README update, pagination

jxmot · jxmot · commit 739638bb75e4 · 2020-12-17T02:27:57.000-06:00
diff --git a/pagination/README.md b/pagination/README.md
@@ -1,2 +1,87 @@
 # GraphQL Pagination
 
+## Queries and Pagination
+
+It took me a bit to understand how *pagination* works under the GitHub's implementation of GraphQL. Honestly it isn't that difficult. But the available documentation does not seem to provide any *workable* examples or a very clear explanation.
+
+The GitHub GraphQL uses the *Complete Connection Model* method of pagination. Which is partially descrbed [here](https://graphql.github.io/learn/pagination/#complete-connection-model). 
+
+Pagination Examples:
+
+* **`/queries/user-verified-pagination-starred_repos.graphql`** : retrieves the validated user's list of starred repos where pagination can applied.
+
+### Pagination in Detail
+
+Using the **`/queries/user-verified-pagination-starred_repos.graphql`** file I will attempt to explain how pagination works under the GitHub GraphQL API.
+
+First, open a GraphQL *explorer*. This example should also work with GitHub's [GraphQL Explorer](https://docs.github.com/en/free-pro-team@latest/graphql/overview/explorer). Open the Explorer and *paste* the following into it:
+
+The query:
+
+```
+query($fst:Int, $lst:Int, $aft:String, $bef:String) {
+  viewer {
+    login
+    name
+    starredRepositories(orderBy: {direction: DESC, field: STARRED_AT},
+                        first: $fst,
+                        last: $lst,
+                        after: $aft,
+                        before: $bef) {
+      totalCount
+      pageInfo {
+        hasNextPage
+        endCursor
+        hasPreviousPage
+        startCursor
+      }
+      edges {
+        starredAt
+        node {
+          name
+          stargazerCount
+          primaryLanguage {
+            name
+            color
+          }
+        }
+      }
+    }
+  }
+}
+```
+
+Variables needed by the query, paste this into the *query variables* pane :
+
+```
+{
+  "fst": 3,
+  "lst": null,
+  "aft": null,
+  "bef": null
+}
+```
+
+To see how pagination works use these steps:
+
+  1) Run the query with the data as shown below
+  2) After the successful query, copy the string from the 
+     result at `pageInfo.endCursor` into the `aft` data item
+  3) Run the query again
+  4) The next "page" will be returned
+
+  Steps 2 - 4 can be repeated until `pageInfo.hasNextPage` 
+  becomes `false`.
+
+  5) To go to the previous page copy the string from the result
+     at `pageInfo.startCursor` into the `bef` data item
+  6) Set `aft` to `null`
+  7) Set `fst` to `null`
+  8) Set `lst` to 3
+  9) Run the query again
+ 10) The previous "page" will be returned
+
+  Steps 6 - 9 can be repeated until `pageInfo.hasPreviousPage` 
+  becomes `false`.
+
+**NOTE**: You will need to have some starred repositories under your account. The minimum recommended for this demonstration is 12. If you have a lot of starred repos change the value used in `"fst"` and `"lst"` to a larger value. For example, if you had 100 starred repos you could change that value from `3` to `25`. That would give you 4 pages of 25 items.
