spring cloud gateway常用的断言，以及分别代码示例

Spring Cloud Gateway 常用的断言有以下几种：

1. `after`：判断请求是否在指定时间之后

示例代码：

gatewayFilterChain.filter(exchange).then(Mono.fromRunnable(() -> {
    ZonedDateTime dateTime = ZonedDateTime.parse("2022-01-01T00:00:00+08:00");
    assertThat(exchange.getRequest().getHeaders().getDate()).isAfter(dateTime);
}));

2. `before`：判断请求是否在指定时间之前

示例代码：

gatewayFilterChain.filter(exchange).then(Mono.fromRunnable(() -> {
    ZonedDateTime dateTime = ZonedDateTime.parse("2022-01-01T00:00:00+08:00");
    assertThat(exchange.getRequest().getHeaders().getDate()).isBefore(dateTime);
}));

3. `cookie`：判断请求是否包含指定名称和值的 Cookie

示例代码：

gatewayFilterChain.filter(exchange).then(Mono.fromRunnable(() -> {
    assertThat(exchange.getRequest().getCookies().get("name").getValue()).isEqualTo("value");
}));

4. `header`：判断请求是否包含指定名称和值的 Header

示例代码：

gatewayFilterChain.filter(exchange).then(Mono.fromRunnable(() -> {
    assertThat(exchange.getRequest().getHeaders().get("name")).isEqualTo("value");
}));

5. `host`：判断请求是否包含指定 Host 值

示例代码：

gatewayFilterChain.filter(exchange).then(Mono.fromRunnable(() -> {
    assertThat(exchange.getRequest().getHeaders().getHost().getHostName()).isEqualTo("example.com");
}));