The .rmdoc notebook package format

Context

So far I have been using the rmapi (https://github.com/ddvk/rmapi) to transfer files to and from my ReMarkable.

I use rmapi version v0.0.29.

When downloading a notebook, a .rmdoc file arrives at my computer. I have found that it’s a ZIP-archive with several files in it.

Illustrative CLI session

This is a transcript from my CLI that provides clues about the .rmdoc format:

tmp $ unzip Sample.rmdoc
Archive:  Sample.rmdoc
 extracting: 62477a1b-de36-4b37-a9cb-d57e595b51e1.content
 extracting: 62477a1b-de36-4b37-a9cb-d57e595b51e1.metadata
 extracting: 62477a1b-de36-4b37-a9cb-d57e595b51e1/5a1aa9a2-b72a-4a0e-9bab-44b179bdd1fa.rm
(.venv) zipfly:~/src/oss/rm-files/sample-files/tmp main
tmp $ tree
.
├── 62477a1b-de36-4b37-a9cb-d57e595b51e1
│   └── 5a1aa9a2-b72a-4a0e-9bab-44b179bdd1fa.rm
├── 62477a1b-de36-4b37-a9cb-d57e595b51e1.content
├── 62477a1b-de36-4b37-a9cb-d57e595b51e1.metadata
└── Sample.rmdoc

2 directories, 4 files
(.venv) zipfly:~/src/oss/rm-files/sample-files/tmp main
tmp $ file 62477a1b-de36-4b37-a9cb-d57e595b51e1/5a1aa9a2-b72a-4a0e-9bab-44b179bdd1fa.rm
62477a1b-de36-4b37-a9cb-d57e595b51e1/5a1aa9a2-b72a-4a0e-9bab-44b179bdd1fa.rm: reMarkable tablet page (v6), 1404 x 1872, 25 layer(s)

tmp $ cat 62477a1b-de36-4b37-a9cb-d57e595b51e1.content

{
"cPages": {
    "lastOpened": {
        "timestamp": "1:1",
        "value": "5a1aa9a2-b72a-4a0e-9bab-44b179bdd1fa"
    },
    "original": {
        "timestamp": "0:0",
        "value": -1
    },
    "pages": [
        {
            "id": "5a1aa9a2-b72a-4a0e-9bab-44b179bdd1fa",
            "idx": {
                "timestamp": "1:2",
                "value": "ba"
            },
            "template": {
                "timestamp": "1:1",
                "value": "seyes"
            }
        }
    ],
    "uuids": [
        {
            "first": "20b88d6c-19b8-5d27-a0b1-0b067ec0a5e9",
            "second": 1
        }
    ]
},
"coverPageNumber": -1,
"customZoomCenterX": 0,
"customZoomCenterY": 936,
"customZoomOrientation": "portrait",
"customZoomPageHeight": 1872,
"customZoomPageWidth": 1404,
"customZoomScale": 1,
"documentMetadata": {
},
"extraMetadata": {
    "LastActiveTool": "primary",
    "LastBallpointColor": "Black",
    "LastBallpointSize": "2",
    "LastBallpointv2Color": "Black",
    "LastBallpointv2Size": "2",
    "LastCalligraphyColor": "Black",
    "LastCalligraphySize": "3",
    "LastEraseSectionColor": "Black",
    "LastEraseSectionSize": "2",
    "LastEraserColor": "Black",
    "LastEraserSize": "2",
    "LastEraserTool": "EraseSection",
    "LastFinelinerv2Color": "Black",
    "LastFinelinerv2Size": "2",
    "LastHighlighterv2Color": "HighlighterGray",
    "LastHighlighterv2Size": "1",
    "LastMarkerv2Color": "Gray",
    "LastMarkerv2Size": "3",
    "LastPaintbrushv2Color": "Black",
    "LastPaintbrushv2Size": "1",
    "LastPen": "Finelinerv2",
    "LastPencilColor": "Black",
    "LastPencilSize": "2",
    "LastPencilv2Color": "Black",
    "LastPencilv2Size": "3",
    "LastSelectionToolColor": "Black",
    "LastSelectionToolSize": "2",
    "LastShadingMarkerColor": "ArgbCode",
    "LastShadingMarkerColorCode": "1075912220",
    "LastShadingMarkerSize": "2",
    "LastSharpPencilv2Color": "Black",
    "LastSharpPencilv2Size": "2",
    "SecondaryCalligraphyColor": "Gray",
    "SecondaryCalligraphySize": "1",
    "SecondaryFinelinerv2Color": "Black",
    "SecondaryFinelinerv2Size": "2",
    "SecondaryHighlighterv2Color": "HighlighterYellow",
    "SecondaryHighlighterv2Size": "1",
    "SecondaryMarkerv2Color": "Black",
    "SecondaryMarkerv2Size": "3",
    "SecondaryPaintbrushv2Color": "Gray",
    "SecondaryPaintbrushv2Size": "1",
    "SecondaryPen": "Highlighterv2",
    "SecondaryPencilv2Color": "Black",
    "SecondaryPencilv2Size": "3",
    "SecondaryShadingMarkerColor": "ArgbCode",
    "SecondaryShadingMarkerColorCode": "1075912220",
    "SecondaryShadingMarkerSize": "3",
    "SecondarySharpPencilv2Color": "Black",
    "SecondarySharpPencilv2Size": "1"
},
"fileType": "notebook",
"fontName": "",
"formatVersion": 2,
"lineHeight": -1,
"margins": 125,
"orientation": "portrait",
"pageCount": 1,
"pageTags": [
],
"sizeInBytes": "20494",
"tags": [
],
"textAlignment": "justify",
"textScale": 1,
"zoomMode": "bestFit"
}

Decision

This information given in the CLI transcript of the last section should provide what’s needed to support the .rmdoc format.

Consequences

Positive/negative outcomes, follow-up tasks, trade-offs.

Positive outcomes

• The format is enclosed in a Zip file.

• Shelling out to the OS file tool will provide some initial information to reverse-engineer the .rm format.

• Transfering a Notebook to the ReMarkable should be easy using the user installed program rmapi.

Trade-offs

Shelling out to OS tools and a custom program will make this program difficult to port to non-posix OS’es.