add fetch all (closes #49)

Author: yringler

example/.gitignore

@@ -9,6 +9,7 @@
 .buildlog/
 .history
 .svn/
+*flutter_export_environment*
 
 # IntelliJ related
 *.iml

lib/flutter_wordpress.dart

@@ -243,6 +243,9 @@ class WordPress {
   ///
   /// (**Note:** *Set only those fetch boolean parameters which you need because
   /// the more information to fetch, the longer it will take to return all Posts*)
+  /// 
+  /// [fetchAll] will make as many API requests as is needed to get all posts.
+  /// This may take a while.
   ///
   /// In case of an error, a [WordPressError] object is thrown.
   async.Future<List<Post>> fetchPosts({
@@ -256,8 +259,14 @@ class WordPress {
     bool fetchFeaturedMedia = false,
     bool fetchAttachments = false,
     String postType = "posts",
+    bool fetchAll = false
   }) async {
-    final StringBuffer url = new StringBuffer(_baseUrl + URL_WP_BASE + "/" + postType);
+    if (fetchAll) {
+      postParams = postParams.copyWith(perPage: 100);
+    }
+
+    final StringBuffer url =
+        new StringBuffer(_baseUrl + URL_WP_BASE + "/" + postType);
 
     url.write(postParams.toString());
 
@@ -280,6 +289,25 @@ class WordPress {
           setAttachments: fetchAttachments,
         ));
       }
+
+      if (fetchAll && response.headers["X-WP-TotalPages"] != null) {
+        final totalPages = int.parse(response.headers["X-WP-TotalPages"]);
+
+        for (int i = postParams.pageNum + 1; i <= totalPages; ++i) {
+            posts.addAll(await fetchPosts(
+              postParams: postParams.copyWith(pageNum: i),
+              fetchAuthor: fetchAuthor,
+              fetchComments: fetchComments,
+              orderComments: orderComments,
+              orderCommentsBy: orderCommentsBy,
+              fetchCategories: fetchCategories,
+              fetchTags: fetchTags,
+              fetchFeaturedMedia: fetchFeaturedMedia,
+              fetchAttachments: fetchAttachments,
+            ));
+          }
+        }
+
       return posts;
     } else {
       try {
@@ -534,7 +562,11 @@ class WordPress {
   ///
   /// In case of an error, a [WordPressError] object is thrown.
   async.Future<List<Category>> fetchCategories(
-      {@required ParamsCategoryList params}) async {
+      {@required ParamsCategoryList params, bool fetchAll = false}) async {
+    if (fetchAll) {
+      params = params.copyWith(perPage: 100);
+    }
+
     final StringBuffer url = new StringBuffer(_baseUrl + URL_CATEGORIES);
 
     url.write(params.toString());
@@ -547,6 +579,16 @@ class WordPress {
       list.forEach((category) {
         categories.add(Category.fromJson(category));
       });
+
+      if (fetchAll && response.headers["X-WP-TotalPages"] != null) {
+        final totalPages = int.tryParse(response.headers["X-WP-TotalPages"]) ?? 1;
+
+        for (int i = params.pageNum + 1; i <= totalPages; ++i) {
+          categories.addAll(await fetchCategories(
+            params: params.copyWith(pageNum: i)));
+        }
+      }
+
       return categories;
     } else {
       try {
@@ -652,7 +694,7 @@ class WordPress {
   }
 
 //  yahya - @mymakarim
-  
+
   async.Future<dynamic> uploadMedia(File image) async {
     final StringBuffer url = new StringBuffer(_baseUrl + URL_MEDIA);
     var file = image.readAsBytesSync();
@@ -678,7 +720,7 @@ class WordPress {
       }
     }
   }
-  
+
 // uploadMedia function added by: @GarvMaggu
 
   async.Future<bool> createUser({@required User user}) async {

lib/requests/params_category_list.dart

@@ -50,6 +50,26 @@ class ParamsCategoryList {
     };
   }
 
+  ParamsCategoryList copyWith({
+    int pageNum,
+    int perPage
+  }) {
+    return ParamsCategoryList(
+      context: context,
+      order: order,
+      orderBy: orderBy,
+      pageNum: pageNum ?? this.pageNum,
+      perPage: perPage ?? this.perPage,
+      searchQuery: searchQuery,
+      slug: slug,
+      excludeCategoryIDs: excludeCategoryIDs,
+      hideEmpty: hideEmpty,
+      includeCategoryIDs: includeCategoryIDs,
+      parent: parent,
+      post: post
+    );
+  }
+
   @override
   String toString() {
     return constructUrlParams(toMap());

lib/requests/params_post_list.dart

@@ -74,6 +74,34 @@ class ParamsPostList {
     };
   }
 
+ParamsPostList copyWith({
+  int pageNum ,
+  int perPage,
+}) {
+  return ParamsPostList(
+    afterDate: afterDate,
+    beforeDate: beforeDate,
+    context: context,
+    excludeAuthorIDs: excludeAuthorIDs,
+    excludeCategories: excludeCategories,
+    excludePostIDs: excludePostIDs,
+    excludeTags: excludeTags,
+    includeAuthorIDs: includeAuthorIDs,
+    includeCategories: includeCategories,
+    includePostIDs: includePostIDs,
+    includeTags: includeTags,
+    offset: offset,
+    order: order,
+    orderBy: orderBy,
+    pageNum: pageNum ?? this.pageNum,
+    perPage: perPage ?? this.perPage,
+    postStatus: postStatus,
+    searchQuery: searchQuery,
+    slug: slug,
+    sticky: sticky
+  );
+}
+
   @override
   String toString() {
     return constructUrlParams(toMap());