diff --git a/storage/d4s-storage.js b/storage/d4s-storage.js
new file mode 100644
index 0000000..ed7a860
--- /dev/null
+++ b/storage/d4s-storage.js
@@ -0,0 +1,360 @@
+/**
+ * Base class of <d4s-storage-tree> and <d4s-storage-folder>
+ */
+class D4SStorageHtmlElement extends HTMLElement {
+
+    #d4s = null
+    #d4smissmsg = 'Required d4s-boot-2 component not found'
+
+    //#baseurl = 'https://api.dev.d4science.org'
+    #baseurl = 'https://storagehub.pre.d4science.net/storagehub/workspace'
+
+    constructor() {
+        super()
+    }
+
+    appendStylesheets(root) {
+        const linkElem1 = document.createElement('link')
+        linkElem1.setAttribute('rel', 'stylesheet')
+        linkElem1.setAttribute('href', 'https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/css/bootstrap.min.css')
+        const linkElem2 = document.createElement('link')
+        linkElem2.setAttribute('rel', 'stylesheet')
+        linkElem2.setAttribute('href', 'https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.1.1/css/all.min.css')
+        root.appendChild(linkElem1)
+        root.appendChild(linkElem2)
+    }
+
+    get d4s() {
+        if (this.#d4s == null) {
+            this.#d4s = document.querySelector('d4s-boot-2')
+            if (!this.#d4s) {
+                console.error(this.#d4smissmsg)
+            }
+        }
+        return this.#d4s
+    }
+
+    buildListUrl(id) {
+        return this.#baseurl + '/items/' + id + '/children'
+    }
+
+    get baseUrl() {
+        return this.#baseurl
+    }
+
+    set baseUrl(url) {
+        this.#baseurl = url
+        this.setAttribute("baseurl", url)
+    }
+}
+
+
+/**
+ * Builds storagehub VREFolder tree
+ * <d4s-storage-tree
+ *  /@filelist-id: identifier of d4s-storage-folder component
+ *  /@baseurl: the base endpoint url [defaults to: https://storagehub.pre.d4science.net/storagehub/workspace]
+ */
+window.customElements.define('d4s-storage-tree', class extends D4SStorageHtmlElement {
+
+    #storageFilelistId = null
+
+    #loadedClass = 'loaded'
+    #selectedClass = 'selected'
+    #selectedbgcolor = 'lightgray'
+
+    constructor() {
+        super()
+    }
+
+    /*
+    Notes:
+    API docs: https://gcube.wiki.gcube-system.org/gcube/StorageHub_REST_API
+    Preprod: https://accounts.pre.d4science.org
+    Sample context: %2Fpred4s%2Fpreprod%2FpreVRE
+    User workspace: https://storagehub.pre.d4science.net/storagehub/workspace
+    vrefolder: https://storagehub.pre.d4science.net/storagehub/workspace/vrefolder
+     -> and if "id": "e0cd15d2-0071-43ca-bc42-aef8d80660fe",
+        the tree dir of vrefolder: https://storagehub.pre.d4science.net/storagehub/workspace/items/e0cd15d2-0071-43ca-bc42-aef8d80660fe/children
+        download of a file (domenica.jpg): https://storagehub.pre.d4science.net/storagehub/workspace/items/a5086811-59d1-4230-99fa-98431e820cf1/download
+    */
+    connectedCallback() {
+        const shadowRoot = this.attachShadow({mode: 'open'})
+        this.appendStylesheets(shadowRoot)
+
+        var div = document.createElement('div')
+        const style = `
+            <style>
+                .selected > *:first-child {
+                    background-color: ${this.#selectedbgcolor};
+                }
+                ul, li {
+                    list-style-type: none;
+                }
+                li {
+                    cursor: pointer;
+                }
+            </style>
+        `
+        div.innerHTML = style
+
+        this.d4s.service(
+            this.baseUrl + '/vrefolder',
+            'GET', null,
+            (resp) => {
+                this.parseResponse(div, resp)
+                shadowRoot.appendChild(div)
+            },
+            (err) => { alert(err) }
+        )
+    }
+
+    parseResponse(parentElement, response) {
+        parentElement.classList.add(this.#loadedClass)
+        var ul = document.createElement('ul')
+        ul.classList.add('nested')
+        var jresp = JSON.parse(response)
+        if (jresp.item) {
+            const itemname = jresp.item.displayName
+            const itemid = jresp.item.id
+            const path = this.buildListUrl(itemid)
+            ul.appendChild(this.createListItem(itemname, itemid))
+            parentElement.appendChild(ul)
+
+        } else if (jresp.itemlist) {
+            jresp
+                .itemlist
+                .filter(item => item['@class'].includes('FolderItem'))
+                .forEach(item => {
+                    const itemname = item.name
+                    const itemid = item.id
+                    const path = this.buildListUrl(itemid)
+                    ul.appendChild(this.createListItem(itemname, itemid))
+                })
+            parentElement.appendChild(ul)
+        } else {
+            console.error(jresp)
+        }
+    }
+
+    createListItem(label, id) {
+        var li = document.createElement('li')
+        li.setAttribute('data-id', id)
+        var child = document.createElement('span')
+        child.innerHTML = label
+        li.appendChild(child)
+
+        li.addEventListener('click', (ev) => {
+            ev.stopPropagation()
+            this.select(ev.currentTarget.getAttribute('data-id'))
+        })
+        return li
+    }
+
+    select(id) {
+        var li = this.shadowRoot.querySelector(`*[data-id='${id}']`)
+        this.displayPath(li)
+
+        // if it was already selected then do nothing
+        if (li.classList.contains(this.#selectedClass)) {
+            this.toggleULDisplay(li)
+            return
+        }
+        // switch selected and lists folder contents
+        if (!li.classList.contains(this.#selectedClass)) {
+            const selected = this.shadowRoot.querySelector('.' + this.#selectedClass)
+            if (selected) {
+                selected.classList.remove(this.#selectedClass)
+            }
+            li.classList.add(this.#selectedClass)
+            if (this.#storageFilelistId) {
+                var folder = document.getElementById(this.#storageFilelistId)
+                folder.join(this)
+                folder.list(id)
+            }
+        }
+        if (li.classList.contains(this.#loadedClass)) {
+            return
+        }
+        this.d4s.service(
+            this.buildListUrl(id),
+            'GET', null,
+            (resp) => this.parseResponse(li, resp),
+            (err) => { alert(err) }
+        )
+    }
+
+    displayPath(li) {
+        var curr = li
+        while (curr.parentElement != null) {
+            if (curr.parentElement.tagName == 'UL') {
+                curr.parentElement.style.display = 'block'
+            }
+            curr = curr.parentElement
+        }
+    }
+
+    toggleULDisplay(li) {
+        const ul = li.querySelector('ul')
+        if (ul) {
+            ul.style.display = (ul.style.display === 'none') ? 'block' : 'none'
+        }
+    }
+
+    static get observedAttributes() {
+        return ["base-url", "filelist-id"];
+    }
+
+    attributeChangedCallback(name, oldValue, newValue) {
+        if (oldValue !== newValue) {
+            switch (name) {
+                case "filelist-id":
+                    this.#storageFilelistId = newValue
+                    break
+                case "base-url":
+                    this.baseUrl = newValue
+                    break
+            }
+        }
+    }
+
+    get filelistId() {
+        return this.#storageFilelistId
+    }
+
+    set filelistId(id) {
+        this.#storageFilelistId = id
+        this.setAttribute("filelist-id", id)
+    }
+})
+
+/**
+ * Lists elements in selected folder
+ * 
+ * <d4s-storage-folder
+ *  /@id: specify the id to join this component with storage tree component
+ *  /@baseurl: the base endpoint url [defaults to: https://storagehub.pre.d4science.net/storagehub/workspace]
+ */
+window.customElements.define('d4s-storage-folder', class extends D4SStorageHtmlElement {
+
+    #d4sstorageTree = null
+    #selectedbgcolor = 'lightgray'
+
+    constructor() {
+        super()
+    }
+
+    connectedCallback() {
+        const shadowRoot = this.attachShadow({mode: 'open'})
+        this.appendStylesheets(shadowRoot)
+
+        const style = document.createElement('style')
+        style.innerHTML = `
+            span {
+                cursor: pointer;
+                user-select: none;
+                -moz-user-select: none;
+                -webkit-user-select: none;
+                -ms-user-select: none;
+            }
+        `
+        shadowRoot.appendChild(style)
+        this.createContainer()
+    }
+
+    createContainer() {
+        var div = document.createElement('div')
+        div.classList.add('d4s-folder')
+        var child = this.shadowRoot.querySelector('.d4s-folder')
+        if (child) {
+            this.shadowRoot.removeChild(child)
+        }
+        this.shadowRoot.appendChild(div)
+        return div
+    }
+
+    join(tree) {
+        if (this.#d4sstorageTree == null) {
+            this.#d4sstorageTree = tree
+        }
+    }
+
+    list(folderId) {
+        this.d4s.service(
+            this.buildListUrl(folderId),
+            'GET', null,
+            (resp) => this.parseResponse(resp),
+            (err) => { alert(err) }
+        )
+    }
+
+    parseResponse(response) {
+        const root = this.createContainer()
+        var jresp = JSON.parse(response)
+        if (jresp.itemlist) {
+            jresp.itemlist.forEach(item => root.appendChild(this.createFileRow(item)))
+
+        } else {
+            console.error(jresp)
+        }
+    }
+
+    createFileRow(item) {
+        var div = document.createElement('div')
+        div.classList.add('row')
+        var filename = document.createElement('div')
+        filename.classList.add('col')
+        var name = `<span>${item.name}</span>`
+        filename.innerHTML = this.iconTag(item) + name
+        const isFolder = item['@class'].includes('FolderItem')
+        filename.addEventListener('click', (ev) => {
+            ev.stopPropagation()
+            if (isFolder) {
+                const span = ev.currentTarget.querySelector(':nth-child(2)')
+                if (span) {
+                    span.style = 'background-color: ' + this.#selectedbgcolor
+                }
+                if (this.#d4sstorageTree != null) {
+                    this.#d4sstorageTree.select(item.id)
+                }
+            } else {
+                console.info("Download of " + item.id)
+                this.d4s.download(this.buildDownloadUrl(item.id), item.name)
+            }
+        })
+
+        div.appendChild(filename)
+        return div
+    }
+
+    iconTag(item) {
+        var i = `<i class="fa-regular fa-file fa-fw"></i>`
+        if (item['@class'].includes('FolderItem')) {
+            i = `<i class="fa-regular fa-folder fa-fw"></i>`
+        } else if (item['@class'].includes('ImageFile')) {
+            i = `<i class="fa-regular fa-image fa-fw"></i>`
+        } else if (item['@class'].includes('PDFFileItem')) {
+            i = `<i class="fa-regular fa-file-pdf fa-fw"></i>`
+        }
+        return '<span class="px-2">' + i + '</span>'
+    }
+
+    buildDownloadUrl(id) {
+        return this.baseUrl+ '/items/' + id + '/download'
+    }
+
+    static get observedAttributes() {
+        return ["base-url"];
+    }
+
+    attributeChangedCallback(name, oldValue, newValue) {
+        if (oldValue !== newValue) {
+            switch (name) {
+                case "base-url":
+                    this.baseUrl = newValue
+                    break
+            }
+        }
+    }
+
+})
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