Build Your First Pipeline

Create a simple log processing pipeline using the Expanso Cloud pipeline builder.

What You'll Build

A pipeline that:

1. Reads log files from your node
2. Filters for ERROR-level logs
3. Writes to STDOUT

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Step 1: Create a New Pipeline

1. In your workspace, go to the Pipelines tab
2. Click New Pipeline
3. On "How do you want to start?", choose Start from Scratch

This opens an empty pipeline in the visual builder.

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Step 2: Build the Pipeline

The builder opens in the Design view. Add and configure three components using their forms.

Input: File

1. Click + Add Input and select File
2. In the component form, add the path /var/log/*.log

This reads all .log files from /var/log/.

Processor: Mapping (uses Bloblang)

1. Click Add Processor and select Mapping
2. In the mapping field, enter:

   # Only keep ERROR logs
   root = if this.contains("ERROR") {
     this
   } else {
     deleted()
   }

Output: STDOUT

1. Click + Add Output and select STDOUT
2. In the component form, set the codec to lines

Your pipeline now shows File → Filter → STDOUT. Click Next.

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Step 3: Pipeline Details and Deploy

On the Pipeline Details step:

1. Enter a Name: error-log-filter (lowercase letters, numbers, and hyphens)
2. Under Node Selector, choose which nodes run the pipeline (leave it empty to target every node in the workspace, or match specific labels)
3. Click Create Pipeline

The pipeline deploys to the selected nodes within seconds.

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What's Next?

👉 View Results & Monitor

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Tips

Visual flow: Your pipeline shows: File → Filter → STDOUT

Edit anytime: Click the pipeline to edit and redeploy

Multiple outputs: Add more outputs to send data to multiple destinations

Learn Bloblang: See Bloblang Guide for advanced transformations