doc: add API documentation

doc/api.md

@@ -0,0 +1,104 @@
+API calls
+=========
+
+Host Management
+---------------
+
+```go
+type HostKind int
+
+const (
+  KindHTTP HostKind = iota
+  KindTCP
+  KindIRC
+  KindProxy
+)
+
+type Host struct {
+  ID            string `gorethink:"id,omitempty"`
+  Hostname      string `gorethink:"hostname"`
+  OnionHostname string `gorethink:"onionhostname"`
+  Token         string `gorethink:"token"`
+  OnionKey      []byte `gorethink:"onionKey" json:"-"` // PEM-encoded
+
+  Kind HostKind `gorethink:"hostKind"`
+  Port string `gorethink:"port"`
+
+  AllowedUsers []string `gorethink:"allowedUsers"`
+}
+```
+
+### AddHost
+
+This creates a new host in the routing mesh.
+
+```go
+type AddHostRequest struct {
+  BaseAPICall
+  Hostname string
+  OnionKey *rsa.PrivateKey
+}
+
+type AddHostResponse struct {
+  ID            string
+  Token         string // JWT
+  Hostname      string
+  OnionHostname string
+}
+```
+
+### GetHost
+
+### ModifyHost
+
+Token Management
+----------------
+
+```go
+type Token struct {
+  ID string `gorethink:"id,omitempty" json:"jti"`
+
+  ExpiresAt int64  `json:"exp,omitempty"`
+  IssuedAt  int64  `json:"iat,omitempty"`
+  Issuer    string `json:"iss,omitempty"`
+  Subject   string `json:"sub,omitempty"`
+
+  Revoked bool
+  RevocationID string
+  Scopes []string `json:"scopes"`
+}
+```
+
+### CreateInitialToken
+
+### ValidateToken
+
+### CreateToken
+
+### ListTokens
+
+### RevokeToken
+
+Metrics
+-------
+
+### Report
+
+Returns the following data for the last minute, the last 5 minutes and the last
+10 minutes:
+
+- Number of requests processed
+- Total request latency
+- Longest request latency
+- Shortest request latency
+
+Users
+-----
+
+```go
+type User struct {
+  ID string `gorethink:"id,omitempty"`
+  Email string `gorethink:"email"`
+  OauthMethod string `gorethink:"oauthMethod"`
+}
+```