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Loopback: Discover a schema in a db.
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| /* | |
| * Discovers a table schema and outputs it into a file: run this script via: | |
| * $ node discover-schema.js | |
| */ | |
| var path = require('path'); | |
| var fs = require('fs'); | |
| var app = require('loopback'); | |
| var output_directory = path.resolve(__dirname, '..', '..', 'common', 'models'); | |
| function callback(err, schema) { | |
| if (err) { | |
| console.error(err); | |
| return; | |
| } | |
| if (typeof schema != 'object') { | |
| throw 'schema object not defined'; | |
| } | |
| console.log("Auto discovery for schema " + schema.name); | |
| /* | |
| * Convert schema name from CamelCase to dashed lowercase (loopback format | |
| * for json files describing models), for example: CamelCase -> camel-case. | |
| */ | |
| //var model_name = schema.name.replace(/([a-z])([A-Z])/g, '$1-$2').toLowerCase(); | |
| var model_name = mapName(null, schema.name); | |
| console.log('Writing model JSON file..'); | |
| // write model definition JSON file | |
| var now_ms = Date.now(); | |
| var model_JSON_file = path.join(output_directory, model_name + '.json'); | |
| // if JSON file exists | |
| if (fs.existsSync(model_JSON_file)) { | |
| // save a backup copy of the JSON file | |
| let bkp_file = path.join(output_directory, model_name + ".json" + '.bkp_' + now_ms); | |
| fs.renameSync(model_JSON_file, bkp_file); | |
| console.log("Backing up old JSON file.."); | |
| } | |
| // write the new JSON file | |
| fs.writeFileSync( | |
| model_JSON_file, | |
| JSON.stringify(schema, null, 2) | |
| ); | |
| console.log("JSON saved to " + model_JSON_file); | |
| console.log('Writing model JS file..'); | |
| // write model JS file, useful to extend a model with custom methods | |
| var model_JS_file = path.join(output_directory, model_name + '.js'); | |
| // if JS file exists | |
| if (fs.existsSync(model_JS_file)) { | |
| // save a backup copy of the JS file | |
| let bkp_file = path.join(output_directory, model_name + ".js" + '.bkp_' + now_ms) | |
| fs.renameSync(model_JS_file, bkp_file); | |
| console.log("Backing up old JS file.."); | |
| } | |
| // write the new JS file | |
| fs.writeFileSync( | |
| model_JS_file, | |
| "'use strict';module.exports=function(" + model_name + ") {};" | |
| ); | |
| console.log("JSON saved to " + model_JSON_file); | |
| // Append model to model-config.json | |
| var model_config_file = path.resolve(__dirname, '../model-config.json'); | |
| var model_config_obj = JSON.parse(fs.readFileSync(model_config_file, 'utf8')); | |
| if (typeof model_config_obj[model_name] === 'undefined') { | |
| let datasource = process.argv[3]; | |
| model_config_obj[model_name] = { 'dataSource': datasource, 'public': false }; | |
| let json_content = JSON.stringify(model_config_obj, null, 2); | |
| fs.writeFileSync(model_config_file, JSON.stringify(model_config_obj, null, 2)); | |
| } | |
| } | |
| function printUsage() { | |
| console.log("\nUsage: node discover-schema.js [-ds datasource -sn db_schema_name]\n" + | |
| "\t-ds datasource: name of the datasource as specified in datasources.json\n" + | |
| "\t-tn db_table_name: name of the table in the db\n"); | |
| } | |
| // custom name mapper | |
| function mapName(type, name) { | |
| return name; | |
| }; | |
| function main() { | |
| switch (process.argv.length) { | |
| /* | |
| * if there are 6 params (first and second are execPath and JS file being executed) | |
| */ | |
| case 6: | |
| // should be datasource | |
| var param11 = process.argv[2]; | |
| var datasource = process.argv[3]; | |
| // should be db schema name | |
| var param21 = process.argv[4]; | |
| var table_name = process.argv[5]; | |
| var datasource_json = JSON.parse(fs.readFileSync(path.resolve(__dirname, '..', 'datasources.json'), 'utf8')); | |
| if (param11 === '-ds' && param21 === '-tn' && datasource_json.hasOwnProperty(datasource)) { | |
| options = {}; | |
| options.nameMapper = mapName; | |
| var ds = app.createDataSource(datasource, datasource_json[datasource]); | |
| ds.discoverSchema(table_name, options, callback); | |
| } else { | |
| printUsage(); | |
| } | |
| break; | |
| default: | |
| printUsage(); | |
| } | |
| } | |
| // main function | |
| main(); |
Thanks. But it seems like hasOwnProperty returns false everytime.
@honestserpent - thx dude. I think this is gonna do what I needed, but im getting
error: '[node-ibm_db] SQL_ERROR',
message: '[IBM][CLI Driver][DB2/LINUXX8664] SQL0206N "LIVE.TBLADDRESS" is not valid in the context where it is used. SQLSTATE=42703\r\n',
state: '42S22'
Where I'm connecting to a DB2 where "live" is the schema and "tbladdress" is the table name.
I have tried w/ and w/o the schema so "live.tbladdress" "tbladdress" and all caps, all lower "LIVE.TBLADDRESS" "TBLADDRESS" - no luck
Any Ideas?
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Thanks.
But, this is what i got : "
Usage: node discover-schema.js [-ds datasource -sn db_schema_name]
-ds datasource: name of the datasource as specified in datasources.json
-tn db_table_name: name of the table in the db"