Dev Tools: Add Bacalhau (protocol#479)

Author: enoldev

content/en/curriculum/dev-tools/bacalhau/bacalhau-architecture.png

@@ -0,0 +1,77 @@
+---
+title: "Bacalhau"
+description: "A Computer Over Data Framework for IPFS"
+draft: false
+menu:
+  curriculum:
+    parent: "curriculum-devtools"
+category: lecture
+weight: 80
+level:
+- shallow
+- deep
+---
+
+Bacalhau is a framework that allows you to perform distributed computations on IPFS.
+These computations are executed in the form of Docker containers or WASM programs.
+
+The **Bacalhau network is a set of computers (nodes) working ready to perform computations**.
+You can send your computation (Docker container or WASM) to the Bacalhau network and then read the results.
+Every computation has an _input_ and an _output_.
+In Bacalhau, the main idea is that the **input is taken from IPFS, and the output is published to IPFS**.
+
+For example, consider that you have a Python script stored on IPFS, with CID `QmR1...`.
+This script prints numbers from 0 to 100, and you want to execute it on the Bacalhau network.
+
+![Bacalhau Overview](bacalhau-overview.png)
+
+First, you provide the CID of the Python script to the Bacalhau network.
+The script is fetched from IPFS, and is executed by one or several Bacalhau nodes.
+After the computation is finished, the results (the numbers printed) are published to IPFS, with a new CID, `QmFH...`.
+
+## Architecture
+
+Every node in the Bacalhau network can act as a _requester node_ or a _compute node_.
+Requester nodes are responsible for receiving the computations (in technical terms, called **jobs**) and delegating them to one or several compute nodes.
+Compute nodes are responsible for performing the actual computation.
+
+![Bacalhau High Level Architecture](bacalhau-architecture.png)
+
+The lifecycle of a job in Bacalhau is a complex task that includes several steps and verifications.
+You can read everything about the Bacalhau architecture in the [official documentation](https://docs.bacalhau.org/about-bacalhau/architecture).
+
+## The Bacalhau CLI
+
+Sending your computations and communicating with the Bacalhau network is pretty easy by using the Bacalhau CLI.
+The `bacalhau` command installed on your computer allows you to send a new job (computation), retrieve its status, or get its results.
+
+```bash
+> bacalhau docker run ubuntu echo Hello World
+```
+
+The previous command creates a new job in Bacalhau network by using a Docker image.
+Specifically, it runs an Ubuntu container and executes `echo Hello World` inside the container.
+
+You can then verify the status of the job by executing the following command.
+
+```bash
+> bacalhau list --id-filter=${JOB_ID}
+```
+
+If you are familiar with Docker, you should identify the `docker run` command, which allows you to execute Docker containers.
+The Bacalhau CLI adds several options on top of this command.
+
+```bash
+> bacalhau docker run \
+-v QmfKJT13h5k1b23ja3ZCVg5nFL9oKz2bVXc8oXgtwiwhjz:/files \
+ubuntu cat /files/read_csv.py
+```
+
+In the previous example, the command `cat /files/read_csv.py` is executed inside an Ubuntu container.
+The `-v` (volume) option allows you to mount an IPFS file or folder to a directory inside the Docker container.
+The IPFS folder with CID `QmfKJT13h5k1b23ja3ZCVg5nFL9oKz2bVXc8oXgtwiwhjz` is mounted to the `/files` directory inside the container. Therefore:
+1. An Ubuntu Docker container is created
+2. The `QmfKJT13h5k1b23ja3ZCVg5nFL9oKz2bVXc8oXgtwiwhjz` IPFS folder is mounted to the `/files` directory inside the container.
+3. The file is read by using the `cat` command.
+
+Now that you understand the basics of Bacalhau, check out the great examples in the [official documentation](https://docs.bacalhau.org/examples/).