在执行b接口前先执行a接口并把a接口返回值设置到局部环境参数中
①post请求
//请求参数
var data = {
"loginId":"SWGD_TEST",
"password":"888888a"
}
const echoPostRequest = {
//a接口路径
url: 'http://192.168.1.19/openlogin/getRefreshToken',
method: 'POST',
header:'Content-Type:application/json',
body: {
mode: 'raw',
raw: JSON.stringify(data)
}};
//发送请求
pm.sendRequest(echoPostRequest, function (err, res) {
console.log(res.json());
var refreshToken = res.json().data.refreshToken
pm.environment.set("refreshToken", refreshToken);
});

postman(六):详解在Pre-request Script中如何执行请求_51CTO博客_postman pre-request script
Postman + Pre-resuestScript:预请求脚本发送POST请求_丶凉的博客-优快云博客_postman pre-script脚本编写