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+
+Mapping JSON to spreadsheet
+===========================
+
+This tutorial covers how to map JSON document to a spreadsheet document, very
+similar to what we covered in :ref:`this tutorial <mapping-xml-to-ss>`
+where we illustrated how to map XML document to a spreadsheet document.
+
+Throughout this tutorial, we will be using :download:`this sample JSON document <example.json>`
+to illustrate how to achieve it using the ``orcus-json`` command. The structure
+of this tutorial will be similar to the structure of the XML mapping counterpart,
+since the steps are very similar.
+
+Examining the structure of the input JSON document
+--------------------------------------------------
+
+Let's first take a look at the sample JSON document:
+
+.. code-block:: javascript
+
+ [
+ {
+ "id": 1,
+ "name": [
+ "Tab",
+ "Limpenny"
+ ],
+ "active": true,
+ "gender": "Male",
+ "language": "Kazakh"
+ },
+ {
+ "id": 2,
+ "name": [
+ "Manda",
+ "Hadgraft"
+ ],
+ "active": false,
+ "gender": "Female",
+ "language": "Bislama"
+ },
+ {
+ "id": 3,
+ "name": [
+ "Mickie",
+ "Boreham"
+ ],
+ "active": false,
+ "gender": "Male",
+ "language": "Swahili"
+ },
+
+ ...
+
+This is essentially the same content as the XML sample document we used in the
+:ref:`last tutorial <mapping-xml-to-ss>` but re-formatted in JSON.
+
+Let run the following command:
+
+.. code-block::
+
+ orcus-json --mode structure example.json
+
+to analyze the structure of this JSON document. The command will generate the
+following output:
+
+.. code-block::
+
+ $array[20].object(*)['active'].value
+ $array[20].object(*)['gender'].value
+ $array[20].object(*)['id'].value
+ $array[20].object(*)['language'].value
+ $array[20].object(*)['name'].array[2].value[0,1]
+
+This structure output resembles a variant of JSONPath but some modifications
+are applied. It has the following characteristics:
+
+* The ``$`` symbol represents the root of the structure.
+* Array node takes the form of either ``array[N]``, where the value of ``N``
+ represents the number of elements.
+* Object node takes the form of ``object['key']``.
+* Value node, which is always a leaf node, is represented by ``value`` except
+ when the leaf node is an array containing values, it takes the form of ``value[0,1,2,...]``.
+* The ``.`` symbols represent the node boundaries.
+* The ``(*)`` symbols represent recurring nodes, which can be either array or
+ object.
+
+Auto-mapping the JSON document
+------------------------------
+
+Let's map this JSON document to a spreadsheet document by running:
+
+.. code-block::
+
+ orcus-json --mode map -o out -f flat example.json
+
+This is very similar to what we did in the XML mapping tutorial, except that
+the command used is ``orcus-json`` and the input file is ``example.json``.
+This will create file named ``out/range-0.txt`` which contains the following:
+
+.. code-block::
+
+ ---
+ Sheet name: range-0
+ rows: 21 cols: 6
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | id | field 0 | field 1 | active | gender | language |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 1 [v] | Tab | Limpenny | true [b] | Male | Kazakh |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 2 [v] | Manda | Hadgraft | false [b] | Female | Bislama |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 3 [v] | Mickie | Boreham | false [b] | Male | Swahili |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 4 [v] | Celinka | Brookfield | false [b] | Female | Gagauz |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 5 [v] | Muffin | Bleas | false [b] | Female | Hiri Motu |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 6 [v] | Jackelyn | Crumb | false [b] | Female | Northern Sotho |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 7 [v] | Tessie | Hollingsbee | true [b] | Female | Fijian |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 8 [v] | Yank | Wernham | false [b] | Male | Tok Pisin |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 9 [v] | Brendan | Lello | true [b] | Male | Fijian |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 10 [v] | Arabel | Rigg | false [b] | Female | Kyrgyz |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 11 [v] | Carolann | McElory | false [b] | Female | Pashto |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 12 [v] | Gasparo | Flack | false [b] | Male | Telugu |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 13 [v] | Eolanda | Polendine | false [b] | Female | Kashmiri |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 14 [v] | Brock | McCaw | false [b] | Male | Tsonga |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 15 [v] | Wenda | Espinas | false [b] | Female | Bulgarian |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 16 [v] | Zachary | Banane | true [b] | Male | Persian |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 17 [v] | Sallyanne | Mengue | false [b] | Female | Latvian |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 18 [v] | Elizabet | Hoofe | true [b] | Female | Tswana |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 19 [v] | Alastair | Hutchence | true [b] | Male | Ndebele |
+ +--------+-----------+-------------+-----------+--------+----------------+
+ | 20 [v] | Minor | Worland | true [b] | Male | Dutch |
+ +--------+-----------+-------------+-----------+--------+----------------+
+
+Again, this is very similar to what we saw in the XML-mapping example. Note
+that cell values with ``[v]`` and ``[b]`` indicate numeric and boolean values,
+respectively. Cells with no suffixes are string cells.
+
+Custom-mapping using map file
+-----------------------------
+
+This process is also very similar to the process we followed for XML mapping.
+We first auto-generate a map file, modify it, and use it to do the mapping again.
+Since there isn't much difference between XML mapping and JSON mapping, let's
+just go through this very quick.
+
+First step is to generate a map file for the auto-detected range by running:
+
+.. code-block::
+
+ orcus-json --mode map-gen -o map.json example.json
+
+which will write the mapping rules to ``map.json`` file. When you open the generated
+map file, you will see something like the following:
+
+.. code-block:: javascript
+
+ {
+ "sheets": [
+ "range-0"
+ ],
+ "ranges": [
+ {
+ "sheet": "range-0",
+ "row": 0,
+ "column": 0,
+ "row-header": true,
+ "fields": [
+ {
+ "path": "$[]['id']"
+ },
+ {
+ "path": "$[]['name'][0]"
+ },
+ {
+ "path": "$[]['name'][1]"
+ },
+ {
+ "path": "$[]['active']"
+ },
+ {
+ "path": "$[]['gender']"
+ },
+ {
+ "path": "$[]['language']"
+ }
+ ],
+ "row-groups": [
+ {
+ "path": "$"
+ }
+ ]
+ }
+ ]
+ }
+
+The structure and content of the map file should look similar to the XML counterpart,
+except that it is now in JSON format, and the paths are expressed in slightly
+modified JSONPath bracket notation, where ``[]`` represents an array node with
+no position specified.
+
+Now that we have a map file, let's modify this and use it to do the mapping once
+again. Just like the XML mapping example, we are going to:
+
+* insert two blank rows above,
+* drop the ``id`` and ``active`` fields,
+* specify labels for the fields, and
+* change the sheet name from ``range-0`` to ``My Data``.
+
+This is what we've come up with:
+
+.. code-block:: javascript
+
+ {
+ "sheets": [
+ "My Data"
+ ],
+ "ranges": [
+ {
+ "sheet": "My Data",
+ "row": 2,
+ "column": 0,
+ "row-header": true,
+ "fields": [
+ {
+ "path": "$[]['name'][0]", "label": "First Name"
+ },
+ {
+ "path": "$[]['name'][1]", "label": "Last Name"
+ },
+ {
+ "path": "$[]['gender']", "label": "Gender"
+ },
+ {
+ "path": "$[]['language']", "label": "Language"
+ }
+ ],
+ "row-groups": [
+ {
+ "path": "$"
+ }
+ ]
+ }
+ ]
+ }
+
+We'll save this file as ``map-modified.json``, and pass it to the ``orcus-json``
+command via ``--map`` or ``-m`` option:
+
+.. code-block::
+
+ orcus-json --mode map -o out -f flat -m map-modified.json example.json
+
+Let's check the output in ``out/My Data.txt`` and see what it contains:
+
+.. code-block::
+
+ ---
+ Sheet name: My Data
+ rows: 23 cols: 4
+ +------------+-------------+--------+----------------+
+ | | | | |
+ +------------+-------------+--------+----------------+
+ | | | | |
+ +------------+-------------+--------+----------------+
+ | First Name | Last Name | Gender | Language |
+ +------------+-------------+--------+----------------+
+ | Tab | Limpenny | Male | Kazakh |
+ +------------+-------------+--------+----------------+
+ | Manda | Hadgraft | Female | Bislama |
+ +------------+-------------+--------+----------------+
+ | Mickie | Boreham | Male | Swahili |
+ +------------+-------------+--------+----------------+
+ | Celinka | Brookfield | Female | Gagauz |
+ +------------+-------------+--------+----------------+
+ | Muffin | Bleas | Female | Hiri Motu |
+ +------------+-------------+--------+----------------+
+ | Jackelyn | Crumb | Female | Northern Sotho |
+ +------------+-------------+--------+----------------+
+ | Tessie | Hollingsbee | Female | Fijian |
+ +------------+-------------+--------+----------------+
+ | Yank | Wernham | Male | Tok Pisin |
+ +------------+-------------+--------+----------------+
+ | Brendan | Lello | Male | Fijian |
+ +------------+-------------+--------+----------------+
+ | Arabel | Rigg | Female | Kyrgyz |
+ +------------+-------------+--------+----------------+
+ | Carolann | McElory | Female | Pashto |
+ +------------+-------------+--------+----------------+
+ | Gasparo | Flack | Male | Telugu |
+ +------------+-------------+--------+----------------+
+ | Eolanda | Polendine | Female | Kashmiri |
+ +------------+-------------+--------+----------------+
+ | Brock | McCaw | Male | Tsonga |
+ +------------+-------------+--------+----------------+
+ | Wenda | Espinas | Female | Bulgarian |
+ +------------+-------------+--------+----------------+
+ | Zachary | Banane | Male | Persian |
+ +------------+-------------+--------+----------------+
+ | Sallyanne | Mengue | Female | Latvian |
+ +------------+-------------+--------+----------------+
+ | Elizabet | Hoofe | Female | Tswana |
+ +------------+-------------+--------+----------------+
+ | Alastair | Hutchence | Male | Ndebele |
+ +------------+-------------+--------+----------------+
+ | Minor | Worland | Male | Dutch |
+ +------------+-------------+--------+----------------+
+
+The ``id`` and ``active`` fields are gone, the remaining fields have custom
+labels we specified, and there are two blank rows above. It appears that all
+the changes we have intended have been properly applied.
generated by cgit v1.2.3 (git 2.39.1) at 2025-07-11 02:56:42 +0000