A local ABAP application server inside VS Code. No SAP or ADT connection needed.

SAP kernel rejections now appear as red squiggles while typing, with a Problems link to the support section. osg.kernelStrict defaults to error and allows runs; choose warning, off, or refuse (also stops object runs and tests). Desktop VSIX installs include the scanner and its dependencies.

open-steamgate

Start a bundled ABAP runtime, explore its OData services, run ABAP Unit, and open local Fiori apps. The extension carries its own system seed and builds it on first start.

Quick start

1. Install open-steamgate from the VS Code Marketplace, or install the downloaded .vsix with Extensions: Install from VSIX....
2. Open the OSD Activity Bar view and select Start. The first start builds the bundled system; later starts reuse its cache.
3. Run OSD: Open sample from the command palette or the system status bar. Choose a bundled notebook and run a cell; the command offers to start OSD if needed. In an osg-demo workspace, it also offers ZOSD_DEMO_HELLO (press F9 to run).

The status bar shows OSD running/stopped, the serving OSD generation, and OSD jobs (when enabled for a file SQLite database). Click the system item for start actions or System overview, and the jobs item to open OSD Jobs.

VS Code 1.101 or newer is required. The system runs locally on desktop or in a Remote-WSL or Remote-SSH workspace. It does not need a SAP or ADT connection.

The editor’s ▷ button runs classrun (F9) when the class implements IF_OO_ADT_CLASSRUN. The beaker runs ABAP Unit and appears for classes with test methods; it runs exactly the same command as Ctrl+Shift+F10 (testing.runCurrentFile). Tests also run through the Test Explorer. F8 / ▷ / F9 never run ABAP Unit. F8 runs classrun for a class implementing IF_OO_ADT_CLASSRUN, even when it has tests; reports run in a terminal, and tables/CDS views open Data Preview. Other supported run actions keep their object dispatch. A class with nothing to run shows “Nothing to run for . Tests: Ctrl+Shift+F10.” Each button’s tooltip names its action and key.

What works

• Start and stop the local server; inspect its services and generation in the OSD tree.
• Run ABAP Unit in Test Explorer; check, activate, and run ABAP files with familiar keys.
• Open local OData and Fiori apps, inspect short dumps, use SQL notebooks, and debug ABAP through VS Code's Node debugger.
• Add an abapGit-style workspace layer over the bundled source.

What connects to what

The osd system is a local ABAP server. Start builds and launches it on its allocated HTTP port (shown in OSD running and System overview). osd.url points extension requests to that listener; independently started systems default to port 3030.

The ABAP-FS mount OSD (local) (osd-local) exposes source from that same server over ADT. It is a filesystem connection, independent of debugging.

The osd debugger attaches VS Code’s Node debugger on demand when you set an ABAP breakpoint while the system runs, or press F9 / ▷ with a breakpoint already set. Start system never starts a debug session, even with saved breakpoints. No launch configuration is needed. The SAP ADT and ABAP-FS debuggers are unrelated to osd: Attach to server, ABAP on server, and ABAP Replay Debugger target SAP systems.

Each Output channel starts with a line explaining its contents:

• OSD: extension diagnostics and command/debugger activity.
• OSD: Console: classrun/F9 output and Check/Activate feedback.
• OSD: System log: server build/runtime logs and debugger attachment diagnostics.
• OSD: Jobs: job summaries, or worker JSON events and diagnostics after the explicit Show raw job log action. Show jobs restores summaries.

ABAP values in the debugger

When stopped on an ABAP line, Variables, Watch and hover show ABAP values: 'ABC' (c20), 12.50 (p8,2), 42 (i), 9223372036854775807 (int8), 2026-10-03 (d), 12:34:56 (t), and ABCDEF (xstring). Character values omit trailing padding; strings preserve it. Float values use scientific notation with a locale-independent decimal point, and fixed hex includes its byte length (ABCD0000 (x4)).

Expand {…} (structure) to see its declared lowercase components. Tables show [3 rows] (standard table) (or sorted) and expand to rows 1, 2, 3. Field symbols and data references show -> followed by the target value and expand through a -> child. Unassigned/initial references say so. Objects show their class name and expand to ABAP attributes, including private attributes exposed by the transpiler.

The view shows the first 100 standard/sorted table rows, with a …more count for the rest; that node does not load more rows. Hashed tables show a summary without enumerating rows: the installed runtime has no bounded iterator or maintained count. Text and hex previews stop after 256 storage characters. CHAR previews omit trailing padding, so the projected view is not an exact padded-storage display; inspecting never changes that storage. CASTING field symbols use their declared type for supported hex/character reinterpretations. Reference previews stop after eight links or a cycle. Dates use ISO order rather than a user-specific SAP date format. Float fixtures are derived from SAP's scientific type-f formatting rules, with a fixed decimal point; they are not captured SAP debugger output or a claim of exact parity across debugger versions and locales. Bundled constructors must have their runtime names restored by bin/osd.mjs; the tests bundle the runtime and execute that exact startup block. Unknown values and failed formatting keep VS Code's default rendering. The view uses the built-in Node debugger's custom generator options, which js-debug currently marks deprecated. It applies to desktop system and ABAP Unit sessions started by the extension; it does not change Watch expression syntax or provide a browser debugger. Custom child properties are for inspection; edit ABAP values in source rather than using Set Value on the projected children.

Current limits

• Portable AMDP support is limited. HANA-specific SQLScript needs HANA, and some methods are not portable to SQLite.
• Warm rebuild requires upstream transpiler fixes #1900 and #1921 to be released. Until then activation uses the cold build path.
• osd.engine: "osgo" runs the release's Go executable instead of the Node host. It is downloaded on the first start (about 73 MB on Linux x64) from this extension's own release, checked against its .sha256 and kept; it is never part of the VSIX. It serves the services it was built with, so workspace ABAP is not compiled into it, an activation needs a rebuild of osgo, and CHECK/activation need the compiler sidecar it does not download yet. SQLite only; no debugger and no background jobs.
• The Marketplace build has no browser extension entry. The separate web gateway probe remains a development experiment.

The extension is MIT licensed. Bundled dependency declarations and licence review items are in THIRD-PARTY-NOTICES.md inside the VSIX.

Background jobs

osd: Start system also starts the job worker, restarts it after a crash, and stops it with the system or extension. Serving generation changes restart the worker after its active job finishes, with a bounded shutdown wait. No terminal command is needed. osd.jobs.worker defaults to auto; use off to disable it or on to enable it explicitly. Both modes require durable file SQLite. The default osd.database.system=sqlite stores a shared file. Other backends leave the worker stopped and show one message to use file SQLite. The OSD jobs status bar shows idle, running/queued counts, or a stopped worker. Click it to open OSD Jobs in the OSD sidebar. Browse the newest 200 saved runs grouped by status, filter by name/user/date, and expand a job for steps, start condition and duration. Right-click for Open job log, Open output (the API verifies SHA-256), or Copy job key. Log and output tabs are read-only; missing output is reported explicitly. The panel refreshes with the jobs status poll while jobs are active or waiting, retaining its last view while the system is busy or paused. Stopped systems and disabled APIs show a one-line state with Start system. Only imported saved runs are listed; unimported reservations are outside this API, and step variants/users are shown only when recorded. No cancel, repeat or delete actions are included.

Use OSD: Show jobs for a readable OSD: Jobs summary: one line per run, newest first, with its name, state, start time, duration, step/output counts where available, and failure reason. The summary refreshes every two seconds after opening and shows up to 200 recent runs. Show raw job log in the action menu or command palette opens the unchanged worker JSON events and diagnostics in OSD: Jobs. This explicit action switches the channel to raw mode; Show jobs restores summaries. Raw mode streams live events and retains the worker log for this window’s session.

Local ABAP-FS connection

Start your pocket system with osd: Start. With our ABAP-FS fork, branch osd-api, OSD (local) appears without a password prompt. It connects automatically in an empty window, a multi-root window, or a saved/Untitled workspace (workspaceFile is defined). In a single-folder window, a one-time, non-modal Open OSD (local) in ABAP-FS / Not now offer leaves mounting to your explicit click. Mounting reloads that window; OSD remembers that the system was running and starts it automatically on activation. Dismissal and Not now are remembered across windows. Stop withdraws it; a new start uses a fresh token. Passwordless auto-connect requires this fork until API v2 is upstream. Tokens stay in memory and the serving process environment, never settings or files.

The provider sends name: "OSD (local)" and id: "osd-local". The fork at 0e200a2d documents a display name, but its API mount still names the root from the ID, so it currently reads osd-local(ABAP). Fork follow-up: use the provided display name when mounting the workspace folder.

With Marketplace ABAP-FS (API v1 or older), the first start offers Add / Not now once, remembered across windows. Add creates OSD (local) in user abapfs.remote settings with the local URL, client and username, preserving other entries and saving no password. Connect through ABAP-FS and enter any password: the local system accepts it. The settings entry remains after Stop; if a later start chooses another port, update its URL. Existing entries are preserved. This integration covers desktop systems started by OSD; independently started systems and vscode.dev do not receive a token connection.