The wait between attempts started at 1 s again when the broker accepted the
session, so a session that was closed right after it opened (two boards with
one client id) came back every 2 s without end. It now starts again only
after a session that lasted 60 s; across shorter ones it keeps doubling.
An attempt given up after 30 s prints "the broker did not answer within
30 s", and loss of Wi-Fi prints "Wi-Fi is down, waiting for it" once per loss.
setServer(host, port) before begin() names another broker; the host is not
copied. basicLight: static RAM 30,616 B (+16), flash 333,701 B (+264);
91 host tests (bridge logic 50).
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
The root topic identifies the account, and Serial logs get posted in issues and forums.
"repeated directive on <topic> ignored" and the lines for dropped directives printed the full
MQTT topic; they now start with the endpoint id. The lines for subscriptions and publishes print
the topic relative to the root (AlexaBridgeLogic::topicForLog), and begin() prints the length of
the root topic instead of its text. No line at any level prints the root topic, the username or
the password.
basicLight: RAM 34,476 -> 34,508 B, flash 338,281 -> 338,533 B; host tests 45 -> 47.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
The session is opened again whatever AsyncMqttClient gives as the reason, after 1 s doubling
to 60 s (AlexaReconnectBackoff, reset when a session opens), and only while Wi-Fi is up.
1.1.0 retried a lost TCP connection every 5 s and nothing else, silently: a refused password
or a broker that was restarting left the board offline until a reset.
Every disconnect prints its reason in words and the wait before the next attempt. The first
connect waits for Wi-Fi; a connect without an answer after 30 s counts as failed, because the
MQTT client reports nothing when no TCP connection was made. Keep-alive 30 s.
basicLight: RAM 34,452 -> 34,476 B, flash 337,461 -> 338,281 B; host tests 41 -> 45.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
8ea7778 kept one directive for loop() and recognised the repeat that the broker mirror delivers in two ways: bytes compared with the directive that still waited, and the messageId once loop() had parsed it. A repeat that arrived after its directive had been read therefore took the one place until the next loop(), and a different directive behind it was dropped. Alexa sends a group command as one directive per endpoint, so a board with several endpoints lost directives whenever they arrived faster than loop() ran; 1.1.0 queued five tokens.
AlexaDirectiveBuffer is now a queue. The arriving message is collected in a heap block of its own and hashed (FNV-1a, 64 bit) as its fragments come in. At the last fragment it is one of three things: a repeat, when the hash is among the last 16 that were queued, and then it is freed and never takes a place; a directive, which is queued; or lost, when eight directives (ALEX2ESP_MAX_QUEUED_DIRECTIVES) or 8188 bytes (ALEX2ESP_MAX_QUEUED_BYTES, four times the largest directive) already wait. Whether there is a place is decided at the last fragment, because loop() may have read a directive by then. A message for which there is no memory is still hashed, so its loss is reported only when it is not a repeat. loop() parses one directive per call, in the order of arrival, and frees its block before the handler runs.
The messageId check stays for a directive that comes again with other bytes; it remembers 16 ids instead of 4 and shares the ring with the buffer (AlexaRecentHashes). The two limits are in src/AlexaLimits.h, with #error for values that cannot work. The constructor of the buffer takes the allocator, malloc by default, so the tests can let it fail.
For a sketch: nothing to change. The error line of a directive that finds no place reads "directive of N bytes on <topic> dropped: 8 directives, M bytes, already wait for loop()". The heap holds up to 8188 bytes of waiting directives and one arriving directive of up to 2048, where it held one directive.
Measured with the bridge built for the host against a fake MQTT client (not in the repository), directives of 793 bytes, every message delivered twice, 8ea7778 -> this commit:
repeat of D1 and a new D2 after D1 was handled D2 dropped -> D2 handled
group of 5 in one burst 1 of 5 handled, 8 error lines -> 5 of 5, none
group of 8 in one burst 8 of 8 handled, no error line
group of 10 in one burst, not mirrored 8 of 10 handled, 2 error lines
group of 10, a loop() after every fourth message 10 of 10 handled, no error line
Tests: 41 host tests (33 before). New: the order of the queue and the reuse of its places, the ninth directive, a place that becomes free while a directive arrives, the limit in bytes, the largest directive in an empty queue, the repeat of a waiting directive and of one that was read, a group of five with repeats, a repeat when no place is free, a directive that differs in one byte, how long a repeat is remembered, a directive and a repeat without memory, the FNV-1a test vectors. They also pass under -fsanitize=address,undefined. Seven faults planted in a copy of AlexaBridgeLogic.cpp (no repeat check, no limit in bytes, no limit in places, no bounds check, a lost directive remembered, release() that keeps the bytes, last in first out) were each noticed: six by failing tests, the missing bounds check by AddressSanitizer as a heap-buffer-overflow.
Built for d1_mini with empty credentials (PlatformIO 6.2.0, espressif8266 4.2.1), static RAM / flash in bytes, e48f858 -> this commit, no warnings:
basicLight 34,116 / 336,757 -> 34,444 / 337,145
lightWithBrightness 34,232 / 340,517 -> 34,560 / 340,921
lightWithColorTemp 34,380 / 341,177 -> 34,708 / 341,581
tempSensor 34,024 / 335,457 -> 34,352 / 335,845
blindControl 34,256 / 338,925 -> 34,584 / 339,313
The 328 bytes of RAM are the two rings of 16 hashes (256) and the eight places of the queue.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Both limits were 2047 bytes. An answer repeats the correlationToken of its directive, which is most of a large directive, and adds 140 to 170 bytes for every property. So a directive between about 1,750 and 2,047 bytes was accepted, the sketch acted on it, and the answer was refused: the lamp switched and Alexa reported a device that does not respond.
The limit for messages now follows the limit for directives unless it is set: 2047 + 1024 = 3071 bytes, room for six properties on top of the largest directive. Both defines moved to src/AlexaLimits.h, next to each other, with the relation in the comment. The limit also applies to the discovery object of a device, which may now be 3071 bytes.
For a sketch: a report between 2,048 and 3,071 bytes is sent, where it was refused with an error. A project that sets ALEX2ESP_MAX_MESSAGE keeps its value.
Measured with the bridge built for the host against a fake MQTT client (not in the repository), a TurnOn of 2,047 bytes answered with two properties:
8ea7778 handler ran, send() false, "2374 bytes not sent, the limit is 2047"
this commit handler ran, send() true, 2,374 bytes published
Tests: test_largest_directive_can_be_answered puts a directive of ALEX2ESP_MAX_DIRECTIVE bytes through the receive buffer, builds the Response of a lamp to it and checks it against ALEX2ESP_MAX_MESSAGE, also with six properties. 33 host tests pass.
examples/basicLight.cpp for d1_mini, static RAM / flash in bytes: 34,116 / 336,757 -> 34,116 / 336,757, no warnings.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
The library fetched every directive over HTTP (GET /Alex2ESP/<token>, the token taken from <root>/<id>/alexaDirective_e) and posted every report back over HTTP. The detour was built in 2024 because AsyncMqttClient hands a message larger than one TCP segment to onMessage in fragments. Alex2MQTT publishes the whole directive on <root>/<id>/alexaDirective, so the fragments are reassembled instead: by index/total, into one heap block of total + 1 bytes that is freed as soon as loop() has parsed it.
Removed: ESP8266HTTPClient with processHttpGet/processHttpPost and their two HTTPClient and two WiFiClient members; the 5-slot packet, topic and receive queues, combinedData, receivePayload and AlexaStatusMessage::outputString (17,264 bytes of .bss); the {MESSAGE_PAYLOAD_SPLIT} and {REPLACE_WITH_DATETIME} conventions; the subscription to the _e token topic; AlexaUtils.cpp (AlexaUtils::printMemoryInfo stays, in the header).
Receive: the bridge subscribes <root>/discover and <root>/+/alexaDirective. The MQTT callback only collects; loop() parses and dispatches, and answers discovery. A directive over ALEX2ESP_MAX_DIRECTIVE (2047) is refused. One directive is in flight: a second one that arrives before loop() ran is dropped. Both are logged. A byte-identical repeat of the waiting directive and a repeat of one of the last four messageIds (kept as 64-bit hashes, 32 bytes) are ignored, because the broker mirror delivers every message twice. The wildcard subscription also delivers the directives of other boards of the account; they are recognised by their topic before anything is allocated.
Publish: measureJson first. A message is refused when it is over ALEX2ESP_MAX_MESSAGE (2047), when its document overflowed, when there is no session, when the packet does not fit the largest free block, or when AsyncMqttClient returns 0. Every refusal is logged and returned as an AlexaSendResult; AlexaStatusMessage::send() keeps its bool. The limit now also applies to the discovery object of a device.
Time: timeOfSample is an ISO 8601 UTC instant from the clock of the board (gmtime_r + snprintf, no strftime). begin() calls configTime(0, 0, "pool.ntp.org", "time.nist.gov") and loop() holds the first connect until the clock is set or 5 s have passed. setTimeSource(false) leaves the clock to the sketch. AddContextProp() fills timeOfSample in when a hand-built property has none or carries the old placeholder.
Log: AlexaLog, with a level at run time (setLogLevel) and a ceiling at build time (ALEX2ESP_LOG_MAX), replaces the Serial prints and the Alex2ESP_DEBUG define; the new receive and publish paths need a line for every refusal. The log and the time stamp call vsnprintf/snprintf with a PROGMEM format and not the _P variants: newlib keeps those in one object with printf_P and sprintf_P, which links the FILE-based printf. Measured on basicLight: 5,776 bytes of flash.
For a sketch: the 1.x API is unchanged, the five examples compile unmodified and without warnings. loop() no longer blocks for two HTTP round trips per directive. send() publishes at once and returns false without a session, where 1.1.0 queued the report. The MQTT session opens from loop(), up to 5 s after begin(). getState() is CONNECTED once both subscriptions are acknowledged. The 1.2.0 section of readme.md lists every change; its transport section is rewritten.
Measured for d1_mini with empty credentials (PlatformIO 6.2.0, espressif8266 4.2.1, Arduino core 3.1.2), static RAM / flash in bytes, 1.1.0 -> this commit:
basicLight 52,768 / 350,885 -> 34,116 / 336,757
lightWithBrightness 52,880 / 354,729 -> 34,232 / 340,517
lightWithColorTemp 53,028 / 355,389 -> 34,380 / 341,177
tempSensor 52,676 / 349,441 -> 34,024 / 335,457
blindControl 52,900 / 353,069 -> 34,256 / 338,925
basicLight with -DALEX2ESP_LOG_MAX=0: 34,108 / 333,289. SNTP and the time stamp are 1,848 bytes of the flash figure.
Tests: platformio.ini with [env:native] and test/test_bridge_logic, 32 host tests of the logic in src/AlexaBridgeLogic.cpp (reassembly at every fragment size, both limits, repeats, publish checks, topics, time stamps). They also pass under -fsanitize=address,undefined. .gitignore no longer hides /test.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
