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 while retaining
9// the intentional OpenCode Go client identity.
10//
11// This is a separate provider from `openai` (which is Chat Completions);
12// users opt in by passing `--provider openai-responses` or by picking a
13// model whose catalog entry tags it under that provider id.
14//
15// Auth: API key via Authorization: Bearer (set by codexClient itself).
16// Different from openai-codex, which uses OAuth subscription tokens.
17
18import (
19 "net/http"
20 "net/url"
21 "strings"
22)
23
24const openaiResponsesDefaultBaseURL = "https://api.openai.com/v1/responses"
25
26// openaiResponsesTransport rewrites headers so the codex client (which
27// is designed for chatgpt.com OAuth tokens) can target the public
28// OpenAI Responses API with a normal API key.
29type openaiResponsesTransport struct {
30 inner http.RoundTripper
31}
32
33// openaiResponsesHTTPClient preserves the public Responses header boundary
34// when a caller injects a transport, for example to scope insecure TLS.
35func openaiResponsesHTTPClient(client *http.Client) *http.Client {
36 clone := *client
37 inner := clone.Transport
38 if inner == nil {
39 inner = http.DefaultTransport
40 }
41 clone.Transport = &openaiResponsesTransport{inner: inner}
42 return &clone
43}
44
45func (t *openaiResponsesTransport) RoundTrip(req *http.Request) (*http.Response, error) {
46 clone := req.Clone(req.Context())
47 // The codex client always sets chatgpt-account-id; api.openai.com
48 // doesn't need it and may reject the OAuth identity headers, so
49 // strip them.
50 clone.Header.Del("chatgpt-account-id")
51 clone.Header.Del("openai-beta")
52 clone.Header.Del("originator")
53 if clone.Header.Get("x-opencode-client") != openCodeGoClient {
54 clone.Header.Del("user-agent")
55 }
56 // The shared Responses client sets a Bearer header even with an empty key.
57 // Keyless custom Responses endpoints need no Authorization header at all.
58 if strings.TrimSpace(clone.Header.Get("authorization")) == "Bearer" {
59 clone.Header.Del("authorization")
60 }
61 return t.inner.RoundTrip(clone)
62}
63
64// NewOpenAIResponses returns an OpenAI Responses-API client (API-key
65// flow). Uses the same wire format as the ChatGPT Codex backend but
66// with the public api.openai.com endpoint and standard Bearer auth.
67//
68// baseURL may be empty; defaults to https://api.openai.com/v1/responses.
69func NewOpenAIResponses(apiKey, baseURL string) Client {
70 return NewOpenAIResponsesNamed(apiKey, baseURL, "openai-responses")
71}
72
73// NewOpenAIResponsesNamed returns a public OpenAI Responses-API client
74// reporting the supplied provider name. This lets the `openai` provider
75// route Responses-only preview models without changing the visible provider.
76func NewOpenAIResponsesNamed(apiKey, baseURL, name string) Client {
77 baseURL = responsesURL(baseURL)
78 httpClient := openaiResponsesHTTPClient(&http.Client{Timeout: 0})
79 inner := &codexClient{
80 token: apiKey,
81 accountID: "", // unused; transport strips the header
82 baseURL: strings.TrimRight(baseURL, "/"),
83 errorLabel: "openai",
84 providerName: name,
85 capabilities: responsesCapabilities{
86 // Only the official OpenAI provider declares these extensions.
87 // A Responses-shaped custom endpoint must opt in through its
88 // own client rather than inheriting OpenAI's cache contract.
89 StablePromptCacheKey: officialOpenAIResponsesEndpoint(name, baseURL),
90 ExplicitPromptCacheBreakpoint: officialOpenAIResponsesEndpoint(name, baseURL),
91 },
92 http: httpClient,
93 }
94 var client Client = inner
95 if officialOpenAIResponsesEndpoint(name, baseURL) {
96 client = newResponsesWebSocketClient(inner)
97 }
98 return &renamedClient{inner: client, name: name}
99}
100
101func officialOpenAIResponsesEndpoint(name, endpoint string) bool {
102 if name != "openai" && name != "openai-responses" {
103 return false
104 }
105 u, err := url.Parse(endpoint)
106 return err == nil && u.Scheme == "https" && strings.EqualFold(u.Hostname(), "api.openai.com") && u.Path == "/v1/responses"
107}
108
109// responsesURL accepts either an API root or a complete Responses endpoint.
110// Catalog model entries generally carry API roots, while explicit overrides
111// may already include /responses.
112func responsesURL(baseURL string) string {
113 baseURL = strings.TrimRight(baseURL, "/")
114 if baseURL == "" {
115 return openaiResponsesDefaultBaseURL
116 }
117 if strings.HasSuffix(baseURL, "/responses") {
118 return baseURL
119 }
120 if versionSegmentSuffix.MatchString(baseURL) {
121 return baseURL + "/responses"
122 }
123 return baseURL + "/v1/responses"
124}