Null pointer exception in ES painless script? - elasticsearch

Question

I am using painless script in ES and encountering a null pointer exception, here is my script and also I have added the response for better understanding, I use ES v7.3.
POST test_script/_update/1
{
"scripted_upsert": true,
"script": {
"lang": "painless",
"source": "int getBrowsersObjectIndex(def x, def y){for (int i = 0; i < x.length; i++) {if (x[i].deviceType == y.deviceType) {if (x[i].osName == y.osName) {if(x[i].browserName == y.browserName) {return i}}}}return -1} int getDevicesObjectIndex(def x, def y){for (int i = 0; i < x.length; i++) {if (x[i].deviceId == y.deviceId) {if (x[i].appName == y.appName) {if (x[i].appNameSpace == y.appNameSpace){return i}}}}return -1}if (!ctx._source.containsKey('browsers')) {ctx._source['browsers'] = []}if (!ctx._source.containsKey('devices')) {ctx._source['devices'] = []}for (int index = 0; index < params.iterate.length; index++) {if (params.iterate[index].browserObject) {int browserIndex = getBrowsersObjectIndex(ctx._source.browsers, params.iterate[index].browserObject);if (browserIndex >= 0) {ctx._source.browsers.remove(browserIndex);}ctx._source.browsers.add(params.iterate[index].browserObject);}if (params.iterate[index].deviceObject) {int deviceIndex = getDevicesObjectIndex(ctx._source.devices, params.iterate[index].deviceObject);if (deviceIndex >= 0) {ctx._source.devices.remove(deviceIndex);}ctx._source.devices.add(params.iterate[index].deviceObject);}}",
"params": {
"iterate": [
{
"deviceObject": {
"deviceId": "162c04e48832e338",
"appName": "test_app",
"appNameSpace": "com.test",
"appBuild": 55,
"appVersion": "4.6.3",
"deviceName": "OP4B80L1",
"manufacturer": "OPPO",
"model": "CPH1937",
"networkCarrier": "Jio",
"os": "Android",
"platform": "Android",
"timezone": "Asia/Kolkata",
"version": "10"
}
},
{
"browserObject": {
"deviceType": "mobile",
"osName": "Android",
"browserName": "Chrome",
"osVersion": 10,
"browserVersion": "80.0.3987.99"
}
}
]
}
},
"upsert": {}
}
Error is:
{
"error": {
"root_cause": [
{
"type": "remote_transport_exception",
"reason": "[connecto][192.168.36.235:9300][indices:data/write/update[s]]"
}
],
"type": "illegal_argument_exception",
"reason": "failed to execute script",
"caused_by": {
"type": "script_exception",
"reason": "runtime error",
"script_stack": [
"if (params.iterate[index].browserObject) {int ",
" ^---- HERE"
],
"script": "int getBrowsersObjectIndex(def x, def y){for (int i = 0; i < x.length; i++) {if (x[i].deviceType == y.deviceType) {if (x[i].osName == y.osName) {if(x[i].browserName == y.browserName) {return i}}}}return -1} int getDevicesObjectIndex(def x, def y){for (int i = 0; i < x.length; i++) {if (x[i].deviceId == y.deviceId) {if (x[i].appName == y.appName) {if (x[i].appNameSpace == y.appNameSpace){return i}}}}return -1}if (!ctx._source.containsKey('browsers')) {ctx._source['browsers'] = []}if (!ctx._source.containsKey('devices')) {ctx._source['devices'] = []}for (int index = 0; index < params.iterate.length; index++) {if (params.iterate[index].browserObject) {int browserIndex = getBrowsersObjectIndex(ctx._source.browsers, params.iterate[index].browserObject);if (browserIndex >= 0) {ctx._source.browsers.remove(browserIndex);}ctx._source.browsers.add(params.iterate[index].browserObject);}if (params.iterate[index].deviceObject) {int deviceIndex = getDevicesObjectIndex(ctx._source.devices, params.iterate[index].deviceObject);if (deviceIndex >= 0) {ctx._source.devices.remove(deviceIndex);}ctx._source.devices.add(params.iterate[index].deviceObject);}}",
"lang": "painless",
"caused_by": {
"type": "null_pointer_exception",
"reason": null
}
}
},
"status": 400
}
Seems like the error is in the if statement where I am checking if either of browserObject or deviceObject exists inside the iterate array of objects.

Answer 1

You need to perform an explicit null-check, i.e.
if (params.iterate[index].browserObject != null)
Besides, in Kibana Dev Tools, you can use triple quotes """ to properly format your code so it's more legible and easier to read/maintain:
POST test_script/_update/1
{
"scripted_upsert": true,
"script": {
"lang": "painless",
"source": """
int getBrowsersObjectIndex(def x, def y){
for (int i = 0; i < x.length; i++) {
if (x[i].deviceType == y.deviceType) {
if (x[i].osName == y.osName) {
if(x[i].browserName == y.browserName) {
return i
}
}
}
}
return -1
}
int getDevicesObjectIndex(def x, def y){
for (int i = 0; i < x.length; i++) {
if (x[i].deviceId == y.deviceId) {
if (x[i].appName == y.appName) {
if (x[i].appNameSpace == y.appNameSpace){
return i
}
}
}
}
return -1
}
if (!ctx._source.containsKey('browsers')) {
ctx._source['browsers'] = []
}
if (!ctx._source.containsKey('devices')) {
ctx._source['devices'] = []
}
for (int index = 0; index < params.iterate.length; index++) {
if (params.iterate[index].browserObject != null) {
int browserIndex = getBrowsersObjectIndex(ctx._source.browsers, params.iterate[index].browserObject);
if (browserIndex >= 0) {
ctx._source.browsers.remove(browserIndex);
}
ctx._source.browsers.add(params.iterate[index].browserObject);
}
if (params.iterate[index].deviceObject != null) {
int deviceIndex = getDevicesObjectIndex(ctx._source.devices, params.iterate[index].deviceObject);
if (deviceIndex >= 0) {
ctx._source.devices.remove(deviceIndex);
}
ctx._source.devices.add(params.iterate[index].deviceObject);
}
}
""",
"params": {
"iterate": [
{
"deviceObject": {
"deviceId": "162c04e48832e338",
"appName": "test_app",
"appNameSpace": "com.test",
"appBuild": 55,
"appVersion": "4.6.3",
"deviceName": "OP4B80L1",
"manufacturer": "OPPO",
"model": "CPH1937",
"networkCarrier": "Jio",
"os": "Android",
"platform": "Android",
"timezone": "Asia/Kolkata",
"version": "10"
}
},
{
"browserObject": {
"deviceType": "mobile",
"osName": "Android",
"browserName": "Chrome",
"osVersion": 10,
"browserVersion": "80.0.3987.99"
}
}
]
}
},
"upsert": {}
}