Support use via bean-price.

README.md

@@ -249,6 +249,62 @@ pricehist fetch coindesk BTC/USD -s 2021-01-01 -e 2021-01-05 -vvv 2>&1 \
 }
 ```
 
+### Use via `bean-price`
+
+Beancount users may wish to use `pricehist` sources via `bean-price`. To do so,
+ensure the `pricehist` package is installed in an accessible location.
+
+You can fetch the latest price directly from the command line.
+
+```
+bean-price -e "USD:pricehist.beanprice.coindesk/BTC:USD"
+```
+```
+2021-08-18 price BTC:USD                          44725.12 USD
+```
+
+You can fetch a series of prices by providing a Beancount file as input.
+
+```
+; input.beancount
+2021-08-14 commodity BTC
+  price: "USD:pricehist.beanprice.coindesk/BTC:USD:close"
+```
+
+```
+bean-price input.beancount --update --update-rate daily --inactive --clear-cache
+```
+```
+2021-08-14 price BTC                            47098.2633 USD
+2021-08-15 price BTC                            47018.9017 USD
+2021-08-16 price BTC                             45927.405 USD
+2021-08-17 price BTC                            44686.3333 USD
+2021-08-18 price BTC                              44725.12 USD
+```
+
+Adding `-v` will print progress information, `-vv` will print debug information,
+including that from `pricehist`.
+
+A source map specification for `bean-price` has the form
+`<currency>:<module>/[^]<ticker>`. Additional `<module>/[^]<ticker>` parts can
+be appended, separated by commas.
+
+The module name will be of the form `pricehist.beanprice.<source_id>`.
+
+The ticker symbol will be of the form `BASE:QUOTE:TYPE`.
+
+Any non-alphanumeric characters except the equals sign (`=`), hyphen (`-`),
+period (`.`), or parentheses (`(` or `)`) are special characters that need to
+be encoded as their a two-digit hexadecimal code prefixed with an underscore,
+because `bean-price` ticker symbols don't allow all the characters used by
+`pricehist` pairs.
+[This page](https://replit.com/@chrisberkhout/bpticker) will do it for you.
+
+For example, the Yahoo! Finance symbol for the Dow Jones Industrial Average is
+`^DJI`, and would have the source map specification
+`USD:pricehist.beanprice.yahoo/_5eDJI`, or for the daily high price
+`USD:pricehist.beanprice.yahoo/_5eDJI::high`.
+
 ### Use as a library
 
 You may find `pricehist`'s source classes useful in your own scripts.

src/pricehist/beanprice/__init__.py

@@ -0,0 +1,77 @@
+import re
+from datetime import date, datetime, timedelta, timezone
+from decimal import Decimal
+from typing import List, NamedTuple, Optional
+
+from pricehist import exceptions
+from pricehist.series import Series
+
+SourcePrice = NamedTuple(
+    "SourcePrice",
+    [
+        ("price", Decimal),
+        ("time", Optional[datetime]),
+        ("quote_currency", Optional[str]),
+    ],
+)
+
+
+def source(pricehist_source):
+    class Source:
+        def get_latest_price(self, ticker: str) -> Optional[SourcePrice]:
+            time_end = datetime.combine(date.today(), datetime.min.time())
+            time_begin = time_end - timedelta(days=7)
+            prices = self.get_prices_series(ticker, time_begin, time_end)
+            if prices:
+                return prices[-1]
+            else:
+                return None
+
+        def get_historical_price(
+            self, ticker: str, time: datetime
+        ) -> Optional[SourcePrice]:
+            prices = self.get_prices_series(ticker, time, time)
+            if prices:
+                return prices[-1]
+            else:
+                return None
+
+        def get_prices_series(
+            self,
+            ticker: str,
+            time_begin: datetime,
+            time_end: datetime,
+        ) -> Optional[List[SourcePrice]]:
+            base, quote, type = self._decode(ticker)
+
+            start = time_begin.date().isoformat()
+            end = time_end.date().isoformat()
+
+            local_tz = datetime.now(timezone.utc).astimezone().tzinfo
+            user_tz = time_begin.tzinfo or local_tz
+
+            try:
+                series = pricehist_source.fetch(Series(base, quote, type, start, end))
+            except exceptions.SourceError:
+                return None
+
+            return [
+                SourcePrice(
+                    price.amount,
+                    datetime.fromisoformat(price.date).replace(tzinfo=user_tz),
+                    series.quote,
+                )
+                for price in series.prices
+            ]
+
+        def _decode(self, ticker):
+            # https://github.com/beancount/beanprice/blob/b05203/beanprice/price.py#L166
+            parts = [
+                re.sub(r"_[0-9a-fA-F]{2}", lambda m: chr(int(m.group(0)[1:], 16)), part)
+                for part in ticker.split(":")
+            ]
+            base, quote, candidate_type = (parts + [""] * 3)[0:3]
+            type = candidate_type or pricehist_source.types()[0]
+            return (base, quote, type)
+
+    return Source

src/pricehist/beanprice/alphavantage.py

@@ -0,0 +1,4 @@
+from pricehist import beanprice
+from pricehist.sources.alphavantage import AlphaVantage
+
+Source = beanprice.source(AlphaVantage())

src/pricehist/beanprice/coindesk.py

@@ -0,0 +1,4 @@
+from pricehist import beanprice
+from pricehist.sources.coindesk import CoinDesk
+
+Source = beanprice.source(CoinDesk())

src/pricehist/beanprice/coinmarketcap.py

@@ -0,0 +1,4 @@
+from pricehist import beanprice
+from pricehist.sources.coinmarketcap import CoinMarketCap
+
+Source = beanprice.source(CoinMarketCap())

src/pricehist/beanprice/ecb.py

@@ -0,0 +1,4 @@
+from pricehist import beanprice
+from pricehist.sources.ecb import ECB
+
+Source = beanprice.source(ECB())

src/pricehist/beanprice/yahoo.py

@@ -0,0 +1,4 @@
+from pricehist import beanprice
+from pricehist.sources.yahoo import Yahoo
+
+Source = beanprice.source(Yahoo())

tests/pricehist/test_beanprice.py

@@ -0,0 +1,141 @@
+import importlib
+from datetime import date, datetime, timedelta, timezone
+from decimal import Decimal
+
+import pytest
+
+from pricehist import beanprice, exceptions, sources
+from pricehist.price import Price
+from pricehist.series import Series
+
+
+@pytest.fixture
+def series():
+    series = Series(
+        "BTC",
+        "USD",
+        "high",
+        "2021-01-01",
+        "2021-01-03",
+        prices=[
+            Price("2021-01-01", Decimal("1.1")),
+            Price("2021-01-02", Decimal("1.2")),
+            Price("2021-01-03", Decimal("1.3")),
+        ],
+    )
+    return series
+
+
+@pytest.fixture
+def pricehist_source(mocker, series):
+    mock = mocker.MagicMock()
+    mock.types = mocker.MagicMock(return_value=["close", "high", "low"])
+    mock.fetch = mocker.MagicMock(return_value=series)
+    return mock
+
+
+@pytest.fixture
+def source(pricehist_source):
+    return beanprice.source(pricehist_source)()
+
+
+@pytest.fixture
+def ltz():
+    return datetime.now(timezone.utc).astimezone().tzinfo
+
+
+def test_get_prices_series(pricehist_source, source, ltz):
+    ticker = "BTC:USD:high"
+    begin = datetime(2021, 1, 1, tzinfo=ltz)
+    end = datetime(2021, 1, 3, tzinfo=ltz)
+    result = source.get_prices_series(ticker, begin, end)
+
+    pricehist_source.fetch.assert_called_once_with(
+        Series("BTC", "USD", "high", "2021-01-01", "2021-01-03")
+    )
+
+    assert result == [
+        beanprice.SourcePrice(Decimal("1.1"), datetime(2021, 1, 1, tzinfo=ltz), "USD"),
+        beanprice.SourcePrice(Decimal("1.2"), datetime(2021, 1, 2, tzinfo=ltz), "USD"),
+        beanprice.SourcePrice(Decimal("1.3"), datetime(2021, 1, 3, tzinfo=ltz), "USD"),
+    ]
+
+
+def test_get_prices_series_exception(pricehist_source, source, ltz, mocker):
+    pricehist_source.fetch = mocker.MagicMock(
+        side_effect=exceptions.RequestError("Message")
+    )
+    ticker = "_5eDJI::low"
+    begin = datetime(2021, 1, 1, tzinfo=ltz)
+    end = datetime(2021, 1, 3, tzinfo=ltz)
+    result = source.get_prices_series(ticker, begin, end)
+    assert result is None
+
+
+def test_get_prices_series_special_chars(pricehist_source, source, ltz):
+    ticker = "_5eDJI::low"
+    begin = datetime(2021, 1, 1, tzinfo=ltz)
+    end = datetime(2021, 1, 3, tzinfo=ltz)
+    source.get_prices_series(ticker, begin, end)
+    pricehist_source.fetch.assert_called_once_with(
+        Series("^DJI", "", "low", "2021-01-01", "2021-01-03")
+    )
+
+
+def test_get_prices_series_price_type(pricehist_source, source, ltz):
+    ticker = "TSLA"
+    begin = datetime(2021, 1, 1, tzinfo=ltz)
+    end = datetime(2021, 1, 3, tzinfo=ltz)
+    source.get_prices_series(ticker, begin, end)
+    pricehist_source.fetch.assert_called_once_with(
+        Series("TSLA", "", "close", "2021-01-01", "2021-01-03")
+    )
+
+
+def test_get_historical_price(pricehist_source, source, ltz):
+    ticker = "BTC:USD:high"
+    time = datetime(2021, 1, 3, tzinfo=ltz)
+    result = source.get_historical_price(ticker, time)
+    pricehist_source.fetch.assert_called_once_with(
+        Series("BTC", "USD", "high", "2021-01-03", "2021-01-03")
+    )
+    assert result == beanprice.SourcePrice(
+        Decimal("1.3"), datetime(2021, 1, 3, tzinfo=ltz), "USD"
+    )
+
+
+def test_get_historical_price_none_available(pricehist_source, source, ltz, mocker):
+    pricehist_source.fetch = mocker.MagicMock(
+        return_value=Series("BTC", "USD", "high", "2021-01-03", "2021-01-03", prices=[])
+    )
+    ticker = "BTC:USD:high"
+    time = datetime(2021, 1, 3, tzinfo=ltz)
+    result = source.get_historical_price(ticker, time)
+    assert result is None
+
+
+def test_get_latest_price(pricehist_source, source, ltz):
+    ticker = "BTC:USD:high"
+    start = datetime.combine((date.today() - timedelta(days=7)), datetime.min.time())
+    today = datetime.combine(date.today(), datetime.min.time())
+    result = source.get_latest_price(ticker)
+    pricehist_source.fetch.assert_called_once_with(
+        Series("BTC", "USD", "high", start.date().isoformat(), today.date().isoformat())
+    )
+    assert result == beanprice.SourcePrice(
+        Decimal("1.3"), datetime(2021, 1, 3, tzinfo=ltz), "USD"
+    )
+
+
+def test_get_latest_price_none_available(pricehist_source, source, ltz, mocker):
+    pricehist_source.fetch = mocker.MagicMock(
+        return_value=Series("BTC", "USD", "high", "2021-01-01", "2021-01-03", prices=[])
+    )
+    ticker = "BTC:USD:high"
+    result = source.get_latest_price(ticker)
+    assert result is None
+
+
+def test_all_sources_available_for_beanprice():
+    for identifier in sources.by_id.keys():
+        importlib.import_module(f"pricehist.beanprice.{identifier}").Source()