1package provider
2
3// OpenAI Responses API client (api.openai.com/v1/responses).
4//
5// Strategy: reuse codexClient, which already speaks the Responses wire
6// format, via a header-rewriting RoundTripper. The public Responses API on
7// api.openai.com does not need ChatGPT subscription identity headers, so the
8// transport strips them if a shared request path supplied any.
9//
10// This is a separate provider from `openai` (which is Chat Completions);
11// users opt in by passing `--provider openai-responses` or by picking a
12// model whose catalog entry tags it under that provider id.
13//
14// Auth: API key via Authorization: Bearer (set by codexClient itself).
15// Different from openai-codex, which uses OAuth subscription tokens.
16
17import (
18 "net/http"
19 "net/url"
20 "strings"
21)
22
23const openaiResponsesDefaultBaseURL = "https://api.openai.com/v1/responses"
24
25// openaiResponsesTransport rewrites headers so the codex client (which
26// is designed for chatgpt.com OAuth tokens) can target the public
27// OpenAI Responses API with a normal API key.
28type openaiResponsesTransport struct {
29 inner http.RoundTripper
30}
31
32// openaiResponsesHTTPClient preserves the public Responses header boundary
33// when a caller injects a transport, for example to scope insecure TLS.
34func openaiResponsesHTTPClient(client *http.Client) *http.Client {
35 clone := *client
36 inner := clone.Transport
37 if inner == nil {
38 inner = http.DefaultTransport
39 }
40 clone.Transport = &openaiResponsesTransport{inner: inner}
41 return &clone
42}
43
44func (t *openaiResponsesTransport) RoundTrip(req *http.Request) (*http.Response, error) {
45 clone := req.Clone(req.Context())
46 // The codex client always sets chatgpt-account-id; api.openai.com
47 // doesn't need it and may reject the OAuth identity headers, so
48 // strip them.
49 clone.Header.Del("chatgpt-account-id")
50 clone.Header.Del("openai-beta")
51 clone.Header.Del("originator")
52 clone.Header.Del("user-agent")
53 // Keep Authorization: Bearer <key> as set by the codex client.
54 return t.inner.RoundTrip(clone)
55}
56
57// NewOpenAIResponses returns an OpenAI Responses-API client (API-key
58// flow). Uses the same wire format as the ChatGPT Codex backend but
59// with the public api.openai.com endpoint and standard Bearer auth.
60//
61// baseURL may be empty; defaults to https://api.openai.com/v1/responses.
62func NewOpenAIResponses(apiKey, baseURL string) Client {
63 return NewOpenAIResponsesNamed(apiKey, baseURL, "openai-responses")
64}
65
66// NewOpenAIResponsesNamed returns a public OpenAI Responses-API client
67// reporting the supplied provider name. This lets the `openai` provider
68// route Responses-only preview models without changing the visible provider.
69func NewOpenAIResponsesNamed(apiKey, baseURL, name string) Client {
70 baseURL = responsesURL(baseURL)
71 httpClient := openaiResponsesHTTPClient(&http.Client{Timeout: 0})
72 inner := &codexClient{
73 token: apiKey,
74 accountID: "", // unused; transport strips the header
75 baseURL: strings.TrimRight(baseURL, "/"),
76 errorLabel: "openai",
77 providerName: name,
78 capabilities: responsesCapabilities{
79 // Only the official OpenAI provider declares these extensions.
80 // A Responses-shaped custom endpoint must opt in through its
81 // own client rather than inheriting OpenAI's cache contract.
82 StablePromptCacheKey: officialOpenAIResponsesEndpoint(name, baseURL),
83 ExplicitPromptCacheBreakpoint: officialOpenAIResponsesEndpoint(name, baseURL),
84 },
85 http: httpClient,
86 }
87 var client Client = inner
88 if officialOpenAIResponsesEndpoint(name, baseURL) {
89 client = newResponsesWebSocketClient(inner)
90 }
91 return &renamedClient{inner: client, name: name}
92}
93
94func officialOpenAIResponsesEndpoint(name, endpoint string) bool {
95 if name != "openai" && name != "openai-responses" {
96 return false
97 }
98 u, err := url.Parse(endpoint)
99 return err == nil && u.Scheme == "https" && strings.EqualFold(u.Hostname(), "api.openai.com") && u.Path == "/v1/responses"
100}
101
102// responsesURL accepts either an API root or a complete Responses endpoint.
103// Catalog model entries generally carry API roots, while explicit overrides
104// may already include /responses.
105func responsesURL(baseURL string) string {
106 baseURL = strings.TrimRight(baseURL, "/")
107 if baseURL == "" {
108 return openaiResponsesDefaultBaseURL
109 }
110 if strings.HasSuffix(baseURL, "/responses") {
111 return baseURL
112 }
113 if versionSegmentSuffix.MatchString(baseURL) {
114 return baseURL + "/responses"
115 }
116 return baseURL + "/v1/responses"
117}