Update readme and improve error handling

README.md

@@ -1 +1,24 @@
-# social-links-bot
+# social-links-bot
+
+A Devvit app that responds to user lists and returns their social links (if any).
+
+Object type returned is an array of the following type:
+
+```ts
+interface UserSocialLinks {
+    username?: string;
+    error?: string;
+    errorDetail?: string;
+    socialLinks?: UserSocialLink[];
+}
+```
+
+Input is in the form of a JSON array of string e.g. `["user1", "user2"]`. Usernames are not case sensitive.
+
+If all is well, the error/errorDetail attributes are omitted.
+
+If the input is badly formed (e.g. not JSON, not a string array, containing entries that are impossible usernames (too short/long), or contains duplicate items), `error` and `errorDetail` attributes are returned in a single array item.
+
+Otherwise, an array of usernames with their social links (if any) is returned.
+
+Shadowbanned, suspended and deleted users cannot be retrieved, in which case their username and an error of "SHADOWBANNED" is returned.

devvit.yaml

@@ -1,2 +1,2 @@
 name: social-links-bot
-version: 0.0.14
+version: 0.0.17

src/main.ts

@@ -132,33 +132,33 @@ Devvit.addTrigger({
         }
 
         const userSocialLinks: UserSocialLinks[] = [];
-        let userList: string[] = [];
-        try {
-            userList = JSON.parse(event.comment.body) as string[];
-        } catch (error) {
-            userSocialLinks.push({
-                error: "INVALID_JSON",
-                errorDetail: error instanceof Error ? JSON.stringify(error.message) : undefined,
-            });
-        }
-
-        const ajv = new Ajv.default();
-        const validate = ajv.compile(schema);
 
-        if (!validate(userList)) {
-            userSocialLinks.push({
-                error: "JSON_INVALID_FORMAT",
-                errorDetail: ajv.errorsText(validate.errors),
-            });
-        } else {
-            for (const user of userList) {
-                userSocialLinks.push(await getSocialLinksForUser(user, context));
+        try {
+            const userList = JSON.parse(event.comment.body) as string[];
+
+            const ajv = new Ajv.default();
+            const validate = ajv.compile(schema);
+
+            if (!validate(userList)) {
+                userSocialLinks.push({
+                    error: "JSON_INVALID_FORMAT",
+                    errorDetail: ajv.errorsText(validate.errors),
+                });
+            } else {
+                for (const user of userList) {
+                    userSocialLinks.push(await getSocialLinksForUser(user, context));
+                }
             }
-        }
 
-        if (userSocialLinks.length === 0) {
+            if (userSocialLinks.length === 0) {
+                userSocialLinks.push({
+                    error: "NO_USERS_PROVIDED",
+                });
+            }
+        } catch (error) {
             userSocialLinks.push({
-                error: "NO_USERS_PROVIDED",
+                error: "INVALID_JSON",
+                errorDetail: error instanceof Error ? error.message : undefined,
             });
         }