feat(clients): add Go, Rust, C# and Dart clients for ResolveSpec and FunctionSpec

clients/resolvespec-go/client.go

@@ -0,0 +1,121 @@
+package resolvespec
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+)
+
+// APIError is the server error object.
+type APIError struct {
+	Code    string `json:"code"`
+	Message string `json:"message"`
+	Details any    `json:"details,omitempty"`
+	Detail  string `json:"detail,omitempty"` // server-side reason (funcspec / restheadspec)
+	SQL     string `json:"sql,omitempty"`
+}
+
+// Error is returned on a non-2xx response or an unsuccessful result.
+type Error struct {
+	StatusCode int
+	APIError
+}
+
+func (e *Error) Error() string {
+	if e.Message != "" {
+		return e.Message
+	}
+	return fmt.Sprintf("http %d", e.StatusCode)
+}
+
+type config struct {
+	baseURL string
+	token   string
+	headers http.Header
+	http    *http.Client
+}
+
+// Option configures a client.
+type Option func(*config)
+
+func WithToken(token string) Option        { return func(c *config) { c.token = token } }
+func WithHTTPClient(h *http.Client) Option { return func(c *config) { c.http = h } }
+func WithHeader(name, value string) Option {
+	return func(c *config) { c.headers.Set(name, value) }
+}
+
+func newConfig(baseURL string, opts []Option) config {
+	c := config{baseURL: strings.TrimRight(baseURL, "/"), headers: http.Header{}, http: &http.Client{Timeout: 30 * time.Second}}
+	for _, o := range opts {
+		o(&c)
+	}
+	return c
+}
+
+// headers: Content-Type < custom headers < bearer token.
+func (c *config) newRequest(ctx context.Context, method, u string, body []byte) (*http.Request, error) {
+	var r io.Reader
+	if body != nil {
+		r = bytes.NewReader(body)
+	}
+	req, err := http.NewRequestWithContext(ctx, method, u, r)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	for k, vs := range c.headers {
+		req.Header[k] = append([]string(nil), vs...)
+	}
+	if c.token != "" {
+		req.Header.Set("Authorization", "Bearer "+c.token)
+	}
+	return req, nil
+}
+
+func (c *config) do(req *http.Request) (*http.Response, []byte, error) {
+	resp, err := c.http.Do(req)
+	if err != nil {
+		return nil, nil, err
+	}
+	defer resp.Body.Close()
+	b, err := io.ReadAll(resp.Body)
+	return resp, b, err
+}
+
+func errorFrom(status int, body []byte) *Error {
+	e := &Error{StatusCode: status}
+	var env struct {
+		Error *APIError `json:"error"`
+	}
+	if json.Unmarshal(body, &env) == nil && env.Error != nil {
+		e.APIError = *env.Error
+	}
+	if e.Message == "" {
+		text := ""
+		if !json.Valid(body) {
+			text = strings.TrimSpace(string(body))
+			if len(text) > 200 {
+				text = text[:200]
+			}
+		}
+		if text == "" {
+			text = fmt.Sprintf("%s (%d)", http.StatusText(status), status)
+		}
+		e.Message = text
+	}
+	return e
+}
+
+func buildURL(base, schema, entity string, id string) string {
+	u := base + "/" + url.PathEscape(schema) + "/" + url.PathEscape(entity)
+	if id != "" {
+		u += "/" + url.PathEscape(id)
+	}
+	return u
+}