I'm posting this because I could not find any blog posts with sample code for video processing with AWS Lambda + AWS Elastic Transcoder in Golang.
Dependencies
- Golang v1.10
- aws/aws-lambda-go v1.1.0
- aws/aws-sdk-go v1.13.8
Premises
- You know AWS Lambda and Elastic Transcoder roughly
- You've already have a Elastic Transcoder Pipeline
- You know Golang a little and like it :)
Flow of the operations
- Upload a video file in a S3 bucket
- Lambda is trigger by 1. and create a Elastic Transcoder Job
That's it.
Implementation
Create a Lambda function
- Runtime:
Go 1.x - Set an appropriate Role (Elastic Transcoder access is required)
- Set a handler name as the same with the Go binary after
go build - Set a trigger as
S3and choose the Pipeline's input bucket name and event typeObjectCreated - Set your
PIPELINE_IDenvironment variable
Go code
package main
import (
"context"
"fmt"
"log"
"os"
"github.com/aws/aws-lambda-go/events"
"github.com/aws/aws-lambda-go/lambda"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/session"
transcoder "github.com/aws/aws-sdk-go/service/elastictranscoder"
)
var (
// Generic 720p
presetID = "1351620000001-000010"
)
func main() {
lambda.Start(handler)
}
func handler(ctx context.Context, s3Event events.S3Event) {
for _, record := range s3Event.Records {
s3 := record.S3
bucket := s3.Bucket.Name
objKey := s3.Object.Key
log.Printf("[%s - %s] Bucket = %s, Key = %s \n", record.EventSource, record.EventTime, bucket, objKey)
sess := session.Must(
session.NewSession(
&aws.Config{
// Set supported region
Region: aws.String("ap-northeast-1"),
},
),
)
svc := transcoder.New(sess)
resp, err := svc.CreateJob(
&transcoder.CreateJobInput{
Input: &transcoder.JobInput{
Key: aws.String(objKey),
},
Outputs: []*transcoder.CreateJobOutput{
&transcoder.CreateJobOutput{
PresetId: aws.String(presetID),
Key: aws.String(objKey),
// If the original filename is "test-file.mp4",
// this generates "test-file.mp4-00001.png"
ThumbnailPattern: aws.String(fmt.Sprintf("%s-{count}", objKey)),
},
},
PipelineId: aws.String(os.Getenv("PIPELINE_ID")),
},
)
if err != nil {
log.Printf("Failed: Create Job, %v\n", err)
return
}
log.Printf("Job Response: %v\n", resp.Job)
}
}
The structs options are at minimum, but you can set CreateJobOutput.ThumbnailPattern as "" if you don't want to generate thumbnails.
ThumbnailPattern must contain {count}.
aws.String(str) is the same with &str, you can use this as a shorthand.
strPtr := aws.String("somestring")
// the same with above, but you need to set a variable first.
str := "somestring"
strPtr := &str
Top comments (4)
@maestromac this might come in handy
Nice! I like how simple and straight forward your post is. Thank you for sharing!
Thank you! I hope this will help you :)
i want to add intervals between thumbnails. How can i do that with 'ThumbnailPattern' field ???... Or is there another way to do it ??