[next] Provide less magic around the display (#1673)

pyscript.core/src/core.js

@@ -36,7 +36,7 @@ else {
 if (/^https?:\/\//.test(config)) config = await fetch(config).then(getText);
 
 // generic helper to disambiguate between custom element and script
-const isScript = (element) => element.tagName === "SCRIPT";
+const isScript = ({ tagName }) => tagName === "SCRIPT";
 
 // helper for all script[type="py"] out there
 const before = (script) => {
@@ -91,14 +91,12 @@ const registerModule = ({ XWorker: $XWorker, interpreter, io }) => {
     }
 
     // enrich the Python env with some JS utility for main
-    defineProperty(globalThis, "_pyscript", {
-        value: {
-            PyWorker,
-            get id() {
-                return isScript(currentElement)
-                    ? currentElement.target.id
-                    : currentElement.id;
-            },
+    interpreter.registerJsModule("_pyscript_js", {
+        PyWorker,
+        get target() {
+            return isScript(currentElement)
+                ? currentElement.target.id
+                : currentElement.id;
         },
     });
 

pyscript.core/src/stdlib/pyscript.js

@@ -4,5 +4,5 @@ export default {
     "__init__.py": "import js as window\n\nIS_WORKER = not hasattr(window, \"document\")\n\nif IS_WORKER:\n    from polyscript import xworker as _xworker\n\n    window = _xworker.window\n    document = window.document\n    sync = _xworker.sync\nelse:\n    document = window.document\n",
     "display.py": "import base64\nimport html\nimport io\nimport re\n\nfrom . import document, window\n\n_MIME_METHODS = {\n    \"__repr__\": \"text/plain\",\n    \"_repr_html_\": \"text/html\",\n    \"_repr_markdown_\": \"text/markdown\",\n    \"_repr_svg_\": \"image/svg+xml\",\n    \"_repr_png_\": \"image/png\",\n    \"_repr_pdf_\": \"application/pdf\",\n    \"_repr_jpeg_\": \"image/jpeg\",\n    \"_repr_latex\": \"text/latex\",\n    \"_repr_json_\": \"application/json\",\n    \"_repr_javascript_\": \"application/javascript\",\n    \"savefig\": \"image/png\",\n}\n\n\ndef _render_image(mime, value, meta):\n    # If the image value is using bytes we should convert it to base64\n    # otherwise it will return raw bytes and the browser will not be able to\n    # render it.\n    if isinstance(value, bytes):\n        value = base64.b64encode(value).decode(\"utf-8\")\n\n    # This is the pattern of base64 strings\n    base64_pattern = re.compile(\n        r\"^([A-Za-z0-9+/]{4})*([A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{2}==)?$\"\n    )\n    # If value doesn't match the base64 pattern we should encode it to base64\n    if len(value) > 0 and not base64_pattern.match(value):\n        value = base64.b64encode(value.encode(\"utf-8\")).decode(\"utf-8\")\n\n    data = f\"data:{mime};charset=utf-8;base64,{value}\"\n    attrs = \" \".join(['{k}=\"{v}\"' for k, v in meta.items()])\n    return f'<img src=\"{data}\" {attrs}></img>'\n\n\ndef _identity(value, meta):\n    return value\n\n\n_MIME_RENDERERS = {\n    \"text/plain\": html.escape,\n    \"text/html\": _identity,\n    \"image/png\": lambda value, meta: _render_image(\"image/png\", value, meta),\n    \"image/jpeg\": lambda value, meta: _render_image(\"image/jpeg\", value, meta),\n    \"image/svg+xml\": _identity,\n    \"application/json\": _identity,\n    \"application/javascript\": lambda value, meta: f\"<script>{value}<\\\\/script>\",\n}\n\n\ndef _eval_formatter(obj, print_method):\n    \"\"\"\n    Evaluates a formatter method.\n    \"\"\"\n    if print_method == \"__repr__\":\n        return repr(obj)\n    elif hasattr(obj, print_method):\n        if print_method == \"savefig\":\n            buf = io.BytesIO()\n            obj.savefig(buf, format=\"png\")\n            buf.seek(0)\n            return base64.b64encode(buf.read()).decode(\"utf-8\")\n        return getattr(obj, print_method)()\n    elif print_method == \"_repr_mimebundle_\":\n        return {}, {}\n    return None\n\n\ndef _format_mime(obj):\n    \"\"\"\n    Formats object using _repr_x_ methods.\n    \"\"\"\n    if isinstance(obj, str):\n        return html.escape(obj), \"text/plain\"\n\n    mimebundle = _eval_formatter(obj, \"_repr_mimebundle_\")\n    if isinstance(mimebundle, tuple):\n        format_dict, _ = mimebundle\n    else:\n        format_dict = mimebundle\n\n    output, not_available = None, []\n    for method, mime_type in reversed(_MIME_METHODS.items()):\n        if mime_type in format_dict:\n            output = format_dict[mime_type]\n        else:\n            output = _eval_formatter(obj, method)\n\n        if output is None:\n            continue\n        elif mime_type not in _MIME_RENDERERS:\n            not_available.append(mime_type)\n            continue\n        break\n    if output is None:\n        if not_available:\n            window.console.warn(\n                f\"Rendered object requested unavailable MIME renderers: {not_available}\"\n            )\n        output = repr(output)\n        mime_type = \"text/plain\"\n    elif isinstance(output, tuple):\n        output, meta = output\n    else:\n        meta = {}\n    return _MIME_RENDERERS[mime_type](output, meta), mime_type\n\n\ndef _write(element, value, append=False):\n    html, mime_type = _format_mime(value)\n    if html == \"\\\\n\":\n        return\n\n    if append:\n        out_element = document.createElement(\"div\")\n        element.append(out_element)\n    else:\n        out_element = element.lastElementChild\n        if out_element is None:\n            out_element = element\n\n    if mime_type in (\"application/javascript\", \"text/html\"):\n        script_element = document.createRange().createContextualFragment(html)\n        out_element.append(script_element)\n    else:\n        out_element.innerHTML = html\n\n\ndef display(*values, target=None, append=True):\n    element = document.getElementById(target)\n    for v in values:\n        _write(element, v, append=append)\n"
   },
-  "pyscript.py": "# export only what we want to expose as `pyscript` module\n# but not what is WORKER/MAIN dependent\nfrom _pyscript import window, document, IS_WORKER\n\n# this part is needed to disambiguate between MAIN and WORKER\nif IS_WORKER:\n    # in workers the display does not have a default ID\n    # but there is a sync utility from xworker\n    from _pyscript.display import display\n    from _pyscript import sync\nelse:\n    # in MAIN both PyWorker and a runtime currentScript.id exist\n    # so these are both exposed and the display, if imported,\n    # will point at the right script as default target\n    PyWorker = window._pyscript.PyWorker\n\n    def __getattr__(attribute_name):\n        if attribute_name == \"display\":\n            from _pyscript.display import display\n\n            id = window._pyscript.id\n            return lambda *values, target=id, append=True: display(\n                *values, target=target, append=append\n            )\n        raise AttributeError(f\"'{__name__}' has no attribute '{attribute_name}'\")\n"
+  "pyscript.py": "# export only what we want to expose as `pyscript` module\n# but not what is WORKER/MAIN dependent\nfrom _pyscript import window, document, IS_WORKER\nfrom _pyscript.display import display as _display\n\n# this part is needed to disambiguate between MAIN and WORKER\nif IS_WORKER:\n    # in workers the display does not have a default ID\n    # but there is a sync utility from xworker\n    import polyscript as _polyscript\n    from _pyscript import sync\n\n    def current_target():\n        return _polyscript.target\n\nelse:\n    # in MAIN both PyWorker and current element target exist\n    # so these are both exposed and the display will use,\n    # if not specified otherwise, such current element target\n    import _pyscript_js\n\n    PyWorker = _pyscript_js.PyWorker\n\n    def current_target():\n        return _pyscript_js.target\n\n\n# the display provides a handy default target either in MAIN or WORKER\ndef display(*values, target=None, append=True):\n    if target is None:\n        target = current_target()\n\n    return _display(*values, target=target, append=append)\n"
 };

pyscript.core/src/stdlib/pyscript.py

@@ -1,25 +1,33 @@
 # export only what we want to expose as `pyscript` module
 # but not what is WORKER/MAIN dependent
 from _pyscript import window, document, IS_WORKER
+from _pyscript.display import display as _display
 
 # this part is needed to disambiguate between MAIN and WORKER
 if IS_WORKER:
     # in workers the display does not have a default ID
     # but there is a sync utility from xworker
-    from _pyscript.display import display
+    import polyscript as _polyscript
     from _pyscript import sync
+
+    def current_target():
+        return _polyscript.target
+
 else:
-    # in MAIN both PyWorker and a runtime currentScript.id exist
-    # so these are both exposed and the display, if imported,
-    # will point at the right script as default target
-    PyWorker = window._pyscript.PyWorker
+    # in MAIN both PyWorker and current element target exist
+    # so these are both exposed and the display will use,
+    # if not specified otherwise, such current element target
+    import _pyscript_js
 
-    def __getattr__(attribute_name):
-        if attribute_name == "display":
-            from _pyscript.display import display
+    PyWorker = _pyscript_js.PyWorker
 
-            id = window._pyscript.id
-            return lambda *values, target=id, append=True: display(
-                *values, target=target, append=append
-            )
-        raise AttributeError(f"'{__name__}' has no attribute '{attribute_name}'")
+    def current_target():
+        return _pyscript_js.target
+
+
+# the display provides a handy default target either in MAIN or WORKER
+def display(*values, target=None, append=True):
+    if target is None:
+        target = current_target()
+
+    return _display(*values, target=target, append=append)