getting tags from the backend

src/context.zig

@@ -6,24 +6,28 @@ const Allocator = std.mem.Allocator;
 const builtin = @import("builtin");
 const optimize_mode = builtin.mode;
 
-db_connection: sqlite.Db,
+const model_tag = @import("./models/tag.zig");
+
+db_connection: *sqlite.Db,
 counter: u32 = 0,
 
-pub fn init(connection: sqlite.Db) @This() {
+pub fn init(connection: *sqlite.Db) !@This() {
+    try connection.execDynamic(model_tag.schema, .{}, .{});
     return .{
         .db_connection = connection,
     };
 }
 
-pub fn SendInertiaResponse(endpoint: anytype, context: ?*@This(), r: zap.Request, arena: Allocator, component: []const u8, props: anytype) !void {
-    _ = context;
+pub fn SendInertiaResponse(endpoint: anytype, context: *@This(), r: zap.Request, arena: Allocator, component: []const u8, props: anytype) !void {
+    const tags = try model_tag.getTopLevelTags(context.db_connection, arena);
+
     const inertia_json = try std.fmt.allocPrint(
         arena,
         "{f}",
         .{std.json.fmt(.{
             .component = component,
             .props = .{
-                .nav = .{},
+                .tags = tags,
                 .page = props,
             },
             .url = endpoint.path,

src/main.zig

@@ -1,9 +1,3 @@
-//!
-//! Part of the Zap examples.
-//!
-//! Build me with `zig build     app_basic`.
-//! Run   me with `zig build run-app_basic`.
-//!
 const std = @import("std");
 const Allocator = std.mem.Allocator;
 const builtin = @import("builtin");
@@ -77,9 +71,10 @@ pub fn main() !void {
         .threading_mode = .MultiThread,
     });
     defer db.deinit();
+    try db.execDynamic("PRAGMA foreign_keys = ON;", .{}, .{});
 
     // create an app context
-    var my_context = Context.init(db);
+    var my_context = try Context.init(&db);
 
     // create an App instance
     // const App = zap.App.Create(Context);

src/models/tag.zig

@@ -0,0 +1,81 @@
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+const builtin = @import("builtin");
+const optimize_mode = builtin.mode;
+
+const sqlite = @import("sqlite");
+
+pub const schema =
+    \\CREATE TABLE IF NOT EXISTS tag(
+    \\  id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    \\  key        TEXT UNIQUE NOT NULL,
+    \\  parent_key TEXT TEXT,
+    \\  FOREIGN KEY (parent_key) REFERENCES tag(key) ON DELETE RESTRICT
+    \\);
+;
+
+id: usize,
+key: []const u8,
+parent: ?*@This() = null,
+children: ?[]@This() = null,
+
+const internal = struct {
+    id: usize,
+    key: []const u8,
+    parent_key: ?[]const u8,
+};
+
+const ArrList = std.ArrayList(@This());
+
+pub fn getTopLevelTags(conn: *sqlite.Db, arena: Allocator) ![]@This() {
+    var stmt = try conn.prepareDynamic("SELECT id, key, parent_key FROM tag WHERE parent_key IS NULL;");
+    defer stmt.deinit();
+
+    var list = ArrList.empty;
+    defer list.deinit(arena);
+
+    var iter = try stmt.iterator(internal, .{});
+    while (try iter.nextAlloc(arena, .{})) |row| {
+        var tag: @This() = .{
+            .id = row.id,
+            .key = row.key,
+        };
+        try tag.getChildren(conn, arena);
+        try list.append(arena, tag);
+    }
+
+    return list.toOwnedSlice(arena);
+}
+
+pub fn getChildren(self: *@This(), conn: *sqlite.Db, arena: Allocator) !void {
+    var stmt = try conn.prepareDynamic("SELECT id, key, parent_key FROM tag WHERE parent_key LIKE ?;");
+    defer stmt.deinit();
+
+    var list = ArrList.empty;
+    defer list.deinit(arena);
+
+    var iter = try stmt.iterator(internal, .{self.key});
+    while (try iter.nextAlloc(arena, .{})) |row| {
+        var tag: @This() = .{
+            .id = row.id,
+            .key = row.key,
+        };
+        tag.parent = self;
+        try tag.getChildren(conn, arena);
+        try list.append(arena, tag);
+    }
+
+    self.children = try list.toOwnedSlice(arena);
+}
+
+pub fn jsonStringify(v: @This(), jws: anytype) !void {
+    try jws.beginObject();
+
+    try jws.objectField("key");
+    try jws.write(v.key);
+
+    try jws.objectField("children");
+    try jws.write(v.children);
+
+    try jws.endObject();
+}