delta-s3-loader/src/lambda.rs

135 lines
3.9 KiB
Rust

use aws_lambda_events::event::s3::S3Event;
use lambda_runtime::{Context, Error};
use log::*;
/**
* The s3_event_handler will be invoked with an S3Event which will need to be iterated upon and
* each S3EventRecord processed:
* <https://docs.aws.amazon.com/lambda/latest/dg/with-s3.html>
*/
pub async fn s3_event_handler(event: S3Event, _ctx: Context) -> Result<String, Error> {
for record in event.records {
if let Some(ref name) = record.event_name {
trace!("Processing an event named: {}", name);
/*
* The only events that delta-s3-loader is interested in are new PUTs which
* indicate a new file must be processed.
*/
if name == "ObjectCreated:Put" {
trace!("Processing record: {:?}", record);
}
} else {
warn!("Received a record without a name: {:?}", record);
}
}
// Since this was triggered asynchronously, no need for a real response
Ok("{}".to_string())
}
/**
* A Partition is a simple struct to carry values from paths like:
* just/a/path/year=2021/mydata.json
*/
#[derive(Clone, Debug)]
struct Partition {
name: String,
value: String,
}
impl Partition {
/**
* Convert the given path string (e.g. root/year=2021/month=04/afile.json)
* into an ordered vector of the partitions contained within the path string
*/
fn from_path_str(pathstr: &str) -> Vec<Partition> {
pathstr
.split("/")
.filter_map(|part| {
let sides: Vec<&str> = part.split("=").collect();
if sides.len() == 2 {
Some(Partition {
name: sides[0].to_string(),
value: sides[1].to_string(),
})
} else {
None
}
})
.collect()
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn from_path_str_no_partitions() {
let result = Partition::from_path_str("just/a/path");
assert_eq!(0, result.len());
}
#[test]
fn from_path_str_single() {
let partitions = Partition::from_path_str("some/year=2021/file.json");
assert_eq!(1, partitions.len());
assert_eq!(partitions[0].name, "year");
assert_eq!(partitions[0].value, "2021");
}
fn sample_event() -> String {
String::from(
r#"
{
"Records": [
{
"eventVersion": "2.1",
"eventSource": "aws:s3",
"awsRegion": "us-east-2",
"eventTime": "2019-09-03T19:37:27.192Z",
"eventName": "ObjectCreated:Put",
"userIdentity": {
"principalId": "AWS:AIDAINPONIXQXHT3IKHL2"
},
"requestParameters": {
"sourceIPAddress": "205.255.255.255"
},
"responseElements": {
"x-amz-request-id": "D82B88E5F771F645",
"x-amz-id-2": "vlR7PnpV2Ce81l0PRw6jlUpck7Jo5ZsQjryTjKlc5aLWGVHPZLj5NeC6qMa0emYBDXOo6QBU0Wo="
},
"s3": {
"s3SchemaVersion": "1.0",
"configurationId": "828aa6fc-f7b5-4305-8584-487c791949c1",
"bucket": {
"name": "my-bucket",
"ownerIdentity": {
"principalId": "A3I5XTEXAMAI3E"
},
"arn": "arn:aws:s3:::lambda-artifacts-deafc19498e3f2df"
},
"object": {
"key": "somepath/date=2021-04-16/afile.json",
"size": 1305107,
"eTag": "b21b84d653bb07b05b1e6b33684dc11b",
"sequencer": "0C0F6F405D6ED209E1"
}
}
}
]
}"#,
)
}
#[tokio::test]
async fn test_s3_event_handler() {
let event: S3Event =
serde_json::from_str(&sample_event()).expect("Failed to deserialize event");
let result = s3_event_handler(event, Context::default())
.await
.expect("Failed to run event handler");
assert_eq!("{}", result);
}
}