flaxo/ghost

public

Source code of Ghost - On Ghost

Add repository settings, and make deletion purge everything145628017 days ago157 lines · 5.2 KB

1	import { Injectable, Logger } from '@nestjs/common';
2	import { readFile, writeFile
3	import path from 'node:path
4
5	import { runGit }
6	import { WalStoreService }
7	import { emptyIndex, type
8
9	const SEQ_MARKER = '
10	const DEFAULT_BRANCH_PREFERENCE = [
11
12	/**
13	* Brings a cached bare repository up to the state the log describes.
14	*
15	* The cache is only ever behind the log, never ahead of it, so replay is always forward-only: apply the packfiles of every layer past the cached sequence, then reconcile refs to the index snapshot.
16	*/
17	@Injectable()
18	export class RepositoryMaterializerService
19	private readonly logger
20	private readonly inFlight
21
22	constructor(private readonly
23
24	async materialize(
25	repoId: string,
26	repoDirectory: string,
27	defaultBranch: string
28	): Promise<WalIndex
29	const pending =
30	if (pending) return
31
32	const run =
33	this.inFlight.delete
34	);
35	this.inFlight.set
36	return run;
37	}
38
39	/** Resolves once a replay in flight has finished, whatever its outcome, so its writes cannot land after the cache is removed. */
40	async settle(repoId
41	await this.inFlight
42	}
43
44	private async replay
45	repoId: string,
46	repoDirectory: string,
47	defaultBranch: string
48	): Promise<WalIndex
49	const stored =
50	if (!stored)
51
52	const { index
53	const cachedSeq =
54	// The default branch changes without a push, so HEAD is checked even when the cache is current.
55	if (cachedSeq >=
56	await this.ensureHead
57	return index;
58	}
59
60	for (const [offset
61	const seq =
62	if (seq <=
63
64	// Packs from receive-pack are thin: deltas may reference objects from earlier layers, which is why replay must stay in sequence order.
65	if (layer.size
66	await runGit({
67	args: ['index-pack',
68	gitDir: repoDirectory,
69	input: await this
70	});
71	}
72	}
73
74	await this.reconcileRefs
75	await this.ensureHead
76	await this.writeCachedSeq
77	this.logger.log
78	`Materialized ${repoId} from seq ${
79	);
80
81	return index;
82	}
83
84	private async reconcileRefs
85	const existing =
86	const commands:
87
88	for (const [ref
89	commands.push(`update
90	}
91	for (const ref
92	if (!index.refs
93	}
94
95	if (commands.length
96	await runGit({
97	args: ['update-ref',
98	gitDir: repoDirectory,
99	input: Buffer.from
100	});
101	}
102	}
103
104	private async listRefs
105	const output =
106	args: ['for-each-ref',
107	gitDir: repoDirectory,
108	});
109	return output.split
110	}
111
112	/** HEAD follows the chosen default branch while it exists. Otherwise a HEAD naming a missing branch clones as empty, so it is pointed at a branch that actually exists. */
113	private async ensureHead
114	repoDirectory: string,
115	index: WalIndex
116	defaultBranch: string
117	) {
118	if (index.refs
119
120	const current =
121	await runGit({
122	args: ['symbolic-ref',
123	gitDir: repoDirectory,
124	}).catch(()
125	).trim();
126
127	const chosen =
128	const target =
129	[chosen, current,
130	(ref) =>
131	) ?? [...index
132	if (!target \|\|
133
134	await runGit({
135	args: ['symbolic-ref',
136	gitDir: repoDirectory,
137	});
138	}
139
140	private seqMarkerPath(repoDirectory
141	return path.join
142	}
143
144	private async readCachedSeq
145	try {
146	const raw =
147	const seq =
148	return Number.isInteger
149	} catch {
150	return 0;
151	}
152	}
153
154	private async writeCachedSeq
155	await writeFile(this
156	}
157	}