|
| 1 | +import {json} from "micro"; |
| 2 | +import JSONStream from "JSONStream"; |
| 3 | +import {Transform} from "stream"; |
| 4 | + |
| 5 | +import {badRequest, failedCheck} from "./errors.js"; |
| 6 | +import {validateQueryPayload} from "./validate.js"; |
| 7 | + |
| 8 | +const READ_ONLY = new Set(["SELECT", "USAGE", "CONNECT"]); |
| 9 | + |
| 10 | +export class OracleSingleton { |
| 11 | + static instance = null; |
| 12 | + constructor() { |
| 13 | + throw new Error( |
| 14 | + "Do not use new OracleSingleton(). Call OracleSingleton.initialize() instead." |
| 15 | + ); |
| 16 | + } |
| 17 | + static initialize() { |
| 18 | + if (!OracleSingleton.instance) { |
| 19 | + try { |
| 20 | + OracleSingleton.instance = import("oracledb").then((module) => { |
| 21 | + const oracledb = module.default; |
| 22 | + oracledb.initOracleClient({ |
| 23 | + libDir: process.env.LIB_DIR_PATH, |
| 24 | + }); |
| 25 | + return oracledb; |
| 26 | + }); |
| 27 | + } catch (err) { |
| 28 | + console.error(err); |
| 29 | + } |
| 30 | + } |
| 31 | + } |
| 32 | + static getInstance() { |
| 33 | + if (!OracleSingleton.instance) |
| 34 | + throw new Error( |
| 35 | + "OracleSingleton not initialized. Call OracleSingleton.initialize() first." |
| 36 | + ); |
| 37 | + return OracleSingleton.instance; |
| 38 | + } |
| 39 | +} |
| 40 | + |
| 41 | +export async function queryStream(req, res, pool) { |
| 42 | + const db = await pool; |
| 43 | + const connection = await db.getConnection(); |
| 44 | + const body = await json(req); |
| 45 | + |
| 46 | + if (!validateQueryPayload(body)) throw badRequest(); |
| 47 | + |
| 48 | + res.setHeader("Content-Type", "text/plain"); |
| 49 | + const keepAlive = setInterval(() => res.write("\n"), 25e3); |
| 50 | + |
| 51 | + let {sql, params = []} = body; |
| 52 | + |
| 53 | + try { |
| 54 | + await new Promise((resolve, reject) => { |
| 55 | + const columnNameMap = new Map(); |
| 56 | + const stream = connection.queryStream(sql, params, { |
| 57 | + extendedMetaData: true, |
| 58 | + }); |
| 59 | + |
| 60 | + stream |
| 61 | + .on("error", function (e) { |
| 62 | + this.destroy(); |
| 63 | + reject(e); |
| 64 | + }) |
| 65 | + .on("metadata", (columns) => { |
| 66 | + clearInterval(keepAlive); |
| 67 | + |
| 68 | + const schema = { |
| 69 | + type: "array", |
| 70 | + items: { |
| 71 | + type: "object", |
| 72 | + properties: columns.reduce((schema, {dbType, name}, idx) => { |
| 73 | + columnNameMap.set(idx, name); |
| 74 | + return { |
| 75 | + ...schema, |
| 76 | + ...{[name]: dataTypeSchema({type: dbType})}, |
| 77 | + }; |
| 78 | + }, {}), |
| 79 | + }, |
| 80 | + }; |
| 81 | + res.write(`${JSON.stringify(schema)}`); |
| 82 | + res.write("\n"); |
| 83 | + }) |
| 84 | + .on("end", function () { |
| 85 | + this.destroy(); |
| 86 | + }) |
| 87 | + .on("close", resolve) |
| 88 | + .pipe( |
| 89 | + new Transform({ |
| 90 | + objectMode: true, |
| 91 | + transform(chunk, encoding, cb) { |
| 92 | + let row = null; |
| 93 | + try { |
| 94 | + row = chunk.reduce((acc, r, idx) => { |
| 95 | + const key = columnNameMap.get(idx); |
| 96 | + return {...acc, [key]: r}; |
| 97 | + }, {}); |
| 98 | + } catch (e) { |
| 99 | + console.error("row has unexpected format"); |
| 100 | + // TODO: Add error handling once server supports handling error for in flight streamed response |
| 101 | + // cb(new Error(e)); |
| 102 | + } |
| 103 | + cb(null, row); |
| 104 | + }, |
| 105 | + }) |
| 106 | + ) |
| 107 | + .pipe(JSONStream.stringify("", "\n", "\n")) |
| 108 | + .pipe(res); |
| 109 | + }); |
| 110 | + } catch (error) { |
| 111 | + if (!error.statusCode) error.statusCode = 400; |
| 112 | + throw error; |
| 113 | + } finally { |
| 114 | + clearInterval(keepAlive); |
| 115 | + if (connection) { |
| 116 | + try { |
| 117 | + await connection.close(); |
| 118 | + } catch (err) { |
| 119 | + console.error(err); |
| 120 | + } |
| 121 | + } |
| 122 | + } |
| 123 | + |
| 124 | + res.end(); |
| 125 | +} |
| 126 | + |
| 127 | +/* |
| 128 | + * This function is checking for the permission of the given credentials. It alerts the user setting |
| 129 | + * them up that these may be too permissive. |
| 130 | + * */ |
| 131 | +export async function check(req, res, pool) { |
| 132 | + let connection; |
| 133 | + try { |
| 134 | + const db = await pool; |
| 135 | + connection = await db.getConnection(); |
| 136 | + |
| 137 | + // see: https://docs.oracle.com/en/database/oracle/oracle-database/12.2/refrn/SESSION_PRIVS.html |
| 138 | + const {rows} = await connection.execute(`SELECT * FROM session_privs`); |
| 139 | + |
| 140 | + const permissive = rows |
| 141 | + .map(([permission]) => permission) |
| 142 | + .filter((g) => !READ_ONLY.has(g)); |
| 143 | + |
| 144 | + if (permissive.length) |
| 145 | + throw failedCheck( |
| 146 | + `User has too permissive grants: ${permissive.join(", ")}` |
| 147 | + ); |
| 148 | + |
| 149 | + return {ok: true}; |
| 150 | + } catch (e) { |
| 151 | + throw e; |
| 152 | + } finally { |
| 153 | + if (connection) { |
| 154 | + try { |
| 155 | + await connection.close(); |
| 156 | + } catch (err) { |
| 157 | + console.error(err.message); |
| 158 | + } |
| 159 | + } |
| 160 | + } |
| 161 | +} |
| 162 | + |
| 163 | +export default async ({url, username, password}) => { |
| 164 | + OracleSingleton.initialize(); |
| 165 | + // We do not want to import the oracledb library until we are sure that the user is looking to use Oracle. |
| 166 | + // Installing the oracledb library is a pain, so we want to avoid it if possible. |
| 167 | + const config = { |
| 168 | + username: username, |
| 169 | + password: password, |
| 170 | + connectionString: decodeURI(url), |
| 171 | + }; |
| 172 | + |
| 173 | + const oracledb = await OracleSingleton.getInstance(); |
| 174 | + const pool = oracledb.createPool(config); |
| 175 | + |
| 176 | + return async (req, res) => { |
| 177 | + return queryStream(req, res, pool); |
| 178 | + }; |
| 179 | +}; |
| 180 | + |
| 181 | +// See https://oracle.github.io/node-oracledb/doc/api.html#-312-oracle-database-type-constants |
| 182 | +const boolean = ["null", "boolean"], |
| 183 | + number = ["null", "number"], |
| 184 | + object = ["null", "object"], |
| 185 | + string = ["null", "string"]; |
| 186 | +export function dataTypeSchema({type}) { |
| 187 | + const oracledb = OracleSingleton.getInstance(); |
| 188 | + |
| 189 | + switch (type) { |
| 190 | + case oracledb.DB_TYPE_BOOLEAN: |
| 191 | + return {type: boolean}; |
| 192 | + case oracledb.DB_TYPE_NUMBER: |
| 193 | + case oracledb.DB_TYPE_BINARY_DOUBLE: |
| 194 | + case oracledb.DB_TYPE_BINARY_FLOAT: |
| 195 | + case oracledb.DB_TYPE_BINARY_INTEGER: |
| 196 | + return {type: number}; |
| 197 | + case oracledb.DB_TYPE_TIMESTAMP: |
| 198 | + case oracledb.DB_TYPE_DATE: |
| 199 | + case oracledb.DB_TYPE_TIMESTAMP_TZ: |
| 200 | + case oracledb.DB_TYPE_TIMESTAMP_LTZ: |
| 201 | + case oracledb.DB_TYPE_INTERVAL_DS: |
| 202 | + case oracledb.DB_TYPE_INTERVAL_YM: |
| 203 | + return {type: string, date: true}; |
| 204 | + case oracledb.DB_TYPE_BLOB: |
| 205 | + return {type: object, buffer: true}; |
| 206 | + case oracledb.DB_TYPE_CHAR: |
| 207 | + case oracledb.DB_TYPE_BFILE: |
| 208 | + case oracledb.DB_TYPE_CLOB: |
| 209 | + case oracledb.DB_TYPE_NCLOB: |
| 210 | + case oracledb.DB_TYPE_CURSOR: |
| 211 | + case oracledb.DB_TYPE_LONG_RAW: |
| 212 | + case oracledb.DB_TYPE_NCHAR: |
| 213 | + case oracledb.DB_TYPE_NVARCHAR: |
| 214 | + case oracledb.DB_TYPE_OBJECT: |
| 215 | + case oracledb.DB_TYPE_RAW: |
| 216 | + case oracledb.DB_TYPE_ROWID: |
| 217 | + case oracledb.DB_TYPE_VARCHAR: |
| 218 | + default: |
| 219 | + return {type: string}; |
| 220 | + } |
| 221 | +} |
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