func NewSaramaConsumers(servers []string, topic, offsetType string) (*sarama.Consumer, *[]sarama.PartitionConsumer, error) {
config := sarama.NewConfig()
config.ClientID = ipresolver.GetLocalAddr()
config.Consumer.Return.Errors = true
consumer, err := sarama.NewConsumer(servers, config)
if err != nil {
return nil, nil, err
}
partitions, err := consumer.Partitions(topic)
if err != nil {
return nil, nil, err
}
if eatonconfig.IsDebug() {
log.Println("Returned Partitions for topic: ", topic, partitions)
}
if len(partitions) == 0 {
return nil, nil, errors.New("no partitions returned to consume!")
}
partitionConsumers := make([]sarama.PartitionConsumer, len(partitions), len(partitions))
chosenOffset := sarama.OffsetOldest
switch offsetType {
case "oldest":
chosenOffset = sarama.OffsetOldest
break
case "newest":
chosenOffset = sarama.OffsetNewest
break
default:
log.Fatal("unknown offsetType provided: ", offsetType)
}
for index, partition := range partitions {
if eatonconfig.IsDebug() {
log.Println("Creating partition consumer for partition: ", partition, " with offset: ", chosenOffset)
}
partitionConsumer, err := consumer.ConsumePartition(topic, partition, chosenOffset)
if eatonconfig.IsDebug() {
log.Println("Created partition consumer: ", consumer)
}
if err != nil {
return nil, nil, err
}
if partitionConsumer == nil {
return nil, nil, errors.New("nil consumer returned!")
}
partitionConsumers[index] = partitionConsumer
}
return &consumer, &partitionConsumers, nil
}
func main() {
flag.StringVar(&S3BucketName, "bucket", "eaton-jobdescription-bucket", "the bucket to store retrieved indeed api messages from.")
flag.StringVar(&DynamoDBTableName, "table", "Documents", "the dynamodb table to store the indeed api messages.")
flag.StringVar(&logFile, "log", "eaton-feeder.log", "the log file to write results to.")
flag.StringVar(&AWSRegion, "region", "us-west-2", "the aws region to use when saving content to dynamodb and s3.")
flag.StringVar(&eatonconfig.OffsetType, "offset", "oldest", "the offset to use. either \"oldest\" or \"newest\" ")
flag.BoolVar(&doConsume, "consume", false, "set to true to consume messages from KAFKA_SERVERS and send them to S3/DynamoDB")
flag.BoolVar(&doProduce, "produce", false, "set to true to pull from the indeed api and push messages to KAFKA_SERVERS.")
flag.IntVar(&interval, "interval", -1, "the time between polls of the indeed api in millis. anything equal to or below 0 disables the interval function.")
flag.IntVar(&awsWorkPoolSize, "awsWorkPoolSize", 5, "the number of concurrent requests allowed when storing information in S3/DynamoDB")
flag.Parse()
log.Println("Using the following: ")
log.Println("\tbucket:\t", S3BucketName)
log.Println("\ttable:\t", DynamoDBTableName)
log.Println("\tlogFile:\t", logFile)
log.Println("\tregion:\t", AWSRegion)
log.Println("\toffset:\t", eatonconfig.OffsetType)
log.Println("\tconsume:\t", doConsume)
log.Println("\tproduce:\t", doProduce)
log.Println("\tinterval:\t", interval)
log.Println("\tawsWorkPoolSize\t", awsWorkPoolSize)
file, err := os.OpenFile(logFile, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
if err != nil {
log.Fatal("ERROR - failed to create log file: ", err)
}
defer file.Close()
log.SetOutput(file)
if !doProduce && !doConsume {
flag.PrintDefaults()
return
}
if doProduce && doConsume {
log.Fatal("ERROR - Cannot both produce and consume in a single application!")
}
err = eatonevents.Init()
if err != nil {
log.Fatal("ERROR - failed to create event publisher!")
}
var kafkaConsumer *IndeedKafkaConsumer
var kafkaProducer *IndeedKafkaProducer
if doProduce {
if eatonconfig.IsDebug() {
log.Println("Creating new IndeedKafkaProducer.")
}
indeedClient := new(IndeedClient)
indeedScraper := new(IndeedScraper)
kafkaProducer, err = NewKafkaProducer()
if err != nil {
eatonevents.Error("failed to create new kafka producer: ", err)
os.Exit(1)
}
errChannel, jobResultChannel := indeedClient.GetResults()
scraperErrChannel, scraperJobResultChannel := indeedScraper.GetFullJobSummary(jobResultChannel)
kafkaErrChannel, kafkaDoneChannel := kafkaProducer.SendMessages(scraperJobResultChannel)
go func() {
eatonevents.Debug("Waiting for messages from the indeedClient error channel...")
for err := range errChannel {
eatonevents.Error("IndeedClient: ", err)
}
eatonevents.Debug("Finished waiting on messages from the indeedClient error channel.")
}()
go func() {
eatonevents.Debug("Waiting on errors from the IndeedKafkaProducer error channel...")
for err := range kafkaErrChannel {
eatonevents.Error("IndeedKafkaProducer: ", err)
}
eatonevents.Debug("Finished waiting on messages from the IndeedKafkaProducer error channel.")
}()
go func() {
eatonevents.Debug("Waiting on errors from the IndeedScraper error channel...")
for err := range scraperErrChannel {
eatonevents.Error("IndeedScraper: ", err)
}
eatonevents.Debug("Finshed waiting on messages from the indeed scraper error channel.")
}()
for done := range kafkaDoneChannel {
eatonevents.Debug(fmt.Sprintf("completed sending messages to kafka (signal value: %d)", done))
if kafkaConsumer != nil {
kafkaConsumer.Close()
}
}
return
}
if doConsume {
eatonevents.Debug("Creating new IndeedKafkaConsumer.")
kafkaConsumer, err = NewKafkaConsumer()
if err != nil {
eatonevents.Error("failed to create new kafka consumer: ", err)
os.Exit(1)
}
errChannel := kafkaConsumer.ConsumeMessages()
for err := range errChannel {
eatonevents.Error("IndeedKafkaConsumer: ", err)
}
}
eatonevents.Info("Main function has completed. Exiting program.")
}