Move 2021 conda packages from robotology to robotology-2021 channel

[traversaro]

In #1572 (comment) to unblock the generation of packages in the robotology channel, we decided to move the 2021 packages from robotology to robotology-2021 . I started last week with some manually download packages, we should complete this and document it.

[traversaro]

As we always increment the CONDA_BUILD_NUMBER at every build, we have a way to quickly spot 2021 builds: all builds till 37 has been done in 2021, while build 38 was the first in 2022.

[traversaro]

I am downloading all files with build_number <= 37 with:

import requests
import os
from tqdm import tqdm
from urllib.parse import urljoin

def download_packages(base_url):
    # Fetch package information from the URL
    repo_url = urljoin(base_url, "repodata.json")
    repo_data = requests.get(repo_url).json()
    packages_info = repo_data["packages"]

    # Download packages with build_number smaller than 37
    for package_name, package_info in packages_info.items():
        build_number = package_info.get("build_number", 0)
        if build_number <= 37:
            download_url = urljoin(base_url, package_name)
            file_size = package_info.get("size", 0)
            sha256_checksum = package_info.get("sha256", "")

            # Create a directory to store downloaded packages
            download_directory = "downloaded_packages"
            os.makedirs(download_directory, exist_ok=True)

            # Download the file
            response = requests.get(download_url, stream=True)
            file_path = os.path.join(download_directory, package_name)

            with open(file_path, "wb") as file, tqdm(
                desc=package_name,
                total=file_size,
                unit="B",
                unit_scale=True,
                unit_divisor=1024,
            ) as bar:
                for data in response.iter_content(chunk_size=1024):
                    bar.update(len(data))
                    file.write(data)

            # Verify SHA256 checksum if available
            if sha256_checksum:
                import hashlib

                sha256_hash = hashlib.sha256()
                with open(file_path, "rb") as file:
                    for chunk in iter(lambda: file.read(4096), b""):
                        sha256_hash.update(chunk)
                if sha256_hash.hexdigest() != sha256_checksum:
                    print(f"SHA256 checksum does not match for {package_name}.")
                else:
                    print(f"{package_name} downloaded successfully.")
            else:
                print(f"{package_name} downloaded successfully.")

# List of repository URLs
repository_urls = [
    "https://conda.anaconda.org/robotology/win-64/",
    "https://conda.anaconda.org/robotology/linux-64/",
    "https://conda.anaconda.org/robotology/osx-64/",
    "https://conda.anaconda.org/robotology/noarch/",
]

# Download packages from each repository
for repo_url in repository_urls:
    download_packages(repo_url)

[traversaro]

Probably we should migrate this packages to robotology on prefix.dev now?