Openflow 101: A 5-Step Crash Course for Data Engineers
The world of data engineering is constantly evolving, and Snowflake has just made its next major move. Introducing Snowflake Openflow, a data integration service built on the power and flexibility of Apache NiFi. If you’re a data engineer tasked with building robust, scalable data pipelines, this is a tool you need to know about.
Forget the days of managing complex NiFi clusters, wrestling with infrastructure, and patching open-source software. Openflow brings the visual, flow-based design paradigm of NiFi directly into the Snowflake ecosystem, allowing you to build everything from simple ingestion workflows to complex transformation pipelines with ease.
This crash course will walk you through everything you need to know to get started, using a simple 5-step approach.
The Big Picture – What Exactly is Openflow?
Think of Openflow as a sophisticated, automated assembly line for your data. In a factory, you have various stations (processors) that perform specific tasks, and a conveyor belt (connections) moves the product (data) from one station to the next.
At its core, Openflow is Snowflake’s managed offering of Apache NiFi. It provides a visual, drag-and-drop interface to design, deploy, and monitor data flows without writing extensive code. The key benefit is that it’s deeply integrated within the Snowflake Data Cloud, all under Snowflake’s unified security, governance, and billing model.
The Building Blocks – Processors
Processors are the workhorses of Openflow. Each one is a specialized tool that performs a specific task, such as fetching data, transforming it, routing it, or sending it to a destination. You can configure each processor’s properties to fine-tune its behavior.
Snowflake provides hundreds of processors (well over 200 today), and the catalogue keeps growing. Here are some of the most common ones you’ll use:
- Data Ingestion: GetFile, GetSFTP, GetHTTP, ListenHTTP, ConsumeKafkaRecord.
- Transformation: JoltTransformJSON (for complex JSON-to-JSON mapping), ReplaceText, UpdateAttribute, ConvertRecord.
- Routing & Filtering: RouteOnAttribute, RouteOnContent, ValidateRecord.
- Database Interaction: QueryDatabaseRecord, PutDatabaseRecord.
- Cloud Storage: PutS3Object, PutAzureDataLakeStorage, PutGCSObject.
- Execution: ExecuteScript, ExecuteProcess.
The Assembly Line – FlowFiles and Connections
How does data actually move through the system? Through two key components:
- FlowFiles: A FlowFile is the packet of data moving through your pipeline. It’s essentially a wrapper around your actual content (the data payload) and comes with attributes (key-value metadata). You might have an attribute for the source filename, a timestamp, or a database ID. Many processors work by reading, writing, or modifying these attributes.
- Connections: These are the conveyor belts that link your processors together, creating a directed graph. They act as queues, allowing FlowFiles to buffer between steps. This is crucial for handling backpressure: If a downstream system (like an API or database) slows down, FlowFiles will safely queue up in the connection, preventing data loss and allowing your pipeline to gracefully handle the bottleneck.
The Factory Floor – Understanding the Architecture
Openflow pipelines run in one of two deployment models:
- BYOC (Generally Available on AWS): Your runtimes live in your own VPC/EKS cluster, provisioned from Snowflake-supplied templates and managed from the Openflow control plane.
- Snowpark Container Services (SPCS) (Private Preview): A managed runtime where containers run inside Snowflake-managed infrastructure, eliminating the need for any cloud resources on your side.
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In the managed model, the factory floor is completely handled for you. Snowflake provisions and manages all necessary compute and storage.
In the BYOC model, while Snowflake manages the Openflow software, you are responsible for the underlying cloud infrastructure (like the EC2 instances in AWS). This gives you more control but also more responsibility—a key factor for our pro-tips below.
Regardless of the model, you get:
- Scalability on Demand: The architecture scales with your workload.
- Integrated Security: Openflow leverages Snowflake roles and permissions for access control.
- Unified Monitoring: Monitor your flows alongside your other Snowflake services.
Getting Data into Snowflake
Historically, you staged files and then called COPY INTO <params>, or you emitted row-by-row INSERTs yourself. Today, Openflow adds two native Snowflake processors alongside all the classics, so you can choose the pattern that matches your volume and latency needs.
Pattern 1 – Stage-and-Load (Batch)
Processor ➜ PutSnowflakeInternalStageFile
- GetSFTP (or GetFile, etc.) pulls partner files.
- Optional clean-up – UpdateAttribute, ConvertRecord for standardisation.
- PutSnowflakeInternalStageFile streams each file to an internal stage and automatically triggers the load.
- PutIcebergTable Store records in Iceberg using configurable Catalog for managing namespaces and tables.
Uses: Nightly/weekly drops, 10 MB → multi-GB files, or any case where throughput matters more than sub-second latency.
Pattern 2 – Firehose Streaming (Sub-second)
Processor ➜ PutSnowpipeStreaming
- ConsumeKafkaRecord (or ListenHTTP) ingests individual events.
- Optional transform – JoltTransformJSON.
- PutSnowpipeStreaming batches rows in-memory and commits via the Snowpipe Streaming API with exactly-once guarantees.
Uses: IoT/CDC workloads where you need seconds-level latency at hundreds-of-thousands of rows per second.
Pattern 3 – DIY COPY INTO (Traditional)
Processors ➜ PutS3Object + ExecuteScript (COPY INTO)
Uses: Still perfectly valid when you already have an external stage and want maximum control over your COPY options.
Pro-Tips for Lean Testing & Rapid Troubleshooting
Once you’ve grasped the basics, the next step is to work efficiently. These tips are essential for creating a professional development and testing workflow.
Tip 1 (For BYOC Deployments): Enforce a Minimalist Footprint for Testing.
A default Openflow deployment is built for production scale, but for development, you need speed, predictability, and cost control.
- The Goal: Create a deterministic environment that is fast, clean, and easy to reason about.
- The Action: In the AWS Console, navigate to EC2 → Auto Scaling Groups. Pin your development environment to the absolute minimum needed:
- Set the mgmt and runtime-small groups to Min: 1, Desired: 1, Max: 1.
- Set all other runtime groups (medium, large, etc.) to Min: 0, Desired: 0, Max: 0.
** ASG names follow the pattern runtime-<size> and mgmt-<version> in current templates; confirm the exact names in the AWS console before pinning min/desired/max.
The Benefit: Your dev environment becomes stable and lightweight. This accelerates deployment cycles, reduces costs, and ensures your tests are repeatable by removing the variable of a large, fluctuating cluster.
Tip 2 (For All Deployments): Isolate and Test on the Canvas.
Before you even think about production data, validate each step of your logic individually.
- Isolate and Run: Right-click any processor and select “Run once”. This executes a single cycle, letting you control the flow of data precisely.
- Inspect the Output: After the processor runs, right-click the outbound connection and select “List queue”.
- Examine the Details: From the queue viewer, you can inspect the FlowFile’s attributes and content. This step-by-step validation is the fastest way to confirm your logic.
Tip 3 (For All Deployments): Troubleshoot with SQL, Not with grep.
When a flow fails in a live environment, find the root cause — fast. Use Snowflake’s query power to find the exact error signal instantly. This is the single most powerful advantage of having your integration tool inside the Data Cloud.
- The Goal: Reduce your Mean Time To Resolution (MTTR) by turning the log firehose into a high-fidelity signal.
- The Action: Snowflake automatically centralizes telemetry data into the openflow.telemetry.EVENTS table. Keep the following SQL query in a saved Snowsight worksheet. When an issue arises, run it to get an immediate, structured view of only the actual exceptions that have occurred in your runtime.
Use this query to understand the actual exceptions:
WITH ParsedLogs AS (
SELECT
timestamp AS event_ingest_timestamp,
RESOURCE_ATTRIBUTES:"k8s.namespace.name"::STRING AS Namespace,
RESOURCE_ATTRIBUTES:"k8s.pod.name"::STRING AS Pod,
RESOURCE_ATTRIBUTES:"k8s.container.name"::STRING AS Container,
TRY_PARSE_JSON(value::STRING) AS json_log_data,
value AS raw_log_value
FROM openflow.telemetry.EVENTS
WHERE true
AND record_type = 'LOG'
AND timestamp > DATEADD(hour, -24, SYSDATE()) -- Time filter on ingest timestamp
AND RESOURCE_ATTRIBUTES:"k8s.namespace.name"::STRING LIKE 'runtime-%'
AND RESOURCE_ATTRIBUTES:"k8s.container.name"::STRING LIKE '%-server'
)
SELECT
p.event_ingest_timestamp,
p.Namespace,
p.Pod,
p.Container,
p.json_log_data:"timestamp"::BIGINT AS log_source_timestamp_ms,
p.json_log_data:"level"::STRING AS log_level,
p.json_log_data:"threadName"::STRING AS log_thread_name,
p.json_log_data:"loggerName"::STRING AS log_logger_name,
p.json_log_data:"formattedMessage"::STRING AS log_message,
p.json_log_data:"throwable"::VARIANT AS log_throwable,
p.raw_log_value
FROM ParsedLogs p
WHERE LOG_THROWABLE != 'null'
ORDER BY p.event_ingest_timestamp DESC;
The Benefit: This query is your precision diagnostic tool. It takes you directly to the stack trace without any guesswork, turning Snowflake from just a data destination into a core part of your observability toolkit.
Your Next Steps
You now have the foundational knowledge to start exploring Snowflake Openflow. The best way to learn is by doing. Open your Snowflake UI, navigate to the Data Integration section, and start building. Recreate the simple ingest flow described above. With a visual interface and the operational burden lifted, you can focus on what truly matters: delivering reliable, timely data to your organization.

