this packaging seems to work

README.md

@@ -1,5 +1,28 @@
 partdb-labeler
 ==============
 
-Connects to partdb.alfter.us, grabs a selected part, and formats a label to
-be printed on an EPL2-compatible printer (such as the Zebra LP2844).
+![example](./doc/example.jpg)
+
+Connects to a [PartDB](https://github.com/Part-DB/Part-DB-server) server, grabs info for a selected part, and formats a label to
+be printed on an EPL2-compatible label printer.  Command-line options enable configuration of the label size, server to use, 
+and more.
+
+Why did I write this?
+---------------------
+
+PartDB has a label generator built-in, but it only produces PDFs that must then be rasterized and printed.  This works well 
+enough if you're sending labels to a laser printer, but I found that QR codes small enough to fit on the label stock I wanted
+to use weren't scannable.  This generator speaks EPL2, one of the languages used by Zebra label printers, to produce 
+precisely-formatted labels with QR codes that scan easily with your phone or a dedicated barcode scanner.
+
+Compatibility
+-------------
+
+So far, it's been tested with two Zebra printers: an LP2844 and a GK420t.  The LP2844 was driven by an Arch Linux system with
+a CUPS print queue feeding it through a network print server.  The GK420t was driven by a Windows 11 system, connected to the
+printer via USB.  
+
+Usage
+-----
+
+```python -m partdb-labeler -h``` will show you the available options.

label.py

@@ -1,87 +0,0 @@
-#!/usr/bin/env python
-import requests
-from zebra import Zebra
-import qrcode
-from math import ceil, floor
-from PIL import Image
-import textwrap
-from sys import argv
-
-# make substitutions for characters not in CP437
-
-def subst(s):
-    repl={}
-    repl["®"]="(R)"
-    repl["©"]="(C)"
-    repl["Ω"]="Ω" # U+2126 -> U+03A9, which is in CP437
-    out=""
-    for i in s:
-        try:
-            out=out+repl[i]
-        except:
-            out=out+i
-    return out
-
-# filter out characters not in selected codepage
-# (printer uses CP437)
-
-def filter(s, cp):
-    out=""
-    for i in s:
-        try:
-            i.encode(cp)
-            out=out+i
-        except:
-            pass
-    return out
-
-# render a line of text at coordinates
-# return coordinates of next line
-
-def textline(s, loc, fontnum):
-    pass
-
-label_width=2 # inches
-label_height=1 #inches
-id=argv[1]
-api_key="tcp_673fc81f0b7837ca4c029fbd6536b27742eb8b742eba27bf547c8136dc6a84f8" # anonymous read-only
-
-url=f"https://partdb.alfter.us/api/parts/{id}"
-headers={}
-headers["Accept"]="application/json"
-headers["Authorization"]=f"Bearer {api_key}"
-part=requests.get(url, headers=headers).json()
-
-# print(f"name: {part["name"]}")
-# print(f"description: {part["description"]}")
-# print(f"manufacturer: {part["manufacturer"]["name"]}")
-# print(f"MPN: {part["manufacturer_product_number"]}")
-# print(f"IPN: {part["ipn"]}")
-# print(f"URL: https://partdb.alfter.us/en/part/{id}")
-
-z=Zebra("lp2844")
-z.output(f"q{floor(203*label_width)}\n") #, label_height=(floor(203*label_height),0))
-z.output("N\n")
-
-qr = qrcode.QRCode(
-    box_size=4,
-    border=2,
-)
-qr.add_data(url)
-qr.make(fit=True)
-img = qr.make_image().copy()
-padded=Image.new(mode="1", size=(8*ceil(img.width/8),img.height), color="white")
-padded.paste(im=img, box=(0,0,img.width,img.height))
-z.output(f"GW10,10,{ceil(padded.width/8)},{padded.height},{padded.tobytes().decode("cp437")}\n")
-
-x=15+8*ceil(padded.width/8)
-z.output(f"A{x},20,0,5,1,1,N,\"{part["ipn"]}\"\n")
-z.output(f"A{x},80,0,2,1,1,N,\"{filter(part["manufacturer_product_number"], "cp437")}\"\n")
-z.output(f"A{x},98,0,2,1,1,N,\"{filter(part["manufacturer"]["name"], "cp437")}\"\n")
-
-y=116+28
-for line in textwrap.wrap(filter(subst(part["description"]), "cp437"), width=floor((floor(203*label_width)-40)/10)):
-    z.output(f"A{10},{y},0,1,1,1,N,\"{line}\"\n")
-    y=y+14
-
-z.output("P1\n")

partdb-labeler.py

@@ -0,0 +1,174 @@
+#!/usr/bin/env python
+import requests
+from zebra import Zebra
+import qrcode
+from math import ceil, floor
+from PIL import Image
+import textwrap
+import argparse
+
+parser=argparse.ArgumentParser()
+parser.add_argument("id", help="part ID", type=int)
+parser.add_argument("-x", help="label width, in inches (default: 2\")", type=float)
+parser.add_argument("-y", help="label height, in inches (default: 1\")", type=float)
+parser.add_argument("-g", help="label gap, in inches (default: 0.118\")", type=float)
+parser.add_argument("-q", help="send to selected print queue instead of stdout")
+parser.add_argument("-p", help="PartDB base URL (default: https://partdb.alfter.us)")
+parser.add_argument("-k", help="PartDB API key (default: anonymous key for partdb.alfter.us)")
+parser.add_argument("-r", help="printer resolution (203 or 300; default: 203 dpi)", type=int)
+args=parser.parse_args()
+id=args.id
+if args.x==None:
+    label_width=2
+else:
+    label_width=args.x
+if args.y==None:
+    label_height=1
+else:
+    label_height=args.y
+if args.g==None:
+    label_gap=0.118
+else:
+    label_gap=args.g
+if args.q==None:
+    queue="zebra_python_unittest"
+else:
+    queue=args.q
+if args.p==None:
+    base_url="https://partdb.alfter.us"
+else:
+    base_url=args.p
+if args.k==None:
+    api_key="tcp_673fc81f0b7837ca4c029fbd6536b27742eb8b742eba27bf547c8136dc6a84f8"
+else:
+    api_key=args.k
+if args.r==None:
+    res=203
+else:
+    res=args.r
+    if res!=203 and res!=300:
+        raise ValueError("valid resolution options are 203 and 300")
+
+# width and height for built-in monospace fonts (includes whitespace)
+
+font_metrics={}
+font_metrics[1]=(10,14)
+font_metrics[2]=(12,18)
+font_metrics[3]=(14,22)
+font_metrics[4]=(16,26)
+font_metrics[5]=(34,50)
+
+# make substitutions for characters not in CP437
+
+def subst(s):
+    repl={}
+    repl["®"]="(R)"
+    repl["©"]="(C)"
+    repl["Ω"]="Ω" # U+2126 -> U+03A9, which is in CP437
+    repl["±"]="+/-"
+    out=""
+    for i in s:
+        try:
+            out=out+repl[i]
+        except:
+            out=out+i
+    return out
+
+# filter out characters not in selected codepage
+# (printer uses CP437)
+
+def filter(s, cp):
+    out=""
+    for i in s:
+        try:
+            i.encode(cp)
+            out=out+i
+        except:
+            pass
+    return out
+
+# handle escape characters in strings to be printed
+
+def esc(s):
+    out=""
+    for i in s:
+        if i=="\"":
+            out=out+"\\\""
+        elif i=="\\":
+            out=out+"\\\\"
+        else:
+            out=out+i
+    return out
+
+# render a line of text at coordinates
+# return coordinates of next line
+
+def textline(s, loc, fontnum):
+    z.output(f"A{loc[0]},{loc[1]},0,{fontnum},1,1,N,\"{esc(filter(subst(s), "cp437"))}\"\n")
+    return (loc[0], loc[1]+font_metrics[fontnum][1])
+
+# wrap text in a bounding box at coordinates
+# return coordinates of next line and any unused text
+
+def textbox(s, loc, bbox, fontnum):
+    wrapped=textwrap.wrap(filter(subst(s), "cp437"), width=floor(bbox[0]/font_metrics[fontnum][0]))
+    line=0
+    while line*font_metrics[fontnum][1]<bbox[1] and line<len(wrapped):
+        loc=textline(wrapped[line], loc, fontnum)
+        line=line+1
+    return loc, " ".join(wrapped[line:])
+
+# render a QR code at coordinates
+# return size (single value, since QR codes are square)
+
+def qr(s, loc, mul, brdr):
+    qr = qrcode.QRCode(
+        box_size=mul,
+        border=brdr,
+    )
+    qr.add_data(s)
+    qr.make(fit=True)
+    img = qr.make_image().copy()
+    padded=Image.new(mode="1", size=(8*ceil(img.width/8),img.height), color="white")
+    padded.paste(im=img, box=(0,0,img.width,img.height))
+    z.output(f"GW10,10,{ceil(padded.width/8)},{padded.height},{padded.tobytes().decode("cp437")}\n")
+    return img.height
+
+# look up the part
+
+url=f"{base_url}/api/parts/{id}"
+headers={}
+headers["Accept"]="application/json"
+if api_key!=None:
+    headers["Authorization"]=f"Bearer {api_key}"
+part=requests.get(url, headers=headers).json()
+
+# render a label for it
+
+label_width=floor(label_width*res)
+label_height=floor(label_height*res)
+label_gap=floor(label_gap*res)
+
+z=Zebra(queue)
+z.output(f"q{label_width}\n") 
+if (args.y!=None and args.g!=None):
+    z.output(f"Q{label_height},{label_gap}\n")
+z.output("N\n")
+
+if res==300:
+    qr_size=qr(f"{base_url}/en/part/{id}", (10, 10), 6, 3)
+else:
+    qr_size=qr(f"{base_url}/en/part/{id}", (10, 10), 4, 2)
+
+loc=(15+qr_size, 20)
+loc=textline(part["ipn"], loc, 5)
+
+loc, excess=textbox(f"{part["manufacturer"]["name"]} {part["manufacturer_product_number"]}", loc, (label_width-loc[0]-10, label_height-loc[1]-10), 2)
+
+avail_y=floor((20+qr_size-loc[1])/font_metrics[2][1])*font_metrics[2][1]
+loc, excess=textbox(part["description"], loc, (label_width-loc[0]-10, avail_y), 2)
+if excess!="":
+    loc=(10, loc[1])
+    loc, excess=textbox(excess, loc, (label_width-20, label_height-loc[1]), 2)
+
+z.output("P1\n")

pyproject.toml

@@ -0,0 +1,20 @@
+[build-system]
+requires = ["flit_core >=3.2,<4"]
+build-backend = "flit_core.buildapi"
+
+[project]
+name = "partdb-labeler"
+authors = [
+	{name="Scott Alfter", email="scott@alfter.us"}
+]
+description = "PartDB Labeler"
+version = "0.1.0"
+readme = "README.md"
+dependencies = ["requests", "zebra", "qrcode", "pillow"]
+
+[project.urls]
+Home="https://gitlab.alfter.us/salfter/partdb-labeler"
+
+[tool.flit.module]
+name="partdb-labeler"
+