我在使用AWS Lambda函数查询MySQL数据库（从AWS远程托管）时遇到问题。
这是我的代码，除了Lambda函数的其余部分所需的部分（正在为Alexa技能调用）：
var mysql = require('mysql');
var connection = mysql.createConnection({
host : '<myserver>',
user : '<myusername>',
password : '<mypw>',
database : '<mydatabase>'
});
connection.connect(function(err){
if(!err) {
console.log("Database is connected ... nn");
}
else {
console.log("Error connecting database ... nn");
}
});
connection.query("INSERT INTO Users (user_id) VALUES ('TESTNAME')");
connection.end();
当我从命令提示符运行节点时，这很好用：
node index.js
我正在使用通过npm在index.js目录下安装的“mysql”模块并将其压缩并上传到我的Lambda函数。
同样，这可以在我的开发机器上运行，但在测试我的Lambda函数时没有给出任何指示，因为它根本不会影响我的数据库。
我的问题扩展到了Alexa和Lambda，就像正确使用mysql Node.JS模块一样。
这是我当前的Lambda代码，当然这里的问题仍然是我的测试值 - ＆gt;名为“TESTNAME”的用户名不会添加到我的MySQL数据库中。
我将查询放入连接回调中，正如第一条评论所暗示的那样，我正在使用我的新代码而不是更新上面的旧代码，只是为了记录我认为代码应该如何转换为我的代码。 Alexa的Lambda功能：
更新的代码：
var mysql = require('mysql');
var connection = mysql.createConnection({
host : '<myserver>',
user : '<myusername>',
password : '<mypw>',
database : '<mydatabase>'
});
exports.handler = (event, context) => {
try {
if (event.session.new) {
// New Session
console.log("NEW SESSION");
}
switch (event.request.type) {
case "LaunchRequest":
// Launch Request
console.log(`LAUNCH REQUEST`);
context.succeed(
generateResponse({},
buildSpeechletResponse("Welcome to an Alexa Skill, this is running on a deployed lamda function", true)
)
);
break;
case "IntentRequest":
// Intent Request
console.log(`Intent Request`);
console.log('Then run MySQL code:');
connection.connect(function(err) {
console.log('Inside connection.connect() callback');
if (!err) {
console.log("Database is connected ... ");
connection.query("INSERT INTO Users (user_id) VALUES ('TESTNAME')",
function(err, result) {
console.log("Inside connection.query() callback")
if (!err) {
console.log("Query Successful! Ending Connectection.");
connection.end();
} else {
console.log("Query error!");
}
});
} else {
console.log("Error connecting database ..." + err.message);
}
});
context.succeed(
generateResponse({},
buildSpeechletResponse("Welcome to the incredible intelligent MySQLable Alexa!", true)
)
);
break;
case "SessionEndedRequest":
// Session Ended Request
console.log(`SESSION ENDED REQUEST`);
break;
default:
context.fail(`INVALID REQUEST TYPE: ${event.request.type}`);
}
} catch (error) {
context.fail(`Exceptiodn: ${error}`)
}
};
//Helpers
buildSpeechletResponse = (outputText, shouldEndSession) => {
return {
outputSpeech: {
type: "PlainText",
text: outputText
},
shouldEndSession: shouldEndSession
};
};
generateResponse = (sessionAttributes, speechletResponse) => {
return {
version: "1.0",
sessionAttributes: sessionAttributes,
response: speechletResponse
};
};
我的控制台输出：
START RequestId: 5d4d17a7-0272-11e7-951c-b3d6944457e1 Version: $LATEST
2017-03-06T13:39:47.561Z 5d4d17a7-0272-11e7-951c-b3d6944457e1 Intent Request
2017-03-06T13:39:47.562Z 5d4d17a7-0272-11e7-951c-b3d6944457e1 Then run MySQL code:
END RequestId: 5d4d17a7-0272-11e7-951c-b3d6944457e1
REPORT RequestId: 5d4d17a7-0272-11e7-951c-b3d6944457e1 Duration: 82.48 ms Billed Duration: 100 ms Memory Size: 128 MB Max Memory Used: 14 MB
答案 0 :(得分：4)
问题是我需要将context.succeed放在回调中。非常感谢sqlbot，因为他对回调的讨论让我研究了事情实际上已经结束了他们的执行。
显然，在使用AWS Lambda时，如果“回调”被调用之前“上下文”结束，则不会得到回调。所以即使我把所有的回调都放在了这样的地方：connect - ＆gt;查询 - ＆gt;结束，来自connect的链的第一个回调永远不会被调用，因为“context.succeed”之后被调用，结束了执行。
这是我现在的代码（现在正在进行正确的查询）：
var mysql = require('mysql');
var connection = mysql.createConnection({
...
});
exports.handler = (event, context) => {
try {
if (event.session.new) {
// New Session
console.log("NEW SESSION");
}
switch (event.request.type) {
case "LaunchRequest":
// Launch Request
console.log(`LAUNCH REQUEST`);
context.succeed(
generateResponse({},
buildSpeechletResponse("Welcome to an Alexa Skill, this is running on a deployed lamda function", true)
)
);
break;
case "IntentRequest":
// Intent Request
console.log(`Intent Request`);
console.log('Then run MySQL code:');
connection.connect(function(err) {
console.log('Inside connection.connect() callback');
if (!err) {
console.log("Database is connected ... ");
connection.query("INSERT INTO Users (user_id) VALUES ('TESTNAME')",
function(err, result) {
console.log("Inside connection.query() callback")
if (!err) {
console.log("Query Successful! Ending Connection.");
connection.end();
} else {
console.log("Query error!");
}
});
} else {
console.log("Error connecting database ..." + err.message);
}
context.succeed(
generateResponse({},
buildSpeechletResponse("Welcome to the incredible intelligent MySQLable Alexa!", true)
)
);
});
break;
case "SessionEndedRequest":
// Session Ended Request
console.log(`SESSION ENDED REQUEST`);
break;
default:
context.fail(`INVALID REQUEST TYPE: ${event.request.type}`);
}
} catch (error) {
context.fail(`Exceptiodn: ${error}`)
}
};
//Helpers
buildSpeechletResponse = (outputText, shouldEndSession) => {
return {
outputSpeech: {
type: "PlainText",
text: outputText
},
shouldEndSession: shouldEndSession
};
};
generateResponse = (sessionAttributes, speechletResponse) => {
return {
version: "1.0",
sessionAttributes: sessionAttributes,
response: speechletResponse
};
};