Prometheus exporter for github repo stats (#38607)

* Prometheus exporter for github repo stats

I want more grafana charts

Already deployed on moon, this is just so other codebases can use it if they want.

* Add docs and issue/PR priorities

* Sure add merge conflicts too

Tools/github_repo_stats.py

@@ -0,0 +1,241 @@
+#!/usr/bin/env python3
+
+import argparse
+import requests
+import itertools
+import signal
+import sdnotify
+import os
+from io import StringIO
+from abc import ABC, abstractmethod
+from enum import Enum
+from dataclasses import dataclass
+from typing import Iterable, TypeVar, Callable, Any, Optional
+from prometheus_client import start_http_server, CollectorRegistry
+from prometheus_client.core import Metric, GaugeMetricFamily
+import time
+# from prometheus_client.registry import Collector
+
+GITHUB_API_URL = "https://api.github.com/graphql"
+GITHUB_TOKEN = os.environ["SS14_REPO_STATS_GITHUB_TOKEN"]
+USER_AGENT = "github_repo_stats.py/1.0.0"
+
+# We have a GraphQL client at home
+
+class AbstractQuery(ABC):
+    @abstractmethod
+    def get_selector(self, alias: str):
+        pass
+
+class IssueState(Enum):
+    CLOSED = 1,
+    OPEN = 2,
+
+class IssueQuery(AbstractQuery):
+    def __init__(self, states: Optional[list[IssueState]] = None, labels: Optional[list[str]] = None) -> None:
+        super().__init__()
+
+        self.states = states
+        self.labels = labels
+
+    def get_selector(self, alias: str):
+        query_args = []
+        if self.states and len(self.states):
+            query_args.append(f"states:{enum_join(self.states)}")
+        if self.labels and len(self.labels):
+            query_args.append(f"labels:{labels_join(self.labels)}")
+
+        args = f"({','.join(query_args)})" if len(query_args) else ""
+
+        return f"{alias}: issues{args}"
+
+class PullRequestState(Enum):
+    CLOSED = 1,
+    MERGED = 2
+    OPEN = 3,
+
+class PullRequestQuery(AbstractQuery):
+    def __init__(self, states: Optional[list[PullRequestState]] = None, labels: Optional[list[str]] = None) -> None:
+        super().__init__()
+
+        self.states = states
+        self.labels = labels
+
+    def get_selector(self, alias: str):
+        query_args = []
+        if self.states and len(self.states):
+            query_args.append(f"states:{enum_join(self.states)}")
+
+        if self.labels and len(self.labels):
+            query_args.append(f"labels:{labels_join(self.labels)}")
+
+        args = f"({','.join(query_args)})" if len(query_args) else ""
+
+        return f"{alias}: pullRequests{args}"
+
+@dataclass
+class Repo:
+    owner: str
+    name: str
+
+    queries: dict[str, AbstractQuery]
+
+LABEL_UNTRIAGED = "S: Untriaged"
+LABEL_NEEDS_REVIEW = "S: Needs Review"
+LABEL_AWAITING_CHANGES = "S: Awaiting Changes"
+LABEL_APPROVED = "S: Approved"
+LABEL_P0 = "P0: Critical"
+LABEL_P1 = "P1: High"
+LABEL_CONFLICT = "S: Merge Conflict"
+
+REPO_CONFIG = [
+    Repo("space-wizards", "space-station-14", queries={
+        # Issue queries
+        "issue_total_count": IssueQuery(),
+        "issue_open_count": IssueQuery(states=[IssueState.OPEN]),
+        "issue_closed_count": IssueQuery(states=[IssueState.CLOSED]),
+        "issue_untriaged_count": IssueQuery(states=[IssueState.OPEN], labels=[LABEL_UNTRIAGED]),
+
+        # PR queries
+        "pr_total_count": PullRequestQuery(),
+        "pr_open_count": PullRequestQuery(states=[PullRequestState.OPEN]),
+        "pr_closed_count": PullRequestQuery(states=[PullRequestState.CLOSED]),
+        "pr_merged_count": PullRequestQuery(states=[PullRequestState.MERGED]),
+        "pr_untriaged_count": PullRequestQuery(states=[PullRequestState.OPEN], labels=[LABEL_UNTRIAGED]),
+        "pr_needs_review_count": PullRequestQuery(states=[PullRequestState.OPEN], labels=[LABEL_NEEDS_REVIEW]),
+        "pr_awaiting_changes_count": PullRequestQuery(states=[PullRequestState.OPEN], labels=[LABEL_AWAITING_CHANGES]),
+        "pr_approved_count": PullRequestQuery(states=[PullRequestState.OPEN], labels=[LABEL_APPROVED]),
+        "pr_p0_count": PullRequestQuery(states=[PullRequestState.OPEN], labels=[LABEL_P0]),
+        "pr_p1_count": PullRequestQuery(states=[PullRequestState.OPEN], labels=[LABEL_P1]),
+        "pr_conflict_count": PullRequestQuery(states=[PullRequestState.OPEN], labels=[LABEL_CONFLICT]),
+    }),
+    Repo("space-wizards", "RobustToolbox", queries={
+        # Issue queries
+        "issue_total_count": IssueQuery(),
+        "issue_open_count": IssueQuery(states=[IssueState.OPEN]),
+        "issue_closed_count": IssueQuery(states=[IssueState.CLOSED]),
+        "issue_untriaged_count": IssueQuery(states=[IssueState.OPEN], labels=[LABEL_UNTRIAGED]),
+
+        # PR queries
+        "pr_total_count": PullRequestQuery(),
+        "pr_open_count": PullRequestQuery(states=[PullRequestState.OPEN]),
+        "pr_closed_count": PullRequestQuery(states=[PullRequestState.CLOSED]),
+        "pr_merged_count": PullRequestQuery(states=[PullRequestState.MERGED]),
+        "pr_untriaged_count": PullRequestQuery(states=[PullRequestState.OPEN], labels=[LABEL_UNTRIAGED]),
+        "pr_needs_review_count": PullRequestQuery(states=[PullRequestState.OPEN], labels=[LABEL_NEEDS_REVIEW]),
+        "pr_awaiting_changes_count": PullRequestQuery(states=[PullRequestState.OPEN], labels=[LABEL_AWAITING_CHANGES]),
+    }),
+    Repo("space-wizards", "docs", queries={
+        # Issue queries
+        "issue_total_count": IssueQuery(),
+        "issue_open_count": IssueQuery(states=[IssueState.OPEN]),
+        "issue_closed_count": IssueQuery(states=[IssueState.CLOSED]),
+
+        # PR queries
+        "pr_total_count": PullRequestQuery(),
+        "pr_open_count": PullRequestQuery(states=[PullRequestState.OPEN]),
+        "pr_closed_count": PullRequestQuery(states=[PullRequestState.CLOSED]),
+        "pr_merged_count": PullRequestQuery(states=[PullRequestState.MERGED]),
+    }),
+]
+
+E = TypeVar("E", bound=Enum)
+def enum_join(iterable: Iterable[E]) -> str:
+    return f"[{','.join((e.name for e in iterable))}]"
+
+def labels_join(iterable: Iterable[str]) -> str:
+    contents = ','.join(map(graphql_string, iterable))
+    return f"[{contents}]"
+
+T = TypeVar("T")
+def first_or_default(iterable: Iterable[T], func: Callable[[T], bool]) -> Optional[T]:
+    for val in iterable:
+        if func(val):
+            return val
+
+    return None
+
+REQUESTS_SESSION = requests.Session()
+REQUESTS_SESSION.headers["User-Agent"] = USER_AGENT
+
+def graphql_string(val: str) -> str:
+    # This is probably good enough.
+    # Note that this script doesn't accept (potentially malicious) user input.
+    # If it did, I wouldn't be doing it like this.
+    val_replaced = val.replace('"', '\\"')
+    return f"\"{val_replaced}\""
+
+def generate_graphql_query_for_repo(repo: Repo) -> str:
+    strio = StringIO()
+
+    strio.write("query {\n")
+    strio.write(f"\trepository(owner: {graphql_string(repo.owner)}, name: {graphql_string(repo.name)})" + " {\n")
+
+    for key, query in repo.queries.items():
+        strio.write(f"\t\t{query.get_selector(key)}" + " {\n")
+        strio.write("\t\t\ttotalCount\n")
+        strio.write("\t\t}\n")
+
+    strio.write("\t}\n")
+    strio.write("}\n")
+
+    return strio.getvalue()
+
+def repo_key(repo: Repo) -> str:
+    return f"{repo.owner}/{repo.name}"
+
+def do_graphql_query(query: str) -> Any:
+    with REQUESTS_SESSION.post(GITHUB_API_URL, headers={"Authorization": f"Bearer {GITHUB_TOKEN}"}, json={"query": query}) as resp:
+        resp.raise_for_status()
+        return resp.json()
+
+CACHED_QUERIES = {repo_key(repo): generate_graphql_query_for_repo(repo) for repo in REPO_CONFIG}
+
+# RHEL 9 ships with an old version of prometheus_client that doesn't have the "Collector" type...
+class StatsCollector: #(Collector):
+    def collect(self) -> Iterable[Metric]:
+        query_time_metric = GaugeMetricFamily("repo_stats_query_time", "Time the GitHub query API call took", labels=["repo"])
+        metrics: dict[str, GaugeMetricFamily] = {}
+        # Make all the metric families.
+        for repo in REPO_CONFIG:
+            r_key = repo_key(repo)
+            for key in repo.queries.keys():
+                if key not in metrics:
+                    metrics[key] = GaugeMetricFamily(f"repo_stats_{key}", key, labels=["repo"])
+
+            # Do the requests and fill out the stats.
+            query = CACHED_QUERIES[r_key]
+            start_time = time.monotonic_ns()
+            query_data = do_graphql_query(query)
+            end_time = time.monotonic_ns()
+            repo_data = query_data["data"]["repository"]
+
+            for key in repo.queries.keys():
+                value = repo_data[key]["totalCount"]
+                metrics[key].add_metric([r_key], float(value))
+
+            query_time_metric.add_metric([r_key], (end_time - start_time) / 1_000_000_000)
+
+        yield from metrics.values()
+        yield query_time_metric
+
+def main() -> None:
+    parser = argparse.ArgumentParser()
+    parser.add_argument("port", type=int)
+    parser.add_argument("--host", default="0.0.0.0")
+
+    args = parser.parse_args()
+
+    port = args.port
+    host = args.host
+
+    registry = CollectorRegistry(auto_describe=True)
+    registry.register(StatsCollector())
+
+    start_http_server(port, host, registry)
+
+    sdnotify.SystemdNotifier().notify("READY=1")
+
+    signal.pause()
+
+main()