Automatically track Walmart prices and ratings in Google Sheets

flowchart TD trig(["every 4 hours"]):::trigtime s0["search walmart for keyword"]:::svc s1["fetch and render results page"]:::svc s2[["extract product details"]]:::mi s3[("add clean rows to sheet")]:::store trig --> s0 s0 --> s1 s1 -->|"one per one per product listing"| s2 gx{"× price valid"}:::gate s2 --> gx p00["keep row"]:::task gx -->|"valid price found"| p00 p10["drop row"]:::task gx -->|"price missing or invalid"| p10 jn{"○ continue to sheet"}:::gate p00 --> jn p10 --> jn jn --> s3 out[/"updated product listing sheet"/]:::out pay{{"no manual price checking"}}:::pay s3 --> out out --> pay classDef task fill:#e7f6fe,stroke:#34b8f0,color:#2c2a29 classDef svc fill:#f6f8fa,stroke:#7c8795,color:#2c2a29 classDef mi fill:#e7f6fe,stroke:#0079a8,color:#2c2a29,stroke-width:2px classDef human fill:#fff,stroke:#0079a8,color:#0079a8 classDef store fill:#f6f8fa,stroke:#0079a8,color:#2c2a29 classDef trig fill:#00a4eb,stroke:#0079a8,color:#fff,font-weight:bold classDef trigtime fill:#00a4eb,stroke:#0079a8,color:#fff,font-weight:bold classDef trigdata fill:#8ad4f5,stroke:#0079a8,color:#06314c,font-weight:bold classDef gate fill:#fff,stroke:#e8a23d,color:#6b4708,font-weight:bold classDef out fill:#1f9d6b,stroke:#167a53,color:#fff,font-weight:bold classDef pay fill:#06314c,stroke:#021f33,color:#fff