feat: initial version

client.go

@@ -0,0 +1,122 @@
+package client
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+)
+
+// CompanyPrivileges contains the privileges for a combination of email address and company id
+type CompanyPrivileges struct {
+	Admin      bool `json:"admin"`
+	Company    bool `json:"company"`
+	Consumer   bool `json:"consumer"`
+	Time       bool `json:"time"`
+	Invoicing  bool `json:"invoicing"`
+	Accounting bool `json:"accounting"`
+	Supplier   bool `json:"supplier"`
+}
+
+// PrivilegeAdded is the event sent when a new privilege is added
+type PrivilegeAdded struct {
+	Email      string `json:"email"`
+	CompanyID  string `json:"companyId"`
+	Admin      bool   `json:"admin"`
+	Company    bool   `json:"company"`
+	Consumer   bool   `json:"consumer"`
+	Time       bool   `json:"time"`
+	Invoicing  bool   `json:"invoicing"`
+	Accounting bool   `json:"accounting"`
+	Supplier   bool   `json:"supplier"`
+}
+
+// PrivilegeHandler processes PrivilegeAdded-events and fetches the initial set of privileges from an authz-service
+type PrivilegeHandler struct {
+	client     *http.Client
+	baseURL    string
+	privileges map[string]map[string]CompanyPrivileges
+}
+
+// OptsFunc is used to configure the PrivilegeHandler
+type OptsFunc func(handler *PrivilegeHandler)
+
+// WithBaseURL sets the base URL to the authz-service
+func WithBaseURL(url string) OptsFunc {
+	return func(handler *PrivilegeHandler) {
+		handler.baseURL = url
+	}
+}
+
+// New creates a new PrivilegeHandler. Pass OptsFuncs to configure.
+func New(opts ...OptsFunc) *PrivilegeHandler {
+	handler := &PrivilegeHandler{
+		client:     &http.Client{},
+		baseURL:    "http://authz-service",
+		privileges: map[string]map[string]CompanyPrivileges{},
+	}
+	for _, opt := range opts {
+		opt(handler)
+	}
+	return handler
+}
+
+// Fetch the initial set of privileges from an authz-service
+func (h *PrivilegeHandler) Fetch() error {
+	resp, err := h.client.Get(fmt.Sprintf("%s/authz", h.baseURL))
+	if err != nil {
+		return err
+	}
+
+	buff, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return err
+	}
+
+	err = json.Unmarshal(buff, &h.privileges)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// Process privilege-related events and update the internal state
+func (h *PrivilegeHandler) Process(msg interface{}) bool {
+	if ev, ok := msg.(*PrivilegeAdded); ok {
+		h.setPrivileges(ev)
+		return true
+	}
+	return false
+}
+
+func (h *PrivilegeHandler) setPrivileges(ev *PrivilegeAdded) {
+	if priv, exists := h.privileges[ev.Email]; exists {
+		priv[ev.CompanyID] = CompanyPrivileges{
+			Admin:      ev.Admin,
+			Company:    ev.Company,
+			Consumer:   ev.Consumer,
+			Time:       ev.Time,
+			Invoicing:  ev.Invoicing,
+			Accounting: ev.Accounting,
+			Supplier:   ev.Supplier,
+		}
+	} else {
+		h.privileges[ev.Email] = map[string]CompanyPrivileges{
+			ev.CompanyID: {},
+		}
+		h.setPrivileges(ev)
+	}
+}
+
+// CompaniesByUser return a slice of company ids matching the provided email and predicate func
+func (h *PrivilegeHandler) CompaniesByUser(email string, predicate func(privileges CompanyPrivileges) bool) []string {
+	var result []string
+	if p, exists := h.privileges[email]; exists {
+		for k, v := range p {
+			if predicate(v) {
+				result = append(result, k)
+			}
+		}
+	}
+	return result
+}