${devcontainerId} (devcontainers/spec#62)

src/spec-common/variableSubstitution.ts

@@ -4,6 +4,7 @@
  *--------------------------------------------------------------------------------------------*/
 
 import * as path from 'path';
+import * as crypto from 'crypto';
 
 import { ContainerError } from './errors';
 import { URI } from 'vscode-uri';
@@ -32,6 +33,11 @@ export function substitute<T extends object>(context: SubstitutionContext, value
 	return substitute0(replace, value);
 }
 
+export function beforeContainerSubstitute<T extends object>(idLabels: Record<string, string>, value: T): T {
+	let devcontainerId: string | undefined;
+	return substitute0(replaceDevContainerId.bind(undefined, () => devcontainerId || (devcontainerId = devcontainerIdForLabels(idLabels))), value);
+}
+
 export function containerSubstitute<T extends object>(platform: NodeJS.Platform, configFile: URI | undefined, containerEnv: NodeJS.ProcessEnv, value: T): T {
 	const isWindows = platform === 'win32';
 	return substitute0(replaceContainerEnv.bind(undefined, isWindows, configFile, normalizeEnv(isWindows, containerEnv)), value);
@@ -44,7 +50,7 @@ function substitute0(replace: Replace, value: any): any {
 		return resolveString(replace, value);
 	} else if (Array.isArray(value)) {
 		return value.map(s => substitute0(replace, s));
-	} else if (value && typeof value === 'object') {
+	} else if (value && typeof value === 'object' && !URI.isUri(value)) {
 		const result: any = Object.create(null);
 		Object.keys(value).forEach(key => {
 			result[key] = substitute0(replace, value[key]);
@@ -118,6 +124,16 @@ function replaceContainerEnv(isWindows: boolean, configFile: URI | undefined, co
 	}
 }
 
+function replaceDevContainerId(getDevContainerId: () => string, match: string, variable: string) {
+	switch (variable) {
+		case 'devcontainerId':
+			return getDevContainerId();
+
+		default:
+			return match;
+	}
+}
+
 function lookupValue(isWindows: boolean, envObj: NodeJS.ProcessEnv, args: string[], match: string, configFile: URI | undefined) {
 	if (args.length > 0) {
 		let envVariableName = args[0];
@@ -141,3 +157,15 @@ function lookupValue(isWindows: boolean, envObj: NodeJS.ProcessEnv, args: string
 		description: `'${match}'${configFile ? ` in ${path.posix.basename(configFile.path)}` : ''} can not be resolved because no environment variable name is given.`
 	});
 }
+
+function devcontainerIdForLabels(idLabels: Record<string, string>): string {
+	const stringInput = JSON.stringify(idLabels, Object.keys(idLabels).sort()); // sort properties
+	const bufferInput = Buffer.from(stringInput, 'utf-8');
+	const hash = crypto.createHash('sha256')
+		.update(bufferInput)
+		.digest();
+	const uniqueId = BigInt(`0x${hash.toString('hex')}`)
+		.toString(32)
+		.padStart(52, '0');
+	return uniqueId;
+}

src/spec-node/configContainer.ts

@@ -9,8 +9,8 @@ import * as jsonc from 'jsonc-parser';
 
 import { openDockerfileDevContainer } from './singleContainer';
 import { openDockerComposeDevContainer } from './dockerCompose';
-import { ResolverResult, DockerResolverParameters, isDockerFileConfig, runUserCommand, createDocuments, getWorkspaceConfiguration, BindMountConsistency, uriToFsPath, DevContainerAuthority, isDevContainerAuthority, SubstituteConfig, SubstitutedConfig } from './utils';
-import { substitute } from '../spec-common/variableSubstitution';
+import { ResolverResult, DockerResolverParameters, isDockerFileConfig, runUserCommand, createDocuments, getWorkspaceConfiguration, BindMountConsistency, uriToFsPath, DevContainerAuthority, isDevContainerAuthority, SubstituteConfig, SubstitutedConfig, addSubstitution, envListToObj } from './utils';
+import { beforeContainerSubstitute, substitute } from '../spec-common/variableSubstitution';
 import { ContainerError } from '../spec-common/errors';
 import { Workspace, workspaceFromPath, isWorkspacePath } from '../spec-utils/workspaces';
 import { URI } from 'vscode-uri';
@@ -52,7 +52,7 @@ async function resolveWithLocalFolder(params: DockerResolverParameters, parsedAu
 			throw new ContainerError({ description: `No dev container config and no workspace found.` });
 		}
 	}
-	const configWithRaw = configs.config;
+	const configWithRaw = addSubstitution(configs.config, config => beforeContainerSubstitute(envListToObj(idLabels), config));
 	const { config } = configWithRaw;
 
 	await runUserCommand({ ...params, common: { ...common, output: common.postCreate.output } }, config.initializeCommand, common.postCreate.onDidInput);

src/spec-node/devContainersSpecCLI.ts

@@ -9,7 +9,7 @@ import yargs, { Argv } from 'yargs';
 import * as jsonc from 'jsonc-parser';
 
 import { createDockerParams, createLog, experimentalImageMetadataDefault, launch, ProvisionOptions } from './devContainers';
-import { SubstitutedConfig, createContainerProperties, createFeaturesTempFolder, envListToObj, inspectDockerImage, isDockerFileConfig, SubstituteConfig } from './utils';
+import { SubstitutedConfig, createContainerProperties, createFeaturesTempFolder, envListToObj, inspectDockerImage, isDockerFileConfig, SubstituteConfig, addSubstitution } from './utils';
 import { URI } from 'vscode-uri';
 import { ContainerError } from '../spec-common/errors';
 import { Log, LogLevel, makeLog, mapLogLevel } from '../spec-utils/log';
@@ -30,7 +30,7 @@ import { featuresTestOptions, featuresTestHandler } from './featuresCLI/test';
 import { featuresPackageHandler, featuresPackageOptions } from './featuresCLI/package';
 import { featuresPublishHandler, featuresPublishOptions } from './featuresCLI/publish';
 import { featuresInfoHandler, featuresInfoOptions } from './featuresCLI/info';
-import { containerSubstitute } from '../spec-common/variableSubstitution';
+import { beforeContainerSubstitute, containerSubstitute } from '../spec-common/variableSubstitution';
 import { getPackageConfig, PackageConfiguration } from '../spec-utils/product';
 import { getDevcontainerMetadata, getImageBuildInfo, getImageMetadataFromContainer, ImageMetadataEntry, mergeConfiguration, MergedDevContainerConfig } from './imageMetadata';
 import { templatesPublishHandler, templatesPublishOptions } from './templatesCLI/publish';
@@ -214,7 +214,7 @@ async function provision({
 			};
 		}) : [],
 		updateRemoteUserUIDDefault,
-		remoteEnv: keyValuesToRecord(addRemoteEnvs),
+		remoteEnv: envListToObj(addRemoteEnvs),
 		additionalCacheFroms: addCacheFroms,
 		useBuildKit: buildkit,
 		buildxPlatform: undefined,
@@ -597,7 +597,7 @@ async function doRunUserCommands({
 			persistedFolder,
 			additionalMounts: [],
 			updateRemoteUserUIDDefault: 'never',
-			remoteEnv: keyValuesToRecord(addRemoteEnvs),
+			remoteEnv: envListToObj(addRemoteEnvs),
 			additionalCacheFroms: [],
 			useBuildKit: 'auto',
 			buildxPlatform: undefined,
@@ -759,13 +759,8 @@ async function readConfiguration({
 		};
 		const container = containerId ? await inspectContainer(params, containerId) : await findDevContainer(params, idLabels);
 		if (container) {
-			const substitute1 = configuration.substitute;
-			const substitute2: SubstituteConfig = config => containerSubstitute(cliHost.platform, configuration.config.configFilePath, envListToObj(container.Config.Env), config);
-			configuration = {
-				config: substitute2(configuration.config),
-				raw: configuration.raw,
-				substitute: config => substitute2(substitute1(config)),
-			};
+			configuration = addSubstitution(configuration, config => beforeContainerSubstitute(envListToObj(idLabels), config));
+			configuration = addSubstitution(configuration, config => containerSubstitute(cliHost.platform, configuration.config.configFilePath, envListToObj(container.Config.Env), config));
 		}
 
 		const additionalFeatures = additionalFeaturesJson ? jsonc.parse(additionalFeaturesJson) as Record<string, string | boolean | Record<string, string | boolean>> : {};
@@ -927,7 +922,7 @@ export async function doExec({
 			persistedFolder,
 			additionalMounts: [],
 			updateRemoteUserUIDDefault: 'never',
-			remoteEnv: keyValuesToRecord(addRemoteEnvs),
+			remoteEnv: envListToObj(addRemoteEnvs),
 			additionalCacheFroms: [],
 			useBuildKit: 'auto',
 			omitLoggerHeader: true,
@@ -989,16 +984,6 @@ export async function doExec({
 	}
 }
 
-function keyValuesToRecord(keyValues: string[]): Record<string, string> {
-	return keyValues.reduce((envs, env) => {
-		const i = env.indexOf('=');
-		if (i !== -1) {
-			envs[env.substring(0, i)] = env.substring(i + 1);
-		}
-		return envs;
-	}, {} as Record<string, string>);
-}
-
 function getDefaultIdLabels(workspaceFolder: string) {
 	return [`${hostFolderLabel}=${workspaceFolder}`];
 }

src/spec-node/utils.ts

@@ -120,6 +120,15 @@ export interface SubstitutedConfig<T> {
 
 export type SubstituteConfig = <U extends DevContainerConfig | ImageMetadataEntry>(value: U) => U;
 
+export function addSubstitution<T>(config: SubstitutedConfig<T>, substitute: SubstituteConfig): SubstitutedConfig<T> {
+	const substitute0 = config.substitute;
+	return {
+		config: substitute(config.config),
+		raw: config.raw,
+		substitute: value => substitute(substitute0(value)),
+	};
+}
+
 export async function startEventSeen(params: DockerResolverParameters, labels: Record<string, string>, canceled: Promise<void>, output: Log, trace: boolean) {
 	const eventsProcess = await getEvents(params, { event: ['start'] });
 	return {
@@ -350,10 +359,10 @@ export function envListToObj(list: string[] | null) {
 	return (list || []).reduce((obj, pair) => {
 		const i = pair.indexOf('=');
 		if (i !== -1) {
-			obj[pair.substr(0, i)] = pair.substr(i + 1);
+			obj[pair.substring(0, i)] = pair.substring(i + 1);
 		}
 		return obj;
-	}, {} as NodeJS.ProcessEnv);
+	}, {} as Record<string, string>);
 }
 
 export async function runUserCommand(params: DockerResolverParameters, command: string | string[] | undefined, onDidInput?: Event<string>) {

src/test/variableSubstitution.test.ts

@@ -4,7 +4,7 @@
 
 import * as assert from 'assert';
 
-import { containerSubstitute, substitute } from '../spec-common/variableSubstitution';
+import { beforeContainerSubstitute, containerSubstitute, substitute } from '../spec-common/variableSubstitution';
 import { URI } from 'vscode-uri';
 
 describe('Variable substitution', function () {
@@ -141,4 +141,30 @@ describe('Variable substitution', function () {
 		const result = containerSubstitute('linux', URI.file('/foo/bar/baz.json'), {}, raw);
 		assert.strictEqual(result.foo, 'bardefaultbar');
 	});
+
+	it(`replaces devcontainerId`, async () => {
+		const raw = {
+			test: '${devcontainerId}'
+		};
+		const result = beforeContainerSubstitute({ a: 'b' }, raw);
+		assert.ok(/^[0-9a-v]{52}$/.test(result.test), `Got: ${result.test}`);
+	});
+
+	it(`replaces devcontainerId and additional id labels matter`, async () => {
+		const raw = {
+			test: '${devcontainerId}'
+		};
+		const result1 = beforeContainerSubstitute({ a: 'b' }, raw);
+		const result2 = beforeContainerSubstitute({ a: 'b', c: 'd' }, raw);
+		assert.notStrictEqual(result1.test, result2.test);
+	});
+
+	it(`replaces devcontainerId and label order does not matter`, async () => {
+		const raw = {
+			test: '${devcontainerId}'
+		};
+		const result1 = beforeContainerSubstitute({ c: 'd', a: 'b' }, raw);
+		const result2 = beforeContainerSubstitute({ a: 'b', c: 'd' }, raw);
+		assert.strictEqual(result1.test, result2.test);
+	});
 });