From eeea38dab3e6e1b3f4a03f35997c5578cc3e77fa Mon Sep 17 00:00:00 2001
From: Nikolay Telepenin <ntelepenin@cloudlinux.com>
Date: Fri, 1 Sep 2023 12:24:20 +0100
Subject: [PATCH] Gerrit support

---
 pr_agent/git_providers/__init__.py        |   5 +-
 pr_agent/git_providers/gerrit_provider.py | 397 ++++++++++++++++++++++
 pr_agent/servers/gerrit_server.py         |  81 +++++
 pr_agent/settings/configuration.toml      |  14 +-
 4 files changed, 494 insertions(+), 3 deletions(-)
 create mode 100644 pr_agent/git_providers/gerrit_provider.py
 create mode 100644 pr_agent/servers/gerrit_server.py

diff --git a/pr_agent/git_providers/__init__.py b/pr_agent/git_providers/__init__.py
index 376d09f5..968f0dfc 100644
--- a/pr_agent/git_providers/__init__.py
+++ b/pr_agent/git_providers/__init__.py
@@ -5,6 +5,8 @@ from pr_agent.git_providers.github_provider import GithubProvider
 from pr_agent.git_providers.gitlab_provider import GitLabProvider
 from pr_agent.git_providers.local_git_provider import LocalGitProvider
 from pr_agent.git_providers.azuredevops_provider import AzureDevopsProvider
+from pr_agent.git_providers.gerrit_provider import GerritProvider
+
 
 _GIT_PROVIDERS = {
     'github': GithubProvider,
@@ -12,7 +14,8 @@ _GIT_PROVIDERS = {
     'bitbucket': BitbucketProvider,
     'azure': AzureDevopsProvider,
     'codecommit': CodeCommitProvider,
-    'local' : LocalGitProvider
+    'local' : LocalGitProvider,
+    'gerrit': GerritProvider,
 }
 
 def get_git_provider():
diff --git a/pr_agent/git_providers/gerrit_provider.py b/pr_agent/git_providers/gerrit_provider.py
new file mode 100644
index 00000000..d2a80a65
--- /dev/null
+++ b/pr_agent/git_providers/gerrit_provider.py
@@ -0,0 +1,397 @@
+import json
+import logging
+import os
+import pathlib
+import shutil
+import subprocess
+from collections import Counter, namedtuple
+from pathlib import Path
+from tempfile import mkdtemp, NamedTemporaryFile
+
+import requests
+import urllib3.util
+from git import Repo
+
+from pr_agent.config_loader import get_settings
+from pr_agent.git_providers.git_provider import GitProvider, FilePatchInfo, \
+    EDIT_TYPE
+from pr_agent.git_providers.local_git_provider import PullRequestMimic
+
+logger = logging.getLogger(__name__)
+
+
+def _call(*command, **kwargs) -> (int, str, str):
+    res = subprocess.run(
+        command,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
+        check=True,
+        **kwargs,
+    )
+    return res.stdout.decode()
+
+
+def clone(url, directory):
+    logger.info("Cloning %s to %s", url, directory)
+    stdout = _call('git', 'clone', "--depth", "1", url, directory)
+    logger.info(stdout)
+
+
+def fetch(url, refspec, cwd):
+    logger.info("Fetching %s %s", url, refspec)
+    stdout = _call(
+        'git', 'fetch', '--depth', '2', url, refspec,
+        cwd=cwd
+    )
+    logger.info(stdout)
+
+
+def checkout(cwd):
+    logger.info("Checking out")
+    stdout = _call('git', 'checkout', "FETCH_HEAD", cwd=cwd)
+    logger.info(stdout)
+
+
+def show(*args, cwd=None):
+    logger.info("Show")
+    return _call('git', 'show', *args, cwd=cwd)
+
+
+def diff(*args, cwd=None):
+    logger.info("Diff")
+    patch = _call('git', 'diff', *args, cwd=cwd)
+    if not patch:
+        logger.warning("No changes found")
+        return
+    return patch
+
+
+def reset_local_changes(cwd):
+    logger.info("Reset local changes")
+    _call('git', 'checkout', "--force", cwd=cwd)
+
+
+def add_comment(url: urllib3.util.Url, refspec, message):
+    *_, patchset, changenum = refspec.rsplit("/")
+    message = "'" + message.replace("'", "'\"'\"'") + "'"
+    return _call(
+        "ssh",
+        "-p", str(url.port),
+        f"{url.auth}@{url.host}",
+        "gerrit", "review",
+        "--message", message,
+        # "--code-review", score,
+        f"{patchset},{changenum}",
+    )
+
+
+def list_comments(url: urllib3.util.Url, refspec):
+    *_, patchset, _ = refspec.rsplit("/")
+    stdout = _call(
+        "ssh",
+        "-p", str(url.port),
+        f"{url.auth}@{url.host}",
+        "gerrit", "query",
+        "--comments",
+        "--current-patch-set", patchset,
+        "--format", "JSON",
+    )
+    change_set, *_ = stdout.splitlines()
+    return json.loads(change_set)["currentPatchSet"]["comments"]
+
+
+def prepare_repo(url: urllib3.util.Url, project, refspec):
+    repo_url = (f"{url.scheme}://{url.auth}@{url.host}:{url.port}/{project}")
+
+    directory = pathlib.Path(mkdtemp())
+    clone(repo_url, directory),
+    fetch(repo_url, refspec, cwd=directory)
+    checkout(cwd=directory)
+    return directory
+
+
+def adopt_to_gerrit_message(message):
+    lines = message.splitlines()
+    buf = []
+    for line in lines:
+        line = line.replace("*", "").replace("``", "`")
+        line = line.strip()
+        if line.startswith('#'):
+            buf.append("\n" +
+                       line.replace('#', '').removesuffix(":").strip() +
+                       ":")
+            continue
+        elif line.startswith('-'):
+            buf.append(line.removeprefix('-').strip())
+            continue
+        else:
+            buf.append(line)
+    return "\n".join(buf).strip()
+
+
+def add_suggestion(src_filename, context: str, start, end: int):
+    with (
+        NamedTemporaryFile("w", delete=False) as tmp,
+        open(src_filename, "r") as src
+    ):
+        lines = src.readlines()
+        tmp.writelines(lines[:start - 1])
+        if context:
+            tmp.write(context)
+        tmp.writelines(lines[end:])
+
+    shutil.copy(tmp.name, src_filename)
+    os.remove(tmp.name)
+
+
+def upload_patch(patch, path):
+    patch_server_endpoint = get_settings().get(
+        'gerrit.patch_server_endpoint')
+    patch_server_token = get_settings().get(
+        'gerrit.patch_server_token')
+
+    response = requests.post(
+        patch_server_endpoint,
+        json={
+            "content": patch,
+            "path": path,
+        },
+        headers={
+            "Content-Type": "application/json",
+            "Authorization": f"Bearer {patch_server_token}",
+        }
+    )
+    response.raise_for_status()
+    patch_server_endpoint = patch_server_endpoint.rstrip("/")
+    return patch_server_endpoint + "/" + path
+
+
+class GerritProvider(GitProvider):
+
+    def __init__(self, key: str, incremental=False):
+        self.project, self.refspec = key.split(':')
+        assert self.project, "Project name is required"
+        assert self.refspec, "Refspec is required"
+        base_url = get_settings().get('gerrit.url')
+        assert base_url, "Gerrit URL is required"
+        user = get_settings().get('gerrit.user')
+        assert user, "Gerrit user is required"
+
+        parsed = urllib3.util.parse_url(base_url)
+        self.parsed_url = urllib3.util.parse_url(
+            f"{parsed.scheme}://{user}@{parsed.host}:{parsed.port}"
+        )
+
+        self.repo_path = prepare_repo(
+            self.parsed_url, self.project, self.refspec
+        )
+        self.repo = Repo(self.repo_path)
+        assert self.repo
+
+        self.pr = PullRequestMimic(self.get_pr_title(), self.get_diff_files())
+
+    def get_pr_title(self):
+        """
+        Substitutes the branch-name as the PR-mimic title.
+        """
+        return self.repo.branches[0].name
+
+    def get_issue_comments(self):
+        # raise NotImplementedError(
+        #     'Getting comments is not implemented for the gerrit provider'
+        # )
+        # unclear how to get right comments from gerrit
+        # all user's comments like this "'Patch Set 1: (1 comment)'"
+        # i.e. it's not clear how to get the comment body
+
+        comments = list_comments(self.parsed_url, self.refspec)
+        Comments = namedtuple('Comments', ['reversed'])
+        Comment = namedtuple('Comment', ['body'])
+        return Comments([Comment(c['message']) for c in reversed(comments)])
+
+    def get_labels(self):
+        raise NotImplementedError(
+            'Getting labels is not implemented for the gerrit provider')
+
+    def add_eyes_reaction(self, issue_comment_id: int):
+        raise NotImplementedError(
+            'Adding reactions is not implemented for the gerrit provider')
+
+    def remove_reaction(self, issue_comment_id: int, reaction_id: int):
+        raise NotImplementedError(
+            'Removing reactions is not implemented for the gerrit provider')
+
+    def get_commit_messages(self):
+        return [self.repo.head.commit.message]
+
+    def get_repo_settings(self):
+        """
+        TODO: Implement support of .pr_agent.toml
+        """
+        return ""
+
+    def get_diff_files(self) -> list[FilePatchInfo]:
+        diffs = self.repo.head.commit.diff(
+            self.repo.head.commit.parents[0],  # previous commit
+            create_patch=True,
+            R=True
+        )
+
+        diff_files = []
+        for diff_item in diffs:
+            if diff_item.a_blob is not None:
+                original_file_content_str = (
+                    diff_item.a_blob.data_stream.read().decode('utf-8')
+                )
+            else:
+                original_file_content_str = ""  # empty file
+            if diff_item.b_blob is not None:
+                new_file_content_str = diff_item.b_blob.data_stream.read(). \
+                    decode('utf-8')
+            else:
+                new_file_content_str = ""  # empty file
+            edit_type = EDIT_TYPE.MODIFIED
+            if diff_item.new_file:
+                edit_type = EDIT_TYPE.ADDED
+            elif diff_item.deleted_file:
+                edit_type = EDIT_TYPE.DELETED
+            elif diff_item.renamed_file:
+                edit_type = EDIT_TYPE.RENAMED
+            diff_files.append(
+                FilePatchInfo(
+                    original_file_content_str,
+                    new_file_content_str,
+                    diff_item.diff.decode('utf-8'),
+                    diff_item.b_path,
+                    edit_type=edit_type,
+                    old_filename=None
+                    if diff_item.a_path == diff_item.b_path
+                    else diff_item.a_path
+                )
+            )
+        self.diff_files = diff_files
+        return diff_files
+
+    def get_files(self):
+        diff_index = self.repo.head.commit.diff(
+            self.repo.head.commit.parents[0],  # previous commit
+            R=True
+        )
+        # Get the list of changed files
+        diff_files = [item.a_path for item in diff_index]
+        return diff_files
+
+    def get_languages(self):
+        """
+        Calculate percentage of languages in repository. Used for hunk
+        prioritisation.
+        """
+        # Get all files in repository
+        filepaths = [Path(item.path) for item in
+                     self.repo.tree().traverse() if item.type == 'blob']
+        # Identify language by file extension and count
+        lang_count = Counter(
+            ext.lstrip('.') for filepath in filepaths for ext in
+            [filepath.suffix.lower()])
+        # Convert counts to percentages
+        total_files = len(filepaths)
+        lang_percentage = {lang: count / total_files * 100 for lang, count
+                           in lang_count.items()}
+        return lang_percentage
+
+    def get_pr_description(self):
+        return self.repo.head.commit.message
+
+    def get_user_id(self):
+        return self.repo.head.commit.author.email
+
+    def is_supported(self, capability: str) -> bool:
+        if capability in [
+            # 'get_issue_comments',
+            'create_inline_comment',
+            'publish_inline_comments',
+            'get_labels'
+        ]:
+            return False
+        return True
+
+    def split_suggestion(self, msg) -> tuple[str, str]:
+        is_code_context = False
+        description = []
+        context = []
+        for line in msg.splitlines():
+            if line.startswith('```suggestion'):
+                is_code_context = True
+                continue
+            if line.startswith('```'):
+                is_code_context = False
+                continue
+            if is_code_context:
+                context.append(line)
+            else:
+                description.append(
+                    line.replace('*', '')
+                )
+
+        return (
+            '\n'.join(description),
+            '\n'.join(context) + '\n' if context else ''
+        )
+
+    def publish_code_suggestions(self, code_suggestions: list):
+        msg = []
+        for i, suggestion in enumerate(code_suggestions):
+            description, code = self.split_suggestion(suggestion['body'])
+            add_suggestion(
+                pathlib.Path(self.repo_path) / suggestion["relevant_file"],
+                code,
+                suggestion["relevant_lines_start"],
+                suggestion["relevant_lines_end"],
+            )
+            patch = diff(cwd=self.repo_path)
+            path = "/".join(["codium-ai", self.refspec, str(i)])
+            full_path = upload_patch(patch, path)
+            reset_local_changes(self.repo_path)
+            msg.append(f'* {description}\n{full_path}')
+
+        if msg:
+            add_comment(self.parsed_url, self.refspec, "---\n".join(msg))
+
+    def publish_comment(self, pr_comment: str, is_temporary: bool = False):
+        if not is_temporary:
+            msg = adopt_to_gerrit_message(pr_comment)
+            add_comment(self.parsed_url, self.refspec, msg)
+
+    def publish_description(self, pr_title: str, pr_body: str):
+        msg = adopt_to_gerrit_message(pr_body)
+        add_comment(self.parsed_url, self.refspec, pr_title + '\n' + msg)
+
+    def publish_inline_comments(self, comments: list[dict]):
+        raise NotImplementedError(
+            'Publishing inline comments is not implemented for the gerrit '
+            'provider')
+
+    def publish_inline_comment(self, body: str, relevant_file: str,
+                               relevant_line_in_file: str):
+        raise NotImplementedError(
+            'Publishing inline comments is not implemented for the gerrit '
+            'provider')
+
+    def create_inline_comment(self, body: str, relevant_file: str,
+                              relevant_line_in_file: str):
+        raise NotImplementedError(
+            'Creating inline comments is not implemented for the gerrit '
+            'provider')
+
+    def publish_labels(self, labels):
+        # Not applicable to the local git provider,
+        # but required by the interface
+        pass
+
+    def remove_initial_comment(self):
+        # remove repo, cloned in previous steps
+        # shutil.rmtree(self.repo_path)
+        pass
+
+    def get_pr_branch(self):
+        return self.repo.head
diff --git a/pr_agent/servers/gerrit_server.py b/pr_agent/servers/gerrit_server.py
new file mode 100644
index 00000000..07ead55a
--- /dev/null
+++ b/pr_agent/servers/gerrit_server.py
@@ -0,0 +1,81 @@
+import copy
+import logging
+import sys
+from enum import Enum
+from json import JSONDecodeError
+
+import uvicorn
+from fastapi import APIRouter, FastAPI, HTTPException
+from pydantic import BaseModel
+from starlette.middleware import Middleware
+from starlette_context import context
+from starlette_context.middleware import RawContextMiddleware
+
+from pr_agent.agent.pr_agent import PRAgent
+from pr_agent.config_loader import global_settings, get_settings
+
+logging.basicConfig(stream=sys.stdout, level=logging.DEBUG)
+router = APIRouter()
+
+
+class Action(str, Enum):
+    review = "review"
+    describe = "describe"
+    ask = "ask"
+    improve = "improve"
+
+
+class Item(BaseModel):
+    refspec: str
+    project: str
+    msg: str = None
+
+
+@router.post("/api/v1/gerrit/{action}")
+async def handle_gerrit_request(action: Action, item: Item):
+    logging.debug("Received a Gerrit request")
+    context["settings"] = copy.deepcopy(global_settings)
+
+    agent = PRAgent()
+    pr_url = f"{item.project}:{item.refspec}"
+    if action == Action.review:
+        await agent.handle_request(pr_url, "/review")
+    elif action == Action.describe:
+        await agent.handle_request(pr_url, "/describe")
+    elif action == Action.improve:
+        await agent.handle_request(pr_url, "/improve")
+    elif action == Action.ask:
+        if not item.msg:
+            return HTTPException(
+                status_code=400,
+                detail="msg is required for ask command"
+            )
+        await agent.handle_request(pr_url, f"/ask {item.msg.strip()}")
+
+
+async def get_body(request):
+    try:
+        body = await request.json()
+    except JSONDecodeError as e:
+        logging.error("Error parsing request body", e)
+        return {}
+    return body
+
+
+@router.get("/")
+async def root():
+    return {"status": "ok"}
+
+
+def start():
+    # to prevent adding help messages with the output
+    get_settings().set("CONFIG.CLI_MODE", True)
+    middleware = [Middleware(RawContextMiddleware)]
+    app = FastAPI(middleware=middleware)
+    app.include_router(router)
+
+    uvicorn.run(app, host="0.0.0.0", port=3000)
+
+
+if __name__ == '__main__':
+    start()
diff --git a/pr_agent/settings/configuration.toml b/pr_agent/settings/configuration.toml
index f8abd555..4dfc80c8 100644
--- a/pr_agent/settings/configuration.toml
+++ b/pr_agent/settings/configuration.toml
@@ -1,7 +1,7 @@
 [config]
 model="gpt-4"
 fallback_models=["gpt-3.5-turbo-16k"]
-git_provider="github"
+git_provider="gerrit"
 publish_output=true
 publish_output_progress=true
 verbosity_level=0 # 0,1,2
@@ -84,4 +84,14 @@ polling_interval_seconds = 30
 [local]
 # LocalGitProvider settings - uncomment to use paths other than default
 # description_path= "path/to/description.md"
-# review_path= "path/to/review.md"
\ No newline at end of file
+# review_path= "path/to/review.md"
+
+[gerrit]
+# endpoint to the gerrit service
+# url = "ssh://gerrit.example.com:29418"
+# user for gerrit authentication
+# user = "ai-reviewer"
+# patch server where patches will be saved
+# patch_server_endpoint = "http://127.0.0.1:5000/patch"
+# token to authenticate in the patch server
+# patch_server_token = ""