Feat: join_pdf work

bopytex/worker/join_pdf.py

@@ -0,0 +1,17 @@
+import subprocess
+
+def pdfjam(args: dict, deps, output):
+    joining_process = subprocess.Popen(
+        ["pdfjam"] +  deps + ["-o", output],
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
+        universal_newlines=True,
+    )
+    # exit_code is always 66...
+    exit_code = joining_process.wait()
+
+    if  exit_code == 0:
+        yield "pdfjam success"
+    else:
+        yield "pdfjam failed"
+