Warmup

zero framework offers built-in support to handle any synchronous tasks that has to be completed before serving any requests.

It can be achieved using the onStatup method of the App.

method signature

try app.onStatup(custom-handler);

Example

1. Refer following zero-redis example further to know more on getting started of this.

main.zig

pub fn main() !void {
    var arena_instance = std.heap.ArenaAllocator.init(std.heap.page_allocator);
    defer arena_instance.deinit();

    const allocator = arena_instance.allocator();

    const app = try App.new(allocator);

    try app.onStatup(prepareCache);

    try app.get("/redis", cacheResponse);

    try app.run();
}

fn prepareCache(ctx: *Context) !void {
    ctx.info("warming up the cache entries");

    _ = ctx.Cache.send(void, .{ "SET", "msg", "zero redis message" }) catch |err| {
        ctx.any(err);
    };

    // intentional delay to mimic cache preparation
    std.Thread.sleep(std.time.ns_per_s);

    ctx.info("cache prepared");
}

const Data = struct {
    msg: []const u8,
};

fn cacheResponse(ctx: *Context) !void {
    const reply = try ctx.Cache.sendAlloc([]u8, ctx.allocator, .{ "GET", "msg" });
    defer ctx.allocator.free(reply);

    try ctx.json(reply);
}

Check out the zero-redis example code to understand the usage better

Recommendation

🚩 It is highly recommended to use the ctx allocator whenever possible, since it is tied up with request life-cycle, the de-allocation will be managed automatically and making sure the memory leak is not happening.