xmysql : One command to generate REST APIs for any MySql database

Powered by popular node packages : (express, mysql) => { xmysql }

Why this ?

Generating REST APIs for a MySql database which does not follow conventions of frameworks such as rails, django etc is a small adventure that one like to avoid ..

Setup and Usage

npm install -g xmysql

xmysql -h localhost -u mysqlUsername -p mysqlPassword -d databaseName

http://localhost:3000

That is it! Happy hackery!

Features

• Generates API for ANY MySql database
• Serves APIs irrespective of naming conventions of primary keys, foreign keys, tables etc
• CRUD : Usual suspects
• Relations
• Support for composite primary keys
• Pagination
• Sorting
• Column filtering - Fields
• Row filtering - Where
• Group By, Having (as query params)
• Group By, Having (as a separate route)
• Aggregate functions
• Run dynamic queries
• Upload single file
• Upload multiple files
• Download file

Use HTTP clients like Postman or similar tools to invoke REST API calls

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Download node, mysql (setup mysql), sample database - if you haven't on your system.

Root URL

Root URL (localhost:3000/) returns all REST API urls for each table in schema.

CRUD APIs Usual Suspects

• GET       /api/tableName
• POST      /api/tableName
• GET       /api/tableName/:id
• PUT       /api/tableName/:id
• GET       /api/tableName/count
• GET       /api/tableName/exists
• GET       /api/tableName/groupby
• GET       /api/tableName/aggregate
• GET       /api/parentTable/:id/childTable
• DELETE  /api/tableName/:id
• POST     /dynamic

Other APIS

• GET      /api/tableName/describe
• GET      /api/tables

Relational Tables

xmysql identifies foreign key relations automatically and provides GET api.

/api/blogs/103/comments

eg: blogs is parent table and comments is child table. API invocation will result in all comments for blog primary key 103.

Support for composite primary keys

___ (three underscores)

/api/payments/103___JM555205

___ : If there are multiple primary keys - seperate them by three underscores as shown

Pagination

_p & _size

_p indicates page and _size indicates size of response rows

By default 20 records and max of 100 are returned per GET request on a table.

/api/payments?_size=50

/api/payments?_p=2

/api/payments?_p=2&_size=50

Order by / Sorting

ASC

/api/payments?_sort=column1

eg: sorts ascending by column1

DESC

/api/payments?_sort=-column1

eg: sorts descending by column1

Multiple fields in sort

/api/payments?_sort=column1,-column2

eg: sorts ascending by column1 and descending by column2

Column filtering / Fields

/api/payments?_fields=customerNumber,checkNumber

eg: gets only customerNumber and checkNumber in response of each record

/api/payments?_fields=-checkNumber

eg: gets all fields in table row but not checkNumber

Row filtering / Where

Comparison operators

eq  -   '='
ne  -   '!='
gt  -   '>'
gte -   '>='
lt  -   '<'
lte -   '<='

Use of comparison operators

/api/payments?_where=(checkNumber,eq,JM555205)

Logical operators

~or     -   'or'
~and    -   'and'
~xor    -   'xor'

Use of logical operators

eg: simple logical expression

/api/payments?_where=(checkNumber,eq,JM555205)~or(checkNumber,eq,OM314933)

eg: complex logical expression

/api/payments?_where=((checkNumber,eq,JM555205)~or(checkNumber,eq,OM314933))~and(amount,gt,100)

eg: logical expression with sorting(_sort), pagination(_p), column filtering (_fields)

/api/payments?_where=(amount,gte,1000)&_sort=-amount&p=2&&_fields=customerNumber

eg: filter of rows using _where is available for relational route URLs too.

/api/offices/1/employees?_where=(jobTitle,eq,Sales%20Rep)

Group By, Having (as query params)

/api/offices?_groupby=country

eg: SELECT country,count(*) FROM offices GROUP BY country

/api/offices?_groupby=country&_having=(_count,gt,1)

eg: SELECT country,count(1) as _count FROM offices GROUP BY country having _count > 1

Group By, Having (as a seperate route)

/api/offices/groupby?_fields=country

eg: SELECT country,count(*) FROM offices GROUP BY country

/api/offices/groupby?_fields=country,city

eg: SELECT country,city,count(*) FROM offices GROUP BY country,city

/api/offices/groupby?_fields=country,city&_having=(_count,gt,1)

eg: SELECT country,city,count(*) as _count FROM offices GROUP BY country,city having _count > 1

Group By, Order By

/api/offices/groupby?_fields=country,city&sort=city

eg: SELECT country,city,count(*) FROM offices GROUP BY country,city ORDER BY city ASC

/api/offices/groupby?_fields=country,city&sort=city,country

eg: SELECT country,city,count(*) FROM offices GROUP BY country,city ORDER BY city ASC, country ASC

/api/offices/groupby?_fields=country,city&sort=city,-country

eg: SELECT country,city,count(*) FROM offices GROUP BY country,city ORDER BY city ASC, country DESC

Aggregate functions 🎃 😎

http://localhost:3000/api/payments/aggregate?_fields=amount

response body
[
    {
        "min_of_amount": 615.45,
        "max_of_amount": 120166.58,
        "avg_of_amount": 32431.645531,
        "sum_of_amount": 8853839.23,
        "stddev_of_amount": 20958.625377426568,
        "variance_of_amount": 439263977.71130896
    }
]

eg: retrieves all numeric aggregate of a column in a table

http://localhost:3000/api/orderDetails/aggregate?_fields=priceEach,quantityOrdered

response body
[
    {
        "min_of_priceEach": 26.55,
        "max_of_priceEach": 214.3,
        "avg_of_priceEach": 90.769499,
        "sum_of_priceEach": 271945.42,
        "stddev_of_priceEach": 36.576811252187795,
        "variance_of_priceEach": 1337.8631213781719,
        "min_of_quantityOrdered": 6,
        "max_of_quantityOrdered": 97,
        "avg_of_quantityOrdered": 35.219,
        "sum_of_quantityOrdered": 105516,
        "stddev_of_quantityOrdered": 9.832243813502942,
        "variance_of_quantityOrdered": 96.67301840816688
    }
]

eg: retrieves numeric aggregate can be done for multiple columns too

Run dynamic queries

Dynamic queries on a database can be run by POST method to URL localhost:3000/dynamic

This is enabled only when using local mysql server i.e -h localhost or -h 127.0.0.1 option.

Post body takes two fields : query and params.

query: SQL query or SQL prepared query (ones with ?? and ?)

params : parameters for SQL prepared query

POST /dynamic   

    {
        "query": "select * from ?? limit 1,20",
        "params": ["customers"]
    }

Upload single file

POST /upload

Do POST operation on /upload url with multiform 'field' assigned to local file to be uploaded

eg: curl --form file=@/Users/me/Desktop/a.png http://localhost:3000/upload

returns uploaded file name else 'upload failed'

(Note: POSTMAN has issues with file uploading hence examples with curl)

Upload multiple files

POST /uploads

Do POST operation on /uploads url with multiform 'fields' assigned to local files to be uploaded

Notice 's' near /api/uploads and files in below example

eg: curl --form files=@/Users/me/Desktop/a.png --form files=@/Users/me/Desktop/b.png http://localhost:3000/uploads

returns uploaded file names as string

Download file

http://localhost:3000/download?name=fileName

For upload and download of files -> you can specify storage folder using -s option Upload and download apis are available only with local mysql server

When to use ?

• You need just REST APIs without much hassle for (ANY) MySql database.
• You are learning new frontend frameworks and need REST APIs for your MySql database.
• You are working on a demo, hacks etc

When NOT to use ?

• If you are in need of a full blown MVC framework, ACL, Authorisation etc - early days.

Command line options

  Options:

    -V, --version            output the version number
    -h, --host <n>           hostname of mysql
    -d, --database <n>       database schema name
    -u, --user <n>           username of database / root by default
    -p, --password <n>       password of database / empty by default
    -n, --portNumber <n>     port number / 3000 by default
    -s, --storageFolder <n>  storage folder / current working dir by default
    -h, --help               output usage information

  Examples:

    $ xmysql -u username -p password -d databaseSchema

Docker

Simply build with docker build -t xmysql . and run with docker run -p 3000:3000 -d xmysql

The best way for testing is to run mysql in a docker container too and create a docker network, so that xmysql can access the mysql container with a name from docker network.

1. Create network
   • docker network create mynet
2. Start mysql with docker name some-mysql and bind to docker network mynet
   • docker run --name some-mysql -p 3306:3306 --net mynet -e MYSQL_ROOT_PASSWORD=password -d mysql
3. build xmysql container (if not done yet)
   • docker build -t xmysql .
4. run xmysql and set env variable for some-mysql from step 2
   • docker run -p 3000:3000 -d -e DATABASE_HOST=some-mysql --net mynet xmysql

You can also pass the environment variables to a file and use them as an option with docker like docker run --env-file ./env.list -p 3000:3000 --net mynet -d xmysql

environment variables which can be used:

ENV DATABASE_HOST 127.0.0.1
ENV DATABASE_USER root
ENV DATABASE_PASSWORD password
ENV DATABASE_NAME sakila