HdfsFile
Hdfs file source connector
Description
Read data from hdfs file system.
Key features
Read all the data in a split in a pollNext call. What splits are read will be saved in snapshot.
- schema projection
- parallelism
- support user-defined split
- file format
- text
- csv
- parquet
- orc
- json
Options
| name | type | required | default value |
|---|---|---|---|
| path | string | yes | - |
| type | string | yes | - |
| fs.defaultFS | string | yes | - |
| schema | config | no | - |
path [string]
The source file path.
type [string]
File type, supported as the following file types:
text csv parquet orc json
If you assign file type to json, you should also assign schema option to tell connector how to parse data to the row you want.
For example:
upstream data is the following:
{"code": 200, "data": "get success", "success": true}
You can also save multiple pieces of data in one file and split them by newline:
{"code": 200, "data": "get success", "success": true}
{"code": 300, "data": "get failed", "success": false}
you should assign schema as the following:
schema {
fields {
code = int
data = string
success = boolean
}
}
connector will generate data as the following:
| code | data | success |
|---|---|---|
| 200 | get success | true |
If you assign file type to parquet orc, schema option not required, connector can find the schema of upstream data automatically.
If you assign file type to text csv, schema option not supported temporarily, but the subsequent features will support.
Now connector will treat the upstream data as the following:
| lines |
|---|
| The content of every line in file |
fs.defaultFS [string]
Hdfs cluster address.
Example
HdfsFile {
path = "/apps/hive/demo/student"
type = "parquet"
fs.defaultFS = "hdfs://namenode001"
}
HdfsFile {
schema {
fields {
name = string
age = int
}
}
path = "/apps/hive/demo/student"
type = "json"
fs.defaultFS = "hdfs://namenode001"
}