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1 | | -import neo4j from 'neo4j-driver' |
2 | 1 | import net from 'net' |
3 | 2 | import readline from 'readline' |
4 | 3 | import Context from './context.js' |
5 | | -import ResultObserver from './result-observer.js' |
6 | | -import { nativeToCypher, cypherToNative } from './cypher-native-binders.js' |
| 4 | +import * as requestHandlers from './request-handlers.js' |
7 | 5 |
|
8 | 6 | class Backend { |
9 | 7 | constructor ({ writer }) { |
@@ -50,234 +48,19 @@ class Backend { |
50 | 48 | request = JSON.parse(request) |
51 | 49 | const { name, data } = request |
52 | 50 | console.log('> Got request ' + name, data) |
53 | | - switch (name) { |
54 | | - case 'NewDriver': |
55 | | - { |
56 | | - const { |
57 | | - uri, |
58 | | - authorizationToken: { data: authToken }, |
59 | | - userAgent |
60 | | - } = data |
61 | | - const driver = neo4j.driver(uri, authToken, { userAgent }) |
62 | | - const id = this._context.addDriver(driver) |
63 | | - this._writeResponse('Driver', { id }) |
64 | | - } |
65 | | - break |
66 | | - |
67 | | - case 'DriverClose': |
68 | | - { |
69 | | - const { driverId } = data |
70 | | - const driver = this._context.getDriver(driverId) |
71 | | - driver |
72 | | - .close() |
73 | | - .then(() => { |
74 | | - this._writeResponse('Driver', { id: driverId }) |
75 | | - }) |
76 | | - .catch(err => this._writeError(err)) |
77 | | - this._context.removeDriver(driverId) |
78 | | - } |
79 | | - break |
80 | | - |
81 | | - case 'NewSession': |
82 | | - { |
83 | | - let { driverId, accessMode, bookmarks, database, fetchSize } = data |
84 | | - switch (accessMode) { |
85 | | - case 'r': |
86 | | - accessMode = neo4j.session.READ |
87 | | - break |
88 | | - case 'w': |
89 | | - accessMode = neo4j.session.WRITE |
90 | | - break |
91 | | - default: |
92 | | - this._writeBackendError('Unknown accessmode: ' + accessMode) |
93 | | - return |
94 | | - } |
95 | | - const driver = this._context.getDriver(driverId) |
96 | | - const session = driver.session({ |
97 | | - defaultAccessMode: accessMode, |
98 | | - bookmarks, |
99 | | - database, |
100 | | - fetchSize |
101 | | - }) |
102 | | - const id = this._context.addSession(session) |
103 | | - this._writeResponse('Session', { id }) |
104 | | - } |
105 | | - break |
106 | | - |
107 | | - case 'SessionClose': |
108 | | - { |
109 | | - const { sessionId } = data |
110 | | - const session = this._context.getSession(sessionId) |
111 | | - session |
112 | | - .close() |
113 | | - .then(() => { |
114 | | - this._writeResponse('Session', { id: sessionId }) |
115 | | - }) |
116 | | - .catch(err => this._writeError(err)) |
117 | | - this._context.removeSession(sessionId) |
118 | | - } |
119 | | - break |
120 | | - |
121 | | - case 'SessionRun': |
122 | | - { |
123 | | - const { sessionId, cypher, params, txMeta: metadata, timeout } = data |
124 | | - const session = this._context.getSession(sessionId) |
125 | | - if (params) { |
126 | | - for (const [key, value] of Object.entries(params)) { |
127 | | - params[key] = cypherToNative(value) |
128 | | - } |
129 | | - } |
130 | 51 |
|
131 | | - const observers = this._context.getResultObserversBySessionId( |
132 | | - sessionId |
133 | | - ) |
134 | | - |
135 | | - Promise.all(observers.map(obs => obs.completitionPromise())) |
136 | | - .catch(_ => null) |
137 | | - .then(_ => { |
138 | | - const result = session.run(cypher, params, { metadata, timeout }) |
139 | | - const resultObserver = new ResultObserver({ sessionId }) |
140 | | - result.subscribe(resultObserver) |
141 | | - const id = this._context.addResultObserver(resultObserver) |
142 | | - this._writeResponse('Result', { id }) |
143 | | - }) |
144 | | - } |
145 | | - break |
146 | | - |
147 | | - case 'ResultNext': |
148 | | - { |
149 | | - const { resultId } = data |
150 | | - const resultObserver = this._context.getResultObserver(resultId) |
151 | | - const nextPromise = resultObserver.next() |
152 | | - nextPromise |
153 | | - .then(rec => { |
154 | | - if (rec) { |
155 | | - const values = Array.from(rec.values()).map(nativeToCypher) |
156 | | - this._writeResponse('Record', { |
157 | | - values: values |
158 | | - }) |
159 | | - } else { |
160 | | - this._writeResponse('NullRecord', null) |
161 | | - } |
162 | | - }) |
163 | | - .catch(e => { |
164 | | - console.log('got some err: ' + JSON.stringify(e)) |
165 | | - this._writeError(e) |
166 | | - }) |
167 | | - } |
168 | | - break |
169 | | - |
170 | | - case 'SessionReadTransaction': |
171 | | - { |
172 | | - const { sessionId } = data |
173 | | - const session = this._context.getSession(sessionId) |
174 | | - session |
175 | | - .readTransaction( |
176 | | - tx => |
177 | | - new Promise((resolve, reject) => { |
178 | | - const id = this._context.addTx(tx, sessionId, resolve, reject) |
179 | | - this._writeResponse('RetryableTry', { id }) |
180 | | - }) |
181 | | - ) |
182 | | - .then(_ => this._writeResponse('RetryableDone', null)) |
183 | | - .catch(error => this._writeError(error)) |
184 | | - } |
185 | | - break |
186 | | - |
187 | | - case 'TransactionRun': |
188 | | - { |
189 | | - const { txId, cypher, params } = data |
190 | | - const tx = this._context.getTx(txId) |
191 | | - if (params) { |
192 | | - for (const [key, value] of Object.entries(params)) { |
193 | | - params[key] = cypherToNative(value) |
194 | | - } |
195 | | - } |
196 | | - const result = tx.tx.run(cypher, params) |
197 | | - const resultObserver = new ResultObserver({}) |
198 | | - result.subscribe(resultObserver) |
199 | | - const id = this._context.addResultObserver(resultObserver) |
200 | | - this._writeResponse('Result', { id }) |
201 | | - } |
202 | | - break |
203 | | - |
204 | | - case 'RetryablePositive': |
205 | | - { |
206 | | - const { sessionId } = data |
207 | | - this._context.getTxsBySessionId(sessionId).forEach(tx => { |
208 | | - tx.resolve() |
209 | | - this._context.removeTx(tx.id) |
210 | | - }) |
211 | | - } |
212 | | - break |
213 | | - |
214 | | - case 'RetryableNegative': |
215 | | - { |
216 | | - const { sessionId, errorId } = data |
217 | | - const error = |
218 | | - this._context.getError(errorId) || new Error('Client error') |
219 | | - this._context.getTxsBySessionId(sessionId).forEach(tx => { |
220 | | - tx.reject(error) |
221 | | - this._context.removeTx(tx.id) |
222 | | - }) |
223 | | - } |
224 | | - break |
225 | | - |
226 | | - case 'SessionBeginTransaction': |
227 | | - { |
228 | | - const { sessionId, txMeta: metadata, timeout } = data |
229 | | - const session = this._context.getSession(sessionId) |
230 | | - const tx = session.beginTransaction({ metadata, timeout }) |
231 | | - const id = this._context.addTx(tx, sessionId) |
232 | | - this._writeResponse('Transaction', { id }) |
233 | | - } |
234 | | - break |
235 | | - |
236 | | - case 'TransactionCommit': |
237 | | - { |
238 | | - const { txId: id } = data |
239 | | - const { tx } = this._context.getTx(id) |
240 | | - tx.commit() |
241 | | - .then(() => this._writeResponse('Transaction', { id })) |
242 | | - .catch(e => { |
243 | | - console.log('got some err: ' + JSON.stringify(e)) |
244 | | - this._writeError(e) |
245 | | - }) |
246 | | - this._context.removeTx(id) |
247 | | - } |
248 | | - break |
249 | | - |
250 | | - case 'SessionLastBookmarks': |
251 | | - { |
252 | | - const { sessionId } = data |
253 | | - const session = this._context.getSession(sessionId) |
254 | | - const bookmarks = session.lastBookmark() |
255 | | - this._writeResponse('Bookmarks', { bookmarks }) |
256 | | - } |
257 | | - break |
258 | | - |
259 | | - case 'SessionWriteTransaction': |
260 | | - { |
261 | | - const { sessionId } = data |
262 | | - const session = this._context.getSession(sessionId) |
263 | | - session |
264 | | - .writeTransaction( |
265 | | - tx => |
266 | | - new Promise((resolve, reject) => { |
267 | | - const id = this._context.addTx(tx, sessionId, resolve, reject) |
268 | | - this._writeResponse('RetryableTry', { id }) |
269 | | - }) |
270 | | - ) |
271 | | - .then(_ => this._writeResponse('RetryableDone', null)) |
272 | | - .catch(error => this._writeError(error)) |
273 | | - } |
274 | | - break |
275 | | - |
276 | | - default: |
277 | | - this._writeBackendError('Unknown request: ' + name) |
278 | | - console.log('Unknown request: ' + name) |
279 | | - console.log(JSON.stringify(data)) |
| 52 | + if (name in requestHandlers) { |
| 53 | + requestHandlers[name](this._context, data, { |
| 54 | + writeResponse: this._writeResponse.bind(this), |
| 55 | + writeError: this._writeError.bind(this), |
| 56 | + writeBackendError: this._writeBackendError.bind(this) |
| 57 | + }) |
| 58 | + return |
280 | 59 | } |
| 60 | + |
| 61 | + this._writeBackendError('Unknown request: ' + name) |
| 62 | + console.log('Unknown request: ' + name) |
| 63 | + console.log(JSON.stringify(data)) |
281 | 64 | } |
282 | 65 |
|
283 | 66 | _writeResponse (name, data) { |
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