api: Add the Pinning Services API module

This fixes #1213. It adds partial support for the Pinning Services API with some caveats:

* RequestIDs == CIDs. This is a violation of the spec, as request IDs will not be unique etc.
* Pagination, name matching, metadata matching, ordering etc. are not supported in the List endpoint.
* The List endpoint only supports status filtering and cid query parameter.
* Created time property is not supported and always set to Now()

There is more work to do here: cleanup, extract useful types etc. and TESTS.

api/pinsvc/config.go

@@ -0,0 +1,128 @@
+package pinsvc
+
+import (
+	"net/http"
+	"time"
+
+	ma "github.com/multiformats/go-multiaddr"
+
+	"github.com/ipfs/ipfs-cluster/api/common"
+)
+
+const configKey = "restapi"
+const envConfigKey = "cluster_restapi"
+
+const minMaxHeaderBytes = 4096
+
+// Default values for Config.
+const (
+	DefaultReadTimeout       = 0
+	DefaultReadHeaderTimeout = 5 * time.Second
+	DefaultWriteTimeout      = 0
+	DefaultIdleTimeout       = 120 * time.Second
+	DefaultMaxHeaderBytes    = minMaxHeaderBytes
+)
+
+// Default values for Config.
+var (
+	// DefaultHTTPListenAddrs contains default listen addresses for the HTTP API.
+	DefaultHTTPListenAddrs = []string{"/ip4/127.0.0.1/tcp/9094"}
+	DefaultHeaders         = map[string][]string{}
+)
+
+// CORS defaults.
+var (
+	DefaultCORSAllowedOrigins = []string{"*"}
+	DefaultCORSAllowedMethods = []string{
+		http.MethodGet,
+	}
+	// rs/cors this will set sensible defaults when empty:
+	// {"Origin", "Accept", "Content-Type", "X-Requested-With"}
+	DefaultCORSAllowedHeaders = []string{}
+	DefaultCORSExposedHeaders = []string{
+		"Content-Type",
+		"X-Stream-Output",
+		"X-Chunked-Output",
+		"X-Content-Length",
+	}
+	DefaultCORSAllowCredentials = true
+	DefaultCORSMaxAge           time.Duration // 0. Means always.
+)
+
+// Config fully implements the config.ComponentConfig interface. Use
+// NewConfig() to instantiate. Config embeds a common.Config object.
+type Config struct {
+	common.Config
+}
+
+// NewConfig creates a Config object setting the necessary meta-fields in the
+// common.Config embedded object.
+func NewConfig() *Config {
+	cfg := Config{}
+	cfg.Config.ConfigKey = configKey
+	cfg.EnvConfigKey = envConfigKey
+	cfg.Logger = logger
+	cfg.RequestLogger = apiLogger
+	cfg.DefaultFunc = defaultFunc
+	cfg.APIErrorFunc = func(err error, status int) error {
+		return APIError{
+			Reason: err.Error(),
+		}
+	}
+	return &cfg
+}
+
+// ConfigKey returns a human-friendly identifier for this type of
+// Config.
+func (cfg *Config) ConfigKey() string {
+	return configKey
+}
+
+// Default initializes this Config with working values.
+func (cfg *Config) Default() error {
+	return defaultFunc(&cfg.Config)
+}
+
+// Sets all defaults for this config.
+func defaultFunc(cfg *common.Config) error {
+	// http
+	addrs := make([]ma.Multiaddr, 0, len(DefaultHTTPListenAddrs))
+	for _, def := range DefaultHTTPListenAddrs {
+		httpListen, err := ma.NewMultiaddr(def)
+		if err != nil {
+			return err
+		}
+		addrs = append(addrs, httpListen)
+	}
+	cfg.HTTPListenAddr = addrs
+	cfg.PathSSLCertFile = ""
+	cfg.PathSSLKeyFile = ""
+	cfg.ReadTimeout = DefaultReadTimeout
+	cfg.ReadHeaderTimeout = DefaultReadHeaderTimeout
+	cfg.WriteTimeout = DefaultWriteTimeout
+	cfg.IdleTimeout = DefaultIdleTimeout
+	cfg.MaxHeaderBytes = DefaultMaxHeaderBytes
+
+	// libp2p
+	cfg.ID = ""
+	cfg.PrivateKey = nil
+	cfg.Libp2pListenAddr = nil
+
+	// Auth
+	cfg.BasicAuthCredentials = nil
+
+	// Logs
+	cfg.HTTPLogFile = ""
+
+	// Headers
+	cfg.Headers = DefaultHeaders
+
+	cfg.CORSAllowedOrigins = DefaultCORSAllowedOrigins
+	cfg.CORSAllowedMethods = DefaultCORSAllowedMethods
+	cfg.CORSAllowedHeaders = DefaultCORSAllowedHeaders
+	cfg.CORSExposedHeaders = DefaultCORSExposedHeaders
+	cfg.CORSAllowCredentials = DefaultCORSAllowCredentials
+	cfg.CORSMaxAge = DefaultCORSMaxAge
+
+	return nil
+}