| // +build ignore,OMIT |
| |
| // The server program issues Google search requests. It serves on port 8080. |
| // |
| // The /search endpoint accepts these query params: |
| // q=the Google search query |
| // |
| // For example, http://localhost:8080/search?q=golang serves the first |
| // few Google search results for "golang". |
| package main |
| |
| import ( |
| "encoding/json" |
| "fmt" |
| "html/template" |
| "log" |
| "net/http" |
| "time" |
| |
| "golang.org/x/talks/content/2016/applicative/google" |
| ) |
| |
| func main() { |
| http.HandleFunc("/search", handleSearch) // HL |
| fmt.Println("serving on http://localhost:8080/search") |
| log.Fatal(http.ListenAndServe("localhost:8080", nil)) |
| } |
| |
| // handleSearch handles URLs like "/search?q=golang" by running a |
| // Google search for "golang" and writing the results as HTML to w. |
| // The query parameter "output" selects alternate output formats: |
| // "json" for JSON, "prettyjson" for human-readable JSON. |
| func handleSearch(w http.ResponseWriter, req *http.Request) { // HL |
| log.Println("serving", req.URL) |
| |
| // Check the search query. |
| query := req.FormValue("q") // HL |
| if query == "" { |
| http.Error(w, `missing "q" URL parameter`, http.StatusBadRequest) |
| return |
| } |
| // ENDQUERY OMIT |
| |
| // Run the Google search. |
| start := time.Now() |
| results, err := google.Search(query) // HL |
| elapsed := time.Since(start) |
| if err != nil { |
| http.Error(w, err.Error(), http.StatusInternalServerError) |
| return |
| } |
| // ENDSEARCH OMIT |
| |
| // Create the structured response. |
| type response struct { |
| Results []google.Result |
| Elapsed time.Duration |
| } |
| resp := response{results, elapsed} // HL |
| // ENDRESPONSE OMIT |
| |
| // Render the response. |
| switch req.FormValue("output") { |
| case "json": |
| err = json.NewEncoder(w).Encode(resp) // HL |
| case "prettyjson": |
| var b []byte |
| b, err = json.MarshalIndent(resp, "", " ") // HL |
| if err == nil { |
| _, err = w.Write(b) |
| } |
| default: // HTML |
| err = responseTemplate.Execute(w, resp) // HL |
| } |
| // ENDRENDER OMIT |
| if err != nil { |
| log.Print(err) |
| return |
| } |
| } |
| |
| var responseTemplate = template.Must(template.New("results").Parse(` |
| <html> |
| <head/> |
| <body> |
| <ol> |
| {{range .Results}} |
| <li>{{.Title}} - <a href="{{.URL}}">{{.URL}}</a></li> |
| {{end}} |
| </ol> |
| <p>{{len .Results}} results in {{.Elapsed}}</p> |
| </body> |
| </html> |
| `)) |
