OneDocument

Read, write, calculate, template and render Word, Excel and PowerPoint documents (OOXML, legacy binary, RTF, ODF) in pure .NET. Not affiliated with Microsoft.

OneDocument is a clean-room document processor for net10.0 that depends only on the .NET base class library and other Recursive AI libraries. It is NativeAOT-, trim- and browser-WebAssembly-friendly: no reflection, no native code, no System.Xml in the document path.

• Lossless models. Document, Workbook and Presentation are views over the file's own markup. Parts you do not touch are written back byte-identical (raw zip entries, never recompressed); edits keep unknown elements, attributes, prefixes, mc:AlternateContent and extLst in order.
• Every layer is public: containers and records, a lazy markup tree, generated typed views of the schemas, the hubs, and the services on top (calculation, templating, layout, operations). The Office, Spreadsheet and Template statics are one line over the model.
• Tolerant reading, typed defects. Damage is repaired where Office repairs it and reported as a located defect (docs/defects.md); resource limits are on by default; nothing touches the network or runs code.
• Conversions say what they lose. Every conversion between formats can return a loss report.

Status: 1.0

The tables below say what the code does and what has been checked, with the note or test that holds each number. A check that could not be run says so and is listed under Gaps; nothing here claims what was not measured. Measurements were taken on the code at the 1.0 freeze.

Samples

Each sample under samples/ is a small console program that generates its own input and runs in CI.

HappyPath runs the introduction's sketch as written, one or two lines per task.

using RecursiveAI.OneDocument;
using RecursiveAI.OneDocument.Documents;
 
using var doc = Document.Open("contract.docx");   // the format comes from the content, never the extension
doc.Paragraphs.First().SetText("Master services agreement");
doc.Save();                                       // atomic; only word/document.xml changes
Office.Convert("contract.docx", "contract.pdf");  // needs the Rendering package (or the All metapackage)

The Office statics find the readers and writers of every kind package the application references; no registration call is needed (each package registers itself into the referencing C# project at build time, with no reflection). A format whose package is not referenced raises FormatNotAvailableException naming it. Referencing one kind package (say .Spreadsheets) is enough for that kind and pulls in no other. In a project that is not C# or that sets <OneDocumentAutoRegister>false</OneDocumentAutoRegister>, call DocumentFormats.Register(FormatRegistry.Default) (and SpreadsheetFormats, PresentationFormats, RenderingFormats) once at start-up; docs/contracts.md has the table. Coming from another library? See docs/migration/.

Formats

"Untouched round trip" is open then save with no edit: for the OOXML, ODF and XLSB families every part is written back as stored; the other formats are rebuilt from the model and say so in the loss report. Details and defect codes are in the linked notes.

Encrypted files open when OpenContext.Password is supplied: OOXML Agile and Standard, RC4, RC4 CryptoAPI and XOR for the legacy formats (docs/encryption.md). Excel, Word and PowerPoint open our RC4 CryptoAPI XLS output, and the Agile and RC4 files other applications wrote, with the same password (9 of 10 fixtures; the XOR one is the exception).

Checks

Numbers come from the committed note or test named in the last column. Office-oracle checks (Word, Excel and PowerPoint opening our output without a repair prompt, Office's own result for the same operation, the layout differential) ran on desktop Office 16.0.20527 for the 1.0 gate: results, floors and the open items are in docs/office-oracle-1.0.md. The remaining requests under testdata/ are listed there as not run.

Operations

Gaps

Stated here so they are not found by surprise.

• Encrypted output. Encrypted files are written only for XLS (RC4 CryptoAPI). Agile OOXML and ODF encryption on write wait for the Cryptography package.
• Cryptography package. RecursiveAI.OneDocument.Cryptography (signatures, encryption on write) has no content yet and is not part of the All metapackage.
• Browser. WebAssembly has no Aes or MD5, so opening Agile or Standard encrypted OOXML and RC4-MD5 files there raises OfficeUnsupportedException. RC4 CryptoAPI and XOR files read normally (docs/platforms.md). The XOR reader's array-index rule rests on LibreOffice alone: Excel does not open our XOR test file, so that scheme is unconfirmed against Office (docs/office-oracle-1.0.md).
• Document Inspector agreement. Office's object model exposes only some inspectors (Word 5, Excel 5, PowerPoint 4). Comments, revisions, document properties and personal information, embedded documents, macros and links cannot be asked, so agreement for those categories was not measured; our own re-inspection finds nothing left in sanitised output (docs/office-oracle-1.0.md, docs/sanitize.md).
• Accessibility Checker. Pending: Office has no automation for it, so our results are checked against the published rule set only (docs/accessibility.md).
• PDF/A-2a. In the veraPDF run, 19 of 20 DOCX and 15 of 16 PPTX pass; the failures are one rule (6.2.11.7.3, a private-use character without ActualText) in the PDF writer (docs/gates-1.0.md §6).
• Calculation. Recalculation reproduces cached values over each corpus at the floors in the Checks table; the mismatches fall in named classes (precision beyond 9 digits, volatile functions and what depends on them, references into other workbooks, legacy references the converter leaves as #REF!, XLM macro functions, and unexplained cases), listed per set in docs/gates-1.0.md §5. ODS-sourced workbooks reproduce 65.3% and were not rerun after the fixes. The per-function grids against Excel disagree on 6.7% of function rows, 15.5% of financial and 12.0% of engineering rows (distribution inverses on boundary arguments, text conversions, coupon-date functions, iteration limits, error kinds on out-of-range arguments); GETPIVOTDATA over some cached pivots, SUBTOTAL with an autofilter and external references in BIFF are open.
• Schema validation. On four already-invalid worksheets in the public corpus, the validator counts one more xr:uid error after our rewrite than before; the attribute is on the original too and its cause was not established (docs/gates-1.0.md §2).
• ODS. No forward cursor: ODS reads through the model.
• Office opens ODS. Excel does not open the ODS files we write (they validate against the ODF 1.3 schema and LibreOffice opens them); information, not bisected.
• Formula text is en-US and invariant only; localized function names are not supported.
• DOC and PPT are read-only. Word 6/95 and BIFF2 to BIFF5 layouts come from observed files, not a specification.
• Metafiles. Drawn as vector content where the interpreter supports the records; custom pen caps, line-end anchors, colour matrices and text clipping to a string's rectangle are not drawn, and some raster-operation cases fall back to a bitmap (docs/metafiles.md).
• Output formats. PDF, and PNG, JPEG, TIFF, WebP and SVG pages (PageExporter; SaveAs and Office.Convert write the first page, or every page for TIFF). HTML, Markdown and text export are on the hubs.
• Rendering fidelity. Page layout is implemented from the Word, PowerPoint and Excel rules in docs/layout*.md; how closely it matches Office is measured in docs/office-oracle-1.0.md (Word 16.0.20527, generated cases), and the layout notes list the places still to be checked against Word.
• Not executed. Macros, OLE payloads, Power Query, the Data Model and Solver are carried and (for VBA) listed or removed, never run.

Packages

Building

dotnet build OneDocument.slnx
dotnet test --solution OneDocument.slnx
build/ci.sh            # restore, build, test, samples, NativeAOT smoke, WebAssembly smoke, pack

The public surface of every library assembly is frozen in src/<Project>/PublicAPI.Shipped.txt, checked on each build by the public-API analyzer (build-only, nothing flows into the packages): a public type or member added, removed or changed without a listing edit fails the build. List an intended change in PublicAPI.Unshipped.txt (tools/api/update-public-api.py --unshipped does it); a release moves those lines into Shipped.

The .NET SDK version is pinned in global.json. Build output goes to artifacts/ (ignored by git); set ONEDOCUMENT_ARTIFACTS to put it elsewhere.

Layout

src/ packages, samples/ runnable examples, tests/ unit tests, tools/ harness and generator tools, fuzz/ libFuzzer targets, bench/ benchmarks, smoke/ NativeAOT and WebAssembly smoke apps, docs/ normative notes (index in docs/README.md).

Licence

MIT OR Apache-2.0, © Recursive AI, LLC. See LICENSE-MIT, LICENSE-APACHE and THIRD-PARTY-NOTICES.md.

OneDocument is not affiliated with Microsoft or with any other product or company named OneDocument. Word, Excel and PowerPoint are Microsoft product names used here only to describe the formats.