src/App.js

@@ -1,5 +1,6 @@
 import React from 'react';
 import './App.css';
+import redditSlice from './features/reddit/redditSlice';
 
 function App() {
   return (

src/features/posts/postsSlice.js

@@ -1,10 +1,49 @@
-import { createSlice } from "@reduxjs/toolkit";
+import { createSlice, createAsyncThunk } from "@reduxjs/toolkit";
+
+export const fetchBySub = createAsyncThunk(
+    'reddit/fetchBySub',
+    async(subreddit) => {    // expects an argument corresponding to the url, in json format, of a given subreddit
+        try {
+            const myRequest = new Request(subreddit);   // initializes request
+            let response = await fetch(myRequest);
+            let json = await response.json();
+            let postsArray = json.data.children;        // unpacks individual post objects from the subreddit JSON file, as an array
+            return postsArray;
+        } catch(e) {
+            console.log(e);
+        }
+    }
+);
 
 export const postsSlice = createSlice({
     name: 'posts',
-    initialState: {},
-    reducers: {},
-    extraReducers: {},
+    initialState: {
+        posts: [],
+        requestsPending: false,
+        requestDenied: false,
+    },
+    reducers: {
+        filterPosts(state,action) {             // Expects action.payload to be the searchterm imported from the state of searchBar
+            state.posts.filter(post => (post.data.title !== action.payload) && (post.data.selftext !== action.payload));
+        }
+    },
+    extraReducers: (builder) => {
+        builder.addCase(fetchBySub.pending, (state,action) => {
+            state.requestsPending = true;
+            state.requestDenied = false;
+        })
+        builder.addCase(fetchBySub.rejected, (state,action) => {
+            state.requestsPending = false;
+            state.requestDenied = true;
+        })
+        builder.addCase(fetchBySub.fulfilled, (state,action) => {
+            state.requestsPending = false;
+            state.requestDenied = false;
+            for (let sub in action.payload) {       // iterates over postsArray to avoid
+                state.posts.push(sub);              // nesting arrays within the state's posts
+            }
+        })
+    }
 });
 
 export default postsSlice.reducer;