gcore

README

Gcore Go API Library

The Gcore Go library provides convenient access to the Gcore REST API from applications written in Go.

It is generated with Stainless.

Installation

import (
	"github.com/G-Core/gcore-go" // imported as gcore
)

Or to pin the version:

go get -u 'github.com/G-Core/gcore-go@v0.12.0'

Requirements

This library requires Go 1.18+.

Usage

The full API of this library can be found in api.md.

package main

import (
	"context"
	"fmt"

	"github.com/G-Core/gcore-go"
	"github.com/G-Core/gcore-go/cloud"
	"github.com/G-Core/gcore-go/option"
)

func main() {
	client := gcore.NewClient(
		option.WithAPIKey("My API Key"), // defaults to os.LookupEnv("GCORE_API_KEY")
	)
	project, err := client.Cloud.Projects.New(context.TODO(), cloud.ProjectNewParams{
		Name: "New Project",
	})
	if err != nil {
		panic(err.Error())
	}
	fmt.Printf("%+v\n", project.ID)
}

Request fields

The gcore library uses the omitzero semantics from the Go 1.24+ encoding/json release for request fields.

Required primitive fields (int64, string, etc.) feature the tag `json:"...,required"`. These fields are always serialized, even their zero values.

Optional primitive types are wrapped in a param.Opt[T]. These fields can be set with the provided constructors, gcore.String(string), gcore.Int(int64), etc.

Any param.Opt[T], map, slice, struct or string enum uses the tag `json:"...,omitzero"`. Its zero value is considered omitted.

The param.IsOmitted(any) function can confirm the presence of any omitzero field.

p := gcore.ExampleParams{
	ID:   "id_xxx",            // required property
	Name: gcore.String("..."), // optional property

	Point: gcore.Point{
		X: 0,            // required field will serialize as 0
		Y: gcore.Int(1), // optional field will serialize as 1
		// ... omitted non-required fields will not be serialized
	},

	Origin: gcore.Origin{}, // the zero value of [Origin] is considered omitted
}

To send null instead of a param.Opt[T], use param.Null[T](). To send null instead of a struct T, use param.NullStruct[T]().

p.Name = param.Null[string]()       // 'null' instead of string
p.Point = param.NullStruct[Point]() // 'null' instead of struct

param.IsNull(p.Name)  // true
param.IsNull(p.Point) // true

Request structs contain a .SetExtraFields(map[string]any) method which can send non-conforming fields in the request body. Extra fields overwrite any struct fields with a matching key. For security reasons, only use SetExtraFields with trusted data.

To send a custom value instead of a struct, use param.Override[T](value).

// In cases where the API specifies a given type,
// but you want to send something else, use [SetExtraFields]:
p.SetExtraFields(map[string]any{
	"x": 0.01, // send "x" as a float instead of int
})

// Send a number instead of an object
custom := param.Override[gcore.FooParams](12)

Request unions

Unions are represented as a struct with fields prefixed by "Of" for each of it's variants, only one field can be non-zero. The non-zero field will be serialized.

Sub-properties of the union can be accessed via methods on the union struct. These methods return a mutable pointer to the underlying data, if present.

// Only one field can be non-zero, use param.IsOmitted() to check if a field is set
type AnimalUnionParam struct {
	OfCat *Cat `json:",omitzero,inline`
	OfDog *Dog `json:",omitzero,inline`
}

animal := AnimalUnionParam{
	OfCat: &Cat{
		Name: "Whiskers",
		Owner: PersonParam{
			Address: AddressParam{Street: "3333 Coyote Hill Rd", Zip: 0},
		},
	},
}

// Mutating a field
if address := animal.GetOwner().GetAddress(); address != nil {
	address.ZipCode = 94304
}

Response objects

All fields in response structs are ordinary value types (not pointers or wrappers). Response structs also include a special JSON field containing metadata about each property.

type Animal struct {
	Name   string `json:"name,nullable"`
	Owners int    `json:"owners"`
	Age    int    `json:"age"`
	JSON   struct {
		Name        respjson.Field
		Owner       respjson.Field
		Age         respjson.Field
		ExtraFields map[string]respjson.Field
	} `json:"-"`
}

To handle optional data, use the .Valid() method on the JSON field. .Valid() returns true if a field is not null, not present, or couldn't be marshaled.

If .Valid() is false, the corresponding field will simply be its zero value.

raw := `{"owners": 1, "name": null}`

var res Animal
json.Unmarshal([]byte(raw), &res)

// Accessing regular fields

res.Owners // 1
res.Name   // ""
res.Age    // 0

// Optional field checks

res.JSON.Owners.Valid() // true
res.JSON.Name.Valid()   // false
res.JSON.Age.Valid()    // false

// Raw JSON values

res.JSON.Owners.Raw()                  // "1"
res.JSON.Name.Raw() == "null"          // true
res.JSON.Name.Raw() == respjson.Null   // true
res.JSON.Age.Raw() == ""               // true
res.JSON.Age.Raw() == respjson.Omitted // true

These .JSON structs also include an ExtraFields map containing any properties in the json response that were not specified in the struct. This can be useful for API features not yet present in the SDK.

body := res.JSON.ExtraFields["my_unexpected_field"].Raw()

Response Unions

In responses, unions are represented by a flattened struct containing all possible fields from each of the object variants. To convert it to a variant use the .AsFooVariant() method or the .AsAny() method if present.

If a response value union contains primitive values, primitive fields will be alongside the properties but prefixed with Of and feature the tag json:"...,inline".

type AnimalUnion struct {
	// From variants [Dog], [Cat]
	Owner Person `json:"owner"`
	// From variant [Dog]
	DogBreed string `json:"dog_breed"`
	// From variant [Cat]
	CatBreed string `json:"cat_breed"`
	// ...

	JSON struct {
		Owner respjson.Field
		// ...
	} `json:"-"`
}

// If animal variant
if animal.Owner.Address.ZipCode == "" {
	panic("missing zip code")
}

// Switch on the variant
switch variant := animal.AsAny().(type) {
case Dog:
case Cat:
default:
	panic("unexpected type")
}

RequestOptions

This library uses the functional options pattern. Functions defined in the option package return a RequestOption, which is a closure that mutates a RequestConfig. These options can be supplied to the client or at individual requests. For example:

client := gcore.NewClient(
	// Adds a header to every request made by the client
	option.WithHeader("X-Some-Header", "custom_header_info"),
)

client.Cloud.Projects.New(context.TODO(), ...,
	// Override the header
	option.WithHeader("X-Some-Header", "some_other_custom_header_info"),
	// Add an undocumented field to the request body, using sjson syntax
	option.WithJSONSet("some.json.path", map[string]string{"my": "object"}),
)

The request option option.WithDebugLog(nil) may be helpful while debugging.

See the full list of request options.

Pagination

This library provides some conveniences for working with paginated list endpoints.

You can use .ListAutoPaging() methods to iterate through items across all pages:

iter := client.Cloud.Projects.ListAutoPaging(context.TODO(), cloud.ProjectListParams{
	Limit: gcore.Int(10),
})
// Automatically fetches more pages as needed.
for iter.Next() {
	project := iter.Current()
	fmt.Printf("%+v\n", project)
}
if err := iter.Err(); err != nil {
	panic(err.Error())
}

Or you can use simple .List() methods to fetch a single page and receive a standard response object with additional helper methods like .GetNextPage(), e.g.:

page, err := client.Cloud.Projects.List(context.TODO(), cloud.ProjectListParams{
	Limit: gcore.Int(10),
})
for page != nil {
	for _, project := range page.Results {
		fmt.Printf("%+v\n", project)
	}
	page, err = page.GetNextPage()
}
if err != nil {
	panic(err.Error())
}

Errors

When the API returns a non-success status code, we return an error with type *gcore.Error. This contains the StatusCode, *http.Request, and *http.Response values of the request, as well as the JSON of the error body (much like other response objects in the SDK).

To handle errors, we recommend that you use the errors.As pattern:

_, err := client.Cloud.Projects.New(context.TODO(), cloud.ProjectNewParams{
	Name: "New Project",
})
if err != nil {
	var apierr *gcore.Error
	if errors.As(err, &apierr) {
		println(string(apierr.DumpRequest(true)))  // Prints the serialized HTTP request
		println(string(apierr.DumpResponse(true))) // Prints the serialized HTTP response
	}
	panic(err.Error()) // GET "/cloud/v1/projects": 400 Bad Request { ... }
}

When other errors occur, they are returned unwrapped; for example, if HTTP transport fails, you might receive *url.Error wrapping *net.OpError.

Timeouts

Requests do not time out by default; use context to configure a timeout for a request lifecycle.

Note that if a request is retried, the context timeout does not start over. To set a per-retry timeout, use option.WithRequestTimeout().

// This sets the timeout for the request, including all the retries.
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Minute)
defer cancel()
client.Cloud.Projects.New(
	ctx,
	cloud.ProjectNewParams{
		Name: "New Project",
	},
	// This sets the per-retry timeout
	option.WithRequestTimeout(20*time.Second),
)

File uploads

Request parameters that correspond to file uploads in multipart requests are typed as io.Reader. The contents of the io.Reader will by default be sent as a multipart form part with the file name of "anonymous_file" and content-type of "application/octet-stream".

The file name and content-type can be customized by implementing Name() string or ContentType() string on the run-time type of io.Reader. Note that os.File implements Name() string, so a file returned by os.Open will be sent with the file name on disk.

We also provide a helper gcore.File(reader io.Reader, filename string, contentType string) which can be used to wrap any io.Reader with the appropriate file name and content type.

Retries

Certain errors will be automatically retried 2 times by default, with a short exponential backoff. We retry by default all connection errors, 408 Request Timeout, 409 Conflict, 429 Rate Limit, and >=500 Internal errors.

You can use the WithMaxRetries option to configure or disable this:

// Configure the default for all requests:
client := gcore.NewClient(
	option.WithMaxRetries(0), // default is 2
)

// Override per-request:
client.Cloud.Projects.New(
	context.TODO(),
	cloud.ProjectNewParams{
		Name: "New Project",
	},
	option.WithMaxRetries(5),
)

Accessing raw response data (e.g. response headers)

You can access the raw HTTP response data by using the option.WithResponseInto() request option. This is useful when you need to examine response headers, status codes, or other details.

// Create a variable to store the HTTP response
var response *http.Response
project, err := client.Cloud.Projects.New(
	context.TODO(),
	cloud.ProjectNewParams{
		Name: "New Project",
	},
	option.WithResponseInto(&response),
)
if err != nil {
	// handle error
}
fmt.Printf("%+v\n", project)

fmt.Printf("Status Code: %d\n", response.StatusCode)
fmt.Printf("Headers: %+#v\n", response.Header)

Making custom/undocumented requests

This library is typed for convenient access to the documented API. If you need to access undocumented endpoints, params, or response properties, the library can still be used.

Undocumented endpoints

To make requests to undocumented endpoints, you can use client.Get, client.Post, and other HTTP verbs. RequestOptions on the client, such as retries, will be respected when making these requests.

var (
    // params can be an io.Reader, a []byte, an encoding/json serializable object,
    // or a "…Params" struct defined in this library.
    params map[string]any

    // result can be an []byte, *http.Response, a encoding/json deserializable object,
    // or a model defined in this library.
    result *http.Response
)
err := client.Post(context.Background(), "/unspecified", params, &result)
if err != nil {
    …
}

Undocumented request params

To make requests using undocumented parameters, you may use either the option.WithQuerySet() or the option.WithJSONSet() methods.

params := FooNewParams{
    ID:   "id_xxxx",
    Data: FooNewParamsData{
        FirstName: gcore.String("John"),
    },
}
client.Foo.New(context.Background(), params, option.WithJSONSet("data.last_name", "Doe"))

Undocumented response properties

To access undocumented response properties, you may either access the raw JSON of the response as a string with result.JSON.RawJSON(), or get the raw JSON of a particular field on the result with result.JSON.Foo.Raw().

Any fields that are not present on the response struct will be saved and can be accessed by result.JSON.ExtraFields() which returns the extra fields as a map[string]Field.

Middleware

We provide option.WithMiddleware which applies the given middleware to requests.

func Logger(req *http.Request, next option.MiddlewareNext) (res *http.Response, err error) {
	// Before the request
	start := time.Now()
	LogReq(req)

	// Forward the request to the next handler
	res, err = next(req)

	// Handle stuff after the request
	end := time.Now()
	LogRes(res, err, start - end)

    return res, err
}

client := gcore.NewClient(
	option.WithMiddleware(Logger),
)

When multiple middlewares are provided as variadic arguments, the middlewares are applied left to right. If option.WithMiddleware is given multiple times, for example first in the client then the method, the middleware in the client will run first and the middleware given in the method will run next.

You may also replace the default http.Client with option.WithHTTPClient(client). Only one http client is accepted (this overwrites any previous client) and receives requests after any middleware has been applied.

Semantic versioning

This package generally follows SemVer conventions, though certain backwards-incompatible changes may be released as minor versions:

1. Changes to library internals which are technically public but not intended or documented for external use. (Please open a GitHub issue to let us know if you are relying on such internals.)
2. Changes that we do not expect to impact the vast majority of users in practice.

We take backwards-compatibility seriously and work hard to ensure you can rely on a smooth upgrade experience.

We are keen for your feedback; please open an issue with questions, bugs, or suggestions.

Contributing

See the contributing documentation.

License

Documentation

Index

• func Bool(b bool) param.Opt[bool]
• func BoolPtr(v bool) *bool
• func DefaultClientOptions() []option.RequestOption
• func File(rdr io.Reader, filename string, contentType string) file
• func Float(f float64) param.Opt[float64]
• func FloatPtr(v float64) *float64
• func Int(i int64) param.Opt[int64]
• func IntPtr(v int64) *int64
• func Opt[T comparable](v T) param.Opt[T]
• func Ptr[T any](v T) *T
• func String(s string) param.Opt[string]
• func StringPtr(v string) *string
• func Time(t time.Time) param.Opt[time.Time]
• func TimePtr(v time.Time) *time.Time
• type Client
  • func NewClient(opts ...option.RequestOption) (r Client)
  • func (r *Client) Delete(ctx context.Context, path string, params any, res any, ...) error
  • func (r *Client) Execute(ctx context.Context, method string, path string, params any, res any, ...) error
  • func (r *Client) Get(ctx context.Context, path string, params any, res any, ...) error
  • func (r *Client) Patch(ctx context.Context, path string, params any, res any, ...) error
  • func (r *Client) Post(ctx context.Context, path string, params any, res any, ...) error
  • func (r *Client) Put(ctx context.Context, path string, params any, res any, ...) error
• type Error

Functions

func Bool

func Bool(b bool) param.Opt[bool]

func BoolPtr

func BoolPtr(v bool) *bool

func DefaultClientOptions

func DefaultClientOptions() []option.RequestOption

DefaultClientOptions read from the environment (GCORE_API_KEY, GCORE_CLOUD_PROJECT_ID, GCORE_CLOUD_REGION_ID, GCORE_BASE_URL). This should be used to initialize new clients.

func File

func File(rdr io.Reader, filename string, contentType string) file

func Float

func Float(f float64) param.Opt[float64]

func FloatPtr

func FloatPtr(v float64) *float64

func Int

func Int(i int64) param.Opt[int64]

func IntPtr

func IntPtr(v int64) *int64

func Opt

func Opt[T comparable](v T) param.Opt[T]

func Ptr

func Ptr[T any](v T) *T

func String

func String(s string) param.Opt[string]

func StringPtr

func StringPtr(v string) *string

func Time

func Time(t time.Time) param.Opt[time.Time]

func TimePtr

func TimePtr(v time.Time) *time.Time

Types

type Client

type Client struct {
	Options   []option.RequestOption
	Cloud     cloud.CloudService
	Waap      waap.WaapService
	Iam       iam.IamService
	Fastedge  fastedge.FastedgeService
	Streaming streaming.StreamingService
	Security  security.SecurityService
	DNS       dns.DNSService
	Storage   storage.StorageService
}

Client creates a struct with services and top level methods that help with interacting with the gcore API. You should not instantiate this client directly, and instead use the NewClient method instead.

func NewClient

func NewClient(opts ...option.RequestOption) (r Client)

NewClient generates a new client with the default option read from the environment (GCORE_API_KEY, GCORE_CLOUD_PROJECT_ID, GCORE_CLOUD_REGION_ID, GCORE_BASE_URL). The option passed in as arguments are applied after these default arguments, and all option will be passed down to the services and requests that this client makes.

func (*Client) Delete

func (r *Client) Delete(ctx context.Context, path string, params any, res any, opts ...option.RequestOption) error

Delete makes a DELETE request with the given URL, params, and optionally deserializes to a response. See [Execute] documentation on the params and response.

func (*Client) Execute

func (r *Client) Execute(ctx context.Context, method string, path string, params any, res any, opts ...option.RequestOption) error

Execute makes a request with the given context, method, URL, request params, response, and request options. This is useful for hitting undocumented endpoints while retaining the base URL, auth, retries, and other options from the client.

If a byte slice or an io.Reader is supplied to params, it will be used as-is for the request body.

The params is by default serialized into the body using encoding/json. If your type implements a MarshalJSON function, it will be used instead to serialize the request. If a URLQuery method is implemented, the returned [url.Values] will be used as query strings to the url.

If your params struct uses param.Field, you must provide either [MarshalJSON], [URLQuery], and/or [MarshalForm] functions. It is undefined behavior to use a struct uses param.Field without specifying how it is serialized.

Any "…Params" object defined in this library can be used as the request argument. Note that 'path' arguments will not be forwarded into the url.

The response body will be deserialized into the res variable, depending on its type:

• A pointer to a *http.Response is populated by the raw response.
• A pointer to a byte array will be populated with the contents of the request body.
• A pointer to any other type uses this library's default JSON decoding, which respects UnmarshalJSON if it is defined on the type.
• A nil value will not read the response body.

For even greater flexibility, see option.WithResponseInto and option.WithResponseBodyInto.

func (*Client) Get

func (r *Client) Get(ctx context.Context, path string, params any, res any, opts ...option.RequestOption) error

Get makes a GET request with the given URL, params, and optionally deserializes to a response. See [Execute] documentation on the params and response.

func (*Client) Patch

func (r *Client) Patch(ctx context.Context, path string, params any, res any, opts ...option.RequestOption) error

Patch makes a PATCH request with the given URL, params, and optionally deserializes to a response. See [Execute] documentation on the params and response.

func (*Client) Post

func (r *Client) Post(ctx context.Context, path string, params any, res any, opts ...option.RequestOption) error

Post makes a POST request with the given URL, params, and optionally deserializes to a response. See [Execute] documentation on the params and response.

func (*Client) Put

func (r *Client) Put(ctx context.Context, path string, params any, res any, opts ...option.RequestOption) error

Put makes a PUT request with the given URL, params, and optionally deserializes to a response. See [Execute] documentation on the params and response.

type Error

type Error = apierror.Error