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Version: 0.14.0

Assertions

This guide specifically covers how to use the Assertion APIs for DataHub Cloud native assertions, including:

Why Would You Use Assertions APIs?

The Assertions APIs allow you to create, schedule, run, and delete Assertions with DataHub Cloud.

Goal Of This Guide

This guide will show you how to create, schedule, run and delete Assertions for a Table.

Prerequisites

The actor making API calls must have the Edit Assertions and Edit Monitors privileges for the Tables at hand.

Create Assertions

You can create new dataset Assertions to DataHub using the following APIs.

Freshness Assertion

To create a new freshness assertion, use the upsertDatasetFreshnessAssertionMonitor GraphQL Mutation.

mutation upsertDatasetFreshnessAssertionMonitor {
upsertDatasetFreshnessAssertionMonitor(
input: {
entityUrn: "<urn of entity being monitored>",
schedule: {
type: FIXED_INTERVAL,
fixedInterval: { unit: HOUR, multiple: 8 }
}
evaluationSchedule: {
timezone: "America/Los_Angeles",
cron: "0 */8 * * *"
}
evaluationParameters: {
sourceType: INFORMATION_SCHEMA
}
mode: ACTIVE
}
) {
urn
}
}

This API will return a unique identifier (URN) for the new assertion if you were successful:

{
"data": {
"upsertDatasetFreshnessAssertionMonitor": {
"urn": "urn:li:assertion:your-new-assertion-id"
}
},
"extensions": {}
}

For more details, see the Freshness Assertions guide.

Volume Assertions

To create a new volume assertion, use the upsertDatasetVolumeAssertionMonitor GraphQL Mutation.

mutation upsertDatasetVolumeAssertionMonitor {
upsertDatasetVolumeAssertionMonitor(
input: {
entityUrn: "<urn of entity being monitored>"
type: ROW_COUNT_TOTAL
rowCountTotal: {
operator: BETWEEN
parameters: {
minValue: {
value: "10"
type: NUMBER
}
maxValue: {
value: "20"
type: NUMBER
}
}
}
evaluationSchedule: {
timezone: "America/Los_Angeles"
cron: "0 */8 * * *"
}
evaluationParameters: {
sourceType: INFORMATION_SCHEMA
}
mode: ACTIVE
}
) {
urn
}
}

This API will return a unique identifier (URN) for the new assertion if you were successful:

{
"data": {
"upsertDatasetVolumeAssertionMonitor": {
"urn": "urn:li:assertion:your-new-assertion-id"
}
},
"extensions": {}
}

For more details, see the Volume Assertions guide.

Column Assertions

To create a new column assertion, use the upsertDatasetFieldAssertionMonitor GraphQL Mutation.

mutation upsertDatasetFieldAssertionMonitor {
upsertDatasetFieldAssertionMonitor(
input: {
entityUrn: "<urn of entity being monitored>"
type: FIELD_VALUES,
fieldValuesAssertion: {
field: {
path: "<name of the column to be monitored>",
type: "NUMBER",
nativeType: "NUMBER(38,0)"
},
operator: GREATER_THAN,
parameters: {
value: {
type: NUMBER,
value: "10"
}
},
failThreshold: {
type: COUNT,
value: 0
},
excludeNulls: true
}
evaluationSchedule: {
timezone: "America/Los_Angeles"
cron: "0 */8 * * *"
}
evaluationParameters: {
sourceType: ALL_ROWS_QUERY
}
mode: ACTIVE
}
){
urn
}
}

This API will return a unique identifier (URN) for the new assertion if you were successful:

{
"data": {
"upsertDatasetFieldAssertionMonitor": {
"urn": "urn:li:assertion:your-new-assertion-id"
}
},
"extensions": {}
}

For more details, see the Column Assertions guide.

Custom SQL Assertions

To create a new column assertion, use the upsertDatasetSqlAssertionMonitor GraphQL Mutation.

mutation upsertDatasetSqlAssertionMonitor {
upsertDatasetSqlAssertionMonitor(
assertionUrn: "<urn of assertion created in earlier query>"
input: {
entityUrn: "<urn of entity being monitored>"
type: METRIC,
description: "<description of the custom assertion>",
statement: "<SQL query to be evaluated>",
operator: GREATER_THAN_OR_EQUAL_TO,
parameters: {
value: {
value: "100",
type: NUMBER
}
}
evaluationSchedule: {
timezone: "America/Los_Angeles"
cron: "0 */6 * * *"
}
mode: ACTIVE
}
) {
urn
}
}

This API will return a unique identifier (URN) for the new assertion if you were successful:

{
"data": {
"upsertDatasetSqlAssertionMonitor": {
"urn": "urn:li:assertion:your-new-assertion-id"
}
},
"extensions": {}
}

For more details, see the Custom SQL Assertions guide.

Schema Assertions

To create a new schema assertion, use the upsertDatasetSchemaAssertionMonitor GraphQL Mutation.

mutation upsertDatasetSchemaAssertionMonitor {
upsertDatasetSchemaAssertionMonitor(
assertionUrn: "urn:li:assertion:existing-assertion-id",
input: {
entityUrn: "<urn of the table to be monitored>",
assertion: {
compatibility: EXACT_MATCH,
fields: [
{
path: "id",
type: STRING
},
{
path: "count",
type: NUMBER
},
{
path: "struct",
type: STRUCT
},
{
path: "struct.nestedBooleanField",
type: BOOLEAN
}
]
},
description: "<description of the schema assertion>",
mode: ACTIVE
}
)
}

This API will return a unique identifier (URN) for the new assertion if you were successful:

{
"data": {
"upsertDatasetSchemaAssertionMonitor": {
"urn": "urn:li:assertion:your-new-assertion-id"
}
},
"extensions": {}
}

For more details, see the Schema Assertions guide.

Run Assertions

You can use the following APIs to trigger the assertions you've created to run on-demand. This is particularly useful for running assertions on a custom schedule, for example from your production data pipelines.

Long-Running Assertions: The timeout for synchronously running an assertion is currently limited to a maximum of 30 seconds. Each of the following APIs support an async parameter, which can be set to true to run the assertion asynchronously. When set to true, the API will kick off the assertion run and return null immediately. To view the result of the assertion, simply fetching the runEvents field of the assertion(urn: String!) GraphQL query.

Run Assertion

mutation runAssertion {
runAssertion(urn: "urn:li:assertion:your-assertion-id", saveResult: true) {
type
nativeResults {
key
value
}
}
}

Where type will contain the Result of the assertion run, either SUCCESS, FAILURE, or ERROR.

The saveResult argument determines whether the result of the assertion will be saved to DataHub's backend, and available to view through the DataHub UI. If this is set to false, the result will NOT be stored in DataHub's backend. The value defaults to true.

If the assertion is external (not natively executed by Acryl), this API will return an error.

If running the assertion is successful, the result will be returned as follows:

{
"data": {
"runAssertion": {
"type": "SUCCESS",
"nativeResults": [
{
"key": "Value",
"value": "1382"
}
]
}
},
"extensions": {}
}

Run Group of Assertions

mutation runAssertions {
runAssertions(urns: ["urn:li:assertion:your-assertion-id-1", "urn:li:assertion:your-assertion-id-2"], saveResults: true) {
passingCount
failingCount
errorCount
results {
urn
result {
type
nativeResults {
key
value
}
}
}
}
}

Where type will contain the Result of the assertion run, either SUCCESS, FAILURE, or ERROR.

The saveResults argument determines whether the result of the assertion will be saved to DataHub's backend, and available to view through the DataHub UI. If this is set to false, the result will NOT be stored in DataHub's backend. The value defaults to true.

If any of the assertion are external (not natively executed by Acryl), they will simply be omitted from the result set.

If running the assertions is successful, the results will be returned as follows:

{
"data": {
"runAssertions": {
"passingCount": 2,
"failingCount": 0,
"errorCount": 0,
"results": [
{
"urn": "urn:li:assertion:your-assertion-id-1",
"result": {
"type": "SUCCESS",
"nativeResults": [
{
"key": "Value",
"value": "1382"
}
]
}
},
{
"urn": "urn:li:assertion:your-assertion-id-2",
"result": {
"type": "FAILURE",
"nativeResults": [
{
"key": "Value",
"value": "12323"
}
]
}
}
]
}
},
"extensions": {}
}

Where you should see one result object for each assertion.

Run All Assertions for Table

You can also run all assertions for a specific data asset using the runAssertionsForAsset mutation.

mutation runAssertionsForAsset {
runAssertionsForAsset(urn: "urn:li:dataset:(urn:li:dataPlatform:snowflake,purchase_events,PROD)", saveResults: true) {
passingCount
failingCount
errorCount
results {
urn
result {
type
nativeResults {
key
value
}
}
}
}
}

Where type will contain the Result of the assertion run, either SUCCESS, FAILURE, or ERROR.

The saveResults argument determines whether the result of the assertion will be saved to DataHub's backend, and available to view through the DataHub UI. If this is set to false, the result will NOT be stored in DataHub's backend. The value defaults to true.

If any of the assertion are external (not natively executed by Acryl), they will simply be omitted from the result set.

If running the assertions is successful, the results will be returned as follows:

{
"data": {
"runAssertionsForAsset": {
"passingCount": 2,
"failingCount": 0,
"errorCount": 0,
"results": [
{
"urn": "urn:li:assertion:your-assertion-id-1",
"result": {
"type": "SUCCESS",
"nativeResults": [
{
"key": "Value",
"value": "1382"
}
]
}
},
{
"urn": "urn:li:assertion:your-assertion-id-2",
"result": {
"type": "FAILURE",
"nativeResults": [
{
"key": "Value",
"value": "12323"
}
]
}
}
]
}
},
"extensions": {}
}

Where you should see one result object for each assertion.

Run Group of Assertions for Table

If you don't always want to run all assertions for a given table, you can also opt to run a subset of the table's assertions using Assertion Tags. First, you'll add tags to your assertions to group and categorize them, then you'll call the runAssertionsForAsset mutation with the tagUrns argument to filter for assertions having those tags.

Step 1: Adding Tag to an Assertion

Currently, you can add tags to an assertion only via the DataHub GraphQL API. You can do this using the following mutation:

mutation addTags {
addTag(input: {
resourceUrn: "urn:li:assertion:your-assertion",
tagUrn: "urn:li:tag:my-important-tag",
})
}

Step 2: Run All Assertions for a Table with Tags

Now, you can run all assertions for a table with a specific tag(s) using the runAssertionsForAsset mutation with the tagUrns input parameter:

mutation runAssertionsForAsset {
runAssertionsForAsset(urn: "urn:li:dataset:(urn:li:dataPlatform:snowflake,purchase_events,PROD)", tagUrns: ["urn:li:tag:my-important-tag"]) {
passingCount
failingCount
errorCount
results {
urn
result {
type
nativeResults {
key
value
}
}
}
}
}

Coming Soon: Support for adding tags to assertions through the DataHub UI.

Experimental: Providing Dynamic Parameters to Assertions

You can provide dynamic parameters to your assertions to customize their behavior. This is particularly useful for assertions that require dynamic parameters, such as a threshold value that changes based on the time of day.

Dynamic parameters can be injected into the SQL fragment portion of any Assertion. For example, it can appear in any part of the SQL statement in a Custom SQL Assertion, or it can appear in the Advanced > Filter section of a Column, Volume, or Freshness Assertion.

To do so, you'll first need to edit the SQL fragment to include the dynamic parameter. Dynamic parameters appear as ${parameterName} in the SQL fragment.

Next, you'll call the runAssertion, runAssertions, or runAssertionsForAsset mutations with the parameters input argument. This argument is a list of key-value tuples, where the key is the parameter name and the value is the parameter value:

mutation runAssertion {
runAssertion(urn: "urn:li:assertion:your-assertion-id", parameters: [{key: "parameterName", value: "parameterValue"}]) {
type
nativeResults {
key
value
}
}
}

At runtime, the ${parameterName} placeholder in the SQL fragment will be replaced with the provided parameterValue before the query is sent to the database for execution.

Get Assertion Details

You can use the following APIs to

  1. Fetch existing assertion definitions + run history
  2. Fetch the assertions associated with a given table + their run history.

Get Assertions for Table

To retrieve all the assertions for a table, you can use the following GraphQL Query.

query dataset {
dataset(urn: "urn:li:dataset:(urn:li:dataPlatform:snowflake,purchases,PROD)") {
assertions(start: 0, count: 1000) {
start
count
total
assertions {
urn
# Fetch the last run of each associated assertion.
runEvents(status: COMPLETE, limit: 1) {
total
failed
succeeded
runEvents {
timestampMillis
status
result {
type
nativeResults {
key
value
}
}
}
}
info {
type
description
lastUpdated {
time
actor
}
datasetAssertion {
datasetUrn
scope
aggregation
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
fields {
urn
path
}
nativeType
nativeParameters {
key
value
}
logic
}
freshnessAssertion {
type
entityUrn
schedule {
type
cron {
cron
timezone
}
fixedInterval {
unit
multiple
}
}
filter {
type
sql
}
}
sqlAssertion {
type
entityUrn
statement
changeType
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
}
fieldAssertion {
type
entityUrn
filter {
type
sql
}
fieldValuesAssertion {
field {
path
type
nativeType
}
transform {
type
}
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
failThreshold {
type
value
}
excludeNulls
}
fieldMetricAssertion {
field {
path
type
nativeType
}
metric
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
}
}
volumeAssertion {
type
entityUrn
filter {
type
sql
}
rowCountTotal {
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
}
rowCountChange {
type
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
}
}
schemaAssertion {
entityUrn
compatibility
fields {
path
type
nativeType
}
schema {
fields {
fieldPath
type
nativeDataType
}
}
}
source {
type
created {
time
actor
}
}
}
}
}
}
}

Get Assertion Details

You can use the following GraphQL query to fetch the details for an assertion along with its evaluation history by URN.

query getAssertion {
assertion(urn: "urn:li:assertion:assertion-id") {
urn
# Fetch the last 10 runs for the assertion.
runEvents(status: COMPLETE, limit: 10) {
total
failed
succeeded
runEvents {
timestampMillis
status
result {
type
nativeResults {
key
value
}
}
}
}
info {
type
description
lastUpdated {
time
actor
}
datasetAssertion {
datasetUrn
scope
aggregation
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
fields {
urn
path
}
nativeType
nativeParameters {
key
value
}
logic
}
freshnessAssertion {
type
entityUrn
schedule {
type
cron {
cron
timezone
}
fixedInterval {
unit
multiple
}
}
filter {
type
sql
}
}
sqlAssertion {
type
entityUrn
statement
changeType
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
}
fieldAssertion {
type
entityUrn
filter {
type
sql
}
fieldValuesAssertion {
field {
path
type
nativeType
}
transform {
type
}
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
failThreshold {
type
value
}
excludeNulls
}
fieldMetricAssertion {
field {
path
type
nativeType
}
metric
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
}
}
volumeAssertion {
type
entityUrn
filter {
type
sql
}
rowCountTotal {
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
}
rowCountChange {
type
operator
parameters {
value {
value
type
}
minValue {
value
type
}
maxValue {
value
type
}
}
}
}
schemaAssertion {
entityUrn
compatibility
fields {
path
type
nativeType
}
schema {
fields {
fieldPath
type
nativeDataType
}
}
}
source {
type
created {
time
actor
}
}
}
}
}

Add Tag to Assertion

You can add tags to individual assertions to group and categorize them, for example by its priority or severity. Note that the tag should already exist in DataHub, or the operation will fail.

mutation addTags {
addTag(input: {
resourceUrn: "urn:li:assertion:your-assertion",
tagUrn: "urn:li:tag:my-important-tag",
})
}

If you see the following response, the operation was successful:

{
"data": {
"addTag": true
},
"extensions": {}
}

You can create new tags using the createTag mutation or via the UI.

Delete Assertions

You can use delete dataset operations to DataHub using the following APIs.

mutation deleteAssertion {
deleteAssertion(urn: "urn:li:assertion:test")
}

If you see the following response, the operation was successful:

{
"data": {
"deleteAssertion": true
},
"extensions": {}
}

(Advanced) Create and Report Results for Custom Assertions

If you'd like to create and report results for your own custom assertions, e.g. those which are run and evaluated outside of Acryl, you need to generate 2 important Assertion Entity aspects, and give the assertion a unique URN of the following format:

  1. Generate a unique URN for your assertion
urn:li:assertion:<unique-assertion-id>
  1. Generate the AssertionInfo aspect for the assertion. You can do this using the Python SDK. Give your assertion a type and a source with type EXTERNAL to mark it as an external assertion, not run by DataHub itself.

  2. Generate the AssertionRunEvent timeseries aspect using the Python SDK. This aspect should contain the result of the assertion run at a given timestamp and will be shown on the results graph in DataHub's UI.