feat(code): unified PR creation workflow

Author: adboio

apps/code/src/main/services/git/create-pr-flow-saga.ts

@@ -0,0 +1,212 @@
+import { getGitOperationManager } from "@posthog/git/operation-manager";
+import { getHeadSha } from "@posthog/git/queries";
+import { Saga, type SagaLogger } from "@posthog/shared";
+import type { LlmCredentials } from "../llm-gateway/schemas";
+import type {
+  ChangedFile,
+  CommitOutput,
+  CreatePrFlowProgressPayload,
+  CreatePrOutput,
+  GitSyncStatus,
+  PublishOutput,
+  PushOutput,
+} from "./schemas";
+
+export interface CreatePrFlowSagaInput {
+  directoryPath: string;
+  branchName?: string;
+  commitMessage?: string;
+  prTitle?: string;
+  prBody?: string;
+  draft?: boolean;
+  credentials?: LlmCredentials;
+}
+
+export interface CreatePrFlowSagaOutput {
+  prUrl: string | null;
+}
+
+export interface CreatePrFlowDeps {
+  getCurrentBranch(dir: string): Promise<string | null>;
+  createBranch(dir: string, name: string): Promise<void>;
+  checkoutBranch(
+    dir: string,
+    name: string,
+  ): Promise<{ previousBranch: string; currentBranch: string }>;
+  getChangedFilesHead(dir: string): Promise<ChangedFile[]>;
+  generateCommitMessage(
+    dir: string,
+    credentials: LlmCredentials,
+  ): Promise<{ message: string }>;
+  commit(dir: string, message: string): Promise<CommitOutput>;
+  getSyncStatus(dir: string): Promise<GitSyncStatus>;
+  push(dir: string): Promise<PushOutput>;
+  publish(dir: string): Promise<PublishOutput>;
+  generatePrTitleAndBody(
+    dir: string,
+    credentials: LlmCredentials,
+  ): Promise<{ title: string; body: string }>;
+  createPr(
+    dir: string,
+    title?: string,
+    body?: string,
+    draft?: boolean,
+  ): Promise<CreatePrOutput>;
+  onProgress(
+    step: CreatePrFlowProgressPayload["step"],
+    message: string,
+    prUrl?: string,
+  ): void;
+}
+
+export class CreatePrFlowSaga extends Saga<
+  CreatePrFlowSagaInput,
+  CreatePrFlowSagaOutput
+> {
+  readonly sagaName = "CreatePrFlowSaga";
+  private deps: CreatePrFlowDeps;
+
+  constructor(deps: CreatePrFlowDeps, logger?: SagaLogger) {
+    super(logger);
+    this.deps = deps;
+  }
+
+  protected async execute(
+    input: CreatePrFlowSagaInput,
+  ): Promise<CreatePrFlowSagaOutput> {
+    const { directoryPath, draft, credentials } = input;
+    let { commitMessage, prTitle, prBody } = input;
+
+    if (input.branchName) {
+      this.deps.onProgress(
+        "creating-branch",
+        `Creating branch ${input.branchName}...`,
+      );
+
+      const originalBranch = await this.readOnlyStep(
+        "get-original-branch",
+        () => this.deps.getCurrentBranch(directoryPath),
+      );
+
+      await this.step({
+        name: "creating-branch",
+        execute: () => this.deps.createBranch(directoryPath, input.branchName!),
+        rollback: async () => {
+          if (originalBranch) {
+            await this.deps.checkoutBranch(directoryPath, originalBranch);
+          }
+        },
+      });
+    }
+
+    const changedFiles = await this.readOnlyStep("check-changes", () =>
+      this.deps.getChangedFilesHead(directoryPath),
+    );
+
+    if (changedFiles.length > 0) {
+      // Generate commit message if not provided
+      if (!commitMessage && credentials) {
+        this.deps.onProgress("committing", "Generating commit message...");
+        const generated = await this.readOnlyStep(
+          "generate-commit-message",
+          async () => {
+            try {
+              return await this.deps.generateCommitMessage(
+                directoryPath,
+                credentials,
+              );
+            } catch {
+              return null;
+            }
+          },
+        );
+        if (generated) commitMessage = generated.message;
+      }
+
+      if (!commitMessage) {
+        throw new Error("Commit message is required.");
+      }
+
+      this.deps.onProgress("committing", "Committing changes...");
+
+      const preCommitSha = await this.readOnlyStep("get-pre-commit-sha", () =>
+        getHeadSha(directoryPath),
+      );
+
+      await this.step({
+        name: "committing",
+        execute: async () => {
+          const result = await this.deps.commit(directoryPath, commitMessage!);
+          if (!result.success) throw new Error(result.message);
+          return result;
+        },
+        rollback: async () => {
+          const manager = getGitOperationManager();
+          await manager.executeWrite(directoryPath, (git) =>
+            git.reset(["--soft", preCommitSha]),
+          );
+        },
+      });
+    }
+
+    this.deps.onProgress("pushing", "Pushing to remote...");
+
+    const syncStatus = await this.readOnlyStep("check-sync-status", () =>
+      this.deps.getSyncStatus(directoryPath),
+    );
+
+    await this.step({
+      name: "pushing",
+      execute: async () => {
+        const result = syncStatus.hasRemote
+          ? await this.deps.push(directoryPath)
+          : await this.deps.publish(directoryPath);
+        if (!result.success) throw new Error(result.message);
+        return result;
+      },
+      // Push can't be meaningfully rolled back without force-push
+      rollback: async () => {},
+    });
+
+    if ((!prTitle || !prBody) && credentials) {
+      this.deps.onProgress("creating-pr", "Generating PR description...");
+      const generated = await this.readOnlyStep(
+        "generate-pr-description",
+        async () => {
+          try {
+            return await this.deps.generatePrTitleAndBody(
+              directoryPath,
+              credentials,
+            );
+          } catch {
+            return null;
+          }
+        },
+      );
+      if (generated) {
+        if (!prTitle) prTitle = generated.title;
+        if (!prBody) prBody = generated.body;
+      }
+    }
+
+    this.deps.onProgress("creating-pr", "Creating pull request...");
+
+    const prResult = await this.step({
+      name: "creating-pr",
+      execute: async () => {
+        const result = await this.deps.createPr(
+          directoryPath,
+          prTitle || undefined,
+          prBody || undefined,
+          draft,
+        );
+        if (!result.success) throw new Error(result.message);
+        return result;
+      },
+      // PR creation doesn't need rollback — the branch/commit are already pushed
+      rollback: async () => {},
+    });
+
+    return { prUrl: prResult.prUrl };
+  }
+}

apps/code/src/main/services/git/schemas.ts

@@ -414,3 +414,54 @@ export const searchGithubIssuesInput = z.object({
 });
 
 export const searchGithubIssuesOutput = z.array(githubIssueSchema);
+
+// Create PR flow (composite operation)
+export const createPrFlowStep = z.enum([
+  "creating-branch",
+  "committing",
+  "pushing",
+  "creating-pr",
+  "complete",
+  "error",
+]);
+
+export type CreatePrFlowStep = z.infer<typeof createPrFlowStep>;
+
+export const createPrFlowInput = z.object({
+  directoryPath: z.string(),
+  flowId: z.string(),
+  branchName: z.string().optional(),
+  commitMessage: z.string().optional(),
+  prTitle: z.string().optional(),
+  prBody: z.string().optional(),
+  draft: z.boolean().optional(),
+  credentials: z
+    .object({
+      apiKey: z.string(),
+      apiHost: z.string(),
+    })
+    .optional(),
+});
+
+export type CreatePrFlowInput = z.infer<typeof createPrFlowInput>;
+
+export const createPrFlowProgressPayload = z.object({
+  flowId: z.string(),
+  step: createPrFlowStep,
+  message: z.string(),
+  prUrl: z.string().optional(),
+});
+
+export type CreatePrFlowProgressPayload = z.infer<
+  typeof createPrFlowProgressPayload
+>;
+
+export const createPrFlowOutput = z.object({
+  success: z.boolean(),
+  message: z.string(),
+  prUrl: z.string().nullable(),
+  failedStep: createPrFlowStep.nullable(),
+  state: gitStateSnapshotSchema.optional(),
+});
+
+export type CreatePrFlowOutput = z.infer<typeof createPrFlowOutput>;