refactor: make pricing.py the single source of truth for pricing

cli.py

@@ -16,46 +16,8 @@
 
 DB_PATH = Path.home() / ".claude" / "usage.db"
 
-PRICING = {
-    "claude-opus-4-7":   {"input": 5.00, "output": 25.00, "cache_read": 0.50, "cache_write": 6.25},
-    "claude-opus-4-6":   {"input": 5.00, "output": 25.00, "cache_read": 0.50, "cache_write": 6.25},
-    "claude-opus-4-5":   {"input": 5.00, "output": 25.00, "cache_read": 0.50, "cache_write": 6.25},
-    "claude-sonnet-4-7": {"input": 3.00, "output": 15.00, "cache_read": 0.30, "cache_write": 3.75},
-    "claude-sonnet-4-6": {"input": 3.00, "output": 15.00, "cache_read": 0.30, "cache_write": 3.75},
-    "claude-sonnet-4-5": {"input": 3.00, "output": 15.00, "cache_read": 0.30, "cache_write": 3.75},
-    "claude-haiku-4-7":  {"input": 1.00, "output":  5.00, "cache_read": 0.10, "cache_write": 1.25},
-    "claude-haiku-4-6":  {"input": 1.00, "output":  5.00, "cache_read": 0.10, "cache_write": 1.25},
-    "claude-haiku-4-5":  {"input": 1.00, "output":  5.00, "cache_read": 0.10, "cache_write": 1.25},
-}
-
-def get_pricing(model):
-    if not model:
-        return None
-    if model in PRICING:
-        return PRICING[model]
-    for key in PRICING:
-        if model.startswith(key):
-            return PRICING[key]
-    # Substring fallback: match model family by keyword
-    m = model.lower()
-    if "opus" in m:
-        return PRICING["claude-opus-4-7"]
-    if "sonnet" in m:
-        return PRICING["claude-sonnet-4-6"]
-    if "haiku" in m:
-        return PRICING["claude-haiku-4-5"]
-    return None
+from pricing import PRICING, get_pricing, calc_cost
 
-def calc_cost(model, inp, out, cache_read, cache_creation):
-    p = get_pricing(model)
-    if not p:
-        return 0.0
-    return (
-        inp            * p["input"]       / 1_000_000 +
-        out            * p["output"]      / 1_000_000 +
-        cache_read     * p["cache_read"]  / 1_000_000 +
-        cache_creation * p["cache_write"] / 1_000_000
-    )
 
 def fmt(n):
     if n >= 1_000_000:

dashboard.py

@@ -7,6 +7,8 @@
 import sqlite3
 from http.server import HTTPServer, BaseHTTPRequestHandler
 from pathlib import Path
+
+from pricing import PRICING
 from datetime import datetime
 
 DB_PATH = Path.home() / ".claude" / "usage.db"
@@ -418,17 +420,7 @@ def get_dashboard_data(db_path=DB_PATH):
 }
 
 // ── Pricing (Anthropic API, April 2026) ────────────────────────────────────
-const PRICING = {
-  'claude-opus-4-7':   { input:  5.00, output: 25.00, cache_write:  6.25, cache_read: 0.50 },
-  'claude-opus-4-6':   { input:  5.00, output: 25.00, cache_write:  6.25, cache_read: 0.50 },
-  'claude-opus-4-5':   { input:  5.00, output: 25.00, cache_write:  6.25, cache_read: 0.50 },
-  'claude-sonnet-4-7': { input:  3.00, output: 15.00, cache_write:  3.75, cache_read: 0.30 },
-  'claude-sonnet-4-6': { input:  3.00, output: 15.00, cache_write:  3.75, cache_read: 0.30 },
-  'claude-sonnet-4-5': { input:  3.00, output: 15.00, cache_write:  3.75, cache_read: 0.30 },
-  'claude-haiku-4-7':  { input:  1.00, output:  5.00, cache_write:  1.25, cache_read: 0.10 },
-  'claude-haiku-4-6':  { input:  1.00, output:  5.00, cache_write:  1.25, cache_read: 0.10 },
-  'claude-haiku-4-5':  { input:  1.00, output:  5.00, cache_write:  1.25, cache_read: 0.10 },
-};
+const PRICING = /*__PRICING_JSON__*/;
 
 function isBillable(model) {
   if (!model) return false;
@@ -1237,6 +1229,15 @@ def get_dashboard_data(db_path=DB_PATH):
 """
 
 
+def render_html():
+    """Inject the Python PRICING table into the HTML so the JS table
+    can never drift from the Python one."""
+    return HTML_TEMPLATE.replace(
+        "/*__PRICING_JSON__*/",
+        json.dumps(PRICING),
+    ).encode("utf-8")
+
+
 class DashboardHandler(BaseHTTPRequestHandler):
     def log_message(self, format, *args):
         pass
@@ -1246,7 +1247,7 @@ def do_GET(self):
             self.send_response(200)
             self.send_header("Content-Type", "text/html; charset=utf-8")
             self.end_headers()
-            self.wfile.write(HTML_TEMPLATE.encode("utf-8"))
+            self.wfile.write(render_html())
 
         elif self.path == "/api/data":
             data = get_dashboard_data()

pricing.py

@@ -0,0 +1,56 @@
+"""
+Anthropic API pricing — single source of truth for both the Python CLI cost
+calculator and the JavaScript dashboard.
+
+USD per million tokens. Updated April 2026.
+Source: https://docs.claude.com/en/docs/about-claude/pricing
+"""
+
+PRICING = {
+    "claude-opus-4-7":   {"input": 5.00, "output": 25.00, "cache_read": 0.50, "cache_write": 6.25},
+    "claude-opus-4-6":   {"input": 5.00, "output": 25.00, "cache_read": 0.50, "cache_write": 6.25},
+    "claude-opus-4-5":   {"input": 5.00, "output": 25.00, "cache_read": 0.50, "cache_write": 6.25},
+    "claude-sonnet-4-7": {"input": 3.00, "output": 15.00, "cache_read": 0.30, "cache_write": 3.75},
+    "claude-sonnet-4-6": {"input": 3.00, "output": 15.00, "cache_read": 0.30, "cache_write": 3.75},
+    "claude-sonnet-4-5": {"input": 3.00, "output": 15.00, "cache_read": 0.30, "cache_write": 3.75},
+    "claude-haiku-4-7":  {"input": 1.00, "output":  5.00, "cache_read": 0.10, "cache_write": 1.25},
+    "claude-haiku-4-6":  {"input": 1.00, "output":  5.00, "cache_read": 0.10, "cache_write": 1.25},
+    "claude-haiku-4-5":  {"input": 1.00, "output":  5.00, "cache_read": 0.10, "cache_write": 1.25},
+}
+
+
+def get_pricing(model):
+    """Look up per-MTok pricing for a model name.
+
+    Tries exact match, then prefix match, then keyword fallback (any name
+    containing 'opus'/'sonnet'/'haiku' falls back to the latest of that family).
+    Returns None for unknown / non-Anthropic models so callers can show 'n/a'.
+    """
+    if not model:
+        return None
+    if model in PRICING:
+        return PRICING[model]
+    for key in PRICING:
+        if model.startswith(key):
+            return PRICING[key]
+    m = model.lower()
+    if "opus" in m:
+        return PRICING["claude-opus-4-7"]
+    if "sonnet" in m:
+        return PRICING["claude-sonnet-4-6"]
+    if "haiku" in m:
+        return PRICING["claude-haiku-4-5"]
+    return None
+
+
+def calc_cost(model, inp, out, cache_read, cache_creation):
+    """Cost in USD for one batch of token usage. Returns 0 for unknown models."""
+    p = get_pricing(model)
+    if p is None:
+        return 0.0
+    return (
+        (inp or 0)            * p["input"]       / 1_000_000
+        + (out or 0)          * p["output"]      / 1_000_000
+        + (cache_read or 0)   * p["cache_read"]  / 1_000_000
+        + (cache_creation or 0) * p["cache_write"] / 1_000_000
+    )

tests/test_dashboard.py

@@ -233,16 +233,16 @@ class TestPricingParity(unittest.TestCase):
     """Verify CLI and dashboard pricing tables stay in sync."""
 
     def _extract_js_pricing(self):
-        """Extract pricing values from the dashboard JS PRICING object."""
-        import re
-        prices = {}
-        for match in re.finditer(
-            r"'(claude-[^']+)':\s*\{\s*input:\s*([\d.]+),\s*output:\s*([\d.]+)",
-            HTML_TEMPLATE
-        ):
-            model, inp, out = match.group(1), float(match.group(2)), float(match.group(3))
-            prices[model] = {"input": inp, "output": out}
-        return prices
+        """Decode the JSON-injected PRICING table from the rendered HTML.
+        The HTML_TEMPLATE now carries a placeholder; the real table is
+        injected at request time by render_html()."""
+        import re, json
+        from dashboard import render_html
+        html = render_html().decode("utf-8")
+        m = re.search(r"const PRICING = (\{.*?\});", html, re.DOTALL)
+        if not m:
+            return {}
+        return json.loads(m.group(1))
 
     def test_all_cli_models_in_dashboard(self):
         from cli import PRICING as CLI_PRICING