feat: add GET /api/commit endpoint and improve git API response formats

CHANGELOG.md

@@ -7,8 +7,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+- Added `GET /api/commit` endpoint for retrieving details about a single commit, including parent commit SHAs [#1077](https://github.com/sourcebot-dev/sourcebot/pull/1077)
+
 ### Changed
 - Replaced placeholder avatars with deterministic minidenticon-based avatars generated from email addresses [#1072](https://github.com/sourcebot-dev/sourcebot/pull/1072)
+- Changed `author_name` and `author_email` fields to `authorName` and `authorEmail` in `GET /api/commits` response [#1077](https://github.com/sourcebot-dev/sourcebot/pull/1077)
+- Changed `oldPath` and `newPath` in `GET /api/diff` response from `"/dev/null"` to `null` for added/deleted files [#1077](https://github.com/sourcebot-dev/sourcebot/pull/1077)
 
 ## [4.16.4] - 2026-04-01
 

docs/api-reference/sourcebot-public.openapi.json

@@ -619,11 +619,13 @@
               "properties": {
                 "oldPath": {
                   "type": "string",
-                  "description": "The file path before the change. `/dev/null` for added files."
+                  "nullable": true,
+                  "description": "The file path before the change. `null` for added files."
                 },
                 "newPath": {
                   "type": "string",
-                  "description": "The file path after the change. `/dev/null` for deleted files."
+                  "nullable": true,
+                  "description": "The file path after the change. `null` for deleted files."
                 },
                 "hunks": {
                   "type": "array",
@@ -892,10 +894,10 @@
             "type": "string",
             "description": "The commit body (everything after the subject line)."
           },
-          "author_name": {
+          "authorName": {
             "type": "string"
           },
-          "author_email": {
+          "authorEmail": {
             "type": "string"
           }
         },
@@ -905,8 +907,8 @@
           "message",
           "refs",
           "body",
-          "author_name",
-          "author_email"
+          "authorName",
+          "authorEmail"
         ]
       },
       "PublicListCommitsResponse": {
@@ -915,6 +917,54 @@
           "$ref": "#/components/schemas/PublicCommit"
         }
       },
+      "PublicCommitDetail": {
+        "type": "object",
+        "properties": {
+          "hash": {
+            "type": "string",
+            "description": "The full commit SHA."
+          },
+          "date": {
+            "type": "string",
+            "description": "The commit date in ISO 8601 format."
+          },
+          "message": {
+            "type": "string",
+            "description": "The commit subject line."
+          },
+          "refs": {
+            "type": "string",
+            "description": "Refs pointing to this commit (e.g. branch or tag names)."
+          },
+          "body": {
+            "type": "string",
+            "description": "The commit body (everything after the subject line)."
+          },
+          "authorName": {
+            "type": "string"
+          },
+          "authorEmail": {
+            "type": "string"
+          },
+          "parents": {
+            "type": "array",
+            "items": {
+              "type": "string"
+            },
+            "description": "The parent commit SHAs."
+          }
+        },
+        "required": [
+          "hash",
+          "date",
+          "message",
+          "refs",
+          "body",
+          "authorName",
+          "authorEmail",
+          "parents"
+        ]
+      },
       "PublicEeUser": {
         "type": "object",
         "properties": {
@@ -1820,6 +1870,80 @@
         }
       }
     },
+    "/api/commit": {
+      "get": {
+        "operationId": "getCommit",
+        "tags": [
+          "Git"
+        ],
+        "summary": "Get commit details",
+        "description": "Returns details for a single commit, including parent commit SHAs.",
+        "parameters": [
+          {
+            "schema": {
+              "type": "string",
+              "description": "The fully-qualified repository name."
+            },
+            "required": true,
+            "description": "The fully-qualified repository name.",
+            "name": "repo",
+            "in": "query"
+          },
+          {
+            "schema": {
+              "type": "string",
+              "description": "The git ref (commit SHA, branch, or tag)."
+            },
+            "required": true,
+            "description": "The git ref (commit SHA, branch, or tag).",
+            "name": "ref",
+            "in": "query"
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Commit details.",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/PublicCommitDetail"
+                }
+              }
+            }
+          },
+          "400": {
+            "description": "Invalid query parameters or git ref.",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/PublicApiServiceError"
+                }
+              }
+            }
+          },
+          "404": {
+            "description": "Repository or revision not found.",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/PublicApiServiceError"
+                }
+              }
+            }
+          },
+          "500": {
+            "description": "Unexpected failure.",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/PublicApiServiceError"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
     "/api/ee/user": {
       "get": {
         "operationId": "getUser",

docs/docs.json

@@ -172,6 +172,7 @@
                         "group": "Git",
                         "icon": "code-branch",
                         "pages": [
+                            "GET /api/commit",
                             "GET /api/diff",
                             "GET /api/commits",
                             "GET /api/source",

packages/mcp/src/schemas.ts

@@ -360,8 +360,8 @@ export const listCommitsResponseSchema = z.array(z.object({
     message: z.string(),
     refs: z.string(),
     body: z.string(),
-    author_name: z.string(),
-    author_email: z.string(),
+    authorName: z.string(),
+    authorEmail: z.string(),
 }));
 
 export const languageModelInfoSchema = z.object({

packages/web/src/app/api/(server)/commit/route.ts

@@ -0,0 +1,30 @@
+import { getCommit } from "@/features/git";
+import { getCommitQueryParamsSchema } from "@/features/git/schemas";
+import { apiHandler } from "@/lib/apiHandler";
+import { queryParamsSchemaValidationError, serviceErrorResponse } from "@/lib/serviceError";
+import { isServiceError } from "@/lib/utils";
+import { NextRequest } from "next/server";
+
+export const GET = apiHandler(async (request: NextRequest): Promise<Response> => {
+    const rawParams = Object.fromEntries(
+        Object.keys(getCommitQueryParamsSchema.shape).map(key => [
+            key,
+            request.nextUrl.searchParams.get(key) ?? undefined
+        ])
+    );
+    const parsed = getCommitQueryParamsSchema.safeParse(rawParams);
+
+    if (!parsed.success) {
+        return serviceErrorResponse(
+            queryParamsSchemaValidationError(parsed.error)
+        );
+    }
+
+    const result = await getCommit(parsed.data);
+
+    if (isServiceError(result)) {
+        return serviceErrorResponse(result);
+    }
+
+    return Response.json(result);
+});

packages/web/src/features/git/getCommitApi.ts

@@ -0,0 +1,103 @@
+import { sew } from "@/middleware/sew";
+import { invalidGitRef, notFound, ServiceError, unexpectedError } from '@/lib/serviceError';
+import { withOptionalAuth } from '@/middleware/withAuth';
+import { getRepoPath } from '@sourcebot/shared';
+import { z } from 'zod';
+import { simpleGit } from 'simple-git';
+import { commitDetailSchema } from './schemas';
+import { isGitRefValid } from './utils';
+
+export type CommitDetail = z.infer<typeof commitDetailSchema>;
+
+type GetCommitRequest = {
+    repo: string;
+    ref: string;
+}
+
+// Field separator that won't appear in commit data
+const FIELD_SEP = '\x1f';
+const FORMAT = [
+    '%H',   // hash
+    '%aI',  // author date ISO 8601
+    '%s',   // subject
+    '%D',   // refs
+    '%b',   // body
+    '%aN',  // author name
+    '%aE',  // author email
+    '%P',   // parent hashes (space-separated)
+].join(FIELD_SEP);
+
+export const getCommit = async ({
+    repo: repoName,
+    ref,
+}: GetCommitRequest): Promise<CommitDetail | ServiceError> => sew(() =>
+    withOptionalAuth(async ({ org, prisma }) => {
+        const repo = await prisma.repo.findFirst({
+            where: {
+                name: repoName,
+                orgId: org.id,
+            },
+        });
+
+        if (!repo) {
+            return notFound(`Repository "${repoName}" not found.`);
+        }
+
+        if (!isGitRefValid(ref)) {
+            return invalidGitRef(ref);
+        }
+
+        const { path: repoPath } = getRepoPath(repo);
+        const git = simpleGit().cwd(repoPath);
+
+        try {
+            const output = (await git.raw([
+                'log',
+                '-1',
+                `--format=${FORMAT}`,
+                ref,
+            ])).trim();
+
+            const fields = output.split(FIELD_SEP);
+            if (fields.length < 8) {
+                return unexpectedError(`Failed to parse commit data for revision "${ref}".`);
+            }
+
+            const [hash, date, message, refs, body, authorName, authorEmail, parentStr] = fields;
+            const parents = parentStr.trim() === '' ? [] : parentStr.trim().split(' ');
+
+            return {
+                hash,
+                date,
+                message,
+                refs,
+                body,
+                authorName,
+                authorEmail,
+                parents,
+            };
+        } catch (error: unknown) {
+            const errorMessage = error instanceof Error ? error.message : String(error);
+
+            if (errorMessage.includes('not a git repository')) {
+                return unexpectedError(
+                    `Invalid git repository at ${repoPath}. ` +
+                    `The directory exists but is not a valid git repository.`
+                );
+            }
+
+            if (errorMessage.includes('unknown revision') || errorMessage.includes('bad object')) {
+                return notFound(`Revision "${ref}" not found in repository "${repoName}".`);
+            }
+
+            if (error instanceof Error) {
+                throw new Error(
+                    `Failed to get commit in repository ${repoName}: ${error.message}`
+                );
+            } else {
+                throw new Error(
+                    `Failed to get commit in repository ${repoName}: ${errorMessage}`
+                );
+            }
+        }
+    }));

packages/web/src/features/git/getDiffApi.ts

@@ -19,8 +19,8 @@ export interface DiffHunk {
 }
 
 export interface FileDiff {
-    oldPath: string;
-    newPath: string;
+    oldPath: string | null;
+    newPath: string | null;
     hunks: DiffHunk[];
 }
 
@@ -67,8 +67,8 @@ export const getDiff = async ({
             const files = parseDiff(rawDiff);
 
             const nodes: FileDiff[] = files.map((file) => ({
-                oldPath: file.from ?? '/dev/null',
-                newPath: file.to ?? '/dev/null',
+                oldPath: file.from && file.from !== '/dev/null' ? file.from : null,
+                newPath: file.to && file.to !== '/dev/null' ? file.to : null,
                 hunks: file.chunks.map((chunk) => {
                     // chunk.content is the full @@ header line, e.g.:
                     // "@@ -7,6 +7,8 @@ some heading text"

packages/web/src/features/git/index.ts

@@ -1,3 +1,4 @@
+export * from './getCommitApi';
 export * from './getDiffApi';
 export * from './getFilesApi';
 export * from './getFolderContentsApi';