1st POC

2026-08-30 11:01:19 +02:00
parent a34cf42f0e
commit fcae3569fc
17 changed files with 679 additions and 1 deletions
@@ -0,0 +1,111 @@
+from __future__ import annotations
+
+import colorsys
+import re
+import tempfile
+from pathlib import Path
+
+import rrdtool
+
+from .data import Sample
+
+RRD_ERROR = rrdtool.OperationalError
+
+STEP = 600
+HEARTBEAT = 1500
+SAFE_NAME = re.compile(r"^[a-z][a-z0-9_]*$")
+
+SCHEMAS = {
+    "outdoor": {"min_temp": "GAUGE:-60:70", "max_temp": "GAUGE:-60:70", "humidity": "GAUGE:0:100", "pressure": "GAUGE:800:1200"},
+    "wind": {"gust": "GAUGE:0:300", "average": "GAUGE:0:300", "angle": "GAUGE:0:360"},
+    "bedroom": {"temperature": "GAUGE:-20:60", "co2": "GAUGE:0:10000", "humidity": "GAUGE:0:100"},
+    "study": {"temperature": "GAUGE:-20:60", "co2": "GAUGE:0:10000", "humidity": "GAUGE:0:100"},
+    "living": {"temperature": "GAUGE:-20:60", "co2": "GAUGE:0:10000", "humidity": "GAUGE:0:100"},
+}
+
+PERIODS = {"day": ("1 day", "-1d"), "2weeks": ("2 weeks", "-14d"), "year": ("1 year", "-1y")}
+ALIASES = {"1day": "day", "14days": "2weeks", "2week": "2weeks", "1year": "year"}
+
+
+class RRDStore:
+    def __init__(self, folder: Path, width: int = 900, height: int = 240):
+        self.folder = Path(folder)
+        self.width = width
+        self.height = height
+
+    def path(self, name: str) -> Path:
+        if name not in SCHEMAS:
+            raise KeyError(name)
+        return self.folder / f"{name}.rrd"
+
+    def ensure_all(self) -> None:
+        self.folder.mkdir(parents=True, exist_ok=True)
+        for name, schema in SCHEMAS.items():
+            path = self.path(name)
+            if path.exists():
+                continue
+            # Leave room for a station that has been temporarily offline when the
+            # RRD is first created; RRDtool rejects samples older than --start.
+            args = ["--step", str(STEP), "--start", "now-1d"]
+            args += [f"DS:{field}:{definition.split(':', 1)[0]}:{HEARTBEAT}:{definition.split(':', 1)[1]}" for field, definition in schema.items()]
+            # 10-minute points for 2 weeks; 6-hour averages for over a year.
+            args += ["RRA:AVERAGE:0.5:1:2016", "RRA:MIN:0.5:1:2016", "RRA:MAX:0.5:1:2016",
+                     "RRA:AVERAGE:0.5:36:1464", "RRA:MIN:0.5:36:1464", "RRA:MAX:0.5:36:1464"]
+            rrdtool.create(str(path), *args)
+
+    def update(self, name: str, sample: Sample) -> None:
+        schema = SCHEMAS[name]
+        fields = list(schema)
+        values = ["U" if sample.values.get(field) is None else str(sample.values[field]) for field in fields]
+        rrdtool.update(
+            str(self.path(name)),
+            "--template", ":".join(fields),
+            f"{sample.timestamp}:{':'.join(values)}",
+        )
+
+    def last(self, name: str, field: str) -> dict:
+        if name not in SCHEMAS or field not in SCHEMAS[name]:
+            raise KeyError(f"{name}/{field}")
+        latest = rrdtool.lastupdate(str(self.path(name)))
+        value = latest["ds"][field]
+        return {
+            "rrd": name,
+            "data_point": field,
+            "timestamp": int(latest["date"].timestamp()),
+            "value": None if value is None else float(value),
+        }
+
+    def graph(self, name: str, period: str) -> bytes:
+        period = ALIASES.get(period, period)
+        if name not in SCHEMAS or period not in PERIODS:
+            raise KeyError(f"{name}/{period}")
+        title, start = PERIODS[period]
+        common = ["--imgformat", "PNG", "--start", start, "--end", "now",
+                  "--width", str(self.width), "--height", str(self.height), "--title", f"{name.title()} - {title}",
+                  "--slope-mode", "--watermark", "GetNetatmoData v2"]
+        definitions = [f"DEF:{field}={self.path(name)}:{field}:AVERAGE" for field in SCHEMAS[name]]
+        if name == "wind":
+            drawings = self._wind_drawings()
+        elif name == "outdoor":
+            drawings = ["LINE2:min_temp#3488DB:Minimum temperature (C)", "LINE2:max_temp#E74C3C:Maximum temperature (C)",
+                        "LINE1:humidity#27AE60:Humidity (%)", "LINE1:pressure#8E44AD:Pressure (hPa):dashes"]
+        else:
+            drawings = ["LINE2:temperature#E74C3C:Temperature (C)", "LINE1:co2#8E44AD:CO2 (ppm)", "LINE1:humidity#27AE60:Humidity (%):dashes"]
+        # The Python binding returns graph metadata, not the encoded image, so
+        # render to an isolated temporary file and return its contents.
+        with tempfile.TemporaryDirectory(prefix="netatmo-graph-") as folder:
+            image_path = Path(folder) / f"{name}-{period}.png"
+            rrdtool.graph(str(image_path), *(common + definitions + drawings))
+            return image_path.read_bytes()
+
+    @staticmethod
+    def _wind_drawings() -> list[str]:
+        result: list[str] = []
+        # Split average wind into 12 angle bands. Each AREA starts at zero and
+        # only exists for its direction, producing rainbow-colored bars/areas.
+        for index in range(12):
+            low, high = index * 30, (index + 1) * 30
+            color = "#%02X%02X%02X80" % tuple(round(channel * 255) for channel in colorsys.hsv_to_rgb(index / 12, .85, .9))
+            result += [f"CDEF:dir{index}=angle,{low},GE,angle,{high},LT,*,average,UNKN,IF", f"AREA:dir{index}{color}:{low:03d}-{high:03d} degrees"]
+        result += ["LINE2:gust#111111:Gust", "LINE1:average#555555:Average"]
+        return result