hapi-csv

What

Converts the response to csv based on the Joi response schema when the Accept header includes text/csv or application/csv or the requested route ends with .csv. Converts the response to xlsx (Excel) with the enableExcel option when the Accept header includes application/vnd.openxmlformats-officedocument.spreadsheetml.sheet or the requested route ends with .xlsx.

How

npm install --save hapi-csv

Register the hapi-csv plugin on the server

await server.register({
    plugin: require('hapi-csv'),
    options: {
        maximumElementsInArray: 5,
        separator: ',',
        resultKey: 'items'
    }
});

When you have a route on which a response schema is defined, like in the example below, the plugin will convert the response to csv when the Accept header includes text/csv or application/csv or the requested route ends with .csv

const routes = [{
    method: 'GET',
    path: '/users',
    handler: Users.getAll,
    config: {
        response: {
            schema: Joi.object().keys({
                first_name: Joi.string(),
                last_name: Joi.string(),
                age: Joi.number()
            })
        }
    }
}]

Either do GET /users with header Accept: text/csv or Accept: application/csv. Or do GET /users.csv. The header approach is preferred. When the request path ends in .csv the .csv part will be stripped and the accept header will be set to text/csv.

Currently the Content-Disposition header is set to attachment; by default since this plugin is intended for exporting purposes, if this hinders you just let us know.

Paginated responses

To handle typical pagination responses pass the resultKey option. The value is the top level key you want to convert to csv.

// paginated response
{
    "page": 1,
    "items": [
        { "name": "Anton", "age": 22 },
        { "name": "Lisa", "age": 25 }
    ]
}

await server.register({
    plugin: require('hapi-csv'),
    options: {
        resultKey: 'items' // We only want the `items` in csv
    }
});

Dynamic schemas

hapi-csv supports dynamic response schemas as well. Imagine one of your property's schema is dynamic but you still want to export the value of it to csv. You can tell hapi-csv to translate a given key on the fly when it is converting the response to csv (onPreResponse). On the route config set the plugin config to an object like

{
    'keyPath': async (request) => {

        return JoiSchema;
    }
}

The key is the path of the property you want to resolve dynamically. E.g.

Joi.object().keys({
    a: Joi.object(),
    b: Joi.object().keys({
        c: Joi.object()
    })
})

If you want to convert a the key would be a. For c it would be b.c.

Full example:

server.route([{
    ...,
    config: {
        ...,
        response: {
            schema: Joi.object().keys({
                first_name: Joi.string(),
                last_name: Joi.string(),
                age: Joi.number(),
                custom: Joi.object(),
                deepCustom: Joi.object().keys({
                    deepestCustom: Joi.object()
                })
            })
        },
        plugins: {
            'hapi-csv': {
                'custom': (request) => {

                    const schema = Joi.object().keys({
                        id: Joi.number(),
                        name: Joi.string()
                    });

                    return schema;
                },
                'deepCustom.deepestCustom': (request) => {

                    throw new Error('nope');
                }
            }
        }
     }
 ])

Excel

You can also enable Excel conversion. It will convert the response to xlsx (Excel) when the Accept header includes application/vnd.openxmlformats-officedocument.spreadsheetml.sheet or the requested route ends with .xlsx.

await server.register({
    plugin: require('hapi-csv'),
    options: {
        enableExcel: true,
        excelWriteOptions: { /* compression: false */ }
    }
});

excelWriteOptions takes anything for https://github.com/SheetJS/js-xlsx#writing-options