diff --git a/.env.example b/.env.example
index e69de29..b37f586 100644
--- a/.env.example
+++ b/.env.example
@@ -0,0 +1,5 @@
+WHEREIS_API_BASE_URL=https://api-whereis.thegux.fr
+WHEREIS_API_EMAIL=
+WHEREIS_API_PASSWORD=
+
+WHEREIS_CERT_VERIFY=true
\ No newline at end of file
diff --git a/Makefile b/Makefile
index 7d31afe..29e7ba2 100644
--- a/Makefile
+++ b/Makefile
@@ -22,4 +22,4 @@ build: check
 	$(PYTHON) -m hatch -v build -t wheel
 
 publish: build
-	$(PYTHON) -m twine upload --repository gitea dist/*.whl
\ No newline at end of file
+	$(PYTHON) -m twine upload --repository whereis-client dist/*.whl
\ No newline at end of file
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..62754b3
--- /dev/null
+++ b/README.md
@@ -0,0 +1,33 @@
+# whereis-client
+
+A simple Python client library to interact easyly with the WhereIs REST API.
+
+## Install
+
+```bash
+pip install --index-url https://gitea.thegux.fr/api/packages/rmanach/pypi/simple/ whereis-client==<version> --extra-index-url https://pypi.org/simple
+```
+
+## How to ?
+In order to use the client you need to provide some environments variables defined in `.env.example`. You can either:
+- Copy the `.env.example` into `.env` and feed the variables (`.env` should be next to your main script using the lib)
+- Add those environments variables to your environment profile.
+
+Once it's done, you're good to use the client.
+
+```python
+from whereis_client import Client
+
+cli = Client.from_env()
+lst_gps_positions = cli.get_gps_positions(
+    date_start="2022-12-25", date_end="2022-12-30"
+)
+```
+
+For some code samples on how to use the client, take a look at the [main.py](main.py) sample script.
+
+Enjoy !
+
+## Contact
+
+If you have any issues, feel free to contact **admin@thegux.fr** for fixes or upgrades.
diff --git a/main.py b/main.py
index 7040273..5da3376 100644
--- a/main.py
+++ b/main.py
@@ -1,7 +1,10 @@
 import logging
 import sys
+import json
+import time
 
-from src import VERSION
+from src import VERSION, Client, OrderField
+from src.exceptions import WhereIsException, UnauthorizedException
 
 
 stdout_handler = logging.StreamHandler(stream=sys.stdout)
@@ -12,5 +15,113 @@ logging.basicConfig(
 )
 
 if __name__ == "__main__":
+    """
+    This a sample script to demonstrate how to deal with WhereIs API client.
+
+    All you need is to provide some environments variables describe in the `.env.example`.
+    You can:
+    - Copy `.env.example` into `.env` and feed env variables or,
+    - Directly export those mandatories variables
+
+    Once its done, you can initialize the Client:
+
+    cli = Client.from_env()
+
+    and use all the available methods to interact with the WhereIs API.
+
+    Sessions:
+        - create_session
+        - get_sessions
+        - get_session
+        - update_session
+        - delete_session
+        - update_session_users
+        - close_session
+        - watch_session_events
+        - stop_watch_session
+    WS token:
+        - get_wstokens
+        - create_wstoken
+        - delete_wstoken
+    GPS positions:
+        - get_gps_positions
+    """
     logging.info(f"WhereIs client v{VERSION}")
 
+    # initialize the client
+    try:
+        cli = Client.from_env()
+    except WhereIsException as e:
+        logging.error(f"unable to initialize WhereIs API client: {e}")
+    except Exception as e:
+        logging.error("unexpected error occurred while initializing client", exc_info=True)
+
+    # get ws tokens
+    tokens = cli.get_wstokens()
+    print(json.dumps(tokens, indent=2))
+
+    # delete ws token
+    if len(tokens) > 0:
+        token = cli.delete_wstoken(tokens[0].get("id"))
+        print(json.dumps(tokens, indent=2))
+    
+    # create ws token
+    try:
+        token = cli.create_wstoken()
+    except WhereIsException as e:
+        logging.error(f"error occurred while creating a ws token, status code: {e.error_code}")
+        print(json.dumps(e.content, indent=2))
+
+    # retrieve all user/public sessions
+    sessions = cli.get_sessions()
+    print(json.dumps(sessions, indent=2))
+
+    # create and update a session (must have `Streamer` role)
+    try:
+        session = cli.create_session(name="RUN-01")
+        session = cli.update_session(session.get("id"), name="RUN-02", description="My second run")
+    except WhereIsException as e:
+        logging.error(f"error occurred while creating/updating a session, status code: {e.error_code}")
+        print(json.dumps(e.content, indent=2))
+
+    # retrieve all user/public sessions with ordering
+    sessions = cli.get_sessions(ordering=OrderField.AscDateStart)
+    print(json.dumps(sessions, indent=2))
+
+    # retrieve all user/public sessions with search
+    sessions = cli.get_sessions(search="run", ordering=OrderField.AscDateStart)
+    print(json.dumps(sessions, indent=2))
+
+    # retrieve session by id
+    session = cli.get_session(session.get("id"))
+    print(json.dumps(session, indent=2))
+
+    # update session users
+    try:
+        session = cli.update_session_users(session.get("id"), [])
+    except WhereIsException as e:
+        logging.error(f"error occurred while updating users session, status code: {e.error_code}")
+        print(json.dumps(e.content, indent=2))
+
+    # close a session
+    try:
+        session = cli.close_session("does-not-exist")
+    except WhereIsException as e:
+        logging.error(f"error occurred while closing session, status code: {e.error_code}")
+        print(json.dumps(e.content, indent=2))
+
+    # get session events
+    cli.watch_session_events(session.get("id"))
+
+    # get gps positions from "2024-12-25T23:00:00" to infinity...
+    gps_positions = cli.get_gps_positions(date_start="2024-12-25T23:00:00")
+    print(json.dumps(gps_positions, indent=2))
+
+    # close the session
+    session = cli.close_session(session.get("id"))
+
+    # delete a session
+    cli.delete_session(session.get("id"))
+
+    # stop session events watcher
+    cli.stop_watch_session(session.get("id"), force=True)
diff --git a/pyproject.toml b/pyproject.toml
index 8b96326..fe053d3 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -8,6 +8,8 @@ dynamic = ["version"]
 description = "WhereIs API client library"
 dependencies = [
 	"requests==2.32.3",
+	"python-dotenv==1.0.1",
+	"sseclient-py==1.8.0",
 ]
 
 [tool.hatch.version]
@@ -20,7 +22,7 @@ packages = ["src"]
 only-include = ["src"]
 
 [tool.hatch.build.targets.wheel.sources]
-"src" = "whereis-client"
+"src" = "whereis_client"
 
 [tool.ruff]
 select = ["E", "F", "I"]
diff --git a/requirements.txt b/requirements.txt
index 1786051..b67a478 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1,3 @@
 requests==2.32.3
-python-dotenv==1.0.1
\ No newline at end of file
+python-dotenv==1.0.1
+sseclient-py==1.8.0
\ No newline at end of file
diff --git a/src/__init__.py b/src/__init__.py
index 1cf6267..d714875 100644
--- a/src/__init__.py
+++ b/src/__init__.py
@@ -1 +1,5 @@
+from .client import Client, OrderField
+
+__all__ = ["Client", "OrderField"]
+
 VERSION = "0.1.0"
diff --git a/src/client.py b/src/client.py
new file mode 100644
index 0000000..6fbd58b
--- /dev/null
+++ b/src/client.py
@@ -0,0 +1,550 @@
+import logging
+import os
+from dataclasses import dataclass, field
+from datetime import datetime as dt
+from enum import Enum
+from threading import Event, Thread
+from typing import Any, Callable
+from urllib.parse import urljoin
+from uuid import UUID
+
+import requests
+import urllib3
+from dotenv import dotenv_values
+from requests import Session
+from sseclient import SSEClient
+
+from .exceptions import UnauthorizedException, WhereIsException
+
+API_DEFAULT_URL = "https://api-whereis.thegux.fr"
+
+__all__ = ["Client", "OrderField"]
+
+
+def refresh():
+    """
+    Catch 401 status code (UnauthorizedException)
+    refresh the access token and retry.
+    """
+
+    def decorator(func):
+        def wrapper(*args, **kwargs):
+            if len(args) > 0 and isinstance(args[0], Client):
+                for i in range(2):
+                    try:
+                        return func(*args, **kwargs)
+                    except UnauthorizedException as e:
+                        if i == 1:  # second attempt
+                            logging.error(
+                                "second call attempt failed after refreshing token"
+                            )
+                            raise e
+                        logging.warning("refresh access token...")
+                        args[0]._refresh()
+
+        return wrapper
+
+    return decorator
+
+
+class OrderField(Enum):
+    """
+    Ordering query param available fields.
+
+    - AscDateStart: date start ascending order
+    - DesDateStart: date start descending order
+    - AscDateEnd: date end ascending order
+    - DesDateEnd: date end descending order
+    """
+
+    AscDateStart = "date_start"
+    DesDateStart = "-date_start"
+    AscDateEnd = "date_end"
+    DesDateEnd = "-date_end"
+
+
+@dataclass(frozen=True, slots=True)
+class SessionWatcher:
+    """
+    Handle the SSE client connection in a daemon thread.
+
+    NOTE: Should not be instanciated directly, use
+    the `Client` instead.
+    """
+
+    session_id: UUID
+    _thread: Thread
+    _client: SSEClient
+    _event: Event
+
+    @classmethod
+    def from_session_id(
+        cls,
+        base_url: str,
+        id_: UUID,
+        headers: dict[str, Any],
+        callback: Callable[[str], None] | None = None,
+        verify: bool = True,
+    ) -> "SessionWatcher":
+        session_url = urljoin(base_url, f"/sessions/{id_}/events/")
+
+        headers = {**headers, "Accept": "text/event-stream"}
+        resp = requests.get(session_url, stream=True, headers=headers, verify=verify)
+        client = SSEClient(resp)  # type: ignore
+        event = Event()
+
+        def _job():
+            logging.debug(f"SSE client daemon started for session: {id_}")
+
+            for evt in client.events():
+                logging.debug(f"event received for session: {id_}")
+                if callback is not None:
+                    callback(evt.data)
+
+                if event.is_set():
+                    logging.debug(f"SSE client daemon stopped for session: {id_}")
+                    break
+
+        t = Thread(target=_job, daemon=True)
+        t.start()
+
+        return SessionWatcher(id_, t, client, event)
+
+    def stop(self, force: bool = False):
+        """
+        Send an event to stop the events stream and wait
+        for the thread to finish.
+
+        If you want to stop the stream savagely, you can use
+        the optional arg: `force`.
+        """
+        self._event.set()
+        self._thread.join(timeout=0 if force else None)
+        logging.debug(f"SSE stream client for session: {self.session_id} closed")
+
+
+@dataclass(slots=True)
+class Client:
+    """
+    WhereIs API Client main class.
+
+    Example:
+    --------
+    cli = Client.from_env()
+    sessions = cli.get_sessions()
+    """
+
+    base_url: str
+    email: str
+    password: str
+
+    session: Session = field(init=False)
+
+    sessions_watcher: dict[UUID, SessionWatcher] = field(
+        default_factory=dict, init=False
+    )
+
+    def _login(self) -> WhereIsException | None:
+        """Get the access token and store it in the `Session` header"""
+        data = {
+            "email": self.email,
+            "password": self.password,
+        }
+
+        login_url = urljoin(self.base_url, "/auth/token/")
+        logging.info(f"login: {login_url}")
+
+        res = self.session.post(login_url, json=data)
+        if res.status_code >= 400:
+            raise WhereIsException(login_url, res)
+
+        access_token = res.json()["access"]
+        self.session.headers.update({"Authorization": f"Bearer {access_token}"})
+
+        return None
+
+    def _refresh(self) -> WhereIsException | None:
+        """Refresh the access token and store it in the `Session` header"""
+        refresh_url = urljoin(self.base_url, "/auth/refresh/")
+        logging.info(f"refresh: {refresh_url}")
+
+        res = self.session.post(refresh_url)
+        if res.status_code >= 400:
+            raise WhereIsException(refresh_url, res)
+
+        access_token = res.json()["access"]
+        self.session.headers.update({"Authorization": f"Bearer {access_token}"})
+
+        return None
+
+    @classmethod
+    def from_env(cls) -> "Client":
+        """
+        Initialize the client from env variables (.env & global) and
+        log in into the application.
+
+        If the login fails, an exception is raised.
+        """
+        env_data = {
+            "WHEREIS_API_EMAIL": os.getenv("WHEREIS_API_EMAIL", ""),
+            "WHEREIS_API_PASSWORD": os.getenv("WHEREIS_API_PASSWORD", ""),
+            "WHEREIS_API_BASE_URL": os.getenv("WHEREIS_API_BASE_URL", API_DEFAULT_URL),
+        }
+        dotenv_data = dotenv_values()
+        env_data.update(dotenv_data)  # type: ignore
+
+        cli = Client(
+            env_data.get("WHEREIS_API_BASE_URL", ""),
+            env_data.get("WHEREIS_API_EMAIL", ""),
+            env_data.get("WHEREIS_API_PASSWORD", ""),
+        )
+        cli.session = Session()
+        cli.session.headers.update({"content-type": "application/json"})
+
+        is_cert_verify = env_data.get("WHEREIS_CERT_VERIFY", "") != "false"
+        if not is_cert_verify:
+            urllib3.disable_warnings()
+
+        cli.session.verify = is_cert_verify
+
+        cli._login()
+
+        logging.info(f"client successfully initialized for user: {cli.email}")
+        return cli
+
+    @refresh()
+    def _get_sessions_page(self, url: str) -> dict[str, Any] | WhereIsException:
+        """Get paginate sessions."""
+        res = self.session.get(url)
+        if res.status_code == 401:
+            raise UnauthorizedException(url, res)
+
+        if res.status_code >= 400:
+            raise WhereIsException(url, res)
+
+        return res.json()
+
+    def get_sessions(
+        self, search: str | None = None, ordering: OrderField | None = None
+    ) -> list[dict[str, Any]] | WhereIsException:
+        """
+        Get all user and public sessions.
+        If an error occurred duning the API call an exception is raised.
+
+        Params:
+        -------
+        search: str, search sessions over username and description
+        ordering: OrderField, ordering sessions by dates
+        """
+        sessions_url = urljoin(self.base_url, "/sessions/")
+
+        has_query_param = False
+        if search is not None:
+            if not has_query_param:
+                sessions_url += "?"
+                has_query_param = True
+            sessions_url += f"search={search}"
+
+        if ordering is not None:
+            if not has_query_param:
+                sessions_url += "?"
+            else:
+                sessions_url += "&"
+            sessions_url += f"ordering={ordering.value}"
+
+        logging.info(f"get sessions: {sessions_url}")
+
+        lst_sessions = []
+        while sessions_url is not None:
+            data = self._get_sessions_page(sessions_url)
+
+            sessions_url = data.get("next")
+            lst_sessions.extend(data.get("results", []))
+
+        return lst_sessions
+
+    @refresh()
+    def get_session(self, id_: UUID) -> list[dict[str, Any]] | WhereIsException:
+        session_url = urljoin(self.base_url, f"/sessions/{id_}/")
+        logging.info(f"get session: {session_url}")
+
+        res = self.session.get(session_url)
+        if res.status_code == 401:
+            raise UnauthorizedException(session_url, res)
+
+        if res.status_code >= 400:
+            raise WhereIsException(session_url, res)
+
+        return res.json()
+
+    @refresh()
+    def create_session(
+        self, name: str, description: str | None = None, is_public: bool = False
+    ) -> dict[str, Any] | WhereIsException:
+        sessions_url = urljoin(self.base_url, "/sessions/")
+        logging.info(f"create session: {sessions_url}")
+
+        data = {"name": name, "description": description, "is_public": is_public}
+        if name is None:
+            data.pop("name")
+        if description is None:
+            data.pop("description")
+        if is_public is None:
+            data.pop("is_public")
+
+        res = self.session.post(
+            sessions_url,
+            json=data,
+        )
+
+        if res.status_code == 401:
+            raise UnauthorizedException(sessions_url, res)
+
+        if res.status_code >= 400:
+            raise WhereIsException(sessions_url, res)
+
+        return res.json()
+
+    @refresh()
+    def update_session(
+        self,
+        id_: UUID,
+        name: str | None = None,
+        description: str | None = None,
+        is_public: bool | None = None,
+    ) -> dict[str, Any] | WhereIsException:
+        session_url = urljoin(self.base_url, f"/sessions/{id_}/")
+        logging.info(f"update session: {session_url}")
+
+        data = {"name": name, "description": description, "is_public": is_public}
+        if name is None:
+            data.pop("name")
+        if description is None:
+            data.pop("description")
+        if is_public is None:
+            data.pop("is_public")
+
+        res = self.session.patch(session_url, json=data)
+
+        if res.status_code == 401:
+            raise UnauthorizedException(session_url, res)
+
+        if res.status_code >= 400:
+            raise WhereIsException(session_url, res)
+
+        return res.json()
+
+    @refresh()
+    def delete_session(self, id_: UUID) -> None | WhereIsException:
+        """
+        Close and delete the session.
+
+        NOTE: The GPS positions associated to the session are not deleted !
+        """
+        session_url = urljoin(self.base_url, f"/sessions/{id_}/")
+        logging.info(f"delete session: {session_url}")
+
+        res = self.session.delete(session_url)
+
+        if res.status_code == 401:
+            raise UnauthorizedException(session_url, res)
+
+        if res.status_code >= 400:
+            raise WhereIsException(session_url, res)
+
+        return None
+
+    @refresh()
+    def update_session_users(
+        self, id_: UUID, users: list[UUID]
+    ) -> dict[str, Any] | WhereIsException:
+        """
+        Update users sessions.
+
+        WARN: An empty users list parameter cleans all users.
+        """
+        session_url = urljoin(self.base_url, f"/sessions/{id_}/users/")
+        logging.info(f"update session users: {session_url}")
+
+        res = self.session.post(session_url, json={"users": users})
+
+        if res.status_code == 401:
+            raise UnauthorizedException(session_url, res)
+
+        if res.status_code >= 400:
+            raise WhereIsException(session_url, res)
+
+        return res.json()
+
+    @refresh()
+    def close_session(self, id_: UUID) -> dict[str, Any] | WhereIsException:
+        """Close the DEFINITIVELY the session. Users can't be added anymore."""
+        session_url = urljoin(self.base_url, f"/sessions/{id_}/close/")
+        logging.info(f"close session: {session_url}")
+
+        res = self.session.post(session_url)
+
+        if res.status_code == 401:
+            raise UnauthorizedException(session_url, res)
+
+        if res.status_code >= 400:
+            raise WhereIsException(session_url, res)
+
+        return res.json()
+
+    def watch_session_events(
+        self, id_: UUID, callback: Callable[[str], None] | None = None
+    ):
+        """
+        Watch session events through an SSE client.
+
+        It will launch a daemon thread, listening for incoming events.
+        You can use the `callback` optional argument to pass a callable
+        to deal with the events.
+
+        Example:
+        --------
+        def treat_events(evt: str):
+            # your instructions
+            print(evt)
+
+        cli.watch_session_events("session-id", treat_events)
+
+        NOTE: You have to manually manage the connection error (IO, Authentication, etc...)
+        For authentication error, you'll receive this kind of event:
+        {
+            "condition": "forbidden",
+            "text": "Permission denied to channels: session_session-id",
+            "channels": ["session_session-id"]
+        }
+        """  # noqa
+        if self.sessions_watcher.get(id_) is not None:
+            logging.warning(f"you're already watching session events: {id_}")
+            return
+
+        sw = SessionWatcher.from_session_id(
+            self.base_url,
+            id_,
+            self.session.headers,  # type: ignore
+            callback,
+            self.session.verify,  # type: ignore
+        )
+
+        logging.info(f"session events (id: {id_}) watcher started")
+        self.sessions_watcher[id_] = sw
+
+    def stop_watch_session(self, id_: UUID, force: bool = False):
+        """
+        Stop watching events for a session.
+
+        Use `force` optional argument to kill the watcher
+        instead of waiting for a graceful stop.
+        """
+        if (sw := self.sessions_watcher.get(id_)) is not None:
+            sw.stop(force)
+            del self.sessions_watcher[id_]
+            logging.info(f"session events (id: {id_}) watcher stopped")
+
+    @refresh()
+    def get_wstokens(self) -> list[dict[str, Any]] | WhereIsException:
+        wstoken_url = urljoin(self.base_url, "/auth/ws-token/")
+        logging.info(f"get ws token: {wstoken_url}")
+
+        res = self.session.get(wstoken_url)
+
+        if res.status_code == 401:
+            raise UnauthorizedException(wstoken_url, res)
+
+        if res.status_code >= 400:
+            raise WhereIsException(wstoken_url, res)
+
+        return res.json()
+
+    @refresh()
+    def create_wstoken(self) -> dict[str, Any] | WhereIsException:
+        """
+        Create a websocket JWT to authenticate your real time connection.
+
+        NOTE: only one, and only one ws token per user is allowed.
+        If it expired, delete it and create a new one.
+        """
+        wstoken_url = urljoin(self.base_url, "/auth/ws-token/")
+        logging.info(f"create ws token: {wstoken_url}")
+
+        res = self.session.post(wstoken_url)
+
+        if res.status_code == 401:
+            raise UnauthorizedException(wstoken_url, res)
+
+        if res.status_code >= 400:
+            raise WhereIsException(wstoken_url, res)
+
+        return res.json()
+
+    @refresh()
+    def delete_wstoken(self, id_: UUID) -> None | WhereIsException:
+        wstoken_url = urljoin(self.base_url, f"/auth/ws-token/{id_}/")
+        logging.info(f"delete ws token: {wstoken_url}")
+
+        res = self.session.delete(wstoken_url)
+
+        if res.status_code == 401:
+            raise UnauthorizedException(wstoken_url, res)
+
+        if res.status_code >= 400:
+            raise WhereIsException(wstoken_url, res)
+
+        return None
+
+    @refresh()
+    def _get_paginate_gps_positions(
+        self, url: str
+    ) -> dict[str, Any] | WhereIsException:
+        res = self.session.get(url)
+
+        if res.status_code == 401:
+            raise UnauthorizedException(url, res)
+
+        if res.status_code >= 400:
+            raise WhereIsException(url, res)
+
+        return res.json()
+
+    def get_gps_positions(
+        self,
+        date_start: str | None = None,
+        date_end: str | None = None,
+    ) -> list[dict[str, Any]] | ValueError | WhereIsException:
+        """
+        Gets GPS positions data.
+
+        You can get GPS positions filtered by date interval using
+        optionals arguments `date_start` and `date_end`:
+        - `date_start`: [date_start,]
+        - `date_end`: [date_end,]
+        - `date_start` & `date_end`: [date_start,date_end]
+
+        The dates formats must be in any valid ISO 8601 format otherwise
+        it will raise a ValueError.
+        """
+        gps_url = urljoin(self.base_url, "/gps/positions/")
+        lst_gps_positions: list[dict[str, Any]] = []
+
+        if date_start:
+            ds = dt.fromisoformat(date_start)
+            gps_url += f"?date_start={ds.isoformat()}"
+        if date_end:
+            de = dt.fromisoformat(date_end)
+            if date_start:
+                gps_url += f"&date_end={de.isoformat()}"
+            else:
+                gps_url += f"?date_end={de.isoformat()}"
+
+        while gps_url is not None:
+            logging.info(f"get gps data from: {gps_url}")
+
+            data = self._get_paginate_gps_positions(gps_url)
+            lst_gps_positions.extend([d for d in data["results"]])
+            gps_url = data["next"]
+
+        return lst_gps_positions
diff --git a/src/exceptions.py b/src/exceptions.py
new file mode 100644
index 0000000..9eb5cc3
--- /dev/null
+++ b/src/exceptions.py
@@ -0,0 +1,23 @@
+from requests import Response
+
+__all__ = ["WhereIsException", "UnauthorizedException"]
+
+
+class WhereIsException(Exception):
+    """Handle all WhereIs API errors."""
+
+    def __init__(self, url: str, response: Response):
+        self.url = url
+        try:
+            self.content = response.json()
+        except Exception:
+            self.content = response.content.decode()
+        super().__init__(self.content)
+        self.error_code = response.status_code
+
+    def __str__(self):
+        return f"error calling: {self.url} - {self.error_code} - {self.content}"
+
+
+class UnauthorizedException(WhereIsException):
+    pass