diff --git a/htdocs/bom/class/api_boms.class.php b/htdocs/bom/class/api_boms.class.php
index 91af888ffd8..7e274e9de9a 100644
--- a/htdocs/bom/class/api_boms.class.php
+++ b/htdocs/bom/class/api_boms.class.php
@@ -2,6 +2,7 @@
 /* Copyright (C) 2015   Jean-François Ferry     <jfefe@aternatik.fr>
  * Copyright (C) 2019 Maxime Kohlhaas <maxime@atm-consulting.fr>
  * Copyright (C) 2020     	Frédéric France		<frederic.france@netlogic.fr>
+ * Copyright (C) 2022     	Christian Humpel		<christian.humpel@live.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -279,6 +280,81 @@ class Boms extends DolibarrApi
 		);
 	}
 
+	/**
+	 * Get lines of an BOM
+	 *
+	 * @param int   $id             Id of BOM
+	 *
+	 * @url	GET {id}/lines
+	 *
+	 * @return array
+	 */
+	public function getLines($id)
+	{
+		if (!DolibarrApiAccess::$user->rights->bom->read) {
+			throw new RestException(401);
+		}
+
+		$result = $this->bom->fetch($id);
+		if (!$result) {
+			throw new RestException(404, 'BOM not found');
+		}
+
+		if (!DolibarrApi::_checkAccessToResource('bom_bom', $this->bom->id)) {
+			throw new RestException(401, 'Access not allowed for login '.DolibarrApiAccess::$user->login);
+		}
+		$this->bom->getLinesArray();
+		$result = array();
+		foreach ($this->bom->lines as $line) {
+			array_push($result, $this->_cleanObjectDatas($line));
+		}
+		return $result;
+	}
+
+	/**
+	 * Add a line to given BOM
+	 *
+	 * @param int   $id             Id of BOM to update
+	 * @param array $request_data   BOMLine data
+	 *
+	 * @url	POST {id}/lines
+	 *
+	 * @return int
+	 */
+	public function postLine($id, $request_data = null)
+	{
+		if (!DolibarrApiAccess::$user->rights->bom->write) {
+			throw new RestException(401);
+		}
+
+		$result = $this->bom->fetch($id);
+		if (!$result) {
+			throw new RestException(404, 'BOM not found');
+		}
+
+		if (!DolibarrApi::_checkAccessToResource('bom_bom', $this->bom->id)) {
+			throw new RestException(401, 'Access not allowed for login '.DolibarrApiAccess::$user->login);
+		}
+
+		$request_data = (object) $request_data;
+
+		$updateRes = $this->bom->addLine(
+			$request_data->fk_product,
+			$request_data->qty,
+			$request_data->qty_frozen,
+			$request_data->disable_stock_change,
+			$request_data->efficiency,
+			$request_data->postion,
+			$request_data->fk_bom_child,
+			$request_data->import_key
+		);
+
+		if ($updateRes > 0) {
+			return $updateRes;
+		} else {
+			throw new RestException(400, $this->bom->error);
+		}
+	}
 
 	// phpcs:disable PEAR.NamingConventions.ValidFunctionName.PublicUnderscore
 	/**
diff --git a/htdocs/bom/class/bom.class.php b/htdocs/bom/class/bom.class.php
index 8adcac855c2..42ced4a2f0e 100644
--- a/htdocs/bom/class/bom.class.php
+++ b/htdocs/bom/class/bom.class.php
@@ -502,6 +502,100 @@ class BOM extends CommonObject
 		//return $this->deleteCommon($user, $notrigger, 1);
 	}
 
+	/**
+	 * Add an BOM line into database (linked to BOM)
+	 *
+	 * @param	int		$fk_product				Id of product
+	 * @param	float	$qty					Quantity
+	 * @param	int		$qty_frozen				Frozen quantity
+	 * @param 	int		$disable_stock_change	Disable stock change on using in MO
+	 * @param	float	$efficiency				Efficiency in MO
+	 * @param	int		$position				Position of BOM-Line in BOM-Lines
+	 * @param	int		$fk_bom_child			Id of BOM Child
+	 * @param	string	$import_key				Import Key
+	 * @return	int								<0 if KO, >0 if OK
+	 */
+	public function addLine($fk_product, $qty, $qty_frozen = 0, $disable_stock_change = 0, $efficiency = 1.0, $position = -1, $fk_bom_child = null, $import_key = null)
+	{
+
+		global $mysoc, $conf, $langs, $user;
+
+		$logtext = "::addLine bomid=$this->id, qty=$qty, fk_product=$fk_product, qty_frozen=$qty_frozen, disable_stock_change=$disable_stock_change, efficiency=$efficiency";
+		$logtext .= ", fk_bom_child=$fk_bom_child, import_key=$import_key";
+		dol_syslog(get_class($this).$logtext, LOG_DEBUG);
+
+		if ($this->statut == self::STATUS_DRAFT) {
+			include_once DOL_DOCUMENT_ROOT.'/core/lib/price.lib.php';
+
+			// Clean parameters
+			if (empty($qty)) {
+				$qty = 0;
+			}
+			if (empty($qty_frozen)) {
+				$qty_frozen = 0;
+			}
+			if (empty($disable_stock_change)) {
+				$disable_stock_change = 0;
+			}
+			if (empty($efficiency)) {
+				$efficiency = 1.0;
+			}
+			if (empty($fk_bom_child)) {
+				$fk_bom_child = null;
+			}
+			if (empty($import_key)) {
+				$import_key = null;
+			}
+			if (empty($position)) {
+				$position = -1;
+			}
+
+			$qty = price2num($qty);
+			$efficiency = price2num($efficiency);
+			$position = price2num($position);
+
+			$this->db->begin();
+
+			// Rank to use
+			$rankToUse = $position;
+			if ($rankToUse == -1) {
+				$rangMax = $this->line_max();
+				$rankToUse = $rangMax + 1;
+			}
+
+			// Insert line
+			$this->line = new BOMLine($this->db);
+
+			$this->line->context = $this->context;
+
+			$this->line->fk_bom = $this->id;
+			$this->line->fk_product = $fk_product;
+			$this->line->qty = $qty;
+			$this->line->qty_frozen = $qty_frozen;
+			$this->line->disable_stock_change = $disable_stock_change;
+			$this->line->efficiency = $efficiency;
+			$this->line->fk_bom_child = $fk_bom_child;
+			$this->line->import_key = $import_key;
+			$this->line->position = $rankToUse;
+
+			$result = $this->line->create($user);
+
+			if ($result > 0) {
+				$this->calculateCosts();
+				$this->db->commit();
+				return $this->line->id;
+			} else {
+				$this->error = $this->line->error;
+				dol_syslog(get_class($this)."::addLine error=".$this->error, LOG_ERR);
+				$this->db->rollback();
+				return -2;
+			}
+		} else {
+			dol_syslog(get_class($this)."::addLine status of BOM must be Draft to allow use of ->addLine()", LOG_ERR);
+			return -3;
+		}
+	}
+
 	/**
 	 *  Delete a line of object in database
 	 *