Building GraphQL queries with Python

+

=

The problem

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
        },
        pageInfo {
            startCursor
            endCursor
        }
    }
}

The problem

query {
    bookings (customerId: "81de7115-b0b2-49ad-ac03-3a56a488ebcd", orderBy: "startDate") {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
            cursor
        },
        pageInfo {
            startCursor
            endCursor
            hasNextPage
        }
    }
}

The problem

But with Python... 🤷‍♂️

query {
    bookings (customerId: "81de7115-b0b2-49ad-ac03-3a56a488ebcd", orderBy: "startDate") {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
            cursor
        },
        pageInfo {
            startCursor
            endCursor
            hasNextPage
        }
    }
}

The solution💡

https://github.com/profusion/sgqlc

Simple GraphQL Client

The solution💡

https://github.com/profusion/sgqlc

Simple GraphQL Client

(the one with most stars on GitHub ⭐)

(the most sophisticated one 🧙‍♂️)

sgqlc overview

sgqlc.types          - int, str, bool, etc.

sgqlc.types.datetime - date, time, datetime

```
sgqlc.types.relay    - Node, Connection
```

sgqlc.operation      - Query (the main entrypoint)

```
sgqlc.endpoint.http  - HTTP wrapper
```

sgqlc overview

```
sgqlc.types
```
```
sgqlc.types.datetime
```
```
sgqlc.types.relay
```
```
sgqlc.operation
```
```
sgqlc.endpoint.http
```

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
        },
        pageInfo {
            ...
        }
    }
}

Everything is a type, there are just various abstractions throughout the package.

sgqlc overview

```
sgqlc.types
```
```
sgqlc.types.datetime
```
```
sgqlc.types.relay
```
```
sgqlc.operation
```
```
sgqlc.endpoint.http
```

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
        },
        pageInfo {
            ...
        }
    }
}

sgqlc overview

```
sgqlc.types
```
```
sgqlc.types.datetime
```
```
sgqlc.types.relay
```
```
sgqlc.operation
```
```
sgqlc.endpoint.http
```

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
        },
        pageInfo {
            ...
        }
    }
}

Relay types are related to pagination, ordering & filtering.

Relay - edges & nodes

Query

edge

Booking

node

cursor

sgqlc overview

```
sgqlc.types
```
```
sgqlc.types.datetime
```
```
sgqlc.types.relay
```
```
sgqlc.operation
```
```
sgqlc.endpoint.http
```

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
        },
        pageInfo {
            ...
        }
    }
}

Relay types are related to pagination, ordering & filtering.

sgqlc overview

```
sgqlc.types
```
```
sgqlc.types.datetime
```
```
sgqlc.types.relay
```
```
sgqlc.operation
```
```
sgqlc.endpoint.http
```

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
        },
        pageInfo {
            ...
        }
    }
}

Operation == Query (data fetching)

sgqlc overview

```
sgqlc.types
```
```
sgqlc.types.datetime
```
```
sgqlc.types.relay
```
```
sgqlc.operation
```
```
sgqlc.endpoint.http
```

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
        },
        pageInfo {
            ...
        }
    }
}

Wraps the GraphQL query to a HTTP POST request with the query attached as a body.

Let's define our node

# schema.py

from sgqlc.types import String
from sgqlc.types.relay import Node
from sgqlc.types.datetime import DateTime


class BookingNode(Node):
    start_date = DateTime
    end_date = DateTime
    building_ref = String

Let's define our node

# schema.py

from sgqlc.types import String
from sgqlc.types.relay import Node
from sgqlc.types.datetime import DateTime


class BookingNode(Node):
    start_date = DateTime
    end_date = DateTime
    building_ref = String

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
            cursor
        },
        ...
    }
}

Let's define our node

# schema.py

from sgqlc.types import String
from sgqlc.types.relay import Node
from sgqlc.types.datetime import DateTime


class BookingNode(Node):
    start_date = DateTime
    end_date = DateTime
    building_ref = String

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
            cursor
        },
        ...
    }
}

The Node model appends the cursor to the node by default.

Let's define our edge

# schema.py

from sgqlc.types import String, Type, Field
from sgqlc.types.relay import Node
from sgqlc.types.datetime import DateTime


class BookingNode(Node):
    start_date = DateTime
    end_date = DateTime
    building_ref = String


class BookingEdge(Type):
    node = Field(BookingNode)

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
            cursor
        },
        ...
    }
}

Let's define our connection

# schema.py

from sgqlc.types import String, Type, Field
from sgqlc.types.relay import Node, Connection
from sgqlc.types.datetime import DateTime


class BookingNode(Node):
    start_date = DateTime
    end_date = DateTime
    building_ref = String


class BookingEdge(Type):
    node = Field(BookingNode)
    

class BookingConnection(Connection):
    edges = list_of(BookingEdge)

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
            cursor
        },
        ...
    }
}

Let's define our connection

# schema.py

from sgqlc.types import String, Type, Field
from sgqlc.types.relay import Node, Connection
from sgqlc.types.datetime import DateTime


class BookingNode(Node):
    start_date = DateTime
    end_date = DateTime
    building_ref = String


class BookingEdge(Type):
    node = Field(BookingNode)
    

class BookingConnection(Connection):
    edges = list_of(BookingEdge)

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
            cursor
        },
        pageInfo {
            startCursor
            endCursor
            hasNextPage
        }
    }
}

The Connection model appends the page info to the query by default.

Let's define our query

# schema.py

from sgqlc.types import String, Type, Field
from sgqlc.types.relay import Node, Connection
from sgqlc.types.datetime import DateTime


class BookingNode(Node):
    start_date = DateTime
    end_date = DateTime
    building_ref = String


class BookingEdge(Type):
    node = Field(BookingNode)
    

class BookingConnection(Connection):
    edges = list_of(BookingEdge)


class Query(Type):
    bookings = Field(
        BookingConnection
    )

query {
    bookings (...) {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
            cursor
        },
        pageInfo {
            startCursor
            endCursor
            hasNextPage
        }
    }
}

Let's add args to the query

from sgqlc.types import String, Type, Field
from sgqlc.types.relay import Node, Connection
from sgqlc.types.datetime import DateTime


class BookingNode(Node):
    start_date = DateTime
    end_date = DateTime
    building_ref = String


class BookingEdge(Type):
    node = Field(BookingNode)
    

class BookingConnection(Connection):
    edges = list_of(BookingEdge)


class Query(Type):
    bookings = Field(
        BookingConnection,
        args={
          'customer_id': String,
          'order_by': String
        }
    )

query {
    ... (customerId: "", orderBy: "") {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
            cursor
        },
        pageInfo {
            startCursor
            endCursor
            hasNextPage
        }
    }
}

The schema is done 🏗️

from sgqlc.types import String, Type, Field
from sgqlc.types.relay import Node, Connection
from sgqlc.types.datetime import DateTime


class BookingNode(Node):
    start_date = DateTime
    end_date = DateTime
    building_ref = String


class BookingEdge(Type):
    node = Field(BookingNode)
    

class BookingConnection(Connection):
    edges = list_of(BookingEdge)


class Query(Type):
    bookings = Field(
        BookingConnection,
        args={
          'customer_id': String,
          'order_by': String
        }
    )

query {
    ... (customerId: "", orderBy: "") {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
            cursor
        },
        pageInfo {
            startCursor
            endCursor
            hasNextPage
        }
    }
}

And last, but not least...

Let's build the query !👷

Initialize the query

from sgqlc.operation import Operation
from sgqlc.endpoint.http import HTTPEndpoint

from .schema import Query


bookings_query = Operation(Query)

Provide query filter params

from sgqlc.operation import Operation
from sgqlc.endpoint.http import HTTPEndpoint

from .schema import Query


bookings_query = Operation(Query)

bookings_query.bookings(customer_id='...', order_by='...')

Attach edges & nodes

from sgqlc.operation import Operation
from sgqlc.endpoint.http import HTTPEndpoint

from .schema import Query


bookings_query = Operation(Query)

bookings_query.bookings(customer_id='...', order_by='...')

bookings_query.bookings.edges()                 # Attaches all edges
bookings_query.bookings.edges.node.startDate()  # Attaches only a specific edge

Call a GraphQL endpoint

from sgqlc.operation import Operation
from sgqlc.endpoint.http import HTTPEndpoint

from .schema import Query


bookings_query = Operation(Query)

bookings_query.bookings(customer_id='...', order_by='...')

bookings_query.bookings.edges()                 # Attaches all edges
bookings_query.bookings.edges.node.startDate()  # Attaches only a specific edge

endpoint = HTTPEndpoint(url='https://...')
result = endpoint(query=bookings_query)         # __call__

from sgqlc.operation import Operation
from sgqlc.endpoint.http import HTTPEndpoint

from .schema import Query


bookings_query = Operation(Query)

bookings_query.bookings(customer_id='...', order_by='...')

bookings_query.bookings.edges()                 # Attaches all edges
bookings_query.bookings.edges.node.startDate()  # Attaches only a specific edge

endpoint = HTTPEndpoint(url='https://...')
result = endpoint(query=bookings_query)         # __call__

We got it!🦸‍♂️

But with Python! 🐍

query {
    bookings (customerId: "81de7115-b0b2-49ad-ac03-3a56a488ebcd", orderBy: "startDate") {
        edges {
            node {
                startDate
                endDate
                buildingRef
            }
            cursor
        },
        pageInfo {
            startCursor
            endCursor
            hasNextPage
        }
    }
}

Furthermore

```
first: <number>
```
```
limit: <number>
```
```
after: <cursor>
```
...

https://graphql.org/learn/pagination/

https://facebook.github.io/relay/graphql/connections.htm

https://relay.dev/docs/en/graphql-server-specification.html

Q&A 🙋

Building GraphQL queries with Python

By Ventsislav Tashev

Building GraphQL queries with Python

5 years ago
1,982

Ventsislav Tashev

v_tashev

Building GraphQL queries with Python

+

=

The problem

The problem

The problem

The problem

The problem

But with Python... 🤷‍♂️

The solution💡

The solution💡

The solution💡

sgqlc overview

sgqlc overview

sgqlc overview

sgqlc overview

Relay - edges & nodes

sgqlc overview

sgqlc overview

sgqlc overview

Let's define our node

Let's define our node

Let's define our node

Let's define our node

Let's define our edge

Let's define our connection

Let's define our connection

Let's define our query

Let's add args to the query

The schema is done 🏗️

And last, but not least...

And last, but not least...

Let's build the query !👷

Initialize the query

Provide query filter params

Attach edges & nodes

Call a GraphQL endpoint

We got it!🦸‍♂️

But with Python! 🐍

Furthermore

Q&A 🙋

Building GraphQL queries with Python

More from Ventsislav Tashev