DO-90/fixed_ssh_connect (#6)

*Update git class
* Add jenkins class

src/tech/avroid/scm/Git.groovy

@@ -6,9 +6,18 @@ package tech.avroid.scm
 class Git implements Serializable {
 
     private Script script
+    private String creds
 
+    // Deprecated constructor
+    // TODO: remove from all Jenkinsfiles
     Git(Script script) {
         this.script = script
+        this.creds = script.env.JENKINS_GIT_CREDENTIALS_SSH
+    }
+
+    Git(Script script, String creds) {
+        this.script = script
+        this.creds = creds
     }
 
      /** get current Branch name
@@ -23,7 +32,7 @@ class Git implements Serializable {
     }
 
     /**
-     * Method to clone a Git repository
+     * Method clones a Git repository
      * @param args Map - Arguments for cloning
      *   - urlRepo: String - HTTP URL of the repository
      *   - branch: String - Branch name, default "main"
@@ -56,13 +65,94 @@ class Git implements Serializable {
           extensions: [[$class: 'RelativeTargetDirectory', relativeTargetDir: "${args.path}"],
                        [$class: 'SubmoduleOption', disableSubmodules: args.disableSubmodules,
                          recursiveSubmodules: args.recursiveSubmodules,
-						 parentCredentials: args.parentCredentials,
-						 trackingSubmodules: args.trackingSubmodules]],
-                         userRemoteConfigs: [[url: "${args.urlRepo}"]]
+                         parentCredentials: args.parentCredentials,
+                         trackingSubmodules: args.trackingSubmodules]],
+                         userRemoteConfigs: [[credentialsId: this.creds,
+                                              url: "${args.urlRepo}"]]
         ])
 
         if (args.listFiles) {
             this.script.sh "ls -la ${args.path}"
         }
     }
+
+    /**
+     * Method set user.name and user.mail for current repository
+     * @param String gitUserName
+     * @param String gitUserMail
+     */
+    public config(String gitUserName = "jenkins", String gitUserMail = "jenkins@example.com") {
+        script.sh """
+            git config user.name ${gitUserName}
+            git config user.email ${gitUserMail}
+        """
+    }
+
+    /**
+      * Method executes command "git add"
+      * @param List    fileContents - files for add to git. If empty than add all files in repository
+      */
+    public add(List fileContents = ["."]) {
+        fileContents.each { fileContent ->
+            script.sh """
+                git add ${fileContent}
+            """
+        }
+    }
+    
+    /**
+      * Method executes command "git commit -m"
+      * @param String Message - git commit message
+      */
+    public commit(String message) {
+        script.sh """
+            git commit -m "${message}"
+        """
+    }
+
+    /**
+      * Method executes command "git push"
+      */
+    public push() {
+        script.sshagent([this.creds]) {
+            script.sh """
+                git push
+            """
+        }
+    }
+
+    /**
+      * Method executes command "git checkout". 
+      * @param String branch - git branch. If empty, equals this.getBranch()
+      */
+    public checkout(String branch = this.getBranch()) {
+        script.sh """
+            git checkout ${branch}
+        """
+    }
+
+    /**
+      * Method executes command "git log".
+      * @param Map args:
+      *     - int Count: count of commits
+      *        - String format: format of output (see git log --help) 
+      */
+    public String log(Map args = [:]) {
+        Map defaultArgs = [
+            count: -1,
+            format: '',
+        ]
+
+        defaultArgs.each { k, v ->
+            if (args[k] == null || args[k] == '' || args[k] == []) {
+                args[k] = v
+            }
+        }
+        
+        if (args.format != '') {
+            args.format = "--format=\"${args.format}\""
+        }
+
+        return this.script.sh(script: "git log -n $args.count $args.format", returnStdout: true).trim()
+    }
 }