crypto fix

server/implementations/main.cpp

@@ -327,22 +327,47 @@ int main(int argc, char** argv) {
             out = Server::MakeRail(cfg);
             // "off" is a legitimate choice and yields no rail; a mode nobody
             // recognises silently would too, which is how a typo becomes a
-            // shop that quietly stops taking one kind of money.
+            // shop that quietly stops taking one kind of money. So an
+            // unrecognised mode is still a hard refusal — but a mode we DO
+            // recognise, failing on its runtime data, is not the same fault
+            // and must not be answered the same way (see below).
             if (!out && mode != "off") {
-                // "eurc" is the one mode that constructs to nullptr for a
-                // reason other than a typo — its chains file or address pool
-                // did not load, and MakeEurcRail has already said which and
-                // why. Repeating "unknown rail" over the top of that would
-                // send the operator looking for a spelling mistake.
-                if (mode == "eurc") {
-                    std::println(std::cerr,
-                                 "catcrafts-server: the eurc rail could not load its "
-                                 "chains file ({}) or address pool ({}) — see above",
-                                 eurcChainsPath.string(), eurcPoolPath.string());
-                } else {
+                static constexpr std::string_view kKnown[] = {
+                    "mollie", "eurc", "fake", "fake-crypto"
+                };
+                const bool known = std::ranges::find(kKnown, mode) != std::end(kKnown);
+                if (!known) {
                     std::println(std::cerr, "catcrafts-server: unknown rail '{}'", mode);
+                    return false;
                 }
-                return false;
+                // A KNOWN rail that could not load its data — for "eurc",
+                // its chains file or address pool. MakeEurcRail has already
+                // said which and why, so this only names the files.
+                //
+                // This is a WARNING and not a refusal, and the reason is the
+                // blast radius. An exhausted address pool is a state a
+                // stranger can drive the shop into (every crypto checkout
+                // spends an address), and answering it with "the process
+                // refuses to boot" turns a spent pool into the entire website
+                // down — every page, the bank rail included — held down by
+                // Restart=always until a human runs an offline wallet
+                // ceremony. That trade is never right: this box already
+                // "serves the whole site minus checkout" when no credentials
+                // exist at all (see the slot notes above), and one rail's
+                // data going bad is strictly less than that.
+                //
+                // Silent degradation is the other failure to avoid, so the
+                // warning is loud, the listening line below reports
+                // crypto=off, and tools/enable-eurc.sh refuses to call an
+                // enable successful without the rail's own load line.
+                std::println(std::cerr,
+                             "catcrafts-server: WARNING: the '{}' rail could not load "
+                             "its chains file ({}) or address pool ({}) — see above. "
+                             "CONTINUING WITHOUT IT: that payment choice is off and "
+                             "the rest of the site is unaffected.",
+                             mode, eurcChainsPath.string(), eurcPoolPath.string());
+                out.reset();
+                return true;
             }
             return true;
         };