random operations test (#10986)

## Problem
We need to test the stability of Neon.

## Summary of changes
The test runs random operations on a Neon project. It performs via the
Public API calls the following operations: `create a branch`, `delete a
branch`, `add a read-only endpoint`, `delete a read-only endpoint`,
`restore a branch to a random position in the past`. All the branches
and endpoints are loaded with `pgbench`.

---------

Co-authored-by: Peter Bendel <peterbendel@neon.tech>
Co-authored-by: Alexander Bayandin <alexander@neon.tech>

test_runner/fixtures/neon_api.py

@@ -22,19 +22,62 @@ def connection_parameters_to_env(params: dict[str, str]) -> dict[str, str]:
     }
 
 
+# Some API calls not yet implemented.
+# You may want to copy not-yet-implemented methods from the PR https://github.com/neondatabase/neon/pull/11305
 class NeonAPI:
     def __init__(self, neon_api_key: str, neon_api_base_url: str):
         self.__neon_api_key = neon_api_key
         self.__neon_api_base_url = neon_api_base_url.strip("/")
+        self.retry_if_possible = False
+        self.attempts = 10
+        self.sleep_before_retry = 1
+        self.retries524 = 0
+        self.retries4xx = 0
 
     def __request(self, method: str | bytes, endpoint: str, **kwargs: Any) -> requests.Response:
-        if "headers" not in kwargs:
-            kwargs["headers"] = {}
+        kwargs["headers"] = kwargs.get("headers", {})
         kwargs["headers"]["Authorization"] = f"Bearer {self.__neon_api_key}"
 
-        resp = requests.request(method, f"{self.__neon_api_base_url}{endpoint}", **kwargs)
-        log.debug("%s %s returned a %d: %s", method, endpoint, resp.status_code, resp.text)
-        resp.raise_for_status()
+        for attempt in range(self.attempts):
+            retry = False
+            resp = requests.request(method, f"{self.__neon_api_base_url}{endpoint}", **kwargs)
+            if resp.status_code >= 400:
+                log.error(
+                    "%s %s returned a %d: %s",
+                    method,
+                    endpoint,
+                    resp.status_code,
+                    resp.text if resp.status_code != 524 else "CloudFlare error page",
+                )
+            else:
+                log.debug("%s %s returned a %d: %s", method, endpoint, resp.status_code, resp.text)
+            if not self.retry_if_possible:
+                resp.raise_for_status()
+                break
+            elif resp.status_code >= 400:
+                if resp.status_code == 422:
+                    if resp.json()["message"] == "branch not ready yet":
+                        retry = True
+                        self.retries4xx += 1
+                elif resp.status_code == 423 and resp.json()["message"] in {
+                    "endpoint is in some transitive state, could not suspend",
+                    "project already has running conflicting operations, scheduling of new ones is prohibited",
+                }:
+                    retry = True
+                    self.retries4xx += 1
+                elif resp.status_code == 524:
+                    log.info("The request was timed out, trying to get operations")
+                    retry = True
+                    self.retries524 += 1
+            if retry:
+                log.info("Retrying, attempt %s/%s", attempt + 1, self.attempts)
+                time.sleep(self.sleep_before_retry)
+                continue
+            else:
+                resp.raise_for_status()
+            break
+        else:
+            raise RuntimeError("Max retry count is reached")
 
         return resp
 
@@ -101,6 +144,96 @@ class NeonAPI:
 
         return cast("dict[str, Any]", resp.json())
 
+    def create_branch(
+        self,
+        project_id: str,
+        branch_name: str | None = None,
+        parent_id: str | None = None,
+        parent_lsn: str | None = None,
+        parent_timestamp: str | None = None,
+        protected: bool | None = None,
+        archived: bool | None = None,
+        init_source: str | None = None,
+        add_endpoint=True,
+    ) -> dict[str, Any]:
+        data: dict[str, Any] = {}
+        if add_endpoint:
+            data["endpoints"] = [{"type": "read_write"}]
+        data["branch"] = {}
+        if parent_id:
+            data["branch"]["parent_id"] = parent_id
+        if branch_name:
+            data["branch"]["name"] = branch_name
+        if parent_lsn is not None:
+            data["branch"]["parent_lsn"] = parent_lsn
+        if parent_timestamp is not None:
+            data["branch"]["parent_timestamp"] = parent_timestamp
+        if protected is not None:
+            data["branch"]["protected"] = protected
+        if init_source is not None:
+            data["branch"]["init_source"] = init_source
+        if archived is not None:
+            data["branch"]["archived"] = archived
+        if not data["branch"]:
+            data.pop("branch")
+        resp = self.__request(
+            "POST",
+            f"/projects/{project_id}/branches",
+            headers={
+                "Accept": "application/json",
+                "Content-Type": "application/json",
+            },
+            json=data,
+        )
+        return cast("dict[str, Any]", resp.json())
+
+    def get_branch_details(self, project_id: str, branch_id: str) -> dict[str, Any]:
+        resp = self.__request(
+            "GET",
+            f"/projects/{project_id}/branches/{branch_id}",
+            headers={
+                "Accept": "application/json",
+            },
+        )
+        return cast("dict[str, Any]", resp.json())
+
+    def delete_branch(self, project_id: str, branch_id: str) -> dict[str, Any]:
+        resp = self.__request(
+            "DELETE",
+            f"/projects/{project_id}/branches/{branch_id}",
+            headers={
+                "Accept": "application/json",
+            },
+        )
+        return cast("dict[str, Any]", resp.json())
+
+    def restore_branch(
+        self,
+        project_id: str,
+        branch_id: str,
+        source_branch_id: str,
+        source_lsn: str | None,
+        source_timestamp: str | None,
+        preserve_under_name: str | None,
+    ):
+        data = {"source_branch_id": source_branch_id}
+        if source_lsn:
+            data["source_lsn"] = source_lsn
+        if source_timestamp:
+            data["source_timestamp"] = source_timestamp
+        if preserve_under_name:
+            data["preserve_under_name"] = preserve_under_name
+        log.info("Data: %s", data)
+        resp = self.__request(
+            "POST",
+            f"/projects/{project_id}/branches/{branch_id}/restore",
+            headers={
+                "Accept": "application/json",
+            },
+            json=data,
+        )
+        return cast("dict[str, Any]", resp.json())
+
     def start_endpoint(
         self,
         project_id: str,
@@ -176,6 +309,10 @@ class NeonAPI:
 
         return cast("dict[str, Any]", resp.json())
 
+    def delete_endpoint(self, project_id: str, endpoint_id: str) -> dict[str, Any]:
+        resp = self.__request("DELETE", f"/projects/{project_id}/endpoints/{endpoint_id}")
+        return cast("dict[str,Any]", resp.json())
+
     def get_connection_uri(
         self,
         project_id: str,

test_runner/fixtures/neon_fixtures.py

@@ -3185,6 +3185,7 @@ class PgBin:
         command: list[str],
         env: Env | None = None,
         cwd: str | Path | None = None,
+        stderr_pipe: Any | None = None,
     ) -> subprocess.Popen[Any]:
         """
         Run one of the postgres binaries, not waiting for it to finish
@@ -3202,7 +3203,9 @@ class PgBin:
         log.info(f"Running command '{' '.join(command)}'")
         env = self._build_env(env)
         self._log_env(env)
-        return subprocess.Popen(command, env=env, cwd=cwd, stdout=subprocess.PIPE, text=True)
+        return subprocess.Popen(
+            command, env=env, cwd=cwd, stdout=subprocess.PIPE, stderr=stderr_pipe, text=True
+        )
 
     def run(
         self,