Generate list of image types to create programmatically in the Web UI (#850)

* Generate list of image types to create programmatically based on rascsi capabilities, rather than a hard-coded list in the Web UI.

* Add explicit sorting of dicts for display in the Web UI, to avoid random order in certain environments.

* Remove redundant sorting line, and add code comments.

* Add helptext for the SCSI-1 image type

python/web/src/templates/index.html

@@ -336,7 +336,7 @@
         <td>
             <form action="/scsi/attach_device" method="post">
                 <input name="type" type="hidden" value="{{ type }}">
-                {% for key, value in device_types[type]["params"].items() %}
+                {% for key, value in device_types[type]["params"] | dictsort %}
                 <label for="{{ key }}">{{ key }}:</label>
                 {% if value.isnumeric() %}
                 <input name="{{ key }}" type="number" value="{{ value }}">
@@ -544,9 +544,10 @@
     </summary>
     <ul>
         <li>{{ _("The Generic Hard Disk image type is recommended for most computer platforms.") }}</li>
-        <li>{{ _("APPLE GENUINE is appropriate for Apple Macintosh computers.") }}</li>
-        <li>{{ _("NEC GENUINE is appropriate for NEC PC-98 computers.") }}</li>
-        <li>{{ _("The Generic Removable Disk image type can be used with SCSI floppy drives, SyQuest drives, Zip drives etc.") }}</li>
+        <li>{{ _("The Apple image type improves compatibility with Apple Macintosh computers.") }}</li>
+        <li>{{ _("The NEC image type improves compatibility with NEC PC-98 computers.") }}</li>
+        <li>{{ _("The SCSI-1 image type makes RaSCSI behave like a legacy SCSI-1 device, which may improve compatibility with very old SCSI controllers.") }}</li>
+        <li>{{ _("The Removable Disk image type can be used with SCSI floppy drives, SyQuest drives, Zip drives, etc.") }}</li>
     </ul>
 </details>
 <table style="border: none">
@@ -557,18 +558,11 @@
                 <input name="file_name" placeholder="{{ _("File Name") }}" required="" type="text">
                 <label for="type">{{ _("Type:") }}</label>
                 <select name="type">
-                    <option value="hds">
-                    {{ _("SCSI Hard Disk image (Generic) [.hds]") }}
-                    </option>
-                    <option value="hda">
-                    {{ _("SCSI Hard Disk image (APPLE GENUINE) [.hda]") }}
-                    </option>
-                    <option value="hdn">
-                    {{ _("SCSI Hard Disk image (NEC GENUINE) [.hdn]") }}
-                    </option>
-                    <option value="hdr">
-                    {{ _("SCSI Removable Disk image (Generic) [.hdr]") }}
+                    {% for key, value in image_suffixes_to_create.items() %}
+                    <option value="{{ key }}">
+                    {{ value }} [.{{ key }}]
                     </option>
+                    {% endfor %}
                 </select>
                 <label for="size">{{ _("Size:") }}</label>
                 <input name="size" type="number" placeholder="{{ _("MB") }}" min="1" max="262144" required>

python/web/src/web.py

@@ -49,6 +49,7 @@ from web_utils import (
     get_valid_scsi_ids,
     map_device_types_and_names,
     get_device_name,
+    map_image_file_descriptions,
     auth_active,
     is_bridge_configured,
     upload_with_dropzonejs,
@@ -133,6 +134,19 @@ def index():
     scsi_ids, recommended_id = get_valid_scsi_ids(devices["device_list"], reserved_scsi_ids)
     formatted_devices = sort_and_format_devices(devices["device_list"])
 
+    image_suffixes_to_create = map_image_file_descriptions(
+        # Here we strip out hdi and nhd, since they are proprietary PC-98 emulator formats
+        # that require a particular header to work. We can't generate them on the fly.
+        # We also reverse the resulting list, in order for hds to be the default in the UI.
+        # This might break if something like 'hdt' etc. gets added in the future.
+        sorted(
+            [suffix for suffix in server_info["schd"] if suffix not in {"hdi", "nhd"}],
+            reverse=True
+            ) +
+        server_info["scrm"] +
+        server_info["scmo"]
+        )
+
     valid_image_suffixes = "." + ", .".join(
         server_info["schd"] +
         server_info["scrm"] +
@@ -174,6 +188,7 @@ def index():
         netinfo=ractl_cmd.get_network_info(),
         device_types=device_types,
         free_disk=int(sys_cmd.disk_space()["free"] / 1024 / 1024),
+        image_suffixes_to_create=image_suffixes_to_create,
         valid_image_suffixes=valid_image_suffixes,
         cdrom_file_suffix=tuple(server_info["sccd"]),
         removable_file_suffix=tuple(server_info["scrm"]),

python/web/src/web_utils.py

@@ -99,6 +99,39 @@ def get_device_name(device_type):
     return device_type
 
 
+def map_image_file_descriptions(file_suffixes):
+    """
+    Takes a (list) of (str) file suffixes for images file types.
+    Returns a (dict) with file suffix and description pairs, both (str)
+    """
+    supported_image_types = {}
+    for suffix in file_suffixes:
+        supported_image_types[suffix] = get_image_description(suffix)
+
+    return supported_image_types
+
+
+# pylint: disable=too-many-return-statements
+def get_image_description(file_suffix):
+    """
+    Takes a three char file suffix (str) file_suffix.
+    Returns the help text description for said file suffix.
+    """
+    if file_suffix == "hds":
+        return _("Hard Disk Image (Generic)")
+    if file_suffix == "hda":
+        return _("Hard Disk Image (Apple)")
+    if file_suffix == "hdn":
+        return _("Hard Disk Image (NEC)")
+    if file_suffix == "hd1":
+        return _("Hard Disk Image (SCSI-1)")
+    if file_suffix == "hdr":
+        return _("Removable Disk Image")
+    if file_suffix == "mos":
+        return _("Magneto-Optical Disk Image")
+    return file_suffix
+
+
 def auth_active(group):
     """
     Inspects if the group defined in (str) group exists on the system.