Implement basic JSON parsing functions

src/json.zig

@@ -31,6 +31,12 @@ pub const Obj = struct {
         return Obj{ .obj = c.json_tokener_parse(s).? };
     }
 
+    // Not *const Obj because the json_object retains ownership of the string
+    pub fn getString(self: *Obj) []const u8 {
+        // TODO: Check type to not allow other types
+        return std.mem.sliceTo(c.json_object_get_string(self.obj), 0);
+    }
+
     pub fn deinit(self: *Obj) void {
         _ = c.json_object_put(self.obj);
     }
@@ -54,6 +60,14 @@ pub const Obj = struct {
         return Obj{ .obj = c.json_object_get(obj).? };
     }
 
+    pub fn objectGetIterator(self: *Obj) ObjectIterator {
+        // TODO: Check errors
+        return ObjectIterator{
+            .it = c.json_object_iter_begin(self.obj),
+            .end = c.json_object_iter_end(self.obj),
+        };
+    }
+
     pub fn objectAdd(self: *Obj, key: [*c]const u8, value: ?*Obj) void {
         // TODO: Check type and error return
 
@@ -63,6 +77,38 @@ pub const Obj = struct {
         _ = c.json_object_object_add(self.obj, key, o);
     }
 
+    pub const ObjectIterator = struct {
+        it: c.json_object_iterator,
+        end: c.json_object_iterator,
+
+        const ReturnType = struct {
+            key: []const u8,
+            value: ?Obj,
+        };
+
+        // These function's names are way too long ._.
+        const step = c.json_object_iter_next;
+        const equal = c.json_object_iter_equal;
+        const peekName = c.json_object_iter_peek_name;
+        const peekValue = c.json_object_iter_peek_value;
+
+        /// Step the iterator. The owner mustn't call deinit() on the returned value.
+        pub fn next(self: *ObjectIterator) ?ReturnType {
+            const it = &self.it;
+            const end = &self.end;
+
+            // Reached the end
+            if (equal(it, end) != 0) return null;
+
+            defer step(it);
+
+            return ReturnType{
+                .key = std.mem.sliceTo(peekName(it), 0),
+                .value = if (peekValue(it)) |val| Obj{ .obj = val } else null,
+            };
+        }
+    };
+
     ///////////////////////////////////
     // ** Array functions **
     /////////////////////////////////

src/main.zig

@@ -32,8 +32,18 @@ pub fn main() !void {
     //try item.persist(&db);
 
     //var jobj = item.toJson();
+
     var jobj = jsonItem.objectGet("tags");
     defer jobj.deinit();
 
-    std.debug.print("{s}\n", .{jobj.toString()});
+    var iter = jobj.objectGetIterator();
+    while(iter.next()) |*tag| {
+        std.debug.print("{s}", .{tag.key});
+        defer std.debug.print("\n", .{});
+
+        if (tag.value) |*value| {
+            std.debug.print(" => {s}", .{value.getString()});
+        }
+    }
+
 }