refactor: cleanup JSON error handling

src/components/CreateButton.tsx

@@ -244,13 +244,8 @@ export const CreateButton = () => {
                     setBolt12Offer(undefined);
                     setInvoiceValid(true);
                 } catch (e) {
-                    const err: unknown =
-                        typeof e.json === "function"
-                            ? (await e.json()).error
-                            : e;
-
-                    notify("error", formatError(err));
-                    log.warn("Fetching invoice from bol12 failed", err);
+                    notify("error", formatError(e));
+                    log.warn("Fetching invoice from bol12 failed", e);
                     return;
                 }
             }
@@ -370,17 +365,11 @@ export const CreateButton = () => {
                 navigate("/swap/refund/" + data.id);
             }
         } catch (err) {
-            let msg = err;
-
-            if (typeof err.json === "function") {
-                msg = (await err.json()).error;
-            }
-
-            if (msg === "invalid pair hash") {
+            if (err === "invalid pair hash") {
                 setPairs(await getPairs());
                 notify("error", t("feecheck"));
             } else {
-                notify("error", msg);
+                notify("error", err);
             }
         }
     };

src/components/SwapChecker.tsx

@@ -293,9 +293,7 @@ export const SwapChecker = () => {
                     true,
                 );
             } catch (e) {
-                const err: unknown =
-                    typeof e.json === "function" ? (await e.json()).error : e;
-                if (err === "swap not eligible for a cooperative claim") {
+                if (e === "swap not eligible for a cooperative claim") {
                     log.debug(
                         `Server did not want help claiming ${currentSwap.id}`,
                     );
@@ -304,7 +302,7 @@ export const SwapChecker = () => {
 
                 const msg =
                     "creating cooperative signature for submarine swap claim failed";
-                log.warn(msg, err);
+                log.warn(msg, e);
                 notify("error", msg);
             }
         }

src/utils/claim.ts

@@ -186,18 +186,14 @@ export const createTheirPartialChainSwapSignature = async (
             ).toString("hex"),
         };
     } catch (err) {
-        if (typeof err.json !== "function") {
-            throw err;
+        if (err === "swap not eligible for a cooperative claim") {
+            log.debug(
+                `Backend already broadcast their claim for chain swap ${swap.id}`,
+            );
+            return undefined;
         }
 
-        const errMessage = (await err.json()).error;
-        if (errMessage !== "swap not eligible for a cooperative claim") {
-            throw err;
-        }
-
-        log.debug(
-            `backend already broadcast their claim for chain swap ${swap.id}`,
-        );
+        throw err;
     }
 
     return undefined;

src/utils/helper.ts

@@ -13,6 +13,7 @@ import {
     SubmarinePairTypeTaproot,
 } from "./boltzClient";
 import { ECPair } from "./ecpair";
+import { formatError } from "./errors";
 import { ChainSwap, ReverseSwap, SomeSwap, SubmarineSwap } from "./swapCreator";
 
 export const isIos = () =>
@@ -108,7 +109,14 @@ export const fetcher = async <T = unknown>(
     const apiUrl = getApiUrl() + url;
     const response = await fetch(apiUrl, opts);
     if (!response.ok) {
-        return Promise.reject(response);
+        try {
+            const body = await response.json();
+            return Promise.reject(formatError(body));
+
+            // eslint-disable-next-line @typescript-eslint/no-unused-vars
+        } catch (e) {
+            return Promise.reject(response);
+        }
     }
     return (await response.json()) as T;
 };

src/utils/refund.ts

@@ -171,18 +171,13 @@ const broadcastRefund = async <T extends SubmarineSwap | ChainSwap>(
         }
         return swap;
     } catch (e) {
-        const errorMsg = typeof e.json === "function" ? await e.json() : e;
-        if (errorMsg.error === undefined) {
-            throw e;
-        }
-
         // When the uncooperative refund transaction is not ready to be broadcast yet
         // (= non-final) and the cooperative spend has been tried but failed,
         // throw the error of the cooperative spend
-        throw errorMsg.error === "non-final" &&
+        throw e === "non-final" &&
             txConstructionResponse.cooperativeError !== undefined
             ? txConstructionResponse.cooperativeError
-            : errorMsg.error;
+            : e;
     }
 };