一、技术栈选型
二、系统架构流程图
[Redshift Table] → [S3 Export] → [Lambda Trigger]
↓ |
← [Step Functions Orchestration] →
↓
[Bedrock LLM Processing] → [Result Validation]
↓
[Redshift Update] ← [S3 Processed Data]
三、实现流程(批处理模式)
# Redshift导出数据到S3(使用UNLOAD)
UNLOAD ('SELECT id, raw_text FROM user_content WHERE needs_check = TRUE')
TO 's3://bucket/input/'
IAM_ROLE 'arn:aws:iam::1234567890:role/RedshiftToS3'
FORMAT PARQUET;
import boto3
import json
bedrock = boto3.client(service_name='bedrock-runtime', region_name='us-west-2')
def analyze_text(text):
prompt = f"""请按以下JSON格式分析文本中的语法和语义错误:
{text}
输出要求:
1. has_errors字段为布尔值
2. suggestions字段为字符串,无错误时返回"无"
3. 使用简体中文回复"""
body = json.dumps({
"prompt": prompt,
"max_tokens": 500,
"temperature": 0.2
})
response = bedrock.invoke_model(
body=body,
modelId="meta.llama3-70b-instruct-v1:0",
contentType="application/json"
)
result = json.loads(response['body'].read())
return validate_output(result)
def validate_output(data):
schema = {
"type": "object",
"properties": {
"has_errors": {"type": "boolean"},
"suggestions": {"type": "string"}
},
"required": ["has_errors", "suggestions"]
}
# 使用jsonschema库进行校验
return validate(data, schema)
from psycopg2 import connect
def update_redshift(records):
conn = connect(
host='cluster.region.redshift.amazonaws.com',
user='user',
password='pass',
database='dev',
port=5439
)
with conn.cursor() as cur:
cur.executemany("""
UPDATE content_table
SET has_errors = %s,
suggestions = %s,
last_check = CURRENT_DATE
WHERE id = %s
""", [(r['has_errors'], r['suggestions'], r['id']) for r in records])
conn.commit()
四、关键优化措施
# 使用Pandas进行批处理
def process_batch(batch_df):
results = []
for _, row in batch_df.iterrows():
try:
analysis = analyze_text(row['raw_text'])
results.append({
'id': row['id'],
**analysis
})
except Exception as e:
results.append({
'id': row['id'],
'has_errors': None,
'suggestions': f'ERROR: {str(e)}'
})
return pd.DataFrame(results)
五、Redshift表结构设计
CREATE TABLE content_table (
id BIGINT PRIMARY KEY,
raw_text VARCHAR(2000),
has_errors BOOLEAN,
suggestions VARCHAR(2000),
last_check DATE
)
DISTSTYLE EVEN;
六、部署注意事项
该方案可实现每小时处理约10万条记录(基于LLama3-70B的默认TPS限制),建议通过A/B测试确定最佳批处理大小。最终结果字段包含: