the name of the application
- "description": string, the description of the application
- "shortname": string, the short name of the application
- "author": string, the author of the application
- }
-
----
-
-#### Method org.AGL.afm.user.runnables
-
-**Description**: Get the list of applications that can be run.
-
-**Input**: any valid json entry, can be anything except null.
-
-**output**: An array of description of the runnable applications.
-Each item of the array contains an object containing the detail of
-an application as described above for the method
-*org.AGL.afm.user.detail*.
-
----
-
-#### Method org.AGL.afm.user.install
-
-**Description**: Install an application from its widget file.
-
-If an application of the same *id* and *version* exists, it is not
-reinstalled except when *force=true*.
-
-Applications are installed in the subdirectories of the common directory
-reserved for applications.
-If *root* is specified, the application is installed under
-sub-directories of defined *root*.
-
-Note that this methods is a simple accessor to the method
-***org.AGL.afm.system.install*** of ***afm-system-daemon***.
-
-After the installation and before returning to the sender,
-***afm-user-daemon*** sends the signal ***org.AGL.afm.user.changed***.
-
-**Input**: The *path* of widget file to be installed. Optionally,
-a flag to *force* reinstallation and/or a *root* directory.
-
-Simple form a simple string containing the absolute widget path:
-
- "/a/path/driving/to/the/widget"
-
-Or an object:
-
- {
- "wgt": "/a/path/to/the/widget",
- "force": false,
- "root": "/a/path/to/the/root"
- }
-
-***wgt*** and ***root*** MUST be absolute paths.
-
-**output**: An object containing field "added" to use as application ID.
-
- {"added":"appli@x.y"}
+The daemon ***afm-system-daemon*** is accessible through AGL
+micro-service architecture using either the binder ***afb-binder*** or
+the client library ***libafbwsc***.
----
+## Starting **afm-system-daemon**
-#### Method org.AGL.afm.user.uninstall
+***afm-system-daemon*** is launched by systemd services.
+Normally, service files are located in the directory
+*/lib/systemd/system/afm-system-daemon.service*.
-**Description**: Uninstall an application from its id.
+Internally, the daemon is built as a binding served by afb-daemon.
-
-Note that this methods is a simple accessor to
-***org.AGL.afm.system.uninstall*** method from ***afm-system-daemon***.
-
-After the uninstallation and before returning to the sender,
-***afm-user-daemon*** sends the signal ***org.AGL.afm.user.changed***.
-
-**Input**: the *id* of the application and, optionally, the path to
-application *root*.
-
-Either a string:
-
- "appli@x.y"
-
-Or an object:
-
- {
- "id": "appli@x.y",
- "root": "/a/path/to/the/root"
- }
-
-**output**: the value 'true'.
-
----
-
-#### Method org.AGL.afm.user.start
-
-**Description**:
-
-**Input**: the *id* of the application and, optionally, the
-start *mode* as below.
-
-Either just a string:
-
- "appli@x.y"
-
-Or an object containing field "id" of type string and
-optionally a field mode:
-
- {"id":"appli@x.y","mode":"local"}
-
-The field "mode" is a string equal to either "local" or "remote".
-
-[Currently the mode is not available in the systemd version]
-
-**output**: The *runid* of the application launched. *runid* is an integer.
-
----
-
-#### Method org.AGL.afm.user.once
-
-**Description**:
-
-**Input**: the *id* of the application
-
-Either just a string:
-
- "appli@x.y"
-
-Or an object containing field "id" of type string.
-
- {"id":"appli@x.y"}
-
-**output**: The *state* of the application retrieved or launched.
-See *org.AGL.afm.user.state* to get a description of the returned
-object.
-
----
-
-#### Method org.AGL.afm.user.terminate
-
-**Description**: Terminates the application attached to *runid*.
-
-**Input**: The *runid* (an integer) of running instance to terminate.
-
-**output**: the value 'true'.
-
----
-
-#### Method org.AGL.afm.user.stop
-
-Obsolete since 8th November 2016 (2016/11/08).
-Kept for compatibility.
-
-Use **org.AGL.afm.user.pause** instead.
-
----
-
-#### Method org.AGL.afm.user.continue
-
-Obsolete since 8th November 2016 (2016/11/08).
-Kept for compatibility.
-
-Use **org.AGL.afm.user.resume** instead.
-
----
-
-#### Method org.AGL.afm.user.pause
-
-[Currently not available in the systemd version]
-
-**Description**: Pauses the application attached to *runid* until terminate or resume.
-
-**Input**: The *runid* (integer) of the running instance to pause.
-
-**output**: the value 'true'.
-
----
-
-#### Method org.AGL.afm.user.resume
-
-[Currently not available in the systemd version]
-
-**Description**: Resumes the application attached to *runid* previously paused.
-
-**Input**: The *runid* (integer) of the running instance to resume.
-
-**output**: the value 'true'.
-
----
-
-#### Method org.AGL.afm.user.state
-
-**Description**: Get informations about a running instance of *runid*.
-
-**Input**: The *runid* (integer) of the running instance inspected.
-
-**output**: An object describing instance state. It contains:
-the runid (integer), the pids of the processes as an array starting
-with the group leader, the id of the running application (string),
-the state of the application (string either: "starting", "running", "paused").
-
-Example of returned state:
-
- {
- "runid": 2,
- "pids": [ 435, 436 ],
- "state": "running",
- "id": "appli@x.y"
- }
-
----
-
-#### Method org.AGL.afm.user.runners
-
-**Description**: Get the list of currently running instances.
-
-**Input**: anything.
-
-**output**: An array of states, one per running instance, as returned by
-the method ***org.AGL.afm.user.state***.
-
-Starting **afm daemons**
-----------------------
-
-***afm-system-daemon*** and ***afm-user-daemon*** are launched as systemd
-services attached to system and user respectively. Normally, service files are
-locatedat */lib/systemd/system/afm-system-daemon.service* and
-*/usr/lib/systemd/user/afm-user-daemon.service*.
-
-### ***afm-system-daemon*** options
-
-The options for launching **afm-system-daemon** are:
-
- -r
- --root directory
-
- Set the root application directory.
-
- Note that the default root directory is defined
- to be /usr/share/afm/applications (may change).
-
- -d
- --daemon
-
- Daemonizes the process. It is not needed by sytemd.
-
- -q
- --quiet
-
- Reduces the verbosity (can be repeated).
-
- -v
- --verbose
-
- Increases the verbosity (can be repeated).
-
- -h
- --help
-
- Prints a short help.
-
-### ***afm-user-daemon*** options
-
-The options for launching **afm-user-daemon** are:
-
- -a
- --application directory
-
- [Currently not available in the systemd version]
-
- Includes the given application directory to
- the database base of applications.
-
- Can be repeated.
-
- -r
- --root directory
-
- [Currently not available in the systemd version]
-
- Includes root application directory or directories when
- passing multiple rootdir to
- applications database.
-
- Note that default root directory for
- applications is always added. In current version
- /usr/share/afm/applications is used as default.
-
- -m
- --mode (local|remote)
-
- [Currently not available in the systemd version]
-
- Set the default launch mode.
- The default value is 'local'
-
- -d
- --daemon
-
- Daemonizes the process. It is not needed by sytemd.
-
- -q
- --quiet
-
- Reduces the verbosity (can be repeated).
-
- -v
- --verbose
-
- Increases the verbosity (can be repeated).
-
- -h
- --help
-
- Prints a short help.
-
-Tasks of **afm-user-daemon**
-----------------------------
+## Tasks of **afm-system-daemon**
### Maintaining list of applications
-At start **afm-user-daemon** scans the directories containing
-applications and load in memory a list of avaliable applications
+At start **afm-system-daemon** scans the directories containing
+applications and load in memory a list of available applications
accessible by current user.
-When **afm-system-daemon** installs or removes an application.
-On success it sends the signal *org.AGL.afm.system.changed*.
-When receiving such a signal, **afm-user-daemon** rebuilds its
+When **afm-system-daemon** installs or removes an application,
+on success it sends the signal **.
+When receiving such a signal, **afm-system-daemon** rebuilds its
applications list.
-**afm-user-daemon** provides the data it collects about
-applications to its clients. Clients may either request the full list
-of avaliable applications or a more specific information about a
+**afm-system-daemon** provides the data it collects about
+applications to its clients.
+Clients may either request the full list
+of available applications or a more specific information about a
given application.
### Launching application
-**afm-user-daemon** launches application by using systemd.
+**afm-system-daemon** launches application by using systemd.
Systemd builds a secure environment for the application
before starting it.
Once launched, running instances of application receive
-a runid that identify them. To make interface with systemd
-evident, the pid is the runid.
+a runid that identify them. On previous versions, the *runid*
+had a special meaning. The current version uses the linux *PID*
+of the launched process as *runid*.
### Managing instances of running applications
-**afm-user-daemon** manages the list of applications
+**afm-system-daemon** manages the list of applications
that it launched.
When owning the right permissions, a client can get the list
of running instances and details about a specific
-running instance. It can also terminate a given application.
+running instance.
+It can also terminate a given application.
### Installing and uninstalling applications
If the client own the right permissions,
-**afm-user-daemon** delegates that task
+**afm-system-daemon** delegates that task
to **afm-system-daemon**.
-Using ***afm-util***
---------------------
-
-The command line tool ***afm-util*** uses dbus-send to send
-orders to **afm-user-daemon**. This small scripts allows to
-send command to ***afm-user-daemon*** either interactively
-at shell prompt or scriptically.
+## Using ***afm-util***
-The syntax is simple: it accept a command and when requires attached arguments.
+The command line tool ***afm-util*** is available in devel mode.
-Here is the summary of ***afm-util***:
-
- - **afm-util runnables **:
-
- list the runnable widgets installed
-
- - **afm-util install wgt **:
-
- install the wgt file
+It uses afb-client-demo to send orders to **afm-system-daemon**.
+This small scripts allows to send command to ***afm-system-daemon*** either
+interactively at shell prompt or scriptically.
- - **afm-util uninstall id **:
+The syntax is simple:
- remove the installed widget of id
+- it accept a command and when requires attached arguments.
- - **afm-util detail id **:
-
- print detail about the installed widget of id
-
- - **afm-util runners **:
-
- list the running instance
+Here is the summary of ***afm-util***:
- - **afm-util start id **:
+- **afm-util runnables **:
+ list the runnable widgets installed
- start an instance of the widget of id
+- **afm-util install wgt **:
+ install the wgt file
- - **afm-util once id **:
+- **afm-util uninstall id **:
+ remove the installed widget of id
- run once an instance of the widget of id
+- **afm-util detail id **:
+ print detail about the installed widget of id
- - **afm-util terminate rid **:
+- **afm-util runners **:
+ list the running instance
- terminate the running instance rid
+- **afm-util start id **:
+ start an instance of the widget of id
- - **afm-util state rid **:
+- **afm-util once id **:
+ run once an instance of the widget of id
- get status of the running instance rid
+- **afm-util terminate rid **:
+ terminate the running instance rid
+- **afm-util state rid **:
+ get status of the running instance rid
Here is how to list applications using ***afm-util***:
+```bash
afm-util runnables
-
+```
[afm-daemons]: pictures/afm-daemons.svg