EPrices/CHANGELOG.md

EPrices – Changelog

v1.2 — 2026-04-06

HTTP fetch stuck-flag watchdog

Fixed a reliability issue where an HTTP fetch that stalled at the TCP level (connection accepted by the server but data delivery suspended) could hold is_updating_today or is_updating_tomorrow locked at true indefinitely. While the flag was stuck, all subsequent auto-retry triggers and manual button presses were silently blocked.

Root cause: The application-level 25 s HTTP timeout does not fire when the TCP connection is established but the server stops sending data mid-transfer. The socket never goes idle from the OS perspective, so the timeout never triggers, and the fetch hangs until the TCP stack eventually resets the connection — which can take several minutes.

Fix: Added a 120-second watchdog to both the today and tomorrow worker loops (seconds: /10). If is_updating_* has been true for more than 120 seconds, the worker force-clears the flag and sets the status message to "Fetch timeout – will retry". The next scheduled retry or manual press then proceeds normally.

New globals:

• is_updating_today_since (time_t) — timestamp when is_updating_today was last set to true
• is_updating_tomorrow_since (time_t) — timestamp when is_updating_tomorrow was last set to true

Both timestamps are set immediately alongside is_updating_* = true inside smart_price_update and smart_tomorrow_price_update.

Changed locations in eprices.yaml:

• globals: — added is_updating_today_since and is_updating_tomorrow_since
• smart_price_update script — added id(is_updating_today_since) = ... alongside flag set
• smart_tomorrow_price_update script — added id(is_updating_tomorrow_since) = ... alongside flag set
• Today worker (seconds: /10) — watchdog block added before existing worker logic
• Tomorrow worker (seconds: /10) — watchdog block added before existing worker logic

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Tomorrow auto-retry attempt counter fix

Fixed a bug where tomorrow_retry_count was not incremented in the 13:55 and 14:55–19:55 hourly retry triggers. Those triggers called smart_tomorrow_price_update directly without incrementing the counter first, causing the Tomorrow API Fetch Attempts diagnostic sensor to undercount attempts after the first one at 13:25.

Changed locations in eprices.yaml:

• 13:55 trigger — added id(tomorrow_retry_count)++ before .execute()
• 14:55–19:55 hourly trigger — added id(tomorrow_retry_count)++ before .execute()

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Status message improvements

Two status message strings that contained a hardcoded time reference have been corrected. Both were misleading after a device reboot in the afternoon or a manual clear_tomorrow_prices call outside the normal fetch window.

Location	Old value	New value
tomorrow_update_status_message global initial_value	"Waiting for 13:20"	"No data yet"
clear_tomorrow_prices script end	"Cleared – awaiting next 13:20 window"	"Cleared – awaiting fetch window"

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v1.1 — 2026-04-06

Negative price provider fee support

Added a separate provider fee multiplier for negative spot prices, configurable via secrets.yaml. This correctly models contracts where the provider fee structure differs between positive and negative market prices.

New secret key:

eprices_neg_prov_fee: "0.30"

New global: neg_prov_fee (type: double)

Price calculation is now:

Market price	Formula
Positive (raw_mwh >= 0)	(raw / 1000) × (1 + prov_fee) × (1 + vat_rate)
Negative (raw_mwh < 0)	(raw / 1000) × (1 - neg_prov_fee) × (1 + vat_rate)

Key values for eprices_neg_prov_fee:

Value	Meaning
"0.30"	Provider keeps 30%, pays you 70% of negative price
"0.00"	Provider passes full negative price to you (no fee)

Switch point: raw API price (raw_mwh) before any multiplier is applied.

VAT: applied symmetrically to both positive and negative prices, consistent with net billing models where VAT is calculated on the monthly net sum (mathematically equivalent due to VAT being a linear multiplier).

Changed files: eprices.yaml, secrets.yaml

Changed locations in eprices.yaml:

• substitutions: — added neg_prov_fee_value
• globals: — added neg_prov_fee
• parse_energy_charts_today_script — MULT split into MULT_POS / MULT_NEG
• parse_energy_charts_tomorrow_script — MULT split into MULT_POS / MULT_NEG

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v1.0 — 2026-04-05

Initial release of EPrices.

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Project & device renames

Item	Value
ESPHome node name	eprices
Friendly name	EPrices
Helper file	eprices_nvs.h
C++ namespace	eprices_nvs
NVS partition namespace	eprices
Secret key prefix	eprices_

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Secrets file keys

wifi_ssid
wifi_password
eprices_fallback_ap_ssid
eprices_fallback_ap_password
eprices_api_encryption_key
eprices_timezone          # e.g. "Europe/Ljubljana"
eprices_country_bzn       # e.g. "SI"
eprices_prov_fee          # e.g. "0.12"  (provider fee as decimal multiplier)
eprices_vat_rate          # e.g. "0.22"  (VAT rate as decimal multiplier)

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Sensors

Numeric sensors (sensor:)

Name	Entity ID	Notes
Today Current Price	sensor.eprices_today_current_price
Today Next Price	sensor.eprices_today_next_price
Today Average Price	sensor.eprices_today_average_price
Today Highest Price	sensor.eprices_today_highest_price
Today Lowest Price	sensor.eprices_today_lowest_price
Today Current Hourly Price	sensor.eprices_today_current_hourly_price
Today Next Hourly Price	sensor.eprices_today_next_hourly_price
Today Highest Hourly Price	sensor.eprices_today_highest_hourly_price
Today Lowest Hourly Price	sensor.eprices_today_lowest_hourly_price
Today Current Max Hourly Price Percentage	sensor.eprices_today_current_max_hourly_price_percentage
Tomorrow Current Price	sensor.eprices_tomorrow_current_price	Evaluates at now + 86400s
Tomorrow Next Price	sensor.eprices_tomorrow_next_price	Evaluates at now + 86400s
Tomorrow Average Price	sensor.eprices_tomorrow_average_price
Tomorrow Highest Price	sensor.eprices_tomorrow_highest_price
Tomorrow Lowest Price	sensor.eprices_tomorrow_lowest_price
Tomorrow Current Hourly Price	sensor.eprices_tomorrow_current_hourly_price	Evaluates at now + 86400s
Tomorrow Next Hourly Price	sensor.eprices_tomorrow_next_hourly_price	Evaluates at now + 86400s
Tomorrow Highest Hourly Price	sensor.eprices_tomorrow_highest_hourly_price
Tomorrow Lowest Hourly Price	sensor.eprices_tomorrow_lowest_hourly_price
Tomorrow Current Max Hourly Price Percentage	sensor.eprices_tomorrow_current_max_hourly_price_percentage	Evaluates at now + 86400s
WiFi Signal	sensor.eprices_wifi_signal	dBm, diagnostic
Uptime	sensor.eprices_uptime	Human-readable string, diagnostic

Text sensors (text_sensor:)

Name	Entity ID	Notes
Today JSON Hourly Prices EUR⁄kWh	sensor.eprices_today_json_hourly_prices_eur_kwh	JSON array, 24 values
Today JSON 15-Min Prices EUR⁄kWh (P1 00:00-07:45)	sensor.eprices_today_json_15_min_prices_eur_kwh_p1_00_00_07_45	JSON array, 32 values
Today JSON 15-Min Prices EUR⁄kWh (P2 08:00-15:45)	sensor.eprices_today_json_15_min_prices_eur_kwh_p2_08_00_15_45	JSON array, 32 values
Today JSON 15-Min Prices EUR⁄kWh (P3 16:00-23:45)	sensor.eprices_today_json_15_min_prices_eur_kwh_p3_16_00_23_45	JSON array, 32 values
Today Highest Price Time	sensor.eprices_today_highest_price_time	HH:MM
Today Lowest Price Time	sensor.eprices_today_lowest_price_time	HH:MM
Today Highest Hourly Price Time	sensor.eprices_today_highest_hourly_price_time	HH:00
Today Lowest Hourly Price Time	sensor.eprices_today_lowest_hourly_price_time	HH:00
Today Current Price Status	sensor.eprices_today_current_price_status	Valid / Missing / Stale
Today Data Loaded Time	sensor.eprices_today_data_loaded_time	Stamped on NVS load and HTTP fetch
Today Last API Fetch Time	sensor.eprices_today_last_api_fetch_time	Stamped on HTTP fetch only; Never if NVS only; diagnostic
Today Price Update Status	sensor.eprices_today_price_update_status	SUCCESS / FAILED/WAITING; diagnostic
Today Price Update Status Message	sensor.eprices_today_price_update_status_message	Detailed status string; diagnostic
Today API Fetch Attempts	sensor.eprices_today_api_fetch_attempts	HTTP fetch count; resets at midnight; diagnostic
Today Entry Count	sensor.eprices_today_entry_count	Number of stored price points; diagnostic
Tomorrow JSON Hourly Prices EUR⁄kWh	sensor.eprices_tomorrow_json_hourly_prices_eur_kwh	JSON array, 24 values
Tomorrow JSON 15-Min Prices EUR⁄kWh (P1 00:00-07:45)	sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p1_00_00_07_45	JSON array, 32 values
Tomorrow JSON 15-Min Prices EUR⁄kWh (P2 08:00-15:45)	sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p2_08_00_15_45	JSON array, 32 values
Tomorrow JSON 15-Min Prices EUR⁄kWh (P3 16:00-23:45)	sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p3_16_00_23_45	JSON array, 32 values
Tomorrow Highest Price Time	sensor.eprices_tomorrow_highest_price_time	HH:MM
Tomorrow Lowest Price Time	sensor.eprices_tomorrow_lowest_price_time	HH:MM
Tomorrow Highest Hourly Price Time	sensor.eprices_tomorrow_highest_hourly_price_time	HH:00
Tomorrow Lowest Hourly Price Time	sensor.eprices_tomorrow_lowest_hourly_price_time	HH:00
Tomorrow Current Price Status	sensor.eprices_tomorrow_current_price_status	Valid / Missing / Waiting...
Tomorrow Data Loaded Time	sensor.eprices_tomorrow_data_loaded_time	Stamped on NVS load and HTTP fetch; Outside fetch window before 13:20
Tomorrow Last API Fetch Time	sensor.eprices_tomorrow_last_api_fetch_time	Stamped on HTTP fetch only; Never if NVS only; diagnostic
Tomorrow Price Update Status	sensor.eprices_tomorrow_price_update_status	SUCCESS / FAILED/WAITING; diagnostic
Tomorrow Price Update Status Message	sensor.eprices_tomorrow_price_update_status_message	Detailed status string; diagnostic
Tomorrow API Fetch Attempts	sensor.eprices_tomorrow_api_fetch_attempts	HTTP fetch count; resets at 13:25; diagnostic
Tomorrow Entry Count	sensor.eprices_tomorrow_entry_count	Number of stored price points; diagnostic
Last Reboot	sensor.eprices_last_reboot	Boot timestamp; diagnostic
Last Update Source	sensor.eprices_last_update_source	NVS_boot / HTTP_today / midnight_bridge etc.; diagnostic
Today NVS Status	sensor.eprices_today_nvs_status	NVS load/store result; diagnostic
Tomorrow NVS Status	sensor.eprices_tomorrow_nvs_status	NVS load/store result; diagnostic
Today Data Date	sensor.eprices_today_data_date	Date of stored today data; diagnostic
Tomorrow Data Date	sensor.eprices_tomorrow_data_date	Date of stored tomorrow data; diagnostic

Buttons

Name	Entity ID
Force Today's Update	button.eprices_force_today_s_update
Force Tomorrow's Update	button.eprices_force_tomorrow_s_update
Reboot Device	button.eprices_reboot_device

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Key behaviours

• Price calculation: price_eur_kwh = (raw_eur_mwh / 1000) × (1 + prov_fee) × (1 + vat_rate)
• Negative prices: formatted as %.3f (3 decimal places) to stay within the 255-character HA text sensor state limit; positive prices use %.4f
• DST-safe: all price indexing uses UNIX timestamps and binary search — no hour-slot arithmetic
• NVS persistence: prices survive reboots; stale data (date mismatch) is discarded and triggers a fresh HTTP fetch
• Today Current Price Status shows Stale if stored date does not match today's date
• Tomorrow live sensors evaluate at now + 86400s so they reflect tomorrow at the same local time
• Tomorrow Data Loaded Time shows Outside fetch window when device boots before 13:20
• API fetch times reset to Never at midnight bridge and on clear_tomorrow_prices
• API fetch attempt counters reset to 0 at midnight and publish 0 immediately on boot
• Uptime displayed as human-readable string: 45 s / 5 min / 3 h 22 min / 12 d 4 h / 4 months 12 d