composer: Add yum metadata size to size estimate

anaconda also writes the repo metadata to the disk, so take that into
account when estimating the required size.

Resolves: rhbz#1761337

src/pylorax/api/compose.py

@@ -404,6 +404,20 @@ def start_build(cfg, yumlock, gitlock, branch, recipe_name, compose_type, test_m
         raise RuntimeError("Problem depsolving %s: %s" % (recipe["name"], str(e)))
     log.debug("installed_size = %d, template_size=%d", installed_size, template_size)
 
+    with yumlock.lock:
+        repos = yumlock.yb.repos.listEnabled()
+    if not repos:
+        raise RuntimeError("No enabled repos, canceling build.")
+
+    # Anaconda also stores the metadata on the disk once it is partitioned, try to take this into account
+    metadata_size = 0
+    for repo in repos:
+        metadata_size += repo._getRepoXML().length
+        metadata_size += int(repo._getRepoXML().getData("group").size)
+        metadata_size += int(repo._getRepoXML().getData("primary_db").size)
+        metadata_size += int(repo._getRepoXML().getData("updateinfo").size)
+    log.info("installed_size = %d, template_size=%d, metadata_size=%d", installed_size, template_size, metadata_size)
+
     # Minimum LMC disk size is 1GiB, and anaconda bumps the estimated size up by 35% (which doesn't always work).
     installed_size = max(1024**3, int((installed_size+template_size) * 1.4))
     log.debug("/ partition size = %d", installed_size)
@@ -437,11 +451,6 @@ def start_build(cfg, yumlock, gitlock, branch, recipe_name, compose_type, test_m
     # Save a copy of the original kickstart
     shutil.copy(ks_template_path, results_dir)
 
-    with yumlock.lock:
-        repos = yumlock.yb.repos.listEnabled()
-    if not repos:
-        raise RuntimeError("No enabled repos, canceling build.")
-
     # Create the final kickstart with repos and package list
     ks_path = joinpaths(results_dir, "final-kickstart.ks")
     with open(ks_path, "w") as f: