Apply a UDF

Jump to the Code block for a combined complete example.

UDFs that execute on a single record are Record UDFs. The record may or may not exist in the database, and the UDF may create, read, and/or update a record.

Setup

The following examples will use the setup below to illustrate applying a record UDF.

import (
    "fmt"
    "github.com/aerospike/aerospike-client-go/v6"
)

// Establishes a connection to the server
client, err := aerospike.NewClient("127.0.0.1", 3000)
if err != nil {
  log.Fatal(err)
}
defer client.Close()

The record structure:

Occurred: Integer
Reported: Integer
Posted: Integer
Report: Map
{
    shape: List,
    summary: String,
    city: String,
    state: String,
    duration: String
}
Location: GeoJSON

Single record commands

Single argument

This example uses the setRecent function in the module example.lua. See Manage UDFs for example.lua code and information on registering the UDF.

This compares the posted bin to a supplied value and writes true/false to a recent bin based on the result.

// Creates a key with the namespace "sandbox", set "ufodata", and user key 5000
key, err := aerospike.NewKey("sandbox", "ufodata", 5000)
if err != nil {
  log.Fatal(err)
}

// Execute the UDF
result, err := client.Execute(
    nil, key, "example", "setRecent", aerospike.NewValue(20210101))
if err != nil {
  log.Fatal(err)
}

// View the updated record
record, err := client.Get(nil, key)
if err != nil {
  log.Fatal(err)
}

fmt.Printf("Record: %v", record.Bins)

Multiple argument

This example uses the getDaysBetween function in the module example.lua. See Manage UDFs for example.lua code and information on registering the UDF.

This compares two dates, provived by passing the bin names with the date values, and returns the days between. The following example will return the days between the sighting occurence and posting to the site.

// Creates a key with the namespace "sandbox", set "ufodata", and user key 5000
key, err := aerospike.NewKey("sandbox", "ufodata", 5000)
if err != nil {
  log.Fatal(err)
}

// Execute the UDF
result, err := client.Execute(
    nil, key, "example", "getDaysBetween", aerospike.NewValue("occurred"), aerospike.NewValue("posted"))
if err != nil {
  log.Fatal(err)
}

// Do something
fmt.Printf("%v days between occurrence and post", result)

Batch operation with a UDF

This example will use the multi-argument example from above, and apply it to a batch of records.

// Create batch of keys
keys := make([]*aerospike.Key, 10)
for i := 0; i < 10; i++ {
    keys[i], err = aerospike.NewKey("sandbox", "ufodata", (i + 100))
    if err != nil {
     log.Fatal(err)
    }
}

// Execute the UDF
results, err := client.BatchExecute(
    nil, nil, keys, "example", "getDaysBetween", aerospike.NewValue("occurred"), aerospike.NewValue("posted"))
if err != nil {
  log.Fatal(err)
}

// Access the results
for _, result := range results {
    if result != nil {
        // Do something
        fmt.Printf("%v days between occurrence and post\\n", result.Record.Bins["SUCCESS"])
    }
}

Background query with a UDF

This example will use the single argument example from above, and apply it to all records that match a Filter Expression through a background query.

// Create new write policy
queryPolicy := aerospike.NewQueryPolicy()
queryPolicy.FilterExpression = aerospike.ExpBinExists("posted")

// Create statement
stmt := aerospike.NewStatement("sandbox", "ufodata")

task, err := client.ExecuteUDF(
    queryPolicy, stmt, "example", "setRecent", aerospike.NewValue(20210101))
if err != nil {
  log.Fatal(err)
}

// Return the query status
status, err := task.IsDone();
if err != nil {
    // Handle error
} else {
    if status {
        fmt.Printf("Query complete")
    } else {
        fmt.Printf("Query in progress")
    }
}

Code block

Expand this section for a single code block to apply a record UDF

import (
    "fmt"
    "github.com/aerospike/aerospike-client-go/v6"
)

func main() {
    // Establishes a connection to the server
    client, err := aerospike.NewClient("127.0.0.1", 3000)
    if err != nil {
        log.Fatal(err)
    }
    defer client.Close()

    // Creates a key with the namespace "sandbox", set "ufodata", and user key 5000
    key, err := aerospike.NewKey("sandbox", "ufodata", 5000)
    if err != nil {
        log.Fatal(err)
    }

    // Execute the UDF
    result, err := client.Execute(
        nil, key, "example", "getDaysBetween", aerospike.NewValue("occurred"), aerospike.NewValue("posted"))
    if err != nil {
        log.Fatal(err)
    }

    // Do something
    fmt.Printf("%v days between occurrence and post", result)
}