FastAPI

Warning

⚠️ Before we begin, please make sure that you have authentication covered.

Info

This example shows the general structure of how to build a FastAPI application with encord-agents. For concrete implementations of agents with specific abilities, please see the examples section.

Create a project

Create a new project:

mkdir my_project
cd my_project

Create and source a new virtual environment.

python -m venv venv
source venv/bin/activate

Install the dependencies.

python -m pip install "fastapi[standard]" encord-agents

Develop your agent

Create a main.py file with the following template:

main.py

from typing_extensions import Annotated

from encord.objects.ontology_labels_impl import LabelRowV2
from encord_agents import FrameData
from encord_agents.fastapi import dep_label_row

from fastapi import FastAPI, Depends, Form
from fastapi.middleware.cors import CORSMiddleware

app = FastAPI()
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*", "https://app.encord.com"],
)

@app.post("/my_agent")
def my_agent(
    frame_data: Annotated[FrameData, Form()],
    label_row: Annotated[LabelRowV2, Depends(dep_label_row)],
):
    # ... Do your edits to the labels
    label_row.save()

Fill in the function my_agent with what you want to happen when your agent is triggered.

Tip

💡 Notice that you can inject multiple different dependencies into the function if you want.

You can find multiple examples of what can be done with editor agents here.

Test the agent

First, run the agent locally, such that it can be triggered.

ENCORD_SSH_KEY_FILE=/path/to/your_private_key \
    fastapi dev main.py --port 8080

Info

Effectively, this means starting an API that lives at localhost:8080/my_agent and expects a POST request with JSON data of the following format:

{
    "project_hash": "<project_hash>",
    "data_hash": "<data_hash>",
    "frame": <frame_number>
}

To hit that agent endpoint, open the Label Editor in your browser on a frame for which you want to test your agent. Copy the URL.

Open a new terminal in the my_project directory. Then, run

source venv/bin/activate
encord-agents test local my_agent '<the_pasted_url>'

Warning

Notice the single quotes around <the_pasted_url>. They are important and should be there because you might copy a url with, e.g., an & character that have a special meaning if it is not within a string (or escaped).

Refresh the label editor in your browser to see the effect that you applied to the label_row: LabelRowV2 happening.

Deployment

Info

This section is under construction.

Meanwhile, please refer to the official FastAPI documentation.