_V*@sddlmZddlZddlmZddlmZddlmZddl m Z ddl m Z dd l mZmZd Ze eGd d d eZe Gd ddeZdS))unicode_literalsN)deque)total_ordering) ProjectState) OrderedSet)python_2_unicode_compatible)CircularDependencyErrorNodeNotFoundErroraMaximum recursion depth exceeded while generating migration graph, falling back to iterative approach. If you're experiencing performance issues, consider squashing migrations as described at https://docs.djangoproject.com/en/dev/topics/migrations/#squashing-migrations.c@seZdZdZddZddZddZdd Zd d Zd d Z ddZ ddZ ddZ ddZ ddZdS)Nodezp A single node in the migration graph. Contains direct links to adjacent nodes in either direction. cCs%||_t|_t|_dS)N)keysetchildrenparents)selfr r)r )rrrr__repr__0sz Node.__repr__cCs|jj|dS)N)radd)rchildrrr add_child3szNode.add_childcCs|jj|dS)N)rr)rparentrrr add_parent6szNode.add_parentcCs{d|jkrpt|jg}x0t|jD]}|jt|jq1Wtt ||jdMigration %s dependencies reference nonexistent parent node %r)r2r r1r"r r4)r migrationrr!rrradd_dependencyus    zMigrationGraph.add_dependencycCsa|jr]xE|jD]:}|j|jjdd|j|jjddqWd|_ndS)Nr#r*F)r3r2r1r$pop)rr6rrrr4s  zMigrationGraph.clear_cachec s|jkr(td|f|nj|fddd_j|}y|jSWn/tk rtjt t j |SYnXdS)z Given a node, returns a list of which previous nodes (dependencies) must be applied, ending with the node itself. This is the list you would follow if applying the migrations to a database. zNode %r not a valid nodecsddj|jDS)Ncss|]}|jVqdS)N)r ).0r!rrr szAMigrationGraph.forwards_plan....)r1r)x)rrrsz.MigrationGraph.forwards_plan..TN) r2r ensure_not_cyclicr3r1r( RuntimeErrorwarningswarnRECURSION_DEPTH_WARNINGRuntimeWarning iterative_dfs)rtargetr6r)rr forwards_plans   zMigrationGraph.forwards_planc s|jkr(td|f|nj|fddd_j|}y|jSWn5tk rtjt t j |ddSYnXdS)z Given a node, returns a list of which dependent nodes (dependencies) must be unapplied, ending with the node itself. This is the list you would follow if removing the migrations from a database. zNode %r not a valid nodecsddj|jDS)Ncss|]}|jVqdS)N)r )r;rrrrr<szBMigrationGraph.backwards_plan....)r1r)r=)rrrr>sz/MigrationGraph.backwards_plan..TforwardsFN) r2r r?r3r1r+r@rArBrCrDrE)rrFr6r)rrbackwards_plans   zMigrationGraph.backwards_planTcCst}|j||r4tt|j}ntt|j}xc|r|j}|j||rt|jdd}nt|jdd}|j|qLWtt |S)zI Iterative depth first search, for finding dependencies. reverseT) rappendr%rrpopleft appendleftr&r)r)rstartrHvisitedstackr6rrrrrEs     zMigrationGraph.iterative_dfsNcsxt}xb|jD]Wtfdd|jjD r| sZ|dkr|jqqWt|S)z Returns all root nodes - that is, nodes with no dependencies inside their app. These are the starting point for an app. c3s#|]}|ddkVqdS)rNr)r;r )r6rrr<sz,MigrationGraph.root_nodes..r)r r2anyr1rrr%)rapprootsr)r6r root_nodess  *zMigrationGraph.root_nodescsxt}xb|jD]Wtfdd|jjD r| sZ|dkr|jqqWt|S)an Returns all leaf nodes - that is, nodes with no dependents in their app. These are the "most current" version of an app's schema. Having more than one per app is technically an error, but one that gets handled further up, in the interactive command - it's usually the result of a VCS merge and needs some user input. c3s#|]}|ddkVqdS)rNr)r;r )r6rrr<sz,MigrationGraph.leaf_nodes..r)r r2rQr1rrr%)rrRZleavesr)r6r leaf_nodess  *zMigrationGraph.leaf_nodescCst|j}x|r|j}|g}x|r|d}x||D]z}||kr||j|d}tdjdd|Dn||krM|j||j|PqMqMW|j}q0WqWdS)Nrz, css|]}d|VqdS)z%s.%sNr)r;nrrrr<sz3MigrationGraph.ensure_not_cyclic..)r r2r:indexr joinrKremove)rrNZ get_childrentodor6rPtopcyclerrrr?s      %   z MigrationGraph.ensure_not_cycliccCsd|jS)NzGraph: %s nodes, %s edges)_nodes_and_edges)rrrrrszMigrationGraph.__str__cCs)|j\}}d|jj||fS)Nz<%s: nodes=%s, edges=%s>)r^ __class__r,)rr2edgesrrrrszMigrationGraph.__repr__cCs/t|jtdd|jjDfS)Ncss|]}t|jVqdS)N)lenr)r;r6rrrr<sz2MigrationGraph._nodes_and_edges..)rar2sumr1values)rrrrr^szMigrationGraph._nodes_and_edgescCs|dkr!t|j}nt|dkr:tSt|dtsY|g}ng}x]|D]U}xL|j|D];}||kr|| r||krq|n|j|q|q|WqfWtd|}x*|D]"}|j|j |dd}qW|S)z Given a migration node or nodes, returns a complete ProjectState for it. If at_end is False, returns the state before the migration has run. If nodes is not provided, returns the overall most current project state. Nr real_appsZpreserveF) r)rUrar isinstancetuplerGrKr2Z mutate_state)rr2at_endrdZplanr6r8Z project_staterrr make_states"      zMigrationGraph.make_statecCs ||jkS)N)r2)rr6rrr __contains__szMigrationGraph.__contains__)r,r-r.r/rr7r9r4rGrIrErTrUr?rrr^rhrirrrrr0Rs            r0) __future__rrA collectionsr functoolsrZdjango.db.migrations.staterZdjango.utils.datastructuresrZdjango.utils.encodingr exceptionsr r rCobjectr r0rrrrs ;