monitor.uptime-bars

def uptime_bars(checks: Sequence[Check], now: int, days: int, max_gap_seconds: int) -> List[DayBar]

BarState = Literal["operational", "degraded", "outage", "no-data"]

@dataclass(frozen=True)
class DayBar:
    """One UTC day of a status page's uptime history."""

    date: str
    #: null when nothing that day is known
    uptime_basis_points: Optional[int]
    up_seconds: int
    degraded_seconds: int
    down_seconds: int
    unknown_seconds: int
    #: outage if any down second, else degraded if any degraded, else operational; no-data when nothing is known
    state: BarState

from fune.monitor.uptime_bars import uptime_bars  # monitor.uptime-bars@^1

from typing import List, Sequence

from .monitor_check_status import Check  ← from monitor.check-status ^1.0.0 · built alongside by fune
from .monitor_uptime import uptime  ← from monitor.uptime ^1.0.0 · built alongside by fune
from .time_unix_to_iso import unix_to_iso  ← from time.unix-to-iso ^1.0.0 · built alongside by fune
from .monitor_uptime_bars_types import BarState, DayBar

_DAY = 86400


def _whole(value: object) -> bool:
    return isinstance(value, int) and not isinstance(value, bool)


def uptime_bars(checks: Sequence[Check], now: int, days: int, max_gap_seconds: int) -> List[DayBar]:
    """The last `days` UTC days ending with today, oldest first, each measured
    by monitor.uptime. Today's bar ends at `now`, so it never shows the rest
    of today as unknown."""
    if not _whole(now):
        raise ValueError("now must be whole seconds")
    if not _whole(days) or days < 1 or days > 366:
        raise ValueError("days must be 1 to 366, received %s" % (days,))
    # Floored, not truncated: before 1970 today starts on the earlier midnight.
    today_start = now - now % _DAY
    bars: List[DayBar] = []
    for i in range(days - 1, -1, -1):
        start = today_start - i * _DAY
        end = now if i == 0 else start + _DAY
        r = uptime(checks, start, end, max_gap_seconds)
        state: BarState
        if r.uptime_basis_points is None:
            state = "no-data"
        elif r.down_seconds > 0:
            state = "outage"
        elif r.degraded_seconds > 0:
            state = "degraded"
        else:
            state = "operational"
        bars.append(DayBar(
            date=unix_to_iso(start)[:10],
            uptime_basis_points=r.uptime_basis_points,
            up_seconds=r.up_seconds,
            degraded_seconds=r.degraded_seconds,
            down_seconds=r.down_seconds,
            unknown_seconds=r.unknown_seconds,
            state=state,
        ))
    return bars

Install

fune build

With that line in your source, in a Python project (language python in fune.project), fune build resolves it and its 3 dependencies, pins them in fune.lock, downloads only the Python package of each, and builds the code above into your project’s .fune/build, one readable file per capability with a header linking back here. Or pin a range in fune.project and build in one step:

fune add monitor.uptime-bars

The manifest, vectors and README with only the Python implementation. Install it without the registry with fune add ./monitor.uptime-bars-1.0.0-python.fune, or fetch it from a terminal with fune pull monitor.uptime-bars@1.0.0:python.

The whole function, every language, is one file too: monitor.uptime-bars-1.0.0.fune, 17,393 bytes, sha256 acd1ac7feb44a8df71bcace52d4de9ffefbaaa76498627388340399962540227. It installs into a project of any language.

# fune: before monitor.uptime-bars

# fune: after monitor.uptime-bars

# fune: replace monitor.check-status in monitor.uptime-bars
# fune: replace monitor.uptime in monitor.uptime-bars
# fune: replace time.unix-to-iso in monitor.uptime-bars

# fune: step monitor.uptime-bars after <n|label>

More from the author

## Days

- Days are UTC calendar days, `date` is `YYYY-MM-DD`. Status pages that show local days shift `now` first. - The last bar is today, and it ends at `now`, not midnight, so the part of today that has not happened yet is not reported as unknown. At exactly midnight today's bar is empty (`no-data`). - Midnight is found by flooring, so a `now` before 1970 still lands on the right day (`-1` is 1969-12-31). - Checks after `now` are ignored. - `days` is 1 to 366; 90 is the usual status page.

## State

In order: `no-data` when nothing that day is known; `outage` if any second was down; `degraded` if any second was degraded; otherwise `operational`. Unknown time alone does not change the colour of a day that has some known time: a monitor gap is not an outage. The worst moment decides, the way status pages colour their bars; the uptime figure says how bad the day was.

## Errors

- `now must be whole seconds` - `days must be 1 to 366, received X` - Everything `monitor.uptime` refuses: `maxGapSeconds must be a whole number of at least 1`, `checks must be in strictly ascending time order`, `unknown check status: X`.

Files