# 🔄 Execution Lifecycle in CCP

An **Execution** is the process of running a Method with user-provided inputs.  
It captures the full context, metadata, environment, and outputs of that run.

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## 📦 What Is an Execution?

An Execution is triggered when a user fills the form of a Method and runs it.  
This generates a full execution bundle that includes:

- Inputs and parameters
- Method descriptor
- Infrastructure and runtime details
- Output files
- Metadata and provenance

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## 🧬 Execution Data Structure

Each Execution is stored as a self-contained directory:

```
execution/
├── auth/
│   └── jwt.json                 # Authentication info
├── metadata/
│   ├── method.json              # Method used
│   ├── request.json             # Inputs and parameters
│   ├── infrastructure.json      # Runtime platform
│   ├── instance.json            # Runtime container details
│   ├── jobStatus.json           # Lifecycle status
│   └── provo.xml                # Provenance metadata
├── outputs/
│   ├── output_file1.txt         # User-generated files
│   ├── stdout.log / stderr.log  # Execution logs
└── output.zip                   # Archived version of all outputs
```

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## 🧪 How Executions Are Stored

Executions live in the user's **Workbench** (temporary area) and can be:

- **Re-executed** (same inputs)
- **Downloaded** (as `.zip`)
- **Shared** (via D4Science Workspace)
- **Archived** to workspace under `CCP/executions`

They can also be **imported back** into the Workbench using:

- A previously exported `.zip`
- A Workspace reference

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## 🚥 Execution Status

An Execution moves through these states:

1. **CREATED** →  initial request accepted
2. **SCHEDULED** → assigned to an infrastructure
3. **STARTED** → deploy-script begins
4. **EXECUTING** → main script running
5. **COMPLETED / FAILED** → terminal state

Each state is logged in `metadata_jobStatus.json`.

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## 📜 Metadata and Logging

CCP produces rich metadata for traceability:

- `provo.xml` for reproducibility and FAIR principles
- `stdout` / `stderr` logs
- JSON summaries of method, infra, inputs, and runtime

You can inspect them from the execution view or download them.

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## 🔗 Related Pages

- 🧱 [Platform architecture](/05_advanced_topics/01_architecture/01_platform_architecture.md)

- 🐳 [Runtime execution model](/05_advanced_topics/01_architecture/02_runtime_architecture.md)

- 📦 [Execution metadata](/03_execution/04_metadata_files.md)

- 🧬 [Provenance metadata (provo.xml)](/03_execution/05_metadata_provo.md)