bookshelf-jsonapi-params

bookshelf-jsonapi-params

The JSON API spec defines standard parameters to be used when refining result sets via filtering, sparse fieldsets, paging, etc. This Bookshelf.js plugin adds a method to your models that can be called to automatically refine the results of your queries based on the aforementioned parameters.

Installation

Install the package via npm:

$ npm i --save bookshelf-jsonapi-params

Usage

Require and register the bookshelf-jsonapi-params plugin:

const bookshelf = require('bookshelf')(knex);
const jsonApiParams = require('bookshelf-jsonapi-params');

bookshelf.plugin(jsonApiParams);

After the plugin has been registered, the fetchJsonApi method can be called on your model or collection. Here's an example:

// Please see the API for more information
// on available options
const options = {
    fields: {
        person: ['firstName', 'lastName']
    },
    page: {
        limit: 10
    },
    sort: ['-lastName']
};

// Returns a list of people
Person
    .forge()
    .fetchJsonApi(options)
    .then((result) => {
        return result;
    });

The above example would yield something like the following when transformed to JSON API:

"data": [
    {
      "type": "person",
      "id": "1",
      "attributes": {
        "firstName": "Cookie",
        "lastName": "Monster"
    },
    {
      "type": "person",
      "id": "1",
      "attributes": {
        "firstName": "Baby",
        "lastName": "Bop"
    }
      ...
      [8 more results]
]

Note that only the firstName and lastName attributes are returned, the results are ordered by lastName descending, and only 10 results were returned.

A Note on Returning a Collection vs Resource

If you're returning a single resource from a call such as GET /customers/1, make sure to pass false as the second parameter to fetchJsonApi. See this issue for more information/reasoning.

API

fetchJsonApi(options, isCollection, type, additionalQuery) - calling fetchJsonApi with no options is just like a plain call to Model#fetch or Model#fetchAll. Note that in addition to the options below, you may also pass anything you can pass to Model#fetch or Model#fetchAll.

---

The first parameter options, is passed in as an object that can have the following properties.

{
    filter: {
        // Available filter objects
        or: <filter>[],
        and: <filter>[],
        gt: {},
        gte: {},
        lt: {},
        lte: {},
        not: {},
        like: {},
        'person.age': 25
    },
    fields: {
        person: ['name'],
        pet: ['name']
    },
    include: ['pet'],
    sort: ['name'],
}

filter

Filter is passed in as an object and filters a result set based specific field. Example: /pets?filter[name]=max would only return pets named max. Keywords can be added to filters to give more control over the results. Example: /pets?filterType[like][pet]=ax would only return pets that have "ax" in their name. The supported types are "like", "not", "lt", "lte", "gt", and "gte". Both "like" and "not" support multiple values by comma separation. Also, if your data has a string with a comma, you can filter for that comma by escaping the character with two backslashes. NOTE: This is not supported by JSON API spec.

You can combine multiple filter by passing "or" filter key with array of filter objects. For example:

    filter: {
        or: [
            {
                like: {
                    'pet.toy.type': 'skat'
                }
            },
            {
                type: 'monster'
            }
        ]
    },

will return all objects with "type" equal to "monster" or "type" property of relation pet.toy similar to "skat".

If you need to use more than one or filter, such as (a || b) && (c || d), you can use the "and" field and provide multiple filter objects that contain "or".

    filter: {
        and: [
            {
                or: [
                    {
                        like: {
                            'pet.toy.type': 'skat'
                        }
                    },
                    {
                        type: 'monster'
                    }
                ]
            },
            {
                or: [
                    {
                        age: 70
                    },
                    {
                        gender: 'f'
                    }
                ]
            }
        ] 
    },

This can also be useful in conjunction the "like" filter, since by default if you provide multiple values for a field, it will "or" them together.

    filter: {
        and: [
            {
                like: {
                   name: 'ba'
                }
            },
            {
                like: {
                    name: 'ey'
                }
            }
        ] 
    },

fields

Fields is passed in as an object and selects desired columns from your base table and also relationships. Example: /pets?fields[pets]=name would return pet records with only the name field rather than every field. If there is an included relationship such as /pets?include=owner, fields can be provided to return only desired columns from that relationship /pets?include=owner&fields[owner]=firstName. Note: you may use aggregate functions such as /pets?fields[pets]=count(id). Aggregated functions are not supported for relationship fields or json fields. Supported aggregate functions are "count", "sum", "avg", "max", "min".

include

Passed in as an array of strings, and gets passed through to Bookshelf as withRelated. Returns relationships as part of the payload. Example: /pets?include=owner would return the pet record in addition to the full record of its owner. Note: you may override an include parameter with your own Knex function rather than just a string representing the relationship name.

page

Page can be an object or false. This paginates the result set. Example: /pets?page[limit]=25&page[offset]=0 would return the first 25 records. page and pageSize are also supported. If you've passed default pagination parameters to the plugin, but would like to disable paging on a specific call, just set page to false.

sort

Passed in as an array of strings. Sorts the result set by specific fields. Example: /pets?sort=-weight,birthDate would return the records sorted by weight descending, then birthDate ascending. You can also sort your list by a field on a relationship, /pet?sort=owner.firstName

group

Passed in as an array string. Use it with fields param to group your results. Example: /pets?fields[pets]=avg(age),gender&group=gender would return return the average age of pets per gender. NOTE: This is not supported by JSON API spec.

---

isCollection - by default, internal calls will be made to fetchAll. If you're returning a single resource, set isCollection to false.

---

type - by default, the JSON API resource type will be set using the tableName defined in your Bookshelf model. If your resource type is different, you can pass the resource type into fetchJsonApi directly.

---

additionalQuery - allows you to modify the query builder prior to to execution of the query. This must be a function that takes in the knex Query Builder object. For example:

fetchJsonApi(options, isCollection, type, (qb) => {
    qb.whereRaw('extract(year from date)=2018');
});

---

Postgres JSONB Column Support

JSONB columns can be filtered, sorted, and selected. The API is mostly the same, an additional character will be used to specify where a json column is, this will be a colon :

To create an equality filter on a json column:

filter: {
    'metaData:prop1': value
}

Relational filtering is also supported with JSONB columns:

filter: {
    'relation.metaData:prop1': value
}

Filter multiple nested objects in the json field with a contains filter:

filter: {
    like: {
        'relation.metaData:obj1.prop1': value
    }
}

You must also specify the type of a property split by a second :, if filtering by gt, lt, gte, or lte

Available types are numeric, date, and timestamp. Leaving the type out will default to a string.

filter: {
    gt: {
        'rel.metaData:obj1.prop2:numeric': 60
    }
}

filter: {
    gt: {
        'rel.metaData:obj1.prop3:date': 01-01-2019
    }
}

filter: {
    gt: {
        'rel.metaData:obj1.prop4:timestamp': 01-01-2019:00:00:00
    }
}

JSONB syntax can be used in filter, fields, and sort. It currently does not support aggregate functions and group

Pagination and Sorting

Under the hood, this plugin uses the excellent bookshelf-page plugin. Please see the available options that can be passed in via the page parameter.

Default Pagination Parameters

If you'd like your result sets to be paginated by default without having to add pagination options to each call, you can set the default pagination parameters when registering the plugin:

bookshelf.plugin(jsonApiParams, {
    pagination: { limit: 25 }
});

Note: pagination options passed into the fetchJsonApi will override the defaults.

Default null string

If provided with the string 'null' as a filter value, it will be interpretted as the value null when determining what to filter. This is because in a URL, you can not give the value null, it is represented as a string, since a url is a string. This null string can be overrided to a string of your chosing if you need to filter by the literal string 'null'.

bookshelf.plugin(jsonApiParams, {
    nullString: '_null'
});

Parsing URL Parameters

You can obviously parse all of the URL parameters yourself, but I would highly recommend using the fantastic node-jsonapi-query-parser module to handle this for you. The object produced by this module can be passed directly to this plugin without modification.

Transforming Bookshelf Models to JSON API

Once you have your Bookshelf model, how do you transform it to a JSON API payload? I'd recommend checking out our json-api-serializer module, which will allow you automatically transform your Bookshelf model to a JSON API-compliant payload.

License

MIT