MF-1535 - Add API keys functions to SDK (#1536)

* Add API keys to sdk.

Signed-off-by: Filip Bugarski <filipbugarski@gmail.com>

* Add issue key

Signed-off-by: Filip Bugarski <filipbugarski@gmail.com>

* Fix typo

Signed-off-by: Filip Bugarski <filipbugarski@gmail.com>

* Fix comments

Signed-off-by: Filip Bugarski <filipbugarski@gmail.com>

* Remove unused code

Signed-off-by: Filip Bugarski <filipbugarski@gmail.com>

* Fix typo

Signed-off-by: Filip Bugarski <filipbugarski@gmail.com>

pkg/sdk/go/keys.go

@@ -0,0 +1,98 @@
+package sdk
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+
+	"github.com/mainflux/mainflux/pkg/errors"
+)
+
+const keysEndpoint = "keys"
+
+func (sdk mfSDK) Issue(token string, k Key) (issueKeyRes, error) {
+	data, err := json.Marshal(k)
+	if err != nil {
+		return issueKeyRes{}, err
+	}
+
+	url := fmt.Sprintf("%s/%s", sdk.authURL, keysEndpoint)
+
+	req, err := http.NewRequest(http.MethodPost, url, bytes.NewReader(data))
+	if err != nil {
+		return issueKeyRes{}, err
+	}
+
+	resp, err := sdk.sendRequest(req, token, string(CTJSON))
+	if err != nil {
+		return issueKeyRes{}, err
+	}
+	defer resp.Body.Close()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return issueKeyRes{}, err
+	}
+
+	if resp.StatusCode != http.StatusCreated {
+		return issueKeyRes{}, errors.Wrap(ErrFailedCreation, errors.New(resp.Status))
+	}
+
+	var key issueKeyRes
+	if err := json.Unmarshal(body, &key); err != nil {
+		return issueKeyRes{}, err
+	}
+
+	return key, nil
+}
+
+func (sdk mfSDK) Revoke(id, token string) error {
+	url := fmt.Sprintf("%s/%s/%s", sdk.authURL, keysEndpoint, id)
+	req, err := http.NewRequest(http.MethodDelete, url, nil)
+	if err != nil {
+		return err
+	}
+
+	resp, err := sdk.sendRequest(req, token, string(CTJSON))
+	if err != nil {
+		return err
+	}
+
+	if resp.StatusCode != http.StatusNoContent {
+		return errors.Wrap(ErrFailedRemoval, errors.New(resp.Status))
+	}
+
+	return nil
+}
+
+func (sdk mfSDK) RetrieveKey(id, token string) (retrieveKeyRes, error) {
+	url := fmt.Sprintf("%s/%s/%s", sdk.authURL, keysEndpoint, id)
+	req, err := http.NewRequest(http.MethodGet, url, nil)
+	if err != nil {
+		return retrieveKeyRes{}, err
+	}
+
+	resp, err := sdk.sendRequest(req, token, string(CTJSON))
+	if err != nil {
+		return retrieveKeyRes{}, err
+	}
+	defer resp.Body.Close()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return retrieveKeyRes{}, err
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return retrieveKeyRes{}, errors.Wrap(ErrFailedFetch, errors.New(resp.Status))
+	}
+
+	var key retrieveKeyRes
+	if err := json.Unmarshal(body, &key); err != nil {
+		return retrieveKeyRes{}, err
+	}
+
+	return key, nil
+}

pkg/sdk/go/responses.go

@@ -3,7 +3,12 @@
 
 package sdk
 
-import "github.com/mainflux/mainflux/pkg/transformers/senml"
+import (
+	"net/http"
+	"time"
+
+	"github.com/mainflux/mainflux/pkg/transformers/senml"
+)
 
 type tokenRes struct {
 	Token string `json:"token,omitempty"`
@@ -55,3 +60,43 @@ type MembersPage struct {
 	Members []Member `json:"members"`
 	pageRes
 }
+
+type issueKeyRes struct {
+	ID        string     `json:"id,omitempty"`
+	Value     string     `json:"value,omitempty"`
+	IssuedAt  time.Time  `json:"issued_at,omitempty"`
+	ExpiresAt *time.Time `json:"expires_at,omitempty"`
+}
+
+func (res issueKeyRes) Code() int {
+	return http.StatusCreated
+}
+
+func (res issueKeyRes) Headers() map[string]string {
+	return map[string]string{}
+}
+
+func (res issueKeyRes) Empty() bool {
+	return res.Value == ""
+}
+
+type retrieveKeyRes struct {
+	ID        string     `json:"id,omitempty"`
+	IssuerID  string     `json:"issuer_id,omitempty"`
+	Subject   string     `json:"subject,omitempty"`
+	Type      uint32     `json:"type,omitempty"`
+	IssuedAt  time.Time  `json:"issued_at,omitempty"`
+	ExpiresAt *time.Time `json:"expires_at,omitempty"`
+}
+
+func (res retrieveKeyRes) Code() int {
+	return http.StatusOK
+}
+
+func (res retrieveKeyRes) Headers() map[string]string {
+	return map[string]string{}
+}
+
+func (res retrieveKeyRes) Empty() bool {
+	return false
+}

pkg/sdk/go/sdk.go

@@ -7,6 +7,7 @@ import (
 	"crypto/tls"
 	"errors"
 	"net/http"
+	"time"
 )
 
 const (
@@ -109,12 +110,21 @@ type Channel struct {
 	Metadata map[string]interface{} `json:"metadata,omitempty"`
 }
 
-//Member represents mainflux member.
+// Member represents group member.
 type Member struct {
 	ID   string
 	Type string
 }
 
+type Key struct {
+	ID        string
+	Type      uint32
+	IssuerID  string
+	Subject   string
+	IssuedAt  time.Time
+	ExpiresAt time.Time
+}
+
 // SDK contains Mainflux API.
 type SDK interface {
 	// CreateUser registers mainflux user.
@@ -256,6 +266,15 @@ type SDK interface {
 
 	// RevokeCert revokes certificate with certID for thing with thingID
 	RevokeCert(thingID, certID, token string) error
+
+	// Issue issues a new key, returning its token value alongside.
+	Issue(token string, key Key) (issueKeyRes, error)
+
+	// Revoke removes the key with the provided ID that is issued by the user identified by the provided key.
+	Revoke(token, id string) error
+
+	// RetrieveKey retrieves data for the key identified by the provided ID, that is issued by the user identified by the provided key.
+	RetrieveKey(token, id string) (retrieveKeyRes, error)
 }
 
 type mfSDK struct {