Offer 'Raw Data' format besides 'Tabular View'

Work in progress.

Attached patch offers besides Tabular view:

• Raw data (JSON)
• Raw data (JSON) with header values as keys (if not empty)

Example (in pretty print)

Tabular view

Raw data (JSON)

{
    "caption": "",
    "tabledata": {
        "row_0": {
            "col_0": "A",
            "col_1": "B",
            "col_2": "C"
        },
        "row_1": {
            "col_0": "11",
            "col_1": "12",
            "col_2": "13"
        },
        "row_2": {
            "col_0": "21",
            "col_1": "22",
            "col_2": "23"
        }
    }
}

Raw data (JSON) with header values as keys (if not empty)

{
    "caption": "",
    "tabledata": {
        "row_1": {
            "A": "11",
            "B": "12",
            "C": "13"
        },
        "row_2": {
            "A": "21",
            "B": "22",
            "C": "23"
        }
    }
}

 
If a header value is empty the original key is used. If for example in table above the column header value "C" would be empty then "col_2" would be used as key for that column.

{
    "caption": "",
    "tabledata": {
        "row_1": {
            "A": "11",
            "B": "12",
            "col_2": "13"
        },
        "row_2": {
            "A": "21",
            "B": "22",
            "col_2": "23"
        }
    }
}

Note

We only have pretty print output if on a node page thus in e.g. a View it will be without indentation and line breaks. Usually you would however only use the JSON display in a View capable of serving JSON of through the Services module and still use the Tabular view on the node page. That's why when in JSON mode options like 'Hide header' and 'CSV export' won't have effect.

Solving #2841782: Move display related settings from manage fields to manage display will become more relevant.

Added another display mode 'Raw data (JSON) with header and first column values as keys (if not empty)'. This gives us complete control over the used keys in the JSON on all levels.

Example (in pretty print

Tabular view

Raw data (JSON) with header and first column values as keys (if not empty)

{
    "caption": "",
    "tabledata": {
        "First": {
            "A": "11",
            "B": "12",
            "C": "13"
        },
        "Second": {
            "A": "21",
            "B": "22",
            "C": "23"
        },
        "row_3": {
            "A": "31",
            "B": "32",
            "C": "33"
        }
    }
}

Modified the last added display mode to 'Raw data (JSON) with field label, header and first column values as keys (if not empty)'. This gives us even control over the used top level key.

Furthermore is displays the caption only if not empty (for all Raw JSON displays).

{
    "Table": {
        "First": {
            "A": "11",
            "B": "12",
            "C": "13"
        },
        "Second": {
            "A": "21",
            "B": "22",
            "C": "23"
        },
        "row_3": {
            "A": "31",
            "B": "32",
            "C": "33"
        }
    }
}

To avoid confusion it is recommended to show a notification to the user informing the exception.

I agree.

Avoid informal writing (use 'a table' instead of 'your table').

With an empty table:

Warning: Invalid argument supplied for foreach() in tablefield_field_formatter_view() (line 525 of /sites/all/modules/contrib/tablefield/tablefield.module).

To wrap in a conditional, also in the other view mode (line 480).

Patch additions:

• Skip processing is the table field is empty.
• Show the caption field in the JSON even if empty (improves consistency of the expected output).
• Add a separating comma for multi-value table field to have valid JSON.
• Put a multi-value table field in the same
  

   tags instead of each one separate.

Against latest dev.

Instead of having 3 different view modes for raw JSON data we extended only one with different display options. The result is cleaner and shorter code while enhancing the user experience.

Furthermore we introduced the option to:

• display only tabledata (no caption) so that the JSON is not unnecessary nested if not needed
• have a vertical header (swap columns and rows).

The latter is especially handy when dealing with long lists of key-value pairs that would otherwise be forced to be orientated horizontally resulting in a horizontal scrollbar, worsening the user experience. The setting is there but the feature of swapping should still be built.

Added row-column swap option.

View mode:

Edit mode:

Display options:

Thanks for the thorough review.

Compare D8 (with just one option) with D7 below:

Needed would be probably also a D8 version of the Themeless module.