MongoDB HTTPS Endpoints - access querystring in function - mongodb

Question

I have an HTTPS endpoint in MongoDB Realm. How can I get the values of individual query string parameters inside a function? I'm trying to use the Request object, but I can only get back the entire querystring.
Sample URL: https:///endpoint/search?param1=apple&param2=banana
The endpoint calls the function:
exports = function(){
query = context.request.rawQueryString;
return {query};
};
A GET request to the endpoint returns:
{
"query": "param1=apple&param2=banana"
}
How can I modify my function to get values of a named query string parameter, e.g.?
const queryParam1 = request.query.param1 would evaluate to "apple".
Thank you.

Answer 1

Grab the specific fields from the query object:
const {value1, value2} = query;
I believe the variable names need to match the query string parameters. For example, assume the following CURL command (notice the query string parameters):
curl --include \
--verbose \
--header "Accept: application/json" \
--header "Content-Type: application/json" \
--request POST "https://eastus2.azure.data.mongodb-api.com/app/simplewebservice-ryzao/endpoint/test?queryStringParam1=abc&queryStringParam2=123" \
--data '{ "fieldA": { "$int": "1" }, "fieldB": {"$date": "2022-09-26T22:20:17.123Z" } }'
Because I have two query string parameters I need to catch them using their specific names - queryStringParam1 and queryStringParam2. See the code listing below for a complete working function:
exports = function({ query, headers, body}, response) {
try {
if(body === undefined) {
throw new Error(`Request body was not defined.`)
}
const {queryStringParam1, queryStringParam2} = query;
console.log(queryStringParam1);
console.log(queryStringParam2);
console.log("contentTypes = " + headers["Content-Type"])
var bodyJson = EJSON.parse(body.text());
console.log(bodyJson);
var calculatedObject = new Object();
calculatedObject.queryStringParam1 = queryStringParam1;
calculatedObject.queryStringParam2 = queryStringParam2;
calculatedObject.requestPayloadFieldA = bodyJson.fieldA;
calculatedObject.requestPayloadFieldB = bodyJson.fieldB;
response.setStatusCode(200);
response.setBody(JSON.stringify(calculatedObject));
} catch (error) {
response.setStatusCode(400);
response.setBody(error.message);
console.log(error.message);
}
};
In this example, I simply repackage and reply with the same data as what was sent. The response payload combines query string variables and request payload variables into a single response payload.
Example of output:
barry#barry-laptop:~$ curl --include --verbose --header "Accept: application/json" --header "Content-Type: application/json" --request POST "https://eastus2.azure.data.mongodb-api.com/app/simplewebservice-ryzao/endpoint/test?queryStringParam1=abc&queryStringParam2=123" --data '{ "fieldA": { "$int": "1" }, "fieldB": {"$date": "2022-09-26T22:20:17.123Z" } }'
Note: Unnecessary use of -X or --request, POST is already inferred.
* Trying 20.71.94.254:443...
* Connected to eastus2.azure.data.mongodb-api.com (20.71.94.254) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* CAfile: /etc/ssl/certs/ca-certificates.crt
* CApath: /etc/ssl/certs
* TLSv1.0 (OUT), TLS header, Certificate Status (22):
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* TLSv1.2 (IN), TLS header, Certificate Status (22):
* TLSv1.3 (IN), TLS handshake, Server hello (2):
* TLSv1.2 (IN), TLS header, Finished (20):
* TLSv1.2 (IN), TLS header, Supplemental data (23):
* TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8):
* TLSv1.3 (IN), TLS handshake, Certificate (11):
* TLSv1.3 (IN), TLS handshake, CERT verify (15):
* TLSv1.3 (IN), TLS handshake, Finished (20):
* TLSv1.2 (OUT), TLS header, Finished (20):
* TLSv1.3 (OUT), TLS change cipher, Change cipher spec (1):
* TLSv1.2 (OUT), TLS header, Supplemental data (23):
* TLSv1.3 (OUT), TLS handshake, Finished (20):
* SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384
* ALPN, server accepted to use h2
* Server certificate:
* subject: CN=data.mongodb-api.com
* start date: Aug 8 12:45:54 2022 GMT
* expire date: Nov 6 12:45:53 2022 GMT
* subjectAltName: host "eastus2.azure.data.mongodb-api.com" matched cert's "eastus2.azure.data.mongodb-api.com"
* issuer: C=US; O=Let's Encrypt; CN=R3
* SSL certificate verify ok.
* Using HTTP2, server supports multiplexing
* Connection state changed (HTTP/2 confirmed)
* Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0
* TLSv1.2 (OUT), TLS header, Supplemental data (23):
* TLSv1.2 (OUT), TLS header, Supplemental data (23):
* TLSv1.2 (OUT), TLS header, Supplemental data (23):
* Using Stream ID: 1 (easy handle 0x56145e5b6e80)
* TLSv1.2 (OUT), TLS header, Supplemental data (23):
> POST /app/simplewebservice-ryzao/endpoint/test?queryStringParam1=abc&queryStringParam2=123 HTTP/2
> Host: eastus2.azure.data.mongodb-api.com
> user-agent: curl/7.81.0
> accept: application/json
> content-type: application/json
> content-length: 78
>
* TLSv1.2 (OUT), TLS header, Supplemental data (23):
* We are completely uploaded and fine
* TLSv1.2 (IN), TLS header, Supplemental data (23):
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* old SSL session ID is stale, removing
* TLSv1.2 (IN), TLS header, Supplemental data (23):
* Connection state changed (MAX_CONCURRENT_STREAMS == 2147483647)!
* TLSv1.2 (OUT), TLS header, Supplemental data (23):
* TLSv1.2 (IN), TLS header, Supplemental data (23):
< HTTP/2 200
HTTP/2 200
< vary: Origin
vary: Origin
< x-appservices-request-id: 633227f5d92f1e1d9c61bb7b
x-appservices-request-id: 633227f5d92f1e1d9c61bb7b
< x-frame-options: DENY
x-frame-options: DENY
< date: Mon, 26 Sep 2022 22:30:13 GMT
date: Mon, 26 Sep 2022 22:30:13 GMT
< content-length: 148
content-length: 148
< content-type: text/plain; charset=utf-8
content-type: text/plain; charset=utf-8
< server: envoy
server: envoy
<
* Connection #0 to host eastus2.azure.data.mongodb-api.com left intact
{"queryStringParam1":"abc","queryStringParam2":"123","requestPayloadFieldA":{"$int":"1"},"requestPayloadFieldB":{"$date":"2022-09-26T22:20:17.123Z"}}