mirror of
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Merge branch 'docs/update_ble_mesh_index_and_translate_mqtt' into 'master'
docs: update ble mesh index and translate mqtt Closes DOC-3871 See merge request espressif/esp-idf!20866
This commit is contained in:
Wang Zi Yan
commit
e6c641c432
@ -4,42 +4,42 @@ ESP-MQTT
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Overview
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--------
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ESP-MQTT is an implementation of [MQTT](mqtt.org) protocol client (MQTT is a lightweight publish/subscribe messaging protocol).
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ESP-MQTT is an implementation of `MQTT <https://mqtt.org/>`_ protocol client. MQTT is a lightweight publish/subscribe messaging protocol.
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Features
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--------
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* Supports MQTT over TCP, SSL with mbedtls, MQTT over Websocket, MQTT over Websocket Secure.
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* Support MQTT over TCP, SSL with Mbed TLS, MQTT over WebSocket, and MQTT over WebSocket Secure
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* Easy to setup with URI
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* Multiple instances (Multiple clients in one application)
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* Support subscribing, publishing, authentication, last will messages, keep alive pings and all 3 QoS levels (it should be a fully functional client).
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* Multiple instances (multiple clients in one application)
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* Support subscribing, publishing, authentication, last will messages, keep alive pings, and all 3 Quality of Service (QoS) levels (it should be a fully functional client)
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Application Example
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-------------------
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Application Examples
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---------------------
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* :example:`protocols/mqtt/tcp`: MQTT over tcp, default port 1883
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* :example:`protocols/mqtt/ssl`: MQTT over tls, default port 8883
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* :example:`protocols/mqtt/ssl_ds`: MQTT over tls using digital signature peripheral for authentication, default port 8883.
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* :example:`protocols/mqtt/ssl_mutual_auth`: MQTT over tls using certificates for authentication, default port 8883
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* :example:`protocols/mqtt/ssl_psk`: MQTT over tls using pre-shared keys for authentication, default port 8883.
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* :example:`protocols/mqtt/ws`: MQTT over Websocket, default port 80
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* :example:`protocols/mqtt/wss`: MQTT over Websocket Secure, default port 443
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* :example:`protocols/mqtt/tcp`: MQTT over TCP, default port 1883
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* :example:`protocols/mqtt/ssl`: MQTT over TLS, default port 8883
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* :example:`protocols/mqtt/ssl_ds`: MQTT over TLS using digital signature peripheral for authentication, default port 8883
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* :example:`protocols/mqtt/ssl_mutual_auth`: MQTT over TLS using certificates for authentication, default port 8883
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* :example:`protocols/mqtt/ssl_psk`: MQTT over TLS using pre-shared keys for authentication, default port 8883
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* :example:`protocols/mqtt/ws`: MQTT over WebSocket, default port 80
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* :example:`protocols/mqtt/wss`: MQTT over WebSocket Secure, default port 443
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Configuration
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-------------
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The configuration is made by setting fields in ``esp_mqtt_client_config_t`` struct. The configuration struct has the following sub structs to configure different aspects of the client operation.
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The configuration is made by setting fields in ``esp_mqtt_client_config_t`` struct. The configuration struct has the following sub structs to configure different aspects of the client operation.
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* :cpp:member:`broker<esp_mqtt_client_config::broker>` - Allow to set address and security verification.
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* :cpp:member:`credentials<esp_mqtt_client_config::credentials>` - Client credentials for authentication.
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* :cpp:member:`session<esp_mqtt_client_config::session>` - Configuration for MQTT session aspects.
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* :cpp:member:`network<esp_mqtt_client_config::network>` - Networking related configuration.
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* :cpp:member:`network<esp_mqtt_client_config::network>` - Networking related configuration.
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* :cpp:member:`task<esp_mqtt_client_config::task>` - Allow to configure FreeRTOS task.
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* :cpp:member:`buffer<esp_mqtt_client_config::buffer>` - Buffer size for input and output.
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In the following session the most common aspects are detailed.
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In the following sections, the most common aspects are detailed.
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Broker
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^^^^^^^^^^^
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@ -48,17 +48,16 @@ Broker
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Address
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===========
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Broker address can be set by usage of ``broker.address`` struct. The configuration can be made by usage of ``uri`` field
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or the combination of ``hostname``, ``transport`` and ``port``. Optionally, `path` could be set, this field is useful in
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websocket connections.
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Broker address can be set by usage of ``broker.address`` struct. The configuration can be made by usage of ``uri`` field or the combination of ``hostname``, ``transport`` and ``port``. Optionally, ``path`` could be set, this field is useful in WebSocket connections.
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The ``uri`` field is used in the format ``scheme://hostname:port/path``.
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The ``uri`` field is used in the following format ``scheme://hostname:port/path``.
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- Curently support ``mqtt``, ``mqtts``, ``ws``, ``wss`` schemes
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- MQTT over TCP samples:
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- ``mqtt://mqtt.eclipseprojects.io``: MQTT over TCP, default port 1883:
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- ``mqtt://mqtt.eclipseprojects.io:1884`` MQTT over TCP, port 1884:
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- ``mqtt://username:password@mqtt.eclipseprojects.io:1884`` MQTT over TCP,
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- ``mqtt://mqtt.eclipseprojects.io``: MQTT over TCP, default port 1883
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- ``mqtt://mqtt.eclipseprojects.io:1884``: MQTT over TCP, port 1884
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- ``mqtt://username:password@mqtt.eclipseprojects.io:1884``: MQTT over TCP,
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port 1884, with username and password
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- MQTT over SSL samples:
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@ -66,11 +65,11 @@ The ``uri`` field is used in the following format ``scheme://hostname:port/path`
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- ``mqtts://mqtt.eclipseprojects.io``: MQTT over SSL, port 8883
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- ``mqtts://mqtt.eclipseprojects.io:8884``: MQTT over SSL, port 8884
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- MQTT over Websocket samples:
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- MQTT over WebSocket samples:
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- ``ws://mqtt.eclipseprojects.io:80/mqtt``
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- MQTT over Websocket Secure samples:
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- MQTT over WebSocket Secure samples:
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- ``wss://mqtt.eclipseprojects.io:443/mqtt``
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@ -85,15 +84,14 @@ The ``uri`` field is used in the following format ``scheme://hostname:port/path`
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esp_mqtt_client_register_event(client, ESP_EVENT_ANY_ID, mqtt_event_handler, client);
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esp_mqtt_client_start(client);
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- Note: By default mqtt client uses event loop library to post related mqtt events (connected, subscribed, published, etc.)
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.. note:: By default MQTT client uses event loop library to post related MQTT events (connected, subscribed, published, etc.).
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============
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Verification
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============
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For secure connections TLS is used, and to guarantee Broker's identity the ``broker.verification`` struct must be set.
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The broker certificate may be set in PEM or DER format. To select DER the equivalent ``_len`` field must be set,
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otherwise a NULL terminated string in PEM format should be provided to ``certificate`` field.
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For secure connections with TLS used, and to guarantee Broker's identity, the ``broker.verification`` struct must be set.
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The broker certificate may be set in PEM or DER format. To select DER, the equivalent ``_len`` field must be set. Otherwise, a null-terminated string in PEM format should be provided to ``certificate`` field.
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- Get certificate from server, example: ``mqtt.eclipseprojects.io``
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``openssl s_client -showcerts -connect mqtt.eclipseprojects.io:8883 </dev/null 2>/dev/null|openssl x509 -outform PEM >mqtt_eclipse_org.pem``
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@ -109,15 +107,15 @@ otherwise a NULL terminated string in PEM format should be provided to ``certifi
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},
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};
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To details on other fields check the Reference API and :ref:`esp_tls_server_verification`.
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For details about other fields, please check the `API Reference`_ and :ref:`esp_tls_server_verification`.
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Client Credentials
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^^^^^^^^^^^^^^^^^^
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All client related credentials are under the ``credentials`` field.
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* ``username``: pointer to the username used for connecting to the broker, can also be set by URI.
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* ``client_id``: pointer to the client id, defaults to ``ESP32_%CHIPID%`` where %CHIPID% are the last 3 bytes of MAC address in hex format
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* ``username``: pointer to the username used for connecting to the broker, can also be set by URI
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* ``client_id``: pointer to the client ID, defaults to ``ESP32_%CHIPID%`` where ``%CHIPID%`` are the last 3 bytes of MAC address in hex format
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==============
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Authentication
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@ -125,22 +123,21 @@ Authentication
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It's possible to set authentication parameters through the ``authentication`` field. The client supports the following authentication methods:
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* Using a password by setting ``authentication.password``.
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* Muthual authentication with TLS by setting ``authentication.certificate`` and ``authentication.key``, both can be provided in PEM or DER format.
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* Using secure element available in ESP32-WROOM-32SE, setting ``authentication.use_secure_element``.
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* Using Digital Signature Peripheral available in some Espressif devices, setting ``authentication.ds_data``.
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* ``authentication.password``: use a password by setting
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* ``authentication.certificate`` and ``authentication.key``: mutual authentication with TLS, and both can be provided in PEM or DER format
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* ``authentication.use_secure_element``: use secure element available in ESP32-WROOM-32SE
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* ``authentication.ds_data``: use Digital Signature Peripheral available in some Espressif devices
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Session
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^^^^^^^^^^^
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For MQTT session related configurations ``section`` fields should be used.
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For MQTT session related configurations, ``section`` fields should be used.
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=======================
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Last Will and Testament
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=======================
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MQTT allows for a last will and testament (LWT) message to notify other clients when a client ungracefully disconnects. This is configured by the following fields
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in the ``esp_mqtt_client_config_t.session.last_will``-struct.
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MQTT allows for a last will and testament (LWT) message to notify other clients when a client ungracefully disconnects. This is configured by the following fields in the ``esp_mqtt_client_config_t.session.last_will`` struct.
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* ``topic``: pointer to the LWT message topic
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* ``msg``: pointer to the LWT message
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@ -148,18 +145,18 @@ in the ``esp_mqtt_client_config_t.session.last_will``-struct.
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* ``qos``: quality of service for the LWT message
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* ``retain``: specifies the retain flag of the LWT message
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Change settings in Project Configuration Menu
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Change Settings in Project Configuration Menu
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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The settings for MQTT can be found using ``idf.py menuconfig``, under Component config -> ESP-MQTT Configuration
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The settings for MQTT can be found using ``idf.py menuconfig``, under ``Component config`` > ``ESP-MQTT Configuration``.
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The following settings are available:
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- :ref:`CONFIG_MQTT_PROTOCOL_311`: Enables 3.1.1 version of MQTT protocol
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- :ref:`CONFIG_MQTT_PROTOCOL_311`: enable 3.1.1 version of MQTT protocol
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- :ref:`CONFIG_MQTT_TRANSPORT_SSL`, :ref:`CONFIG_MQTT_TRANSPORT_WEBSOCKET`: Enables specific MQTT transport layer, such as SSL, WEBSOCKET, WEBSOCKET_SECURE
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- :ref:`CONFIG_MQTT_TRANSPORT_SSL` and :ref:`CONFIG_MQTT_TRANSPORT_WEBSOCKET`: enable specific MQTT transport layer, such as SSL, WEBSOCKET, and WEBSOCKET_SECURE
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- :ref:`CONFIG_MQTT_CUSTOM_OUTBOX`: Disables default implementation of mqtt_outbox, so a specific implementaion can be supplied
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- :ref:`CONFIG_MQTT_CUSTOM_OUTBOX`: disable default implementation of mqtt_outbox, so a specific implementation can be supplied
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Events
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@ -171,9 +168,9 @@ The following events may be posted by the MQTT client:
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* ``MQTT_EVENT_DISCONNECTED``: The client has aborted the connection due to being unable to read or write data, e.g. because the server is unavailable.
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* ``MQTT_EVENT_SUBSCRIBED``: The broker has acknowledged the client's subscribe request. The event data will contain the message ID of the subscribe message.
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* ``MQTT_EVENT_UNSUBSCRIBED``: The broker has acknowledged the client's unsubscribe request. The event data will contain the message ID of the unsubscribe message.
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* ``MQTT_EVENT_PUBLISHED``: The broker has acknowledged the client's publish message. This will only be posted for Quality of Service level 1 and 2, as level 0 does not use acknowledgements. The event data will contain the message ID of the publish message.
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* ``MQTT_EVENT_DATA``: The client has received a publish message. The event data contains: message ID, name of the topic it was published to, received data and its length. For data that exceeds the internal buffer multiple `MQTT_EVENT_DATA` will be posted and `current_data_offset` and `total_data_len` from event data updated to keep track of the fragmented message.
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* ``MQTT_EVENT_ERROR``: The client has encountered an error. `esp_mqtt_error_type_t` from `error_handle` in the event data can be used to further determine the type of the error. The type of error will determine which parts of the `error_handle` struct is filled.
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* ``MQTT_EVENT_PUBLISHED``: The broker has acknowledged the client's publish message. This will only be posted for QoS level 1 and 2, as level 0 does not use acknowledgements. The event data will contain the message ID of the publish message.
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* ``MQTT_EVENT_DATA``: The client has received a publish message. The event data contains: message ID, name of the topic it was published to, received data and its length. For data that exceeds the internal buffer, multiple ``MQTT_EVENT_DATA`` will be posted and ``current_data_offset`` and ``total_data_len`` from event data updated to keep track of the fragmented message.
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* ``MQTT_EVENT_ERROR``: The client has encountered an error. ``esp_mqtt_error_type_t`` from ``error_handle`` in the event data can be used to further determine the type of the error. The type of error will determine which parts of the ``error_handle`` struct is filled.
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API Reference
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-------------
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@ -225,6 +225,7 @@ ESP-BLE-MESH 示例
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* ESP-BLE-MESH 节点控制台 - 该演示实现 ESP-BLE-MESH 节点的基本功能。在演示中，Provisioner and Node 可以扫描、验证节点，节点可以回复 Provisioner 的获取/设置消息，示例请见：:example:`example code <bluetooth/esp_ble_mesh/ble_mesh_console>`。
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.. _esp-ble-mesh-demo-videos:
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ESP-BLE-MESH 演示视频
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@ -1 +1,178 @@
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.. include:: ../../../en/api-reference/protocols/mqtt.rst
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ESP-MQTT
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========
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概述
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--------
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ESP-MQTT 是 `MQTT <https://mqtt.org/>`_ 协议客户端的实现。MQTT 是一种基于发布/订阅模式的轻量级消息传输协议。
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特性
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--------
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* 支持基于 TCP 的 MQTT、基于 Mbed TLS 的 SSL、基于 WebSocket 的 MQTT 以及基于 WebSocket Secure 的 MQTT
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* 通过 URI 简化配置流程
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* 多个实例（一个应用程序中有多个客户端）
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* 支持订阅、发布、认证、遗嘱消息、保持连接心跳机制以及 3 个服务质量 (QoS) 级别（组成全功能客户端）
|
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|
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应用示例
|
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-------------------
|
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|
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* :example:`protocols/mqtt/tcp`：基于 TCP 的 MQTT，默认端口 1883
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* :example:`protocols/mqtt/ssl`：基于 TLS 的 MQTT，默认端口 8883
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* :example:`protocols/mqtt/ssl_ds`：基于 TLS 的 MQTT，使用数字签名外设进行身份验证，默认端口 8883
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* :example:`protocols/mqtt/ssl_mutual_auth`：基于 TLS 的 MQTT，使用证书进行身份验证，默认端口 8883
|
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* :example:`protocols/mqtt/ssl_psk`：基于 TLS 的 MQTT，使用预共享密钥进行身份验证，默认端口 8883
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* :example:`protocols/mqtt/ws`：基于 WebSocket 的 MQTT，默认端口 80
|
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* :example:`protocols/mqtt/wss`：基于 WebSocket Secure 的 MQTT，默认端口 443
|
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|
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|
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配置
|
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-------------
|
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|
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通过设置 ``esp_mqtt_client_config_t`` 结构体中的字段来进行配置。配置结构体包含以下子结构体，用于配置客户端的多种操作。
|
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|
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* :cpp:member:`broker<esp_mqtt_client_config::broker>` - 允许设置地址和安全验证。
|
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* :cpp:member:`credentials<esp_mqtt_client_config::credentials>` - 用于身份验证的客户端凭据。
|
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* :cpp:member:`session<esp_mqtt_client_config::session>` - MQTT 会话相关配置。
|
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* :cpp:member:`network<esp_mqtt_client_config::network>` - 网络相关配置。
|
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* :cpp:member:`task<esp_mqtt_client_config::task>` - 允许配置 FreeRTOS 任务。
|
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* :cpp:member:`buffer<esp_mqtt_client_config::buffer>` - 输入输出的缓冲区大小。
|
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|
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下文将详细介绍不同配置。
|
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|
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服务器
|
||||
^^^^^^^^^^^^
|
||||
|
||||
===========
|
||||
地址
|
||||
===========
|
||||
|
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通过 ``broker.address`` 结构体的 ``uri`` 字段或者 ``hostname``、``transport`` 以及 ``port`` 的组合，可以设置服务器地址。您也可以选择设置 ``path``，该字段对 WebSocket 连接而言非常有用。
|
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|
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使用 ``uri`` 字段的格式为 ``scheme://hostname:port/path``。
|
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|
||||
- 当前支持 ``mqtt``、``mqtts``、``ws`` 和 ``wss`` 协议
|
||||
- 基于 TCP 的 MQTT 示例：
|
||||
|
||||
- ``mqtt://mqtt.eclipseprojects.io``：基于 TCP 的 MQTT，默认端口 1883
|
||||
- ``mqtt://mqtt.eclipseprojects.io:1884``：基于 TCP 的 MQTT，端口 1884
|
||||
- ``mqtt://username:password@mqtt.eclipseprojects.io:1884``：基于 TCP 的 MQTT，
|
||||
端口 1884，带有用户名和密码
|
||||
|
||||
- 基于 SSL 的 MQTT 示例：
|
||||
|
||||
- ``mqtts://mqtt.eclipseprojects.io``：基于 SSL 的 MQTT，端口 8883
|
||||
- ``mqtts://mqtt.eclipseprojects.io:8884``：基于 SSL 的 MQTT，端口 8884
|
||||
|
||||
- 基于 WebSocket 的 MQTT 示例：
|
||||
|
||||
- ``ws://mqtt.eclipseprojects.io:80/mqtt``
|
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|
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- 基于 WebSocket Secure 的 MQTT 示例：
|
||||
|
||||
- ``wss://mqtt.eclipseprojects.io:443/mqtt``
|
||||
|
||||
- 最简配置：
|
||||
|
||||
.. code:: c
|
||||
|
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const esp_mqtt_client_config_t mqtt_cfg = {
|
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.broker.address.uri = "mqtt://mqtt.eclipseprojects.io",
|
||||
};
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esp_mqtt_client_handle_t client = esp_mqtt_client_init(&mqtt_cfg);
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esp_mqtt_client_register_event(client, ESP_EVENT_ANY_ID, mqtt_event_handler, client);
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esp_mqtt_client_start(client);
|
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|
||||
.. note:: 默认情况下，MQTT 客户端使用事件循环库来发布相关 MQTT 事件（已连接、已订阅、已发布等）。
|
||||
|
||||
=============
|
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验证
|
||||
=============
|
||||
|
||||
为验证服务器身份，对于使用 TLS 的安全链接，必须设置 ``broker.verification`` 结构体。
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服务器证书可设置为 PEM 或 DER 格式。如要选择 DER 格式，必须设置等效 ``_len`` 字段，否则应在 ``certificate`` 字段传入以空字符结尾的 PEM 格式字符串。
|
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|
||||
- 从服务器获取证书，例如：``mqtt.eclipseprojects.io``
|
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``openssl s_client -showcerts -connect mqtt.eclipseprojects.io:8883 </dev/null 2>/dev/null|openssl x509 -outform PEM >mqtt_eclipse_org.pem``
|
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- 检查示例应用程序：``examples/mqtt_ssl``
|
||||
- 配置：
|
||||
|
||||
.. code:: c
|
||||
|
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const esp_mqtt_client_config_t mqtt_cfg = {
|
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.broker = {
|
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.address.uri = "mqtts://mqtt.eclipseprojects.io:8883",
|
||||
.verification.certificate = (const char *)mqtt_eclipse_org_pem_start,
|
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},
|
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};
|
||||
|
||||
了解其他字段的详细信息，请查看 `API 参考`_ 以及 :ref:`esp_tls_server_verification`。
|
||||
|
||||
客户端凭据
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
``credentials`` 字段下包含所有客户端相关凭据。
|
||||
|
||||
* ``username``：指向用于连接服务器用户名的指针，也可通过 URI 设置
|
||||
* ``client_id``：指向客户端 ID 的指针，默认为 ``ESP32_%CHIPID%``，其中 ``%CHIPID%`` 是十六进制 MAC 地址的最后 3 个字节
|
||||
|
||||
===============
|
||||
认证
|
||||
===============
|
||||
|
||||
可以通过 ``authentication`` 字段设置认证参数。客户端支持以下认证方式：
|
||||
|
||||
* ``authentication.password``：使用密码
|
||||
* ``authentication.certificate`` 和 ``authentication.key``：进行双向 TLS 身份验证，PEM 或 DER 格式均可
|
||||
* ``authentication.use_secure_element``：使用 ESP32-WROOM-32SE 中的安全元素
|
||||
* ``authentication.ds_data``：使用某些乐鑫设备的数字签名外设
|
||||
|
||||
会话
|
||||
^^^^^^^^^^^^
|
||||
|
||||
使用 ``section`` 字段进行 MQTT 会话相关配置。
|
||||
|
||||
========================
|
||||
遗嘱消息 (LWT)
|
||||
========================
|
||||
|
||||
通过设置 ``esp_mqtt_client_config_t.session.last_will`` 结构体的以下字段，MQTT 会在一个客户端意外断开连接时通过遗嘱消息通知其他客户端。
|
||||
|
||||
* ``topic``：指向 LWT 消息主题的指针
|
||||
* ``msg``：指向 LWT 消息的指针
|
||||
* ``msg_len``：LWT 消息的长度，``msg`` 不以空字符结尾时需要该字段
|
||||
* ``qos``：LWT 消息的服务质量
|
||||
* ``retain``：指定 LWT 消息的保留标志
|
||||
|
||||
在项目配置菜单中设置 MQTT
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
通过 ``idf.py menuconfig``，可以在 ``Component config`` > ``ESP-MQTT Configuration`` 中找到 MQTT 设置。
|
||||
|
||||
相关设置如下：
|
||||
|
||||
- :ref:`CONFIG_MQTT_PROTOCOL_311`：启用 MQTT 协议 3.1.1 版本
|
||||
|
||||
- :ref:`CONFIG_MQTT_TRANSPORT_SSL` 和 :ref:`CONFIG_MQTT_TRANSPORT_WEBSOCKET`：启用特定 MQTT 传输层，例如 SSL、WEBSOCKET 和 WEBSOCKET_SECURE
|
||||
|
||||
- :ref:`CONFIG_MQTT_CUSTOM_OUTBOX`：禁用 mqtt_outbox 默认实现，因此可以提供特定实现
|
||||
|
||||
|
||||
事件
|
||||
------------
|
||||
MQTT 客户端可能会发布以下事件：
|
||||
|
||||
* ``MQTT_EVENT_BEFORE_CONNECT``：客户端已初始化并即将开始连接至服务器。
|
||||
* ``MQTT_EVENT_CONNECTED``：客户端已成功连接至服务器。客户端已准备好收发数据。
|
||||
* ``MQTT_EVENT_DISCONNECTED``：由于无法读取或写入数据，例如因为服务器无法使用，客户端已终止连接。
|
||||
* ``MQTT_EVENT_SUBSCRIBED``：服务器已确认客户端的订阅请求。事件数据将包含订阅消息的消息 ID。
|
||||
* ``MQTT_EVENT_UNSUBSCRIBED``：服务器已确认客户端的退订请求。事件数据将包含退订消息的消息 ID。
|
||||
* ``MQTT_EVENT_PUBLISHED``：服务器已确认客户端的发布消息。消息将仅针对 QoS 级别 1 和 2 发布，因为级别 0 不会进行确认。事件数据将包含发布消息的消息 ID。
|
||||
* ``MQTT_EVENT_DATA``：客户端已收到发布消息。事件数据包含：消息 ID、发布消息所属主题名称、收到的数据及其长度。对于超出内部缓冲区的数据，将发布多个 ``MQTT_EVENT_DATA``，并更新事件数据的 ``current_data_offset`` 和 ``total_data_len`` 以跟踪碎片化消息。
|
||||
* ``MQTT_EVENT_ERROR``：客户端遇到错误。使用事件数据 ``error_handle`` 中的 ``esp_mqtt_error_type_t``，可以进一步判断错误类型。错误类型决定 ``error_handle`` 结构体的哪些部分会被填充。
|
||||
|
||||
API 参考
|
||||
-------------
|
||||
|
||||
.. include-build-file:: inc/mqtt_client.inc
|
||||
|
||||
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Reference in New Issue
Block a user