The OpenAI Go library provides convenient access to the OpenAI REST API from applications written in Go. The full API of this library can be found in api.md.
Warning
The latest version of this package uses a new design with significant breaking changes. Please refer to the migration guide for more information on how to update your code.
import ( "github.com/openai/openai-go" // imported as openai )Or to pin the version:
go get -u 'github.com/openai/openai-go@v0.1.0-beta.7'This library requires Go 1.18+.
The full API of this library can be found in api.md.
package main import ( "context" "fmt" "github.com/openai/openai-go" "github.com/openai/openai-go/option" "github.com/openai/openai-go/shared" ) func main() { client := openai.NewClient( option.WithAPIKey("My API Key"), // defaults to os.LookupEnv("OPENAI_API_KEY") ) chatCompletion, err := client.Chat.Completions.New(context.TODO(), openai.ChatCompletionNewParams{ Messages: []openai.ChatCompletionMessageParamUnion{ openai.UserMessage("Say this is a test"), }, Model: openai.ChatModelGPT4o, }) if err != nil { panic(err.Error()) } println(chatCompletion.Choices[0].Message.Content) }Conversations
param := openai.ChatCompletionNewParams{ Messages: []openai.ChatCompletionMessageParamUnion{ openai.UserMessage("What kind of houseplant is easy to take care of?"), }, Seed: openai.Int(1), Model: openai.ChatModelGPT4o, } completion, err := client.Chat.Completions.New(ctx, param) param.Messages = append(param.Messages, completion.Choices[0].Message.ToParam()) param.Messages = append(param.Messages, openai.UserMessage("How big are those?")) // continue the conversation completion, err = client.Chat.Completions.New(ctx, param)Streaming responses
question := "Write an epic" stream := client.Chat.Completions.NewStreaming(ctx, openai.ChatCompletionNewParams{ Messages: []openai.ChatCompletionMessageParamUnion{ openai.UserMessage(question), }, Seed: openai.Int(0), Model: openai.ChatModelGPT4o, }) // optionally, an accumulator helper can be used acc := openai.ChatCompletionAccumulator{} for stream.Next() { chunk := stream.Current() acc.AddChunk(chunk) if content, ok := acc.JustFinishedContent(); ok { println("Content stream finished:", content) } // if using tool calls if tool, ok := acc.JustFinishedToolCall(); ok { println("Tool call stream finished:", tool.Index, tool.Name, tool.Arguments) } if refusal, ok := acc.JustFinishedRefusal(); ok { println("Refusal stream finished:", refusal) } // it's best to use chunks after handling JustFinished events if len(chunk.Choices) > 0 { println(chunk.Choices[0].Delta.Content) } } if stream.Err() != nil { panic(stream.Err()) } // After the stream is finished, acc can be used like a ChatCompletion _ = acc.Choices[0].Message.ContentTool calling
import ( "encoding/json" // ... ) // ... question := "What is the weather in New York City?" params := openai.ChatCompletionNewParams{ Messages: []openai.ChatCompletionMessageParamUnion{ openai.UserMessage(question), }, Tools: []openai.ChatCompletionToolParam{ { Function: openai.FunctionDefinitionParam{ Name: "get_weather", Description: openai.String("Get weather at the given location"), Parameters: openai.FunctionParameters{ "type": "object", "properties": map[string]interface{}{ "location": map[string]string{ "type": "string", }, }, "required": []string{"location"}, }, }, }, }, Model: openai.ChatModelGPT4o, } // If there is a was a function call, continue the conversation params.Messages = append(params.Messages, completion.Choices[0].Message.ToParam()) for _, toolCall := range toolCalls { if toolCall.Function.Name == "get_weather" { // Extract the location from the function call arguments var args map[string]interface{} err := json.Unmarshal([]byte(toolCall.Function.Arguments), &args) if err != nil { panic(err) } location := args["location"].(string) // Simulate getting weather data weatherData := getWeather(location) // Print the weather data fmt.Printf("Weather in %s: %s\n", location, weatherData) params.Messages = append(params.Messages, openai.ToolMessage(weatherData, toolCall.ID)) } } // ... continue the conversation with the information provided by the toolSee the full tool calling example
Structured outputs
import ( "encoding/json" "github.com/invopop/jsonschema" // ... ) // A struct that will be converted to a Structured Outputs response schema type HistoricalComputer struct { Origin Origin `json:"origin" jsonschema_description:"The origin of the computer"` Name string `json:"full_name" jsonschema_description:"The name of the device model"` Legacy string `json:"legacy" jsonschema:"enum=positive,enum=neutral,enum=negative" jsonschema_description:"Its influence on the field of computing"` NotableFacts []string `json:"notable_facts" jsonschema_description:"A few key facts about the computer"` } type Origin struct { YearBuilt int64 `json:"year_of_construction" jsonschema_description:"The year it was made"` Organization string `json:"organization" jsonschema_description:"The organization that was in charge of its development"` } func GenerateSchema[T any]() interface{} { // Structured Outputs uses a subset of JSON schema // These flags are necessary to comply with the subset reflector := jsonschema.Reflector{ AllowAdditionalProperties: false, DoNotReference: true, } var v T schema := reflector.Reflect(v) return schema } // Generate the JSON schema at initialization time var HistoricalComputerResponseSchema = GenerateSchema[HistoricalComputer]() func main() { // ... question := "What computer ran the first neural network?" schemaParam := openai.ResponseFormatJSONSchemaJSONSchemaParam{ Name: "historical_computer", Description: openai.String("Notable information about a computer"), Schema: HistoricalComputerResponseSchema, Strict: openai.Bool(true), } chat, _ := client.Chat.Completions.New(ctx, openai.ChatCompletionNewParams{ // ... ResponseFormat: openai.ChatCompletionNewParamsResponseFormatUnion{ OfJSONSchema: &openai.ResponseFormatJSONSchemaParam{ JSONSchema: schemaParam, }, }, // only certain models can perform structured outputs Model: openai.ChatModelGPT4o2024_08_06, }) // extract into a well-typed struct var historicalComputer HistoricalComputer _ = json.Unmarshal([]byte(chat.Choices[0].Message.Content), &historicalComputer) historicalComputer.Name historicalComputer.Origin.YearBuilt historicalComputer.Origin.Organization for i, fact := range historicalComputer.NotableFacts { // ... } }See the full structured outputs example
The openai 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]. Use the provided constructors set param.Opt[T] fields such as openai.String(string), openai.Int(int64), etc.
Optional primitives, maps, slices and structs and string enums (represented as string) always feature the tag `json:"...,omitzero"`. Their zero values are considered omitted.
Any non-nil slice of length zero will serialize as an empty JSON array, "[]". Similarly, any non-nil map with length zero with serialize as an empty JSON object, "{}".
To send null instead of an param.Opt[T], use param.NullOpt[T](). To send null instead of a struct, use param.NullObj[T](), where T is a struct. To send a custom value instead of a struct, use param.OverrideObj[T](value).
To override request structs contain a .WithExtraFields(map[string]any) method which can be used to send non-conforming fields in the request body. Extra fields overwrite any struct fields with a matching key, so only use with trusted data.
params := openai.ExampleParams{ ID: "id_xxx", // required property Name: openai.String("..."), // optional property Description: param.NullOpt[string](), // explicit null property Point: openai.Point{ X: 0, // required field will serialize as 0 Y: openai.Int(1), // optional field will serialize as 1 // ... omitted non-required fields will not be serialized }, Origin: openai.Origin{}, // the zero value of [Origin] is considered omitted } // In cases where the API specifies a given type, // but you want to send something else, use [WithExtraFields]: params.WithExtraFields(map[string]any{ "x": 0.01, // send "x" as a float instead of int }) // Send a number instead of an object custom := param.OverrideObj[openai.FooParams](12)When available, use the .IsPresent() method to check if an optional parameter is not omitted or null. Otherwise, the param.IsOmitted(any) function can confirm the presence of any omitzero field.
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 }All fields in response structs are value types (not pointers or wrappers).
If a given field is null, not present, or invalid, the corresponding field will simply be its zero value. To handle optional fields, see the IsPresent() method below.
All response structs also include a special JSON field, containing more detailed information about each property, which you can use like so:
type Animal struct { Name string `json:"name,nullable"` Owners int `json:"owners"` Age int `json:"age"` JSON struct { Name resp.Field Owner resp.Field Age resp.Field } `json:"-"` } var res Animal json.Unmarshal([]byte(`{"name": null, "owners": 0}`), &res) // Use the IsPresent() method to handle optional fields res.Owners // 0 res.JSON.Owners.IsPresent() // true res.JSON.Owners.Raw() // "0" res.Age // 0 res.JSON.Age.IsPresent() // false res.JSON.Age.Raw() // "" // Use the IsExplicitNull() method to differentiate null and omitted res.Name // "" res.JSON.Name.IsPresent() // false res.JSON.Name.Raw() // "null" res.JSON.Name.IsExplicitNull() // trueThese .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()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 resp.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") }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 := openai.NewClient( // Adds a header to every request made by the client option.WithHeader("X-Some-Header", "custom_header_info"), ) client.Chat.Completions.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"}), )See the full list of request options.
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.FineTuning.Jobs.ListAutoPaging(context.TODO(), openai.FineTuningJobListParams{ Limit: openai.Int(20), }) // Automatically fetches more pages as needed. for iter.Next() { fineTuningJob := iter.Current() fmt.Printf("%+v\n", fineTuningJob) } 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.FineTuning.Jobs.List(context.TODO(), openai.FineTuningJobListParams{ Limit: openai.Int(20), }) for page != nil { for _, job := range page.Data { fmt.Printf("%+v\n", job) } page, err = page.GetNextPage() } if err != nil { panic(err.Error()) }When the API returns a non-success status code, we return an error with type *openai.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.FineTuning.Jobs.New(context.TODO(), openai.FineTuningJobNewParams{ Model: openai.FineTuningJobNewParamsModelBabbage002, TrainingFile: "file-abc123", }) if err != nil { var apierr *openai.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 "/fine_tuning/jobs": 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.
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.Chat.Completions.New( ctx, openai.ChatCompletionNewParams{ Messages: []openai.ChatCompletionMessageParamUnion{{ OfUser: &openai.ChatCompletionUserMessageParam{ Content: openai.ChatCompletionUserMessageParamContentUnion{ OfString: openai.String("How can I list all files in a directory using Python?"), }, }, }}, Model: shared.ChatModelO3Mini, }, // This sets the per-retry timeout option.WithRequestTimeout(20*time.Second), )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 openai.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.
// A file from the file system file, err := os.Open("input.jsonl") openai.FileNewParams{ File: file, Purpose: openai.FilePurposeFineTune, } // A file from a string openai.FileNewParams{ File: strings.NewReader("my file contents"), Purpose: openai.FilePurposeFineTune, } // With a custom filename and contentType openai.FileNewParams{ File: openai.File(strings.NewReader(`{"hello": "foo"}`), "file.go", "application/json"), Purpose: openai.FilePurposeFineTune, }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 := openai.NewClient( option.WithMaxRetries(0), // default is 2 ) // Override per-request: client.Chat.Completions.New( context.TODO(), openai.ChatCompletionNewParams{ Messages: []openai.ChatCompletionMessageParamUnion{{ OfUser: &openai.ChatCompletionUserMessageParam{ Content: openai.ChatCompletionUserMessageParamContentUnion{ OfString: openai.String("How can I get the name of the current day in JavaScript?"), }, }, }}, Model: shared.ChatModelO3Mini, }, option.WithMaxRetries(5), )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 chatCompletion, err := client.Chat.Completions.New( context.TODO(), openai.ChatCompletionNewParams{ Messages: []openai.ChatCompletionMessageParamUnion{{ OfUser: &openai.ChatCompletionUserMessageParam{ Content: openai.ChatCompletionUserMessageParamContentUnion{ OfString: openai.String("Say this is a test"), }, }, }}, Model: shared.ChatModelO3Mini, }, option.WithResponseInto(&response), ) if err != nil { // handle error } fmt.Printf("%+v\n", chatCompletion) fmt.Printf("Status Code: %d\n", response.StatusCode) fmt.Printf("Headers: %+#v\n", response.Header)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.
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]interface{} // 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 { … }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: openai.String("John"), }, } client.Foo.New(context.Background(), params, option.WithJSONSet("data.last_name", "Doe"))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.
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 := openai.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.
To use this library with [Azure OpenAI]https://learn.microsoft.com/azure/ai-services/openai/overview), use the option.RequestOption functions in the azure package.
package main import ( "github.com/Azure/azure-sdk-for-go/sdk/azidentity" "github.com/openai/openai-go" "github.com/openai/openai-go/azure" ) func main() { const azureOpenAIEndpoint = "https://<azure-openai-resource>.openai.azure.com" // The latest API versions, including previews, can be found here: // ttps://learn.microsoft.com/en-us/azure/ai-services/openai/reference#rest-api-versionng const azureOpenAIAPIVersion = "2024-06-01" tokenCredential, err := azidentity.NewDefaultAzureCredential(nil) if err != nil { fmt.Printf("Failed to create the DefaultAzureCredential: %s", err) os.Exit(1) } client := openai.NewClient( azure.WithEndpoint(azureOpenAIEndpoint, azureOpenAIAPIVersion), // Choose between authenticating using a TokenCredential or an API Key azure.WithTokenCredential(tokenCredential), // or azure.WithAPIKey(azureOpenAIAPIKey), ) }This package generally follows SemVer conventions, though certain backwards-incompatible changes may be released as minor versions:
- 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.)
- 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.