feat(cli): Add "node show" command (#224)

Also implement the `--node-stats` option to "group show"

Should the stat-generating function `get_stats` stay in
`client.node.stats` or should it be moved to `client.cli` (which
contains general-purpose CLI library functions)?

alpenhorn/cli/group/show.py

@@ -7,6 +7,7 @@
 
 from ...db import StorageGroup, StorageNode
 from ..cli import echo
+from ..node.stats import get_stats
 
 
 @click.command()
@@ -51,19 +52,55 @@ def show(group_name, node_details, node_stats):
     if nodes:
         if node_details or node_stats:
             if node_details:
-                data = [
-                    (
+                details = {
+                    node.id: (
                         node.name,
                         node.host,
                         "Yes" if node.active else "No",
                         node.io_class if node.io_class else "Default",
                     )
                     for node in nodes
+                }
+            if node_stats:
+                stats = get_stats(nodes, False)
+
+            # Make table
+            data = []
+            if node_stats and node_details:
+                headers = [
+                    "Name",
+                    "Host",
+                    "Active",
+                    "I/O Class",
+                    "File Count",
+                    "Total Size",
+                    "% Full",
                 ]
+                for node in nodes:
+                    data.append(
+                        (
+                            *details[node.id],
+                            stats[node.id]["count"],
+                            stats[node.id]["size"],
+                            stats[node.id]["percent"],
+                        )
+                    )
+            elif node_details:
                 headers = ["Name", "Host", "Active", "I/O Class"]
-            if node_stats:
-                # TODO: add --node-stats support when "alpenhorn node stats" is implemented
-                raise NotImplementedError()
+                for node in nodes:
+                    data.append(details[node.id])
+            else:
+                headers = ["Name", "File Count", "Total Size", "% Full"]
+                for node in nodes:
+                    data.append(
+                        (
+                            node.name,
+                            stats[node.id]["count"],
+                            stats[node.id]["size"],
+                            stats[node.id]["percent"],
+                        )
+                    )
+
             echo(tabulate(data, headers=headers))
         else:
             # simple list

alpenhorn/cli/node/__init__.py

@@ -19,6 +19,7 @@
 from .list import list_
 from .modify import modify
 from .rename import rename
+from .show import show
 from .stats import stats
 
 RE_LOCK_FILE = re.compile(r"^\..*\.lock$")
@@ -36,6 +37,7 @@ def cli():
 cli.add_command(list_, "list")
 cli.add_command(modify, "modify")
 cli.add_command(rename, "rename")
+cli.add_command(show, "show")
 cli.add_command(stats, "stats")
 
 

alpenhorn/cli/node/show.py

@@ -0,0 +1,98 @@
+"""alpenhorn node show command"""
+
+import json
+import click
+import peewee as pw
+
+from ...common.util import pretty_bytes
+from ...db import StorageGroup, StorageNode
+from ..cli import echo
+from .stats import get_stats
+
+
+@click.command()
+@click.argument("name", metavar="NAME")
+@click.option("--stats", is_flag=True, help="Show usage stats of the node.")
+def show(name, stats):
+    """Show details of a Storage Node.
+
+    Shows details of the Storage Node named NODE.
+    """
+
+    try:
+        node = StorageNode.get(name=name)
+    except pw.DoesNotExist:
+        raise click.ClickException(f"no such node: {name}")
+
+    if node.storage_type == "A":
+        type_name = "Archive"
+    elif node.storage_type == "T":
+        type_name = "Transport"
+    else:
+        type_name = "-"
+
+    if node.max_total_gb:
+        max_total = pretty_bytes(node.max_total_gb * 2**30)
+    else:
+        max_total = "-"
+
+    if node.min_avail_gb:
+        min_avail = pretty_bytes(node.min_avail_gb * 2**30)
+    else:
+        min_avail = "-"
+
+    if node.avail_gb:
+        avail = pretty_bytes(node.avail_gb * 2**30)
+    else:
+        avail = "-"
+
+    if node.avail_gb_last_checked:
+        last_checked = node.avail_gb_last_checked.ctime() + " UTC"
+    else:
+        last_checked = "???"
+
+    # Print a report
+    echo("   Storage Node: " + node.name)
+    echo("  Storage Group: " + node.group.name)
+    echo("         Active: " + ("Yes" if node.active else "No"))
+    echo("           Type: " + type_name)
+    echo("          Notes: " + (node.notes if node.notes else ""))
+    echo("      I/O Class: " + (node.io_class if node.io_class else "Default"))
+    echo()
+    echo("    Daemon Host: " + (node.host if node.host else ""))
+    echo(" Log-in Address: " + (node.address if node.address else ""))
+    echo("Log-in Username: " + (node.username if node.username else ""))
+    echo()
+    echo("    Auto-Import: " + ("On" if node.auto_import else "Off"))
+    echo(
+        "    Auto-Verify: "
+        + (f"On (Size: {node.auto_verify})" if node.auto_verify else "Off")
+    )
+    echo("      Max Total: " + max_total)
+    echo("      Available: " + avail)
+    echo("  Min Available: " + min_avail)
+    echo("   Last Checked: " + last_checked)
+
+    echo("\nI/O Config:\n")
+    if node.io_config:
+        try:
+            io_config = json.loads(node.io_config)
+            if io_config:
+                # Find length of longest key (but not too long)
+                keylen = min(max([len(key) for key in io_config]), 30)
+                for key, value in io_config.items():
+                    echo("  " + key.rjust(keylen) + ": " + str(value))
+            else:
+                echo("  empty")
+        except json.JSONDecodeError:
+            echo("INVALID (JSON decode error)")
+    else:
+        echo("  none")
+
+    if stats:
+        stats = get_stats([node], False)[node.id]
+
+        echo("\nStats:\n")
+        echo("    Total Files: " + str(stats["count"]))
+        echo("     Total Size: " + stats["size"])
+        echo("          Usage: " + stats["percent"].lstrip() + "%")