JavaScript-传递AWS Lambda函数的查询参数
作者:互联网
我正在尝试设置一个Lambda函数,该函数将提取传递到创建的API网关URL中的查询参数. (侧边栏:在编程方面,我还是很环保的,所以请原谅我对如何命名事物的任何无意的困惑).我已经使用Synchronize.JS在光纤中包装了一些REST调用,当我对要传递到各个REST URL中的变量进行硬编码时,它的工作效果很好,但是我们的目标是能够传递将充当进行不同的REST调用的全局变量.这就是我目前拥有的…
// Dependendies
var request = require('superagent');
var sync = require('synchronize');
exports.handler = function(event, context) {
sync.fiber(function() {
var followingArray = [];
var followersArray = [];
var postsCountArray = [];
var allSqorCountArray = [];
var trendingPostAuthorArray = [];
var hashtagCountArray = [];
var notificationCountArray = [];
var getParam = function(query){
var SearchString = window.location.search.substring(1);
var VariableArray = SearchString.split('&');
for(var i = 0; i < VariableArray.length; i++){
var KeyValuePair = VariableArray[i].split('=');
if(KeyValuePair[0] == query){
return KeyValuePair[1];
}
};
};
var userId = getParam('userId');
var limit = getParam('limit');
var offset = getParam('offset');
var restCallOne = function() {
request('https://someurl.com/etc/' + userId + '/follows?limit=' + limit + '&offset=' + offset)
.end(function(err, res) {
if (err) {
console.log('Request 1');
context.fail("Danger Will Robinson!!! Follows Count Does Not Like You!!");
} else {
var followsCount = res.body.total_count;
followingArray.push(followsCount);
}
});
};
var restCallTwo = function() {
request
.get('https://someurl.com/etc/etc/etc?limit=' + limit + '&offset=' + offset)
.set({'access-token': 'someAccessToken'})
.end(function(err, res) {
if(err) {
console.log('Request 4');
context.fail("Danger Will Robinson!! The All Sqor Feed is moody");
} else {
var allSqorCount = res.body.total_count;
allSqorCountArray.push(allSqorCount);
}
});
};
var restCallThree = function() {
request
.get('https://someUrl.com/etc/' + userId + '/followers?limit=' + limit + '&offset=' + offset)
.end(function(err, res) {
if (err) {
console.log('Request 3');
context.fail("Danger Will Robinson!!! Following Count Done Smacked You Upside The Head!!");
} else {
var count = res.body.total_count;
followersArray.push(count);
context.done(null, 'The total number of people that follow Andy is ' + followersArray[0] +
', and the number of people that Andy follows is ' + followingArray[0] +
', and the number of posts in his feed is ' + allSqorCountArray[0]);
}
});
};
try {
restCallOne(userId, limit, offset);
} catch(errOne) {
console.log("Error on call 1!!");
}
try {
restCallTwo(limit, offset);
} catch(errTwo) {
console.log("Error on call 2!!");
}
try {
restCallThree(userId, limit, offset);
} catch(errThree) {
console.log("Error on call 3!!");
}
});
};
当我将此函数链接时生成的API网关URL如下:https://someID.execute-api.us-east-1.amazonaws.com/syncFunctionalParams
但我希望能够传递这样的信息,并在Lambda函数中使用params从其余的调用中返回正确的信息:
https://someID.execute-api.us-east-1.amazonaws.com/syncFunctionalParams?userId=212733&limit=25&offset=0
这可能吗??我会偏离这个方向吗?
解决方法:
您需要在API网关中设置mapping template.如果您提前知道参数的名称,则模板可能如下所示:
{
"userId": "$input.params('userId')",
"limit": "$input.params('limit')",
"offset": "$input.params('offset')"
}
当事件传递给Lambda时,将评估每个$input.params(‘…’)的位置,并将查询字符串中的值放在其位置.
如果您不提前知道参数名称,则必须在Lambda中进行一些解析.您的映射模板如下所示:
{
"querystring": "$input.params().querystring"
}
在传递给Lambda的事件中,最终看起来像这样:
{
"querystring": "{limit=25, offset=0, userId=212733}"
}
然后,您将解析getParam()中的event.querystring而不是window.location.search.显然,您将需要更改一些逻辑,因为您将使用逗号而不是&符进行分隔,并且需要除去花括号.顺便说一下,由于您目前在服务器上,因此您没有窗口对象.
标签:aws-lambda,aws-api-gateway,javascript 来源: https://codeday.me/bug/20191119/2035533.html