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, 34 insertions, 0 deletions

diff --git a/src/services/graphql/fetchers/thematics/fetch-all-thematics-slugs.ts b/src/services/graphql/fetchers/thematics/fetch-all-thematics-slugs.ts
new file mode 100644
index 0000000..739c009
--- /dev/null
+++ b/src/services/graphql/fetchers/thematics/fetch-all-thematics-slugs.ts
@@ -0,0 +1,34 @@
+import type { GraphQLNodes, Nullable, SlugNode } from '../../../../types';
+import { fetchGraphQL, getGraphQLUrl } from '../../../../utils/helpers';
+import { fetchThematicsCount } from './fetch-thematics-count';
+
+type ThematicsSlugsResponse = {
+  thematics: Nullable<GraphQLNodes<SlugNode>>;
+};
+
+const thematicsSlugsQuery = `query ThematicsSlugs($first: Int) {
+  thematics(first: $first) {
+    nodes {
+      slug
+    }
+  }
+}`;
+
+/**
+ * Retrieve the WordPress thematics slugs.
+ *
+ * @returns {Promise<string[]>} The thematics slugs.
+ */
+export const fetchAllThematicsSlugs = async (): Promise<string[]> => {
+  const thematicsCount = await fetchThematicsCount();
+  const response = await fetchGraphQL<ThematicsSlugsResponse>({
+    query: thematicsSlugsQuery,
+    url: getGraphQLUrl(),
+    variables: { first: thematicsCount },
+  });
+
+  if (!response.thematics)
+    return Promise.reject(new Error('Unable to find the thematics slugs.'));
+
+  return response.thematics.nodes.map((node) => node.slug);
+};