strela.templates

 1"""Templates that turn alerts into strings.
 2
 3- Currently, alerts are already barebone strings, and these templates rather "embellish"
 4  them.
 5- There are no specific tests for this module bc other tests also implicitly test the
 6  templates.
 7"""
 8
 9from typing import Optional
10from strela.symboltype import SymbolType
11from strela.alertstates import AlertState
12
13
14class AlertToTextTemplate:
15    """Template to turn alert into text string. Also serves as the base class for other
16    templates. (*Note: Should add a proper ABC for templates rather than using
17    AlertToTextTemplate (FIXME).*)
18    """
19
20    def __init__(
21        self,
22        category_name: str,
23        alert_name: str,
24        metric_name: str,
25        link_pattern: str = "",
26    ):
27        """`AlertToTextTemplate` initializer.
28
29        - `category_name`: Alert category, e.g. "Crypto".
30        - `alert_name`: Alert name, e.g. "Fluctulert".
31        - `metric_name`: Metric name, e.g. "Price".
32        - `link_pattern`: Link pattern, will be extrapolated in `apply`, e.g.
33          "https://www.google.com/search?q={symbol.name}+stock"
34
35        All the names are informational only and have no functional purpose.
36        """
37        self.category_name = category_name
38        self.alert_name = alert_name
39        self.metric_name = metric_name
40        self.link_pattern = link_pattern
41
42    def get_title(self) -> str:
43        """Return the title/subject of the alert."""
44        return f"📈🚨📉 {self.category_name} {self.metric_name} {self.alert_name}"
45
46    def apply(
47        self,
48        symbol: SymbolType,
49        alert_state: AlertState,
50        old_state: Optional[AlertState],
51        latest_value: float,
52    ) -> str:
53        """Extrapolate the template into a string and return it.
54
55        - `symbol`: Symbol for which the alert is being generated.
56        - `alert_state`: Current state of the alert.
57        - `old_state`: Previous state of the alert.
58        - `latest_value`: Latest value of the metric.
59        """
60        return f"""\
61{symbol.name} ⚠lert
62{alert_state.textify(old_state).rstrip()}
63Latest {self.metric_name}: {latest_value}
64{self.link_pattern.format(symbol=symbol)}
65"""
66
67
68class AlertToHtmlTemplate(AlertToTextTemplate):
69    """Template subclass that generates HTML."""
70
71    def apply(
72        self,
73        symbol: SymbolType,
74        alert_state: AlertState,
75        old_state: AlertState,
76        latest_value: float,
77    ) -> str:
78        return f"""\
79<a href="{self.link_pattern.format(symbol=symbol)}">{symbol.name} ⚠lert</a>
80{alert_state.htmlify(old_state).rstrip()}
81Latest {self.metric_name}: {latest_value}
82"""
83
84    def wrap_body(self, body: str) -> str:
85        """Wrap the alert in HTML wrapper tags."""
86        return f"""\
87<pre><font face="Consolas, Lucida Console, Fira Code, Courier New, Courier, monospace">
88{body}
89</font></pre>
90"""