refactor(gitlab): move all GitLab requests to dedicated client (#685)

Closes #676

reana_server/gitlab_client.py

@@ -0,0 +1,266 @@
+# This file is part of REANA.
+# Copyright (C) 2024 CERN.
+#
+# REANA is free software; you can redistribute it and/or modify it
+# under the terms of the MIT License; see LICENSE file for more details.
+"""REANA-Server GitLab client."""
+
+from typing import Dict, Optional, Union
+from urllib.parse import quote_plus
+import requests
+import yaml
+
+from reana_commons.k8s.secrets import REANAUserSecretsStore
+
+from reana_server.config import REANA_GITLAB_HOST
+
+
+class GitLabException(Exception):
+    """Base class for GitLab exceptions."""
+
+    def __init__(self, message):
+        """Initialise the GitLabException exception."""
+        self.message = message
+
+    def __str__(self):
+        """Return the exception message."""
+        return self.message
+
+
+class GitLabRequestError(GitLabException):
+    """Raised when a GitLab API request fails."""
+
+    def __init__(self, response, message=None):
+        """Initialise the GitLabRequestError exception."""
+        message = message or f"GitLab API request failed: {response.status_code}"
+        super().__init__(message)
+        self.response = response
+
+
+class InvalidGitLabTokenError(GitLabException):
+    """Raised when GitLab token is invalid or missing."""
+
+    def __init__(self, message=None):
+        """Initialise the InvalidGitLabTokenError exception."""
+        message = message or (
+            "GitLab token invalid or missing, "
+            "please go to your profile page on REANA "
+            "and reconnect to GitLab."
+        )
+        super().__init__(message)
+
+
+class GitLabClient:
+    """Client for interacting with the GitLab API."""
+
+    MAX_PER_PAGE = 100
+    """Maximum number of items per page in paginated responses."""
+
+    @classmethod
+    def from_k8s_secret(cls, user_id, **kwargs):
+        """
+        Create a client instance taking the GitLab token from the user's k8s secret.
+
+        :param user_id: User UUID.
+        """
+        secrets_store = REANAUserSecretsStore(str(user_id))
+        gitlab_token = secrets_store.get_secret_value("gitlab_access_token")
+        if not gitlab_token:
+            raise InvalidGitLabTokenError
+        return cls(access_token=gitlab_token, **kwargs)
+
+    def __init__(
+        self,
+        host: str = REANA_GITLAB_HOST,
+        access_token: Optional[str] = None,
+        http_request=None,
+    ):
+        """Initialise the GitLab client.
+
+        :param host: GitLab host (default: REANA_GITLAB_HOST)
+        :param access_token: GitLab access token (default: unauthenticated)
+        :param http_request: Function to make HTTP requests (default: requests.request).
+        """
+        self.access_token = access_token
+        self.host = host
+        self._http_request = (
+            http_request if http_request is not None else requests.request
+        )
+
+    def _make_url(self, path: str, **kwargs: Dict[str, str]):
+        quoted = {k: quote_plus(v) for k, v in kwargs.items()}
+        return f"https://{self.host}/api/v4/{path.lstrip('/').format(**quoted)}"
+
+    def _request(self, verb: str, url: str, params=None, data=None):
+        res = self._http_request(verb, url, params=params, data=data)
+        if res.status_code == 401:
+            raise InvalidGitLabTokenError
+        elif res.status_code >= 400:
+            message = f"GitLab API request failed: {res.status_code}, {res.content}"
+            try:
+                response = res.json()
+                if "message" in response:
+                    message = f"GitLab API request failed: {res.status_code}, {response['message']}"
+                elif "error_description" in response:
+                    message = f"GitLab API request failed: {res.status_code}, {response['error_description']}"
+            except Exception:
+                pass
+            raise GitLabRequestError(res, message)
+        return res
+
+    def _get(self, url, params=None):
+        return self._request("GET", url, params)
+
+    def _post(self, url, params=None, data=None):
+        return self._request("POST", url, params, data)
+
+    def _unroll_pagination(self, url, params):
+        # use maximum allowed value to avoid too many network requests
+        params["per_page"] = self.MAX_PER_PAGE
+        res = self._get(url, params)
+        while res:
+            yield from res.json()
+            next_url = res.links.get("next", {}).get("url")
+            res = self._get(next_url) if next_url else None
+
+    def oauth_token(self, data):
+        """Request an OAuth token from GitLab.
+
+        :param data: Dictionary with the following keys:
+            - client_id: The client ID of the application.
+            - client_secret: The client secret of the application.
+            - code: The authorization code.
+            - redirect_uri: The redirect URI of the application.
+            - grant_type: The grant type of the request.
+        """
+        # _make_url is not used here as the URL does not contain `api/v4`
+        url = f"https://{self.host}/oauth/token"
+        return self._post(url, data=data)
+
+    def get_file(
+        self, project: Union[int, str], file_path: str, ref: Optional[str] = None
+    ):
+        """Get the content of a file in a GitLab repository.
+
+        :param project: Project ID or name.
+        :param file_path: Path to the file.
+        :param ref: The name of a repository branch, tag or commit.
+        """
+        url = self._make_url(
+            "projects/{project}/repository/files/{file_path}/raw",
+            project=str(project),
+            file_path=file_path,
+        )
+        params = {
+            "access_token": self.access_token,
+            "ref": ref,
+        }
+        return self._get(url, params)
+
+    def get_projects(self, page: int = 1, per_page: Optional[int] = None, **kwargs):
+        """Get a list of projects the user has access to.
+
+        :param page: Page number.
+        :param per_page: Number of projects per page.
+        :param kwargs: Additional query parameters to customise and filter the results.
+        """
+        url = self._make_url("projects")
+        params = {
+            "access_token": self.access_token,
+            "page": page,
+            "per_page": per_page,
+            **kwargs,
+        }
+        return self._get(url, params)
+
+    def get_webhooks(
+        self, project: Union[int, str], page: int = 1, per_page: Optional[int] = None
+    ):
+        """Get a list of webhooks for a project.
+
+        :param project: Project ID or name.
+        :param page: Page number.
+        :param per_page: Number of webhooks per page.
+        """
+        url = self._make_url("projects/{project}/hooks", project=str(project))
+        params = {
+            "access_token": self.access_token,
+            "page": page,
+            "per_page": per_page,
+        }
+        return self._get(url, params)
+
+    def get_all_webhooks(self, project: Union[int, str]):
+        """Get all webhooks for a project.
+
+        Compared to `get_webhooks`, this method returns a generator that yields
+        all webhooks in the project, making multiple requests if necessary.
+
+        :param project: Project ID or name.
+        """
+        url = self._make_url("projects/{project}/hooks", project=str(project))
+        params = {"access_token": self.access_token}
+        yield from self._unroll_pagination(url, params)
+
+    def create_webhook(self, project: Union[int, str], config: Dict):
+        """Create a webhook for a project.
+
+        :param project: Project ID or name.
+        :param config: Dictionary withe the webhook configuration.
+            See https://docs.gitlab.com/ee/api/projects.html#add-project-hook
+        """
+        url = self._make_url("projects/{project}/hooks", project=str(project))
+        params = {"access_token": self.access_token}
+        return self._post(url, params, data=config)
+
+    def delete_webhook(self, project: Union[int, str], hook_id: int):
+        """Delete a webhook from a project.
+
+        :param project: Project ID or name.
+        :param hook_id: Webhook ID.
+        """
+        url = self._make_url(
+            "projects/{project}/hooks/{hook_id}",
+            project=str(project),
+            hook_id=str(hook_id),
+        )
+        params = {
+            "access_token": self.access_token,
+        }
+        return self._request("DELETE", url, params)
+
+    def set_commit_build_status(
+        self,
+        project: Union[int, str],
+        commit_sha: str,
+        state: str,
+        description: Optional[str] = None,
+        name: str = "reana",
+    ):
+        """Set the status of a commit in a GitLab repository.
+
+        :param project: Project ID or name.
+        :param commit_sha: The commit SHA.
+        :param state: The state of the status.
+            Can be one of 'pending', 'running', 'success', 'failed', 'canceled'.
+        :param description: A short description of the status.
+        :param name: The name of the context (default: 'reana').
+        """
+        url = self._make_url(
+            "projects/{project}/statuses/{commit_sha}",
+            project=str(project),
+            commit_sha=commit_sha,
+        )
+        params = {
+            "access_token": self.access_token,
+            "state": state,
+            "description": description,
+            "name": name,
+        }
+        return self._post(url, params)
+
+    def get_user(self):
+        """Get the user's profile."""
+        url = self._make_url("user")
+        params = {"access_token": self.access_token}
+        return self._get(url, params)