refactor(services, types): reorganize GraphQL fetchers and data types

The Typescript mapped types was useful for autocompletion in fetchers
but their are harder to maintain. I think it's better to keep each
query close to its fetcher to have a better understanding of the
fetched data. So I:
* colocate queries with their own fetcher
* colocate mutations with their own mutator
* remove Typescript mapped types for queries and mutations
* move data convertors inside graphql services
* rename most of data types and fetchers

1 files changed, 92 insertions, 0 deletions

diff --git a/src/services/graphql/fetchers/posts/fetch-post.ts b/src/services/graphql/fetchers/posts/fetch-post.ts
new file mode 100644
index 0000000..53c6bc3
--- /dev/null
+++ b/src/services/graphql/fetchers/posts/fetch-post.ts
@@ -0,0 +1,92 @@
+import type { Nullable, WPPost } from '../../../../types';
+import { fetchGraphQL, getGraphQLUrl } from '../../../../utils/helpers';
+
+type PostResponse = {
+  post: Nullable<WPPost>;
+};
+
+const postQuery = `query Post($slug: ID!) {
+  post(id: $slug, idType: SLUG) {
+    acfPosts {
+      postsInThematic {
+        ... on Thematic {
+          databaseId
+          slug
+          title
+        }
+      }
+      postsInTopic {
+        ... on Topic {
+          databaseId
+          featuredImage {
+            node {
+              altText
+              mediaDetails {
+                height
+                width
+              }
+              sourceUrl
+              title
+            }
+          }
+          slug
+          title
+        }
+      }
+    }
+    author {
+      node {
+        name
+      }
+    }
+    commentCount
+    contentParts {
+      afterMore
+      beforeMore
+    }
+    databaseId
+    date
+    featuredImage {
+      node {
+        altText
+        mediaDetails {
+          height
+          width
+        }
+        sourceUrl
+        title
+      }
+    }
+    info {
+      wordsCount
+    }
+    modified
+    seo {
+      metaDesc
+      title
+    }
+    slug
+    title
+  }
+}`;
+
+/**
+ * Retrieve a WordPress post by slug.
+ *
+ * @param {string} slug - The post slug.
+ * @returns {Promise<WPPost>} The requested post.
+ */
+export const fetchPost = async (slug: string): Promise<WPPost> => {
+  const response = await fetchGraphQL<PostResponse>({
+    query: postQuery,
+    url: getGraphQLUrl(),
+    variables: { slug },
+  });
+
+  if (!response.post)
+    return Promise.reject(
+      new Error(`No post found for the following slug ${slug}.`)
+    );
+
+  return response.post;
+};