pREST
Serve a RESTful API from any PostgreSQL database
Postgres version
Problem
There is the PostgREST written in haskell, keep a haskell software in production is not easy job, with this need that was born the pREST.
Docker
https://hub.docker.com/r/nuveo/prest/
docker run -e PREST_HTTP_PORT=3000 \
-e PREST_PG_HOST=127.0.0.1 \
-e PREST_PG_USER=postgres \
-e PREST_PG_PASS=pass \
nuveo/prest:0.1
- 0.1 (stable)
- lastest (developer)
Install
go get github.com/nuveo/prest
Run
Params:
- PREST_HTTP_PORT (default 3000)
- PREST_PG_HOST (default 127.0.0.1)
- PREST_PG_USER
- PREST_PG_PASS
- PREST_PG_DATABASE
- PREST_PG_PORT (default 5432)
- PREST_JWT_KEY
PREST_PG_USER=postgres PREST_PG_DATABASE=prest PREST_PG_PORT=5432 PREST_HTTP_PORT=3010 prest # Binary installed
Migrations
--url
and --path
flags are optional if pREST configurations already set
# env var for migrations directory
PREST_MIGRATIONS
# create new migration file in path
prest migrate --url driver://url --path ./migrations create migration_file_xyz
# apply all available migrations
prest migrate --url driver://url --path ./migrations up
# roll back all migrations
prest migrate --url driver://url --path ./migrations down
# roll back the most recently applied migration, then run it again.
prest migrate --url driver://url --path ./migrations redo
# run down and then up command
prest migrate --url driver://url --path ./migrations reset
# show the current migration version
prest migrate --url driver://url --path ./migrations version
# apply the next n migrations
prest migrate --url driver://url --path ./migrations next +1
prest migrate --url driver://url --path ./migrations next +2
prest migrate --url driver://url --path ./migrations next +n
# roll back the previous n migrations
prest migrate --url driver://url --path ./migrations next -1
prest migrate --url driver://url --path ./migrations next -2
prest migrate --url driver://url --path ./migrations next -n
# go to specific migration
prest migrate --url driver://url --path ./migrations goto 1
prest migrate --url driver://url --path ./migrations goto 10
prest migrate --url driver://url --path ./migrations goto v
TOML
Optionally the pREST can be configured by TOML file
- Set
PREST_CONF
environment variable with file path
migrations = "./migrations"
[http]
port = 6000
[jwt]
key = "secret"
[pg]
host = "127.0.0.1"
user = "postgres"
pass = "mypass"
port = 5432
database = "prest"
API's
HEADER:
- JWT middleware is enable by default. To disable JWT need to run pREST in debug mode
Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiYWRtaW4iOnRydWV9.TJVA95OrM7E2cBab30RMHrHDcEfxjoYZgeFONFh7HgQ
Debug Mode
- Set environment variable
PREST_DEBUG
PREST_DEBUG=true
Filter (WHERE)
GET /DATABASE/SCHEMA/TABLE?FIELD=$eq.VALUE
Query Operators:
Name |
Description |
$eq |
Matches values that are equal to a specified value. |
$gt |
Matches values that are greater than a specified value. |
$gte |
Matches values that are greater than or equal to a specified value. |
$lt |
Matches values that are less than a specified value. |
$lte |
Matches values that are less than or equal to a specified value. |
$ne |
Matches all values that are not equal to a specified value. |
$in |
Matches any of the values specified in an array. |
$nin |
Matches none of the values specified in an array. |
$null |
Matches if field is null |
$notnull |
Matches if field is not null |
Filter (WHERE) with JSONb field
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE?FIELD->>JSONFIELD:jsonb=VALUE (filter)
Select - GET
http://127.0.0.1:8000/databases (show all databases)
http://127.0.0.1:8000/databases?_count=* (count all databases)
http://127.0.0.1:8000/databases?_renderer=xml (JSON by default)
http://127.0.0.1:8000/schemas (show all schemas)
http://127.0.0.1:8000/schemas?_count=* (count all schemas)
http://127.0.0.1:8000/schemas?_renderer=xml (JSON by default)
http://127.0.0.1:8000/tables (show all tables)
http://127.0.0.1:8000/tables?_renderer=xml (JSON by default)
http://127.0.0.1:8000/DATABASE/SCHEMA (show all tables, find by schema)
http://127.0.0.1:8000/DATABASE/SCHEMA?_renderer=xml (JSON by default)
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE (show all rows, find by database and table)
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE?_select=column (select statement by columns)
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE?_select=column[array id] (select statement by array colum)
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE?_select=* (select all from TABLE)
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE?_count=* (use count function)
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE?_count=column (use count function)
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE?_page=2&_page_size=10 (pagination, page_size 10 by default)
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE?FIELD=VALUE (filter)
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE?_renderer=xml (JSON by default)
Select operations over a VIEW
http://127.0.0.1:8000/DATABASE/SCHEMA/VIEW?_select=column (select statement by columns in VIEW)
http://127.0.0.1:8000/DATABASE/SCHEMA/VIEW?_select=* (select all from VIEW)
http://127.0.0.1:8000/DATABASE/SCHEMA/VIEW?_count=* (use count function)
http://127.0.0.1:8000/DATABASE/SCHEMA/VIEW?_count=column (use count function)
http://127.0.0.1:8000/DATABASE/SCHEMA/VIEW?_page=2&_page_size=10 (pagination, page_size 10 by default)
http://127.0.0.1:8000/DATABASE/SCHEMA/VIEW?FIELD=VALUE (filter)
http://127.0.0.1:8000/DATABASE/SCHEMA/VIEW?_renderer=xml (JSON by default)
Insert - POST
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE
JSON DATA:
{
"FIELD1": "string value",
"FIELD2": 1234567890
}
Update - PATCH/PUT
Using query string to make filter (WHERE), example:
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE?FIELD1=xyz
JSON DATA:
{
"FIELD1": "string value",
"FIELD2": 1234567890,
"ARRAYFIELD": ["value 1","value 2"]
}
Delete - DELETE
Using query string to make filter (WHERE), example:
http://127.0.0.1:8000/DATABASE/SCHEMA/TABLE?FIELD1=xyz
JOIN
Using query string to JOIN tables, example:
/DATABASE/SCHEMA/TABLE?_join=inner:users:friends.userid:$eq:users.id
Parameters:
- Join type
- Table
- Table field 1
- Operator (=, <, >, <=, >=)
- Table field 2
Query Operators
Name |
Description |
$eq |
Matches values that are equal to a specified value. |
$gt |
Matches values that are greater than a specified value. |
$gte |
Matches values that are greater than or equal to a specified value. |
$lt |
Matches values that are less than a specified value. |
$lte |
Matches values that are less than or equal to a specified value. |
$ne |
Matches all values that are not equal to a specified value. |
$in |
Matches any of the values specified in an array. |
$nin |
Matches none of the values specified in an array. |
ORDER BY
Using ORDER BY in queries you must pass in GET request the attribute _order
with fieldname(s) as value. For DESC order, use the prefix -
. For multiple orders, the fields are separated by comma.
Examples:
ASC
GET /DATABASE/SCHEMA/TABLE/?_order=fieldname
DESC
GET /DATABASE/SCHEMA/TABLE/?_order=-fieldname
Multiple Orders
GET /DATABASE/SCHEMA/TABLE/?_order=fieldname01,-fieldname02,fieldname03
Executing SQL scripts
If need perform an advanced SQL, you can write some scripts SQL and access them by REST. These scripts are templates where you can pass by URL, values to them.
awesome_folder/example_of_powerful.read.sql:
SELECT * FROM table WHERE name = "{{.field1}}" OR name = "{{.field2}}";
Get result:
GET /_QUERIES/awesome_folder/example_of_powerful?field1=foo&field2=bar
To activate it, you need configure a location to scripts in your prest.toml like:
[queries]
location = /path/to/queries/
Scripts templates rules
In your scripts, the fields to replace have to look like: field1 or field2 are examples
SELECT * FROM table WHERE name = "{{.field1}}" OR name = "{{.field2}}";
Script file must have a suffix based on http verb:
HTTP Verb |
Suffix |
GET |
.read.sql |
POST |
.write.sql |
PUT, PATCH |
.update.sql |
DELETE |
.delete.sql |
In queries.location
, you need given a folder to your scripts:
queries/
└── foo
└── some_get.read.sql
└── some_create.write.sql
└── some_update.update.sql
└── some_delete.delete.sql
└── bar
└── some_get.read.sql
└── some_create.write.sql
└── some_update.update.sql
└── some_delete.delete.sql
URL's to foo folder:
GET /_QUERIES/foo/some_get?field1=bar
POST /_QUERIES/foo/some_create?field1=bar
PUT /_QUERIES/foo/some_update?field1=bar
PATCH /_QUERIES/foo/some_update?field1=bar
DELETE /_QUERIES/foo/some_delete?field1=bar
URL's to bar folder:
GET /_QUERIES/bar/some_get?field1=foo
POST /_QUERIES/bar/some_create?field1=foo
PUT /_QUERIES/bar/some_update?field1=foo
PATCH /_QUERIES/bar/some_update?field1=foo
DELETE /_QUERIES/bar/some_delete?field1=foo
Template functions
- isSet return true if param is set
SELECT * FROM table
{{if isSet "field1"}}
WHERE name = "{{.field1}}"
{{end}}
;
- defaultOrValue return param value or default value
SELECT * FROM table WHERE name = '{{defaultOrValue "field1" "gopher"}}';
Permissions
Restrict mode
In the prest.toml you can configure read/write/delete permissions of each table.
[access]
restrict = true # can access only the tables listed below
restrict = false
: (default) the prest will serve in publish mode. You can write/read/delete everydata without configure permissions.
restruct = true
: you need configure the permissions of all tables.
Table permissions
Example:
[[access.tables]]
name = "test"
permissions = ["read", "write", "delete"]
fields = ["id", "name"]
attribute |
description |
table |
Table name |
permissions |
Table permissions. Options: read , write and delete |
fields |
Fields permitted for select |
Configuration example: prest.toml
CORS Support
In the prest.toml you can configurate the CORS allowed origin:
Example:
[cors]
alloworigin = ["http://postgres.rest", "http://foo.com"]